WIP: exec element with initial implementation

Problem is that the main application actually does not create a pty and
instead uses the current one (for better compatability for ssh based
hosting).

The current problem is the fact that the child process should not
take over (and never give back too) the input / output handling of the
current pts. Such that both applications can receive inputs accordingly
(in best case actually controlled by the main application).

.gitea/workflows/release.yaml

@@ -18,12 +18,6 @@ jobs:
         uses: mlugg/setup-zig@v2
         with:
           version: master
-      - name: Lint check
-        run: zig fmt --check .
-      - name: Spell checking
-        uses: crate-ci/typos@v1.39.0
-        with:
-          config: ./.typos-config
       - name: Run tests
         run: zig build --release=fast
       - name: Release build artifacts

.gitea/workflows/test.yaml

@@ -20,7 +20,7 @@ jobs:
       - name: Lint check
         run: zig fmt --check --exclude src/test .
       - name: Spell checking
-        uses: crate-ci/typos@v1.39.0
+        uses: crate-ci/typos@v1.25.0
         with:
           config: ./.typos-config
       - name: Run tests

README.md

@@ -2,7 +2,7 @@
 
 `zterm` is a terminal user interface library (*tui*) to implement terminal (fullscreen or inline) applications.
 
-> [!caution]
+> [!CAUTION]
 > Only builds using the zig master version are tested to work.
 
 ## Demo
@@ -13,7 +13,7 @@ Clone this repository and run `zig build --help` to see the available examples.
 zig build --release=safe -Dexample=demo run
 ```
 
-> [!tip]
+> [!TIP]
 > Every example application can be quit using `ctrl+c`.
 
 See the [wiki](https://gitea.yves-biener.de/yves-biener/zterm/wiki) for a showcase of the examples and the further details.
@@ -33,6 +33,8 @@ const zterm: *Dependency = b.dependency("zterm", .{
     .target = target,
     .optimize = optimize,
 });
+// ...
+exe.root_module.addImport("zterm", zterm.module("zterm"));
 ```
 
 ### Documentation

build.zig

@@ -11,9 +11,7 @@ pub fn build(b: *std.Build) void {
         button,
         input,
         progress,
-        radio_button,
         scrollable,
-        selection,
         // layouts:
         vertical,
         horizontal,
@@ -35,15 +33,20 @@ pub fn build(b: *std.Build) void {
     options.addOption(bool, "debug", debug_rendering);
     const options_module = options.createModule();
 
+    // dependencies
+    const zg = b.dependency("zg", .{
+        .target = target,
+        .optimize = optimize,
+    });
+
     // library
     const lib = b.addModule("zterm", .{
         .root_source_file = b.path("src/root.zig"),
         .target = target,
         .optimize = optimize,
-        .imports = &.{
-            .{ .name = "build_options", .module = options_module },
-        },
     });
+    lib.addImport("code_point", zg.module("code_point"));
+    lib.addImport("build_options", options_module);
 
     //--- Examples ---
     const examples = std.meta.fields(Examples);
@@ -51,7 +54,6 @@ pub fn build(b: *std.Build) void {
         if (@as(Examples, @enumFromInt(e.value)) == .all) continue; // skip `.all` entry
         const demo = b.addExecutable(.{
             .name = e.name,
-            .root_module = b.createModule(.{
             .root_source_file = b.path(switch (@as(Examples, @enumFromInt(e.value))) {
                 .demo => "examples/demo.zig",
                 .continuous => "examples/continuous.zig",
@@ -60,9 +62,7 @@ pub fn build(b: *std.Build) void {
                 .button => "examples/elements/button.zig",
                 .input => "examples/elements/input.zig",
                 .progress => "examples/elements/progress.zig",
-                    .radio_button => "examples/elements/radio-button.zig",
                 .scrollable => "examples/elements/scrollable.zig",
-                    .selection => "examples/elements/selection.zig",
                 // layouts:
                 .vertical => "examples/layouts/vertical.zig",
                 .horizontal => "examples/layouts/horizontal.zig",
@@ -77,26 +77,22 @@ pub fn build(b: *std.Build) void {
             }),
             .target = target,
             .optimize = optimize,
-                .imports = &.{
-                    .{ .name = "zterm", .module = lib },
-                },
-            }),
         });
+        // import dependencies
+        demo.root_module.addImport("zterm", lib);
         // mapping of user selected example to compile step
         if (@intFromEnum(example) == e.value or example == .all) b.installArtifact(demo);
     }
 
     // zig build test
     const lib_unit_tests = b.addTest(.{
-        .root_module = b.createModule(.{
         .root_source_file = b.path("src/root.zig"),
         .target = target,
         .optimize = optimize,
-            .imports = &.{
-                .{ .name = "build_options", .module = options_module },
-            },
-        }),
     });
+    lib_unit_tests.root_module.addImport("code_point", zg.module("code_point"));
+    lib_unit_tests.root_module.addImport("DisplayWidth", zg.module("DisplayWidth"));
+    lib_unit_tests.root_module.addImport("build_options", options_module);
 
     const run_lib_unit_tests = b.addRunArtifact(lib_unit_tests);
 

build.zig.zon

@@ -35,7 +35,12 @@
     // `zig build --fetch` can be used to fetch all dependencies of a package, recursively.
     // Once all dependencies are fetched, `zig build` no longer requires
     // internet connectivity.
-    .dependencies = .{},
+    .dependencies = .{
+        .zg = .{
+            .url = "git+https://codeberg.org/atman/zg#9427a9e53aaa29ee071f4dcb35b809a699d75aa9",
+            .hash = "zg-0.14.1-oGqU3IQ_tALZIiBN026_NTaPJqU-Upm8P_C7QED2Rzm8",
+        },
+    },
     .paths = .{
         "LICENSE",
         "build.zig",

examples/continuous.zig

@@ -5,7 +5,7 @@ const QuitText = struct {
         return .{ .ptr = this, .vtable = &.{ .content = content } };
     }
 
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
@@ -41,7 +41,7 @@ const Spinner = struct {
         };
     }
 
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         const this: *@This() = @ptrCast(@alignCast(ctx));
         assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
@@ -57,20 +57,18 @@ const Spinner = struct {
 };
 
 const InputField = struct {
-    allocator: std.mem.Allocator,
     input: std.ArrayList(u21),
     queue: *App.Queue,
 
     pub fn init(allocator: std.mem.Allocator, queue: *App.Queue) @This() {
         return .{
-            .allocator = allocator,
+            .input = .init(allocator),
-            .input = std.ArrayList(u21).initCapacity(allocator, 8) catch unreachable,
             .queue = queue,
         };
     }
 
-    pub fn deinit(this: *@This()) void {
+    pub fn deinit(this: @This()) void {
-        this.input.deinit(this.allocator);
+        this.input.deinit();
     }
 
     pub fn element(this: *@This()) App.Element {
@@ -83,14 +81,14 @@ const InputField = struct {
         };
     }
 
-    fn handle(ctx: *anyopaque, _: *App.Model, event: App.Event) !void {
+    fn handle(ctx: *anyopaque, event: App.Event) !void {
         const this: *@This() = @ptrCast(@alignCast(ctx));
         switch (event) {
             .key => |key| {
-                if (key.isUnicode()) try this.input.append(this.allocator, key.cp);
+                if (key.isAscii()) try this.input.append(key.cp);
 
                 if (key.eql(.{ .cp = zterm.input.Enter }) or key.eql(.{ .cp = zterm.input.KpEnter }))
-                    this.queue.push(.{ .accept = try this.input.toOwnedSlice(this.allocator) });
+                    this.queue.push(.{ .accept = try this.input.toOwnedSlice() });
 
                 if (key.eql(.{ .cp = zterm.input.Backspace }))
                     _ = this.input.pop();
@@ -102,7 +100,7 @@ const InputField = struct {
         }
     }
 
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         const this: *@This() = @ptrCast(@alignCast(ctx));
         assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
@@ -133,10 +131,7 @@ pub fn main() !void {
 
     const allocator = gpa.allocator();
 
-    var threaded_io: std.Io.Threaded = .init(allocator, .{});
+    var app: App = .init;
-    defer threaded_io.deinit();
-
-    var app: App = .init(threaded_io.ioBasic(), .{});
     var renderer = zterm.Renderer.Buffered.init(allocator);
     defer renderer.deinit();
 
@@ -156,7 +151,7 @@ pub fn main() !void {
     defer container.deinit();
 
     try container.append(try App.Container.init(allocator, .{
-        .rectangle = .{ .fill = .lightgrey },
+        .rectangle = .{ .fill = .light_grey },
         .size = .{
             .grow = .horizontal,
             .dim = .{ .y = 10 },
@@ -164,7 +159,7 @@ pub fn main() !void {
     }, input_field.element()));
 
     const nested_container: App.Container = try .init(allocator, .{
-        .rectangle = .{ .fill = .lightgrey },
+        .rectangle = .{ .fill = .light_grey },
     }, spinner.element());
     try container.append(nested_container);
 
@@ -181,7 +176,7 @@ pub fn main() !void {
         if (now_ms >= next_frame_ms) {
             next_frame_ms = now_ms + tick_ms;
         } else {
-            std.Thread.sleep((next_frame_ms - now_ms) * time.ns_per_ms);
+            time.sleep((next_frame_ms - now_ms) * time.ns_per_ms);
             next_frame_ms += tick_ms;
         }
 
@@ -217,7 +212,7 @@ pub fn main() !void {
                 else => {},
             }
 
-            container.handle(&app.model, event) catch |err| app.postEvent(.{
+            container.handle(event) catch |err| app.postEvent(.{
                 .err = .{
                     .err = err,
                     .msg = "Container Event handling failed",
@@ -231,9 +226,9 @@ pub fn main() !void {
             }
         }
 
-        container.resize(&app.model, try renderer.resize());
+        container.resize(try renderer.resize());
-        container.reposition(&app.model, .{});
+        container.reposition(.{});
-        try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
+        try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }
 }
@@ -245,6 +240,6 @@ const std = @import("std");
 const time = std.time;
 const assert = std.debug.assert;
 const zterm = @import("zterm");
-const App = zterm.App(struct {}, union(enum) {
+const App = zterm.App(union(enum) {
     accept: []u21,
 });

examples/demo.zig

@@ -5,7 +5,7 @@ const QuitText = struct {
         return .{ .ptr = this, .vtable = &.{ .content = content } };
     }
 
-    pub fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+    pub fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
@@ -27,14 +27,13 @@ const QuitText = struct {
 pub fn main() !void {
     errdefer |err| log.err("Application Error: {any}", .{err});
 
+    // TODO maybe create own allocator as some sort of arena allocator to have consistent memory usage
     var gpa: std.heap.DebugAllocator(.{}) = .init;
     defer if (gpa.deinit() == .leak) log.err("memory leak", .{});
 
     const allocator = gpa.allocator();
-    var threaded_io: std.Io.Threaded = .init(allocator, .{});
-    defer threaded_io.deinit();
 
-    var app: App = .init(threaded_io.ioBasic(), .{});
+    var app: App = .init;
     var renderer = zterm.Renderer.Buffered.init(allocator);
     defer renderer.deinit();
 
@@ -58,14 +57,15 @@ pub fn main() !void {
         },
     }, .{});
     try box.append(try App.Container.init(allocator, .{
-        .rectangle = .{ .fill = .lightgreen },
+        .rectangle = .{ .fill = .light_green },
     }, .{}));
     try box.append(try App.Container.init(allocator, .{
-        .rectangle = .{ .fill = .lightgreen },
+        .rectangle = .{ .fill = .light_green },
     }, .{}));
     try box.append(try App.Container.init(allocator, .{
-        .rectangle = .{ .fill = .lightgreen },
+        .rectangle = .{ .fill = .light_green },
     }, .{}));
+    defer box.deinit();
 
     var scrollable: App.Scrollable = .init(box, .disabled);
 
@@ -79,54 +79,29 @@ pub fn main() !void {
     }, quit_text.element());
     try container.append(try App.Container.init(allocator, .{}, scrollable.element()));
 
-    var nested_container: App.Container = try .init(allocator, .{
+    var environment = try std.process.getEnvMap(allocator);
-        .layout = .{
+    defer environment.deinit();
-            .direction = .vertical,
+
-            .separator = .{
+    var editor: App.Exec = .init(
-                .enabled = true,
+        allocator,
-            },
+        &.{
-        },
+            "tty",
-    }, .{});
-    var inner_container: App.Container = try .init(allocator, .{
-        .layout = .{
-            .direction = .vertical,
         },
+        &environment,
+        &app.queue,
+    );
+    defer editor.deinit();
+
+    try container.append(try App.Container.init(allocator, .{
         .border = .{
-            .color = .lightblue,
+            .color = .light_blue,
             .sides = .all,
         },
-    }, .{});
-    try inner_container.append(try .init(allocator, .{
-        .rectangle = .{
-            .fill = .blue,
-        },
         .size = .{
-            .grow = .horizontal,
+            .dim = .{ .x = 100 },
-            .dim = .{ .y = 5 },
         },
-    }, .{}));
+    }, editor.element()));
-    try inner_container.append(try .init(allocator, .{
+
-        .rectangle = .{
-            .fill = .red,
-        },
-        .size = .{
-            .grow = .horizontal,
-            .dim = .{ .y = 5 },
-        },
-    }, .{}));
-    try inner_container.append(try .init(allocator, .{
-        .rectangle = .{
-            .fill = .green,
-        },
-    }, .{}));
-    try nested_container.append(inner_container);
-    try nested_container.append(try .init(allocator, .{
-        .size = .{
-            .grow = .horizontal,
-            .dim = .{ .y = 1 },
-        },
-    }, .{}));
-    try container.append(nested_container);
     try container.append(try App.Container.init(allocator, .{
         .rectangle = .{ .fill = .blue },
         .size = .{
@@ -138,6 +113,11 @@ pub fn main() !void {
     try app.start();
     defer app.stop() catch |err| log.err("Failed to stop application: {any}", .{err});
 
+    var process_in: std.ArrayListUnmanaged(u8) = .empty;
+    defer process_in.deinit(allocator);
+    var process_out: std.ArrayListUnmanaged(u8) = .empty;
+    defer process_out.deinit(allocator);
+
     // event loop
     while (true) {
         const event = app.nextEvent();
@@ -145,30 +125,14 @@ pub fn main() !void {
 
         // pre event handling
         switch (event) {
-            .key => |key| {
+            .key => |key| if (key.eql(.{ .cp = 'c', .mod = .{ .ctrl = true } })) app.quit(),
-                if (key.eql(.{ .cp = 'c', .mod = .{ .ctrl = true } })) app.quit();
-
-                if (key.eql(.{ .cp = 'n', .mod = .{ .ctrl = true } })) {
-                    try app.interrupt();
-                    renderer.size = .{}; // reset size, such that next resize will cause a full re-draw!
-                    defer app.start() catch @panic("could not start app event loop");
-                    var child = std.process.Child.init(&.{"hx"}, allocator);
-                    _ = child.spawnAndWait(threaded_io.io()) catch |err| app.postEvent(.{
-                        .err = .{
-                            .err = err,
-                            .msg = "Spawning $EDITOR failed",
-                        },
-                    });
-                    continue;
-                }
-            },
             // NOTE errors could be displayed in another container in case one was received, etc. to provide the user with feedback
             .err => |err| log.err("Received {s} with message: {s}", .{ @errorName(err.err), err.msg }),
             else => {},
         }
 
         // NOTE returned errors should be propagated back to the application
-        container.handle(&app.model, event) catch |err| app.postEvent(.{
+        container.handle(event) catch |err| app.postEvent(.{
             .err = .{
                 .err = err,
                 .msg = "Container Event handling failed",
@@ -181,9 +145,9 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(&app.model, try renderer.resize());
+        container.resize(try renderer.resize());
-        container.reposition(&app.model, .{});
+        container.reposition(.{});
-        try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
+        try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }
 }
@@ -195,4 +159,4 @@ const std = @import("std");
 const assert = std.debug.assert;
 const zterm = @import("zterm");
 const input = zterm.input;
-const App = zterm.App(struct {}, union(enum) {});
+const App = zterm.App(union(enum) {});

examples/elements/alignment.zig

@@ -5,7 +5,7 @@ const QuitText = struct {
         return .{ .ptr = this, .vtable = &.{ .content = content } };
     }
 
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
@@ -32,10 +32,7 @@ pub fn main() !void {
 
     const allocator = gpa.allocator();
 
-    var threaded_io: std.Io.Threaded = .init(allocator, .{});
+    var app: App = .init;
-    defer threaded_io.deinit();
-
-    var app: App = .init(threaded_io.ioBasic(), .{});
     var renderer = zterm.Renderer.Buffered.init(allocator);
     defer renderer.deinit();
 
@@ -73,7 +70,7 @@ pub fn main() !void {
             else => {},
         }
 
-        container.handle(&app.model, event) catch |err| app.postEvent(.{
+        container.handle(event) catch |err| app.postEvent(.{
             .err = .{
                 .err = err,
                 .msg = "Container Event handling failed",
@@ -86,9 +83,9 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(&app.model, try renderer.resize());
+        container.resize(try renderer.resize());
-        container.reposition(&app.model, .{});
+        container.reposition(.{});
-        try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
+        try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }
 }
@@ -99,4 +96,4 @@ const log = std.log.scoped(.default);
 const std = @import("std");
 const assert = std.debug.assert;
 const zterm = @import("zterm");
-const App = zterm.App(struct {}, union(enum) {});
+const App = zterm.App(union(enum) {});

examples/elements/button.zig

@@ -5,7 +5,7 @@ const QuitText = struct {
         return .{ .ptr = this, .vtable = &.{ .content = content } };
     }
 
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
@@ -40,7 +40,7 @@ const Clickable = struct {
         };
     }
 
-    fn handle(ctx: *anyopaque, _: *App.Model, event: App.Event) !void {
+    fn handle(ctx: *anyopaque, event: App.Event) !void {
         const this: *@This() = @ptrCast(@alignCast(ctx));
         switch (event) {
             .mouse => |mouse| if (mouse.button == .left and mouse.kind == .release) {
@@ -55,7 +55,7 @@ const Clickable = struct {
         }
     }
 
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         const this: *@This() = @ptrCast(@alignCast(ctx));
         assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
@@ -82,10 +82,7 @@ pub fn main() !void {
 
     const allocator = gpa.allocator();
 
-    var threaded_io: std.Io.Threaded = .init(allocator, .{});
+    var app: App = .init;
-    defer threaded_io.deinit();
-
-    var app: App = .init(threaded_io.ioBasic(), .{});
     var renderer = zterm.Renderer.Buffered.init(allocator);
     defer renderer.deinit();
 
@@ -102,7 +99,7 @@ pub fn main() !void {
     }, quit_text.element());
     defer container.deinit();
 
-    try container.append(try App.Container.init(allocator, .{ .rectangle = .{ .fill = .lightgrey } }, element));
+    try container.append(try App.Container.init(allocator, .{ .rectangle = .{ .fill = .light_grey } }, element));
     try container.append(try App.Container.init(allocator, .{ .rectangle = .{ .fill = .black } }, button.element()));
 
     try app.start();
@@ -122,7 +119,7 @@ pub fn main() !void {
             else => {},
         }
 
-        container.handle(&app.model, event) catch |err| app.postEvent(.{
+        container.handle(event) catch |err| app.postEvent(.{
             .err = .{
                 .err = err,
                 .msg = "Container Event handling failed",
@@ -135,9 +132,9 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(&app.model, try renderer.resize());
+        container.resize(try renderer.resize());
-        container.reposition(&app.model, .{});
+        container.reposition(.{});
-        try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
+        try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }
 }
@@ -148,10 +145,7 @@ const log = std.log.scoped(.default);
 const std = @import("std");
 const assert = std.debug.assert;
 const zterm = @import("zterm");
-const App = zterm.App(
+const App = zterm.App(union(enum) {
-    struct {},
-    union(enum) {
     click: [:0]const u8,
     accept,
-    },
+});
-);

examples/elements/input.zig

@@ -5,7 +5,7 @@ const QuitText = struct {
         return .{ .ptr = this, .vtable = &.{ .content = content } };
     }
 
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
@@ -37,7 +37,7 @@ const MouseDraw = struct {
         };
     }
 
-    fn handle(ctx: *anyopaque, _: *App.Model, event: App.Event) !void {
+    fn handle(ctx: *anyopaque, event: App.Event) !void {
         const this: *@This() = @ptrCast(@alignCast(ctx));
         switch (event) {
             .mouse => |mouse| this.position = .{ .x = mouse.x, .y = mouse.y },
@@ -45,7 +45,7 @@ const MouseDraw = struct {
         }
     }
 
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
         const this: *@This() = @ptrCast(@alignCast(ctx));
 
@@ -65,14 +65,13 @@ pub fn main() !void {
 
     const allocator = gpa.allocator();
 
-    var threaded_io: std.Io.Threaded = .init(allocator, .{});
+    var app: App = .init;
-    defer threaded_io.deinit();
-
-    var app: App = .init(threaded_io.ioBasic(), .{});
     var renderer = zterm.Renderer.Buffered.init(allocator);
     defer renderer.deinit();
 
-    var input_field: App.Input(.accept) = .init(allocator, &app.queue, .init(.black, .blue));
+    var input_field: App.Input(.accept) = .init(allocator, &app.queue, .init(.black));
+    defer input_field.deinit();
+
     var mouse_draw: MouseDraw = .{};
     var second_mouse_draw: MouseDraw = .{};
     var quit_text: QuitText = .{};
@@ -87,7 +86,7 @@ pub fn main() !void {
     defer container.deinit();
 
     try container.append(try App.Container.init(allocator, .{
-        .rectangle = .{ .fill = .lightgrey },
+        .rectangle = .{ .fill = .light_grey },
         .size = .{
             .grow = .horizontal,
             .dim = .{ .y = 1 },
@@ -99,7 +98,7 @@ pub fn main() !void {
             .sides = .all,
             .color = .black,
         },
-        .rectangle = .{ .fill = .lightgrey },
+        .rectangle = .{ .fill = .light_grey },
         .layout = .{
             .separator = .{
                 .enabled = true,
@@ -108,10 +107,10 @@ pub fn main() !void {
         },
     }, .{});
     try nested_container.append(try .init(allocator, .{
-        .rectangle = .{ .fill = .lightgrey },
+        .rectangle = .{ .fill = .light_grey },
     }, mouse_draw.element()));
     try nested_container.append(try .init(allocator, .{
-        .rectangle = .{ .fill = .lightgrey },
+        .rectangle = .{ .fill = .light_grey },
     }, second_mouse_draw.element()));
     try container.append(nested_container);
 
@@ -134,7 +133,7 @@ pub fn main() !void {
             else => {},
         }
 
-        container.handle(&app.model, event) catch |err| app.postEvent(.{
+        container.handle(event) catch |err| app.postEvent(.{
             .err = .{
                 .err = err,
                 .msg = "Container Event handling failed",
@@ -147,9 +146,9 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(&app.model, try renderer.resize());
+        container.resize(try renderer.resize());
-        container.reposition(&app.model, .{});
+        container.reposition(.{});
-        try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
+        try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }
 }
@@ -162,9 +161,6 @@ const assert = std.debug.assert;
 const zterm = @import("zterm");
 const Color = zterm.Color;
 
-const App = zterm.App(
+const App = zterm.App(union(enum) {
-    struct {},
-    union(enum) {
     accept: []u8,
-    },
+});
-);

examples/elements/progress.zig

@@ -5,7 +5,7 @@ const QuitText = struct {
         return .{ .ptr = this, .vtable = &.{ .content = content } };
     }
 
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
@@ -32,62 +32,25 @@ pub fn main() !void {
 
     const allocator = gpa.allocator();
 
-    var threaded_io: std.Io.Threaded = .init(allocator, .{});
+    var app: App = .init;
-    defer threaded_io.deinit();
-
-    var app: App = .init(threaded_io.ioBasic(), .{});
     var renderer = zterm.Renderer.Buffered.init(allocator);
     defer renderer.deinit();
 
     var progress_percent: u8 = 0;
-    var quit_text: QuitText = .{};
-
-    var container = try App.Container.init(allocator, .{
-        .layout = .{ .padding = .all(5), .direction = .vertical },
-    }, quit_text.element());
-    defer container.deinit();
-
-    {
     var progress: App.Progress(.progress) = .init(&app.queue, .{
-            .percent = .{
+        .percent = .{ .enabled = true },
-                .enabled = true,
-                .alignment = .left,
-            },
-            .fg = .blue,
-            .bg = .grey,
-        });
-        try container.append(try App.Container.init(allocator, .{}, progress.element()));
-    }
-    {
-        var progress: App.Progress(.progress) = .init(&app.queue, .{
-            .percent = .{
-                .enabled = true,
-                .alignment = .middle, // default
-            },
-            .fg = .red,
-            .bg = .grey,
-        });
-        try container.append(try App.Container.init(allocator, .{}, progress.element()));
-    }
-    {
-        var progress: App.Progress(.progress) = .init(&app.queue, .{
-            .percent = .{
-                .enabled = true,
-                .alignment = .right,
-            },
         .fg = .green,
         .bg = .grey,
     });
+    var quit_text: QuitText = .{};
+
+    var container = try App.Container.init(allocator, .{
+        .layout = .{ .padding = .all(5) },
+    }, quit_text.element());
+    defer container.deinit();
+
     try container.append(try App.Container.init(allocator, .{}, progress.element()));
-    }
+
-    {
-        var progress: App.Progress(.progress) = .init(&app.queue, .{
-            .percent = .{ .enabled = false },
-            .fg = .default,
-            .bg = .grey,
-        });
-        try container.append(try App.Container.init(allocator, .{}, progress.element()));
-    }
     try app.start();
     defer app.stop() catch |err| log.err("Failed to stop application: {any}", .{err});
 
@@ -104,7 +67,7 @@ pub fn main() !void {
         if (now_ms >= next_frame_ms) {
             next_frame_ms = now_ms + tick_ms;
         } else {
-            std.Thread.sleep((next_frame_ms - now_ms) * time.ns_per_ms);
+            time.sleep((next_frame_ms - now_ms) * time.ns_per_ms);
             next_frame_ms += tick_ms;
         }
 
@@ -141,7 +104,7 @@ pub fn main() !void {
                 else => {},
             }
 
-            container.handle(&app.model, event) catch |err| app.postEvent(.{
+            container.handle(event) catch |err| app.postEvent(.{
                 .err = .{
                     .err = err,
                     .msg = "Container Event handling failed",
@@ -155,9 +118,9 @@ pub fn main() !void {
             }
         }
 
-        container.resize(&app.model, try renderer.resize());
+        container.resize(try renderer.resize());
-        container.reposition(&app.model, .{});
+        container.reposition(.{});
-        try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
+        try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }
 }
@@ -169,9 +132,6 @@ const std = @import("std");
 const time = std.time;
 const assert = std.debug.assert;
 const zterm = @import("zterm");
-const App = zterm.App(
+const App = zterm.App(union(enum) {
-    struct {},
-    union(enum) {
     progress: u8,
-    },
+});
-);

examples/elements/radio-button.zig

@@ -1,101 +0,0 @@
-const QuitText = struct {
-    const text = "Press ctrl+c to quit.";
-
-    pub fn element(this: *@This()) App.Element {
-        return .{ .ptr = this, .vtable = &.{ .content = content } };
-    }
-
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
-        _ = ctx;
-        assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
-
-        const row = 2;
-        const col = size.x / 2 -| (text.len / 2);
-        const anchor = (row * size.x) + col;
-
-        for (text, 0..) |cp, idx| {
-            cells[anchor + idx].style.fg = .white;
-            cells[anchor + idx].style.bg = .black;
-            cells[anchor + idx].cp = cp;
-
-            // NOTE do not write over the contents of this `Container`'s `Size`
-            if (anchor + idx == cells.len - 1) break;
-        }
-    }
-};
-
-pub fn main() !void {
-    errdefer |err| log.err("Application Error: {any}", .{err});
-
-    var gpa: std.heap.DebugAllocator(.{}) = .init;
-    defer if (gpa.deinit() == .leak) log.err("memory leak", .{});
-
-    const allocator = gpa.allocator();
-
-    var threaded_io: std.Io.Threaded = .init(allocator, .{});
-    defer threaded_io.deinit();
-
-    var app: App = .init(threaded_io.ioBasic(), .{});
-    var renderer = zterm.Renderer.Buffered.init(allocator);
-    defer renderer.deinit();
-
-    var radiobutton: App.RadioButton = .init(false, .{
-        .label = "Test Radio Button",
-        .style = .squared,
-    });
-    var button: App.Button(.accept) = .init(&app.queue, .init(.default, "Button"));
-    var quit_text: QuitText = .{};
-
-    var container = try App.Container.init(allocator, .{
-        .rectangle = .{ .fill = .grey },
-        .layout = .{ .padding = .all(5) },
-    }, quit_text.element());
-    defer container.deinit();
-    try container.append(try .init(allocator, .{}, radiobutton.element()));
-    try container.append(try App.Container.init(allocator, .{ .rectangle = .{ .fill = .black } }, button.element()));
-
-    try app.start();
-    defer app.stop() catch |err| log.err("Failed to stop application: {any}", .{err});
-
-    // event loop
-    while (true) {
-        const event = app.nextEvent();
-        log.debug("received event: {s}", .{@tagName(event)});
-
-        // pre event handling
-        switch (event) {
-            .key => |key| if (key.eql(.{ .cp = 'c', .mod = .{ .ctrl = true } })) app.quit(),
-            .accept => log.info("Clicked built-in button using the mouse", .{}),
-            .err => |err| log.err("Received {s} with message: {s}", .{ @errorName(err.err), err.msg }),
-            else => {},
-        }
-
-        container.handle(&app.model, event) catch |err| app.postEvent(.{
-            .err = .{
-                .err = err,
-                .msg = "Container Event handling failed",
-            },
-        });
-
-        // post event handling
-        switch (event) {
-            .quit => break,
-            else => {},
-        }
-
-        container.resize(&app.model, try renderer.resize());
-        container.reposition(&app.model, .{});
-        try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
-        try renderer.flush();
-    }
-}
-
-pub const panic = App.panic_handler;
-const log = std.log.scoped(.default);
-
-const std = @import("std");
-const assert = std.debug.assert;
-const zterm = @import("zterm");
-const App = zterm.App(struct {}, union(enum) {
-    accept,
-});

examples/elements/scrollable.zig

@@ -5,7 +5,7 @@ const QuitText = struct {
         return .{ .ptr = this, .vtable = &.{ .content = content } };
     }
 
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
@@ -34,7 +34,7 @@ const HelloWorldText = packed struct {
         };
     }
 
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
@@ -56,6 +56,7 @@ const HelloWorldText = packed struct {
 pub fn main() !void {
     errdefer |err| log.err("Application Error: {any}", .{err});
 
+    // TODO maybe create own allocator as some sort of arena allocator to have consistent memory usage
     var gpa: std.heap.DebugAllocator(.{}) = .init;
     defer {
         const deinit_status = gpa.deinit();
@@ -65,10 +66,7 @@ pub fn main() !void {
     }
     const allocator = gpa.allocator();
 
-    var threaded_io: std.Io.Threaded = .init(allocator, .{});
+    var app: App = .init;
-    defer threaded_io.deinit();
-
-    var app: App = .init(threaded_io.ioBasic(), .{});
     var renderer = zterm.Renderer.Buffered.init(allocator);
     defer renderer.deinit();
 
@@ -89,23 +87,24 @@ pub fn main() !void {
         },
     }, .{});
     try top_box.append(try App.Container.init(allocator, .{
-        .rectangle = .{ .fill = .lightgreen },
+        .rectangle = .{ .fill = .light_green },
         .size = .{
             .dim = .{ .y = 30 },
         },
     }, .{}));
     try top_box.append(try App.Container.init(allocator, .{
-        .rectangle = .{ .fill = .lightgreen },
+        .rectangle = .{ .fill = .light_green },
         .size = .{
             .dim = .{ .y = 5 },
         },
     }, element));
     try top_box.append(try App.Container.init(allocator, .{
-        .rectangle = .{ .fill = .lightgreen },
+        .rectangle = .{ .fill = .light_green },
         .size = .{
             .dim = .{ .y = 2 },
         },
     }, .{}));
+    defer top_box.deinit();
 
     var bottom_box = try App.Container.init(allocator, .{
         .border = .{
@@ -133,6 +132,7 @@ pub fn main() !void {
     try bottom_box.append(try App.Container.init(allocator, .{
         .rectangle = .{ .fill = .grey },
     }, .{}));
+    defer bottom_box.deinit();
 
     var container = try App.Container.init(allocator, .{
         .layout = .{
@@ -148,10 +148,10 @@ pub fn main() !void {
     defer container.deinit();
 
     // place empty container containing the element of the scrollable Container.
-    var scrollable_top: App.Scrollable = .init(top_box, .enabled(.default, false));
+    var scrollable_top: App.Scrollable = .init(top_box, .enabled(.grey));
     try container.append(try App.Container.init(allocator, .{}, scrollable_top.element()));
 
-    var scrollable_bottom: App.Scrollable = .init(bottom_box, .enabled(.white, true));
+    var scrollable_bottom: App.Scrollable = .init(bottom_box, .enabled(.white));
     try container.append(try App.Container.init(allocator, .{}, scrollable_bottom.element()));
 
     try app.start();
@@ -169,7 +169,7 @@ pub fn main() !void {
             else => {},
         }
 
-        container.handle(&app.model, event) catch |err| app.postEvent(.{
+        container.handle(event) catch |err| app.postEvent(.{
             .err = .{
                 .err = err,
                 .msg = "Container Event handling failed",
@@ -182,9 +182,9 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(&app.model, try renderer.resize());
+        container.resize(try renderer.resize());
-        container.reposition(&app.model, .{});
+        container.reposition(.{});
-        try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
+        try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }
 }
@@ -196,4 +196,4 @@ const std = @import("std");
 const assert = std.debug.assert;
 const zterm = @import("zterm");
 const input = zterm.input;
-const App = zterm.App(struct {}, union(enum) {});
+const App = zterm.App(union(enum) {});

examples/elements/selection.zig

@@ -1,100 +0,0 @@
-const QuitText = struct {
-    const text = "Press ctrl+c to quit.";
-
-    pub fn element(this: *@This()) App.Element {
-        return .{ .ptr = this, .vtable = &.{ .content = content } };
-    }
-
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
-        _ = ctx;
-        assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
-
-        const row = 2;
-        const col = size.x / 2 -| (text.len / 2);
-        const anchor = (row * size.x) + col;
-
-        for (text, 0..) |cp, idx| {
-            cells[anchor + idx].style.fg = .white;
-            cells[anchor + idx].style.bg = .black;
-            cells[anchor + idx].cp = cp;
-
-            // NOTE do not write over the contents of this `Container`'s `Size`
-            if (anchor + idx == cells.len - 1) break;
-        }
-    }
-};
-
-pub fn main() !void {
-    errdefer |err| log.err("Application Error: {any}", .{err});
-
-    var gpa: std.heap.DebugAllocator(.{}) = .init;
-    defer if (gpa.deinit() == .leak) log.err("memory leak", .{});
-
-    const allocator = gpa.allocator();
-
-    var threaded_io: std.Io.Threaded = .init(allocator, .{});
-    defer threaded_io.deinit();
-
-    var app: App = .init(threaded_io.ioBasic(), .{});
-    var renderer = zterm.Renderer.Buffered.init(allocator);
-    defer renderer.deinit();
-
-    var selection: App.Selection(enum {
-        one,
-        two,
-        three,
-    }) = .init(.{
-        .label = "Selection",
-    });
-    var quit_text: QuitText = .{};
-
-    var container = try App.Container.init(allocator, .{
-        .rectangle = .{ .fill = .grey },
-        .layout = .{ .padding = .all(5) },
-    }, quit_text.element());
-    defer container.deinit();
-    try container.append(try .init(allocator, .{}, selection.element()));
-
-    try app.start();
-    defer app.stop() catch |err| log.err("Failed to stop application: {any}", .{err});
-
-    // event loop
-    while (true) {
-        const event = app.nextEvent();
-        log.debug("received event: {s}", .{@tagName(event)});
-
-        // pre event handling
-        switch (event) {
-            .key => |key| if (key.eql(.{ .cp = 'c', .mod = .{ .ctrl = true } })) app.quit(),
-            .err => |err| log.err("Received {s} with message: {s}", .{ @errorName(err.err), err.msg }),
-            else => {},
-        }
-
-        container.handle(&app.model, event) catch |err| app.postEvent(.{
-            .err = .{
-                .err = err,
-                .msg = "Container Event handling failed",
-            },
-        });
-
-        // post event handling
-        switch (event) {
-            .quit => break,
-            else => {},
-        }
-
-        container.resize(&app.model, try renderer.resize());
-        container.reposition(&app.model, .{});
-        try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
-        try renderer.flush();
-    }
-}
-
-pub const panic = App.panic_handler;
-const log = std.log.scoped(.default);
-
-const std = @import("std");
-const assert = std.debug.assert;
-const zterm = @import("zterm");
-const Error = zterm.Error;
-const App = zterm.App(struct {}, union(enum) {});

examples/errors.zig

@@ -5,7 +5,7 @@ const QuitText = struct {
         return .{ .ptr = this, .vtable = &.{ .content = content } };
     }
 
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
@@ -31,7 +31,7 @@ const InfoText = struct {
         return .{ .ptr = this, .vtable = &.{ .content = content } };
     }
 
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
@@ -57,7 +57,7 @@ const ErrorNotification = struct {
         return .{ .ptr = this, .vtable = &.{ .handle = handle, .content = content } };
     }
 
-    fn handle(ctx: *anyopaque, _: *App.Model, event: App.Event) !void {
+    fn handle(ctx: *anyopaque, event: App.Event) !void {
         const this: *@This() = @ptrCast(@alignCast(ctx));
         switch (event) {
             .key => |key| if (!key.isAscii()) return zterm.Error.TooSmall,
@@ -66,7 +66,7 @@ const ErrorNotification = struct {
         }
     }
 
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         const this: *@This() = @ptrCast(@alignCast(ctx));
         assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
@@ -97,10 +97,7 @@ pub fn main() !void {
 
     const allocator = gpa.allocator();
 
-    var threaded_io: std.Io.Threaded = .init(allocator, .{});
+    var app: App = .init;
-    defer threaded_io.deinit();
-
-    var app: App = .init(threaded_io.ioBasic(), .{});
     var renderer = zterm.Renderer.Buffered.init(allocator);
     defer renderer.deinit();
 
@@ -133,7 +130,7 @@ pub fn main() !void {
             else => {},
         }
 
-        container.handle(&app.model, event) catch |err| app.postEvent(.{
+        container.handle(event) catch |err| app.postEvent(.{
             .err = .{
                 .err = err,
                 .msg = "Container Event handling failed",
@@ -146,9 +143,9 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(&app.model, try renderer.resize());
+        container.resize(try renderer.resize());
-        container.reposition(&app.model, .{});
+        container.reposition(.{});
-        try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
+        try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }
 }
@@ -159,4 +156,4 @@ const log = std.log.scoped(.default);
 const std = @import("std");
 const assert = std.debug.assert;
 const zterm = @import("zterm");
-const App = zterm.App(struct {}, union(enum) {});
+const App = zterm.App(union(enum) {});

examples/layouts/grid.zig

@@ -8,7 +8,7 @@ const QuitText = struct {
         };
     }
 
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
@@ -35,10 +35,7 @@ pub fn main() !void {
 
     const allocator = gpa.allocator();
 
-    var threaded_io: std.Io.Threaded = .init(allocator, .{});
+    var app: App = .init;
-    defer threaded_io.deinit();
-
-    var app: App = .init(threaded_io.ioBasic(), .{});
     var renderer = zterm.Renderer.Buffered.init(allocator);
     defer renderer.deinit();
 
@@ -89,7 +86,7 @@ pub fn main() !void {
         }
 
         // NOTE returned errors should be propagated back to the application
-        container.handle(&app.model, event) catch |err| app.postEvent(.{
+        container.handle(event) catch |err| app.postEvent(.{
             .err = .{
                 .err = err,
                 .msg = "Container Event handling failed",
@@ -102,9 +99,9 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(&app.model, try renderer.resize());
+        container.resize(try renderer.resize());
-        container.reposition(&app.model, .{});
+        container.reposition(.{});
-        try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
+        try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }
 }
@@ -115,4 +112,4 @@ const log = std.log.scoped(.default);
 const std = @import("std");
 const assert = std.debug.assert;
 const zterm = @import("zterm");
-const App = zterm.App(struct {}, union(enum) {});
+const App = zterm.App(union(enum) {});

examples/layouts/horizontal.zig

@@ -8,7 +8,7 @@ const QuitText = struct {
         };
     }
 
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
@@ -35,10 +35,7 @@ pub fn main() !void {
 
     const allocator = gpa.allocator();
 
-    var threaded_io: std.Io.Threaded = .init(allocator, .{});
+    var app: App = .init;
-    defer threaded_io.deinit();
-
-    var app: App = .init(threaded_io.ioBasic(), .{});
     var renderer = zterm.Renderer.Buffered.init(allocator);
     defer renderer.deinit();
 
@@ -81,7 +78,7 @@ pub fn main() !void {
         }
 
         // NOTE returned errors should be propagated back to the application
-        container.handle(&app.model, event) catch |err| app.postEvent(.{
+        container.handle(event) catch |err| app.postEvent(.{
             .err = .{
                 .err = err,
                 .msg = "Container Event handling failed",
@@ -94,9 +91,9 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(&app.model, try renderer.resize());
+        container.resize(try renderer.resize());
-        container.reposition(&app.model, .{});
+        container.reposition(.{});
-        try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
+        try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }
 }
@@ -107,4 +104,4 @@ const log = std.log.scoped(.default);
 const std = @import("std");
 const assert = std.debug.assert;
 const zterm = @import("zterm");
-const App = zterm.App(struct {}, union(enum) {});
+const App = zterm.App(union(enum) {});

examples/layouts/mixed.zig

@@ -8,7 +8,7 @@ const QuitText = struct {
         };
     }
 
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
@@ -35,10 +35,7 @@ pub fn main() !void {
 
     const allocator = gpa.allocator();
 
-    var threaded_io: std.Io.Threaded = .init(allocator, .{});
+    var app: App = .init;
-    defer threaded_io.deinit();
-
-    var app: App = .init(threaded_io.ioBasic(), .{});
     var renderer = zterm.Renderer.Buffered.init(allocator);
     defer renderer.deinit();
 
@@ -97,7 +94,7 @@ pub fn main() !void {
         }
 
         // NOTE returned errors should be propagated back to the application
-        container.handle(&app.model, event) catch |err| app.postEvent(.{
+        container.handle(event) catch |err| app.postEvent(.{
             .err = .{
                 .err = err,
                 .msg = "Container Event handling failed",
@@ -110,9 +107,9 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(&app.model, try renderer.resize());
+        container.resize(try renderer.resize());
-        container.reposition(&app.model, .{});
+        container.reposition(.{});
-        try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
+        try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }
 }
@@ -123,4 +120,4 @@ const log = std.log.scoped(.default);
 const std = @import("std");
 const assert = std.debug.assert;
 const zterm = @import("zterm");
-const App = zterm.App(struct {}, union(enum) {});
+const App = zterm.App(union(enum) {});

examples/layouts/vertical.zig

@@ -8,7 +8,7 @@ const QuitText = struct {
         };
     }
 
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
@@ -35,10 +35,7 @@ pub fn main() !void {
 
     const allocator = gpa.allocator();
 
-    var threaded_io: std.Io.Threaded = .init(allocator, .{});
+    var app: App = .init;
-    defer threaded_io.deinit();
-
-    var app: App = .init(threaded_io.ioBasic(), .{});
     var renderer = zterm.Renderer.Buffered.init(allocator);
     defer renderer.deinit();
 
@@ -80,7 +77,7 @@ pub fn main() !void {
         }
 
         // NOTE returned errors should be propagated back to the application
-        container.handle(&app.model, event) catch |err| app.postEvent(.{
+        container.handle(event) catch |err| app.postEvent(.{
             .err = .{
                 .err = err,
                 .msg = "Container Event handling failed",
@@ -93,9 +90,9 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(&app.model, try renderer.resize());
+        container.resize(try renderer.resize());
-        container.reposition(&app.model, .{});
+        container.reposition(.{});
-        try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
+        try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }
 }
@@ -106,4 +103,4 @@ const log = std.log.scoped(.default);
 const std = @import("std");
 const assert = std.debug.assert;
 const zterm = @import("zterm");
-const App = zterm.App(struct {}, union(enum) {});
+const App = zterm.App(union(enum) {});

examples/styles/palette.zig

@@ -5,7 +5,7 @@ const QuitText = struct {
         return .{ .ptr = this, .vtable = &.{ .content = content } };
     }
 
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
@@ -32,10 +32,7 @@ pub fn main() !void {
 
     const allocator = gpa.allocator();
 
-    var threaded_io: std.Io.Threaded = .init(allocator, .{});
+    var app: App = .init;
-    defer threaded_io.deinit();
-
-    var app: App = .init(threaded_io.ioBasic(), .{});
     var renderer = zterm.Renderer.Buffered.init(allocator);
     defer renderer.deinit();
 
@@ -53,6 +50,7 @@ pub fn main() !void {
     var box = try App.Container.init(allocator, .{
         .layout = .{ .direction = .horizontal },
     }, .{});
+    defer box.deinit();
 
     inline for (std.meta.fields(zterm.Color)) |field| {
         if (field.value == 0) continue; // zterm.Color.default == 0 -> skip
@@ -75,7 +73,7 @@ pub fn main() !void {
             else => {},
         }
 
-        container.handle(&app.model, event) catch |err| app.postEvent(.{
+        container.handle(event) catch |err| app.postEvent(.{
             .err = .{
                 .err = err,
                 .msg = "Container Event handling failed",
@@ -88,9 +86,9 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(&app.model, try renderer.resize());
+        container.resize(try renderer.resize());
-        container.reposition(&app.model, .{});
+        container.reposition(.{});
-        try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
+        try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }
 }
@@ -101,4 +99,4 @@ const log = std.log.scoped(.default);
 const std = @import("std");
 const assert = std.debug.assert;
 const zterm = @import("zterm");
-const App = zterm.App(struct {}, union(enum) {});
+const App = zterm.App(union(enum) {});

examples/styles/text.zig

@@ -5,7 +5,7 @@ const QuitText = struct {
         return .{ .ptr = this, .vtable = &.{ .content = content } };
     }
 
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
@@ -24,109 +24,14 @@ const QuitText = struct {
     }
 };
 
-const TableText = struct {
-    pub fn element(this: *@This()) App.Element {
-        return .{
-            .ptr = this,
-            .vtable = &.{
-                .content = content,
-            },
-        };
-    }
-
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
-        _ = ctx;
-        _ = size;
-        var idx: usize = 0;
-        {
-            const text = "Normal ";
-            for (text) |cp| {
-                cells[idx].cp = cp;
-                idx += 1;
-            }
-        }
-        {
-            const text = "Bold   ";
-            for (text) |cp| {
-                cells[idx].cp = cp;
-                idx += 1;
-            }
-        }
-        {
-            const text = "Dim    ";
-            for (text) |cp| {
-                cells[idx].cp = cp;
-                idx += 1;
-            }
-        }
-        {
-            const text = "Italic ";
-            for (text) |cp| {
-                cells[idx].cp = cp;
-                idx += 1;
-            }
-        }
-        {
-            const text = "Underl ";
-            for (text) |cp| {
-                cells[idx].cp = cp;
-                idx += 1;
-            }
-        }
-        {
-            const text = "Blink  ";
-            for (text) |cp| {
-                cells[idx].cp = cp;
-                idx += 1;
-            }
-        }
-        {
-            const text = "Invert ";
-            for (text) |cp| {
-                cells[idx].cp = cp;
-                idx += 1;
-            }
-        }
-        {
-            const text = "Hidden ";
-            for (text) |cp| {
-                cells[idx].cp = cp;
-                idx += 1;
-            }
-        }
-        {
-            const text = "Strikethrough";
-            for (text) |cp| {
-                cells[idx].cp = cp;
-                idx += 1;
-            }
-        }
-    }
-};
-
 const TextStyles = struct {
     const text = "Example";
 
     pub fn element(this: *@This()) App.Element {
-        return .{
+        return .{ .ptr = this, .vtable = &.{ .content = content } };
-            .ptr = this,
-            .vtable = &.{
-                .minSize = minSize,
-                .content = content,
-            },
-        };
     }
 
-    fn minSize(ctx: *anyopaque, _: *const App.Model, size: zterm.Point) zterm.Point {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
-        _ = ctx;
-        _ = size;
-        return .{
-            .x = std.meta.fields(zterm.Style.Emphasis).len * TextStyles.text.len,
-            .y = (std.meta.fields(zterm.Color).len - 1) * (std.meta.fields(zterm.Color).len - 2),
-        };
-    }
-
-    fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
         @setEvalBranchQuota(10000);
         _ = ctx;
         assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
@@ -178,10 +83,7 @@ pub fn main() !void {
 
     const allocator = gpa.allocator();
 
-    var threaded_io: std.Io.Threaded = .init(allocator, .{});
+    var app: App = .init;
-    defer threaded_io.deinit();
-
-    var app: App = .init(threaded_io.ioBasic(), .{});
     var renderer = zterm.Renderer.Buffered.init(allocator);
     defer renderer.deinit();
 
@@ -192,43 +94,33 @@ pub fn main() !void {
 
     var container = try App.Container.init(allocator, .{
         .layout = .{
-            // .gap = 2,
+            .gap = 2,
             .padding = .{ .top = 5, .bottom = 3, .left = 3, .right = 3 },
-            .direction = .vertical,
         },
     }, element);
     defer container.deinit();
 
-    var table_head: TableText = .{};
+    var box = try App.Container.init(allocator, .{
-    try container.append(try .init(allocator, .{
-        .size = .{
-            .dim = .{ .y = 1 },
-            .grow = .horizontal,
-        },
-    }, table_head.element()));
-
-    var scrollable: App.Scrollable = .init(try .init(allocator, .{
         .layout = .{ .direction = .vertical },
-    }, text_styles.element()), .enabled(.white, true));
+        .size = .{
+            .dim = .{
+                .x = std.meta.fields(zterm.Style.Emphasis).len * TextStyles.text.len,
+                .y = (std.meta.fields(zterm.Color).len - 1) * (std.meta.fields(zterm.Color).len - 2),
+            },
+        },
+    }, text_styles.element());
+    defer box.deinit();
+
+    var scrollable: App.Scrollable = .init(box, .disabled);
     try container.append(try App.Container.init(allocator, .{}, scrollable.element()));
 
     try app.start();
     defer app.stop() catch |err| log.err("Failed to stop application: {any}", .{err});
 
-    // event loop
+    while (true) {
-    loop: while (true) {
+        const event = app.nextEvent();
-        // batch events since last iteration
+        log.debug("received event: {s}", .{@tagName(event)});
-        const len = blk: {
-            app.queue.poll();
-            app.queue.lock();
-            defer app.queue.unlock();
-            break :blk app.queue.len();
-        };
 
-        // handle events
-        for (0..len) |_| {
-            const event = app.queue.pop();
-            log.debug("handling event: {s}", .{@tagName(event)});
         // pre event handling
         switch (event) {
             .key => |key| if (key.eql(.{ .cp = 'c', .mod = .{ .ctrl = true } })) app.quit(),
@@ -236,7 +128,7 @@ pub fn main() !void {
             else => {},
         }
 
-            container.handle(&app.model, event) catch |err| app.postEvent(.{
+        container.handle(event) catch |err| app.postEvent(.{
             .err = .{
                 .err = err,
                 .msg = "Container Event handling failed",
@@ -245,14 +137,13 @@ pub fn main() !void {
 
         // post event handling
         switch (event) {
-                .quit => break :loop,
+            .quit => break,
             else => {},
         }
-        }
 
-        container.resize(&app.model, try renderer.resize());
+        container.resize(try renderer.resize());
-        container.reposition(&app.model, .{});
+        container.reposition(.{});
-        try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
+        try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }
 }
@@ -263,5 +154,4 @@ const log = std.log.scoped(.default);
 const std = @import("std");
 const assert = std.debug.assert;
 const zterm = @import("zterm");
-
+const App = zterm.App(union(enum) {});
-const App = zterm.App(struct {}, union(enum) {});

src/app.zig

@@ -12,45 +12,41 @@
 /// ```zig
 ///   const zterm = @import("zterm");
 ///   const App = zterm.App(
-///       struct {}, // empty model
+///       union(enum) {},
-///       union(enum) {}, // no additional user event's
 ///   );
 ///   // later on create an `App` instance and start the event loop
-///   var app: App = .init(io, .{}); // provide instance of the `std.Io` and `App` model that shall be used
+///   var app: App = .init;
 ///   try app.start();
-///   defer app.stop() catch unreachable; // does not clean-up the resources used in the model
+///   defer app.stop() catch unreachable;
 /// ```
-pub fn App(comptime M: type, comptime E: type) type {
+pub fn App(comptime E: type) type {
-    if (!isStruct(M)) @compileError("Provided model `M` for `App(comptime M: type, comptime E: type)` is not of type `struct`");
+    if (!isTaggedUnion(E)) {
-    if (!isTaggedUnion(E)) @compileError("Provided user event `E` for `App(comptime M: type, comptime E: type)` is not of type `union(enum)`.");
+        @compileError("Provided user event `E` for `App(comptime E: type)` is not of type `union(enum)`.");
+    }
     return struct {
-        io: std.Io,
-        model: Model,
         queue: Queue,
-        future: ?std.Io.Future(@typeInfo(@typeInfo(@TypeOf(run)).@"fn".return_type.?).error_union.error_set!void) = null,
+        thread: ?Thread = null,
+        quit_event: Thread.ResetEvent,
         termios: ?posix.termios = null,
         winch_registered: bool = false,
 
         // global variable for the registered handler for WINCH
         var handler_ctx: *anyopaque = undefined;
         /// registered WINCH handler to report resize events
-        fn handleWinch(_: std.os.linux.SIG) callconv(.c) void {
+        fn handleWinch(_: c_int) callconv(.C) void {
             const this: *@This() = @ptrCast(@alignCast(handler_ctx));
             // NOTE this does not have to be done if in-band resize events are supported
             // -> the signal might not work correctly when hosting the application over ssh!
             this.postEvent(.resize);
         }
 
-        pub fn init(io: std.Io, model: Model) @This() {
+        pub const init: @This() = .{
-            return .{
-                .io = io,
-                .model = model,
             .queue = .{},
+            .quit_event = .{},
         };
-        }
 
         pub fn start(this: *@This()) !void {
-            if (this.future) |_| return;
+            if (this.thread) |_| return;
 
             // post init event (as the very first element to be in the queue - event loop)
             this.postEvent(.init);
@@ -66,48 +62,46 @@ pub fn App(comptime M: type, comptime E: type) type {
                 this.winch_registered = true;
             }
 
-            this.future = this.io.async(run, .{this});
+            this.quit_event.reset();
+            this.thread = try Thread.spawn(.{}, @This().run, .{this});
 
             var termios: posix.termios = undefined;
             try terminal.enableRawMode(&termios);
             if (this.termios) |_| {} else this.termios = termios;
 
-            try terminal.enterAltScreen();
             try terminal.saveScreen();
+            try terminal.enterAltScreen();
             try terminal.hideCursor();
             try terminal.enableMouseSupport();
         }
 
         pub fn interrupt(this: *@This()) !void {
+            this.quit_event.set();
             try terminal.disableMouseSupport();
-            try terminal.restoreScreen();
             try terminal.exitAltScreen();
-            if (this.future) |*future| {
+            try terminal.restoreScreen();
-                future.cancel(this.io) catch {};
+            if (this.thread) |thread| {
-                this.future = null;
+                thread.join();
+                this.thread = null;
             }
         }
 
         pub fn stop(this: *@This()) !void {
             try this.interrupt();
-            if (this.termios) |termios| {
+            if (this.termios) |*termios| {
                 try terminal.disableMouseSupport();
                 try terminal.showCursor();
-                try terminal.resetCursor();
-                try terminal.restoreScreen();
-                try terminal.disableRawMode(&termios);
                 try terminal.exitAltScreen();
-                this.termios = null;
+                try terminal.disableRawMode(termios);
+                try terminal.restoreScreen();
             }
+            this.termios = null;
         }
 
         /// Quit the application loop.
-        /// This will cancel the internal input thread and post a **.quit** `Event`.
+        /// This will stop the internal input thread and post a **.quit** `Event`.
         pub fn quit(this: *@This()) void {
-            if (this.future) |*future| {
+            this.quit_event.set();
-                future.cancel(this.io) catch {};
-                this.future = null;
-            }
             this.postEvent(.quit);
         }
 
@@ -123,45 +117,13 @@ pub fn App(comptime M: type, comptime E: type) type {
 
         fn run(this: *@This()) !void {
             // thread to read user inputs
-            var buf: [512]u8 = undefined;
+            var buf: [256]u8 = undefined;
-            // NOTE set the `NONBLOCK` option for the stdin file, such that reading is not blocking!
-            {
-                // TODO is there a better way to do this through the `std.Io` interface?
-                var fl_flags = posix.fcntl(posix.STDIN_FILENO, posix.F.GETFL, 0) catch |err| switch (err) {
-                    error.FileBusy => unreachable,
-                    error.Locked => unreachable,
-                    error.PermissionDenied => unreachable,
-                    error.DeadLock => unreachable,
-                    error.LockedRegionLimitExceeded => unreachable,
-                    else => |e| return e,
-                };
-                fl_flags |= 1 << @bitOffsetOf(posix.system.O, "NONBLOCK");
-                _ = posix.fcntl(posix.STDIN_FILENO, posix.F.SETFL, fl_flags) catch |err| switch (err) {
-                    error.FileBusy => unreachable,
-                    error.Locked => unreachable,
-                    error.PermissionDenied => unreachable,
-                    error.DeadLock => unreachable,
-                    error.LockedRegionLimitExceeded => unreachable,
-                    else => |e| return e,
-                };
-            }
             while (true) {
-                this.io.checkCancel() catch break;
+                // FIX I still think that there is a race condition (I'm just waiting 'long' enough)
-                var remaining_bytes: usize = 0;
+                this.quit_event.timedWait(20 * std.time.ns_per_ms) catch {
-
+                    // FIX in case the queue is full -> the next user input should panic and quit the application? because something seems to clock up the event queue
-                // non-blocking read
+                    const read_bytes = try terminal.read(buf[0..]);
-                const read_bytes = terminal.read(buf[remaining_bytes..]) catch |err| switch (err) {
+                    // TODO `break` should not terminate the reading of the user inputs, but instead only the received faulty input!
-                    error.WouldBlock => {
-                        // wait a bit
-                        this.io.sleep(.fromMilliseconds(20), .awake) catch |e| switch (e) {
-                            error.Canceled => break,
-                            else => return e,
-                        };
-                        continue;
-                    },
-                    else => return err,
-                } + remaining_bytes;
-
                     // escape key presses
                     if (buf[0] == 0x1b and read_bytes > 1) {
                         switch (buf[1]) {
@@ -188,9 +150,9 @@ pub fn App(comptime M: type, comptime E: type) type {
                                 if (read_bytes < 3) continue;
 
                                 // We start iterating at index 2 to get past the '['
-                            const sequence: []u8 = blk: for (buf[2..], 2..) |b, i| {
+                                const sequence = for (buf[2..], 2..) |b, i| {
                                     switch (b) {
-                                    0x40...0xFF => break :blk buf[0 .. i + 1],
+                                        0x40...0xFF => break buf[0 .. i + 1],
                                         else => continue,
                                     }
                                 } else continue;
@@ -321,8 +283,7 @@ pub fn App(comptime M: type, comptime E: type) type {
                                         // const alt = button_mask & mouse_bits.alt > 0;
                                         // const ctrl = button_mask & mouse_bits.ctrl > 0;
 
-                                    this.postEvent(.{
+                                        const mouse: Mouse = .{
-                                        .mouse = .{
                                             .button = button,
                                             .x = px -| 1,
                                             .y = py -| 1,
@@ -332,8 +293,8 @@ pub fn App(comptime M: type, comptime E: type) type {
                                                 if (sequence[sequence.len - 1] == 'm') break :blk .release;
                                                 break :blk .press;
                                             },
-                                        },
+                                        };
-                                    });
+                                        this.postEvent(.{ .mouse = mouse });
                                     },
                                     'c' => {
                                         // Primary DA (CSI ? Pm c)
@@ -415,25 +376,24 @@ pub fn App(comptime M: type, comptime E: type) type {
                             },
                             0x7f => .{ .cp = input.Backspace },
                             else => {
-                            var len = read_bytes;
+                                var iter = code_point.Iterator{ .bytes = buf[0..read_bytes] };
-                            while (!std.unicode.utf8ValidateSlice(buf[0..len])) len -= 1;
+                                while (iter.next()) |cp| this.postEvent(.{ .key = .{ .cp = cp.code } });
-                            remaining_bytes = read_bytes - len;
-                            var iter: std.unicode.Utf8Iterator = .{ .bytes = buf[0..len], .i = 0 };
-                            while (iter.nextCodepoint()) |cp| this.postEvent(.{ .key = .{ .cp = cp } });
                                 continue;
                             },
                         };
                         this.postEvent(.{ .key = key });
                     }
+                    continue;
+                };
+                break;
             }
         }
 
         pub fn panic_handler(msg: []const u8, _: ?*std.builtin.StackTrace, ret_addr: ?usize) noreturn {
             terminal.disableMouseSupport() catch {};
+            terminal.exitAltScreen() catch {};
             terminal.showCursor() catch {};
-            terminal.resetCursor() catch {};
+            var termios: posix.termios = .{
-            terminal.restoreScreen() catch {};
-            terminal.disableRawMode(&.{
                 .iflag = .{},
                 .lflag = .{},
                 .cflag = .{},
@@ -442,25 +402,23 @@ pub fn App(comptime M: type, comptime E: type) type {
                 .line = 0,
                 .ispeed = undefined,
                 .ospeed = undefined,
-            }) catch {};
+            };
-            terminal.exitAltScreen() catch {};
+            terminal.disableRawMode(&termios) catch {};
+            terminal.restoreScreen() catch {};
             std.debug.defaultPanic(msg, ret_addr);
         }
 
         const element = @import("element.zig");
-        pub const Model = M;
         pub const Event = mergeTaggedUnions(event.SystemEvent, E);
-        pub const Container = @import("container.zig").Container(Model, Event);
+        pub const Container = @import("container.zig").Container(Event);
-        pub const Element = element.Element(Model, Event);
+        pub const Element = element.Element(Event);
-        pub const Alignment = element.Alignment(Model, Event);
+        pub const Alignment = element.Alignment(Event);
-        pub const Button = element.Button(Model, Event, Queue);
+        pub const Button = element.Button(Event, Queue);
-        pub const TextField = element.TextField(Model, Event);
+        pub const Exec = element.Exec(Event, Queue);
-        pub const Input = element.Input(Model, Event, Queue);
+        pub const Input = element.Input(Event, Queue);
-        pub const Progress = element.Progress(Model, Event, Queue);
+        pub const Progress = element.Progress(Event, Queue);
-        pub const RadioButton = element.RadioButton(Model, Event);
+        pub const Scrollable = element.Scrollable(Event);
-        pub const Scrollable = element.Scrollable(Model, Event);
+        pub const Queue = queue.Queue(Event, 256);
-        pub const Selection = element.Selection(Model, Event);
-        pub const Queue = queue.Queue(Event, 512);
     };
 }
 
@@ -472,13 +430,13 @@ const fmt = std.fmt;
 const posix = std.posix;
 const Thread = std.Thread;
 const assert = std.debug.assert;
+const code_point = @import("code_point");
 const event = @import("event.zig");
 const input = @import("input.zig");
 const terminal = @import("terminal.zig");
 const queue = @import("queue.zig");
 const mergeTaggedUnions = event.mergeTaggedUnions;
 const isTaggedUnion = event.isTaggedUnion;
-const isStruct = event.isStruct;
 const Mouse = input.Mouse;
 const Key = input.Key;
 const Point = @import("point.zig").Point;

src/cell.zig

@@ -1,5 +1,6 @@
 //! Cell type containing content and formatting for each character in the terminal screen.
 
+// TODO embrace `zg` dependency more due to utf-8 encoding
 cp: u21 = ' ',
 style: Style = .{ .emphasis = &.{} },
 
@@ -12,7 +13,7 @@ pub fn reset(this: *Cell) void {
     this.cp = ' ';
 }
 
-pub fn value(this: Cell, writer: *std.Io.Writer) !void {
+pub fn value(this: Cell, writer: anytype) !void {
     try this.style.value(writer, this.cp);
 }
 
@@ -25,18 +26,20 @@ test "ascii styled text" {
         .{ .cp = 'Y', .style = .{ .fg = .green, .bg = .grey, .emphasis = &.{} } },
         .{ .cp = 'v', .style = .{ .emphasis = &.{ .bold, .underline } } },
         .{ .cp = 'e', .style = .{ .emphasis = &.{.italic} } },
-        .{ .cp = 's', .style = .{ .fg = .lightgreen, .bg = .black, .emphasis = &.{.underline} } },
+        .{ .cp = 's', .style = .{ .fg = .light_green, .bg = .black, .emphasis = &.{.underline} } },
     };
 
-    var writer = std.Io.Writer.Allocating.init(std.testing.allocator);
+    var string = std.ArrayList(u8).init(std.testing.allocator);
-    defer writer.deinit();
+    defer string.deinit();
+
+    const writer = string.writer();
     for (cells) |cell| {
-        try cell.value(&writer.writer);
+        try cell.value(writer);
     }
     try std.testing.expectEqualSlices(
         u8,
         "\x1b[38;5;10;48;5;8;59mY\x1b[0m\x1b[39;49;59;1;4mv\x1b[0m\x1b[39;49;59;3me\x1b[0m\x1b[38;5;2;48;5;16;59;4ms\x1b[0m",
-        writer.writer.buffer[0..writer.writer.end],
+        string.items,
     );
 }
 
@@ -45,17 +48,19 @@ test "utf-8 styled text" {
         .{ .cp = '╭', .style = .{ .fg = .green, .bg = .grey, .emphasis = &.{} } },
         .{ .cp = '─', .style = .{ .emphasis = &.{} } },
         .{ .cp = '┄', .style = .{ .emphasis = &.{} } },
-        .{ .cp = '┘', .style = .{ .fg = .lightgreen, .bg = .black, .emphasis = &.{.underline} } },
+        .{ .cp = '┘', .style = .{ .fg = .light_green, .bg = .black, .emphasis = &.{.underline} } },
     };
 
-    var writer = std.Io.Writer.Allocating.init(std.testing.allocator);
+    var string = std.ArrayList(u8).init(std.testing.allocator);
-    defer writer.deinit();
+    defer string.deinit();
+
+    const writer = string.writer();
     for (cells) |cell| {
-        try cell.value(&writer.writer);
+        try cell.value(writer);
     }
     try std.testing.expectEqualSlices(
         u8,
         "\x1b[38;5;10;48;5;8;59m╭\x1b[0m\x1b[39;49;59m─\x1b[0m\x1b[39;49;59m┄\x1b[0m\x1b[38;5;2;48;5;16;59;4m┘\x1b[0m",
-        writer.writer.buffer[0..writer.writer.end],
+        string.items,
     );
 }

src/color.zig

@@ -1,13 +1,13 @@
 pub const Color = enum(u8) {
     default = 0,
     black = 16,
-    lightred = 1,
+    light_red = 1,
-    lightgreen,
+    light_green,
-    lightyellow,
+    light_yellow,
-    lightblue,
+    light_blue,
-    lightmagenta,
+    light_magenta,
-    lightcyan,
+    light_cyan,
-    lightgrey,
+    light_grey,
     grey,
     red,
     green,
@@ -18,21 +18,24 @@ pub const Color = enum(u8) {
     white,
     // TODO add further colors as described in https://gist.github.com/ConnerWill/d4b6c776b509add763e17f9f113fd25b # Color / Graphics Mode - 256 Colors
 
-    pub inline fn write(this: Color, writer: *std.Io.Writer, comptime coloring: enum { fg, bg, ul }) !void {
+    // TODO might be useful to use the std.ascii stuff!
+
+    pub inline fn write(this: Color, writer: anytype, comptime coloring: enum { fg, bg, ul }) !void {
         if (this == .default) {
             switch (coloring) {
-                .fg => try writer.printAscii("39", .{}),
+                .fg => try format(writer, "39", .{}),
-                .bg => try writer.printAscii("49", .{}),
+                .bg => try format(writer, "49", .{}),
-                .ul => try writer.printAscii("59", .{}),
+                .ul => try format(writer, "59", .{}),
             }
         } else {
             switch (coloring) {
-                .fg => try writer.print("38;5;{d}", .{@intFromEnum(this)}),
+                .fg => try format(writer, "38;5;{d}", .{@intFromEnum(this)}),
-                .bg => try writer.print("48;5;{d}", .{@intFromEnum(this)}),
+                .bg => try format(writer, "48;5;{d}", .{@intFromEnum(this)}),
-                .ul => try writer.print("58;5;{d}", .{@intFromEnum(this)}),
+                .ul => try format(writer, "58;5;{d}", .{@intFromEnum(this)}),
             }
         }
     }
 };
 
 const std = @import("std");
+const format = std.fmt.format;

src/container.zig

@@ -1,6 +1,3 @@
-// FIX known issues:
-// - hold fewer instances of the `Allocator`
-
 /// Border configuration struct
 pub const Border = packed struct {
     /// Color to use for the border
@@ -80,9 +77,8 @@ pub const Border = packed struct {
     test "all sides" {
         const event = @import("event.zig");
         const testing = @import("testing.zig");
-        const Model = struct {};
 
-        var container: Container(Model, event.SystemEvent) = try .init(std.testing.allocator, .{
+        var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
             .border = .{
                 .color = .green,
                 .sides = .all,
@@ -93,15 +89,14 @@ pub const Border = packed struct {
         try testing.expectContainerScreen(.{
             .y = 20,
             .x = 30,
-        }, @TypeOf(container), &container, Model, @import("test/container/border.all.zon"));
+        }, &container, @import("test/container/border.all.zon"));
     }
 
     test "vertical sides" {
         const event = @import("event.zig");
         const testing = @import("testing.zig");
-        const Model = struct {};
 
-        var container: Container(Model, event.SystemEvent) = try .init(std.testing.allocator, .{
+        var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
             .border = .{
                 .color = .green,
                 .sides = .vertical,
@@ -112,15 +107,14 @@ pub const Border = packed struct {
         try testing.expectContainerScreen(.{
             .y = 20,
             .x = 30,
-        }, @TypeOf(container), &container, Model, @import("test/container/border.vertical.zon"));
+        }, &container, @import("test/container/border.vertical.zon"));
     }
 
     test "horizontal sides" {
         const event = @import("event.zig");
         const testing = @import("testing.zig");
-        const Model = struct {};
 
-        var container: Container(Model, event.SystemEvent) = try .init(std.testing.allocator, .{
+        var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
             .border = .{
                 .color = .green,
                 .sides = .horizontal,
@@ -131,7 +125,7 @@ pub const Border = packed struct {
         try testing.expectContainerScreen(.{
             .y = 20,
             .x = 30,
-        }, @TypeOf(container), &container, Model, @import("test/container/border.horizontal.zon"));
+        }, &container, @import("test/container/border.horizontal.zon"));
     }
 };
 
@@ -163,9 +157,8 @@ pub const Rectangle = packed struct {
     test "fill color overwrite parent fill" {
         const event = @import("event.zig");
         const testing = @import("testing.zig");
-        const Model = struct {};
 
-        var container: Container(Model, event.SystemEvent) = try .init(std.testing.allocator, .{
+        var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
             .rectangle = .{ .fill = .green },
         }, .{});
         try container.append(try .init(std.testing.allocator, .{
@@ -177,15 +170,14 @@ pub const Rectangle = packed struct {
         try testing.expectContainerScreen(.{
             .y = 20,
             .x = 30,
-        }, @TypeOf(container), &container, Model, @import("test/container/rectangle_with_parent_fill_without_padding.zon"));
+        }, &container, @import("test/container/rectangle_with_parent_fill_without_padding.zon"));
     }
 
     test "fill color padding to show parent fill" {
         const event = @import("event.zig");
         const testing = @import("testing.zig");
-        const Model = struct {};
 
-        var container: Container(Model, event.SystemEvent) = try .init(std.testing.allocator, .{
+        var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
             .layout = .{
                 .padding = .all(2),
             },
@@ -200,15 +192,14 @@ pub const Rectangle = packed struct {
         try testing.expectContainerScreen(.{
             .y = 20,
             .x = 30,
-        }, @TypeOf(container), &container, Model, @import("test/container/rectangle_with_parent_padding.zon"));
+        }, &container, @import("test/container/rectangle_with_parent_padding.zon"));
     }
 
     test "fill color padding to show parent fill (negative padding)" {
         const event = @import("event.zig");
         const testing = @import("testing.zig");
-        const Model = struct {};
 
-        var container: Container(Model, event.SystemEvent) = try .init(std.testing.allocator, .{
+        var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
             .layout = .{
                 .padding = .{
                     .top = -18,
@@ -228,15 +219,14 @@ pub const Rectangle = packed struct {
         try testing.expectContainerScreen(.{
             .y = 20,
             .x = 30,
-        }, @TypeOf(container), &container, Model, @import("test/container/rectangle_with_parent_padding.zon"));
+        }, &container, @import("test/container/rectangle_with_parent_padding.zon"));
     }
 
     test "fill color spacer with padding" {
         const event = @import("event.zig");
         const testing = @import("testing.zig");
-        const Model = struct {};
 
-        var container: Container(Model, event.SystemEvent) = try .init(std.testing.allocator, .{
+        var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
             .rectangle = .{
                 .fill = .black,
             },
@@ -257,15 +247,14 @@ pub const Rectangle = packed struct {
         try testing.expectContainerScreen(.{
             .y = 20,
             .x = 30,
-        }, @TypeOf(container), &container, Model, @import("test/container/rectangle_with_padding.zon"));
+        }, &container, @import("test/container/rectangle_with_padding.zon"));
     }
 
     test "fill color with gap" {
         const event = @import("event.zig");
         const testing = @import("testing.zig");
-        const Model = struct {};
 
-        var container: Container(Model, event.SystemEvent) = try .init(std.testing.allocator, .{
+        var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
             .rectangle = .{
                 .fill = .black,
             },
@@ -289,15 +278,14 @@ pub const Rectangle = packed struct {
         try testing.expectContainerScreen(.{
             .y = 20,
             .x = 30,
-        }, @TypeOf(container), &container, Model, @import("test/container/rectangle_with_gap.zon"));
+        }, &container, @import("test/container/rectangle_with_gap.zon"));
     }
 
     test "fill color with separator" {
         const event = @import("event.zig");
         const testing = @import("testing.zig");
-        const Model = struct {};
 
-        var container: Container(Model, event.SystemEvent) = try .init(std.testing.allocator, .{
+        var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
             .rectangle = .{
                 .fill = .black,
             },
@@ -322,7 +310,7 @@ pub const Rectangle = packed struct {
         try testing.expectContainerScreen(.{
             .y = 20,
             .x = 30,
-        }, @TypeOf(container), &container, Model, @import("test/container/rectangle_with_separator.zon"));
+        }, &container, @import("test/container/rectangle_with_separator.zon"));
     }
 };
 
@@ -412,9 +400,8 @@ pub const Layout = packed struct {
     test "separator without gaps" {
         const event = @import("event.zig");
         const testing = @import("testing.zig");
-        const Model = struct {};
 
-        var container: Container(Model, event.SystemEvent) = try .init(std.testing.allocator, .{
+        var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
             .layout = .{
                 .separator = .{
                     .enabled = true,
@@ -428,15 +415,14 @@ pub const Layout = packed struct {
         try testing.expectContainerScreen(.{
             .y = 20,
             .x = 30,
-        }, @TypeOf(container), &container, Model, @import("test/container/separator_no_gaps.zon"));
+        }, &container, @import("test/container/separator_no_gaps.zon"));
     }
 
     test "separator without gaps with padding" {
         const event = @import("event.zig");
         const testing = @import("testing.zig");
-        const Model = struct {};
 
-        var container: Container(Model, event.SystemEvent) = try .init(std.testing.allocator, .{
+        var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
             .layout = .{
                 .padding = .all(1),
                 .separator = .{
@@ -451,15 +437,14 @@ pub const Layout = packed struct {
         try testing.expectContainerScreen(.{
             .y = 20,
             .x = 30,
-        }, @TypeOf(container), &container, Model, @import("test/container/separator_no_gaps_with_padding.zon"));
+        }, &container, @import("test/container/separator_no_gaps_with_padding.zon"));
     }
 
     test "separator(2x) without gaps" {
         const event = @import("event.zig");
         const testing = @import("testing.zig");
-        const Model = struct {};
 
-        var container: Container(Model, event.SystemEvent) = try .init(std.testing.allocator, .{
+        var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
             .layout = .{
                 .direction = .vertical,
                 .separator = .{
@@ -476,15 +461,14 @@ pub const Layout = packed struct {
         try testing.expectContainerScreen(.{
             .y = 20,
             .x = 30,
-        }, @TypeOf(container), &container, Model, @import("test/container/separator_2x_no_gaps.zon"));
+        }, &container, @import("test/container/separator_2x_no_gaps.zon"));
     }
 
     test "separator(2x) with border(all)" {
         const event = @import("event.zig");
         const testing = @import("testing.zig");
-        const Model = struct {};
 
-        var container: Container(Model, event.SystemEvent) = try .init(std.testing.allocator, .{
+        var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
             .border = .{
                 .color = .red,
                 .sides = .all,
@@ -504,15 +488,14 @@ pub const Layout = packed struct {
         try testing.expectContainerScreen(.{
             .y = 20,
             .x = 30,
-        }, @TypeOf(container), &container, Model, @import("test/container/separator_2x_no_gaps_with_border.zon"));
+        }, &container, @import("test/container/separator_2x_no_gaps_with_border.zon"));
     }
 
     test "separator(2x) with border(all) and padding(all(1))" {
         const event = @import("event.zig");
         const testing = @import("testing.zig");
-        const Model = struct {};
 
-        var container: Container(Model, event.SystemEvent) = try .init(std.testing.allocator, .{
+        var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
             .border = .{
                 .color = .red,
                 .sides = .all,
@@ -533,15 +516,14 @@ pub const Layout = packed struct {
         try testing.expectContainerScreen(.{
             .y = 20,
             .x = 30,
-        }, @TypeOf(container), &container, Model, @import("test/container/separator_2x_no_gaps_with_padding.zon"));
+        }, &container, @import("test/container/separator_2x_no_gaps_with_padding.zon"));
     }
 
     test "separator(2x) with border(all) and gap" {
         const event = @import("event.zig");
         const testing = @import("testing.zig");
-        const Model = struct {};
 
-        var container: Container(Model, event.SystemEvent) = try .init(std.testing.allocator, .{
+        var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
             .border = .{
                 .color = .red,
                 .sides = .all,
@@ -562,15 +544,14 @@ pub const Layout = packed struct {
         try testing.expectContainerScreen(.{
             .y = 20,
             .x = 30,
-        }, @TypeOf(container), &container, Model, @import("test/container/separator_2x_with_gaps_with_border.zon"));
+        }, &container, @import("test/container/separator_2x_with_gaps_with_border.zon"));
     }
 
     test "separator(2x) with border(all) and gap and padding" {
         const event = @import("event.zig");
         const testing = @import("testing.zig");
-        const Model = struct {};
 
-        var container: Container(Model, event.SystemEvent) = try .init(std.testing.allocator, .{
+        var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
             .border = .{
                 .color = .red,
                 .sides = .all,
@@ -592,7 +573,7 @@ pub const Layout = packed struct {
         try testing.expectContainerScreen(.{
             .y = 20,
             .x = 30,
-        }, @TypeOf(container), &container, Model, @import("test/container/separator_2x_with_gaps_with_border_with_padding.zon"));
+        }, &container, @import("test/container/separator_2x_with_gaps_with_border_with_padding.zon"));
     }
 };
 
@@ -607,10 +588,10 @@ pub const Size = packed struct {
     } = .both,
 };
 
-pub fn Container(Model: type, Event: type) type {
+pub fn Container(comptime Event: type) type {
     if (!isTaggedUnion(Event)) @compileError("Provided user event `Event` for `Container(comptime Event: type)`");
 
-    const Element = @import("element.zig").Element(Model, Event);
+    const Element = @import("element.zig").Element(Event);
     return struct {
         allocator: Allocator,
         origin: Point,
@@ -641,24 +622,23 @@ pub fn Container(Model: type, Event: type) type {
                 .size = .{},
                 .properties = properties,
                 .element = element,
-                .elements = try std.ArrayList(@This()).initCapacity(allocator, 2),
+                .elements = std.ArrayList(@This()).init(allocator),
             };
         }
 
-        pub fn deinit(this: *@This()) void {
+        pub fn deinit(this: *const @This()) void {
             for (this.elements.items) |*element| element.deinit();
-            this.elements.deinit(this.allocator);
+            this.elements.deinit();
-            this.element.deinit();
         }
 
         pub fn append(this: *@This(), element: @This()) !void {
-            try this.elements.append(this.allocator, element);
+            try this.elements.append(element);
         }
 
-        pub fn reposition(this: *@This(), model: *const Model, origin: Point) void {
+        pub fn reposition(this: *@This(), origin: Point) void {
             const layout = this.properties.layout;
             this.origin = origin;
-            this.element.reposition(model, origin);
+            this.element.reposition(origin);
 
             var offset = origin.add(.{
                 .x = Layout.getAbsolutePadding(layout.padding.left, this.size.x),
@@ -670,7 +650,7 @@ pub fn Container(Model: type, Event: type) type {
             if (sides.top) offset.y += 1;
 
             for (this.elements.items) |*child| {
-                child.reposition(model, offset);
+                child.reposition(offset);
 
                 switch (layout.direction) {
                     .horizontal => offset.x += child.size.x + layout.gap,
@@ -685,7 +665,7 @@ pub fn Container(Model: type, Event: type) type {
         }
 
         /// Resize all fit sized `Containers` to the necessary size required by its child elements.
-        fn fit_resize(this: *@This(), model: *const Model) Point {
+        fn fit_resize(this: *@This()) Point {
             // NOTE this is supposed to be a simple and easy to understand algorithm, there are currently no optimizations done
             const layout = this.properties.layout;
             var size: Point = switch (layout.direction) {
@@ -710,7 +690,7 @@ pub fn Container(Model: type, Event: type) type {
             };
 
             for (this.elements.items) |*child| {
-                const child_size = child.fit_resize(model);
+                const child_size = child.fit_resize();
                 switch (layout.direction) {
                     .horizontal => {
                         size.x += child_size.x;
@@ -723,29 +703,24 @@ pub fn Container(Model: type, Event: type) type {
                 }
             }
 
-            size = this.minSize(model, size);
             // assign currently calculated size
             this.size = switch (this.properties.size.grow) {
-                .both => .max(size, this.properties.size.dim),
+                .both => Point.max(size, this.properties.size.dim),
-                .fixed => blk: {
+                .fixed => this.properties.size.dim,
-                    assert(this.properties.size.dim.x > 0 or size.x > 0);
+                .horizontal => .{
-                    assert(this.properties.size.dim.y > 0 or size.y > 0);
+                    .x = @max(size.x, this.properties.size.dim.x),
-                    break :blk .max(size, this.properties.size.dim);
+                    .y = this.properties.size.dim.y,
                 },
-                .horizontal => blk: {
+                .vertical => .{
-                    assert(this.properties.size.dim.y > 0 or size.y > 0);
+                    .x = this.properties.size.dim.x,
-                    break :blk .max(size, this.properties.size.dim);
+                    .y = @max(size.y, this.properties.size.dim.y),
-                },
-                .vertical => blk: {
-                    assert(this.properties.size.dim.x > 0 or size.x > 0);
-                    break :blk .max(size, this.properties.size.dim);
                 },
             };
             return this.size;
         }
 
         /// growable implicitly requires the root `Container` to have a set a size property to the size of the available terminal screen
-        fn grow_resize(this: *@This(), model: *const Model, max_size: Point) void {
+        fn grow_resize(this: *@This(), max_size: Point) void {
             const layout = this.properties.layout;
             var remainder = switch (layout.direction) {
                 .horizontal => max_size.x -| (Layout.getAbsolutePadding(layout.padding.left, this.size.x) + Layout.getAbsolutePadding(layout.padding.right, this.size.x)),
@@ -887,49 +862,31 @@ pub fn Container(Model: type, Event: type) type {
                 }
             }
 
-            this.element.resize(model, this.size);
+            this.element.resize(this.size);
-            for (this.elements.items) |*child| child.grow_resize(model, child.size);
+            for (this.elements.items) |*child| child.grow_resize(child.size);
         }
 
-        pub fn resize(this: *@This(), model: *const Model, size: Point) void {
+        pub fn resize(this: *@This(), size: Point) void {
             // NOTE assume that this function is only called for the root `Container`
             this.size = size;
-            const fit_size = this.fit_resize(model);
+            const fit_size = this.fit_resize();
-            this.size = switch (this.properties.size.grow) {
+            // if (fit_size.y > size.y or fit_size.x > size.x) @panic("error: cannot render in available space");
-                .both => .max(size, fit_size),
+            switch (this.properties.size.grow) {
-                .fixed => fit_size,
+                .both => this.size = Point.max(size, fit_size),
-                .horizontal => .{
+                .fixed => {},
+                .horizontal => this.size = .{
                     .x = @max(size.x, fit_size.x),
                     .y = size.y,
                 },
-                .vertical => .{
+                .vertical => this.size = .{
                     .x = size.x,
                     .y = @max(size.y, fit_size.y),
                 },
-            };
+            }
-            this.grow_resize(model, this.size);
+            this.grow_resize(this.size);
         }
 
-        pub fn minSize(this: *const @This(), model: *const Model, size: Point) Point {
+        pub fn handle(this: *const @This(), event: Event) !void {
-            var min_size: Point = .{};
-            for (this.elements.items) |*child| {
-                const child_size = child.minSize(model, child.properties.size.dim);
-                min_size = switch (this.properties.layout.direction) {
-                    .horizontal => .{
-                        .x = child_size.x + min_size.x,
-                        .y = @max(child_size.y, min_size.y),
-                    },
-                    .vertical => .{
-                        .x = @max(child_size.x, min_size.x),
-                        .y = child_size.y + min_size.y,
-                    },
-                };
-            }
-            const element_size = this.element.minSize(model, size);
-            return .max(element_size, min_size);
-        }
-
-        pub fn handle(this: *const @This(), model: *Model, event: Event) !void {
             switch (event) {
                 .mouse => |mouse| if (mouse.in(this.origin, this.size)) {
                     // the element receives the mouse event with relative position
@@ -937,19 +894,17 @@ pub fn Container(Model: type, Event: type) type {
                     var relative_mouse: input.Mouse = mouse;
                     relative_mouse.x -= this.origin.x;
                     relative_mouse.y -= this.origin.y;
-                    try this.element.handle(model, .{ .mouse = relative_mouse });
+                    try this.element.handle(.{ .mouse = relative_mouse });
+                    for (this.elements.items) |*element| try element.handle(event);
                 },
-                .bell => {
+                else => {
-                    // ring the terminal bell and do not propagate the event any further
+                    try this.element.handle(event);
-                    _ = try terminal.ringBell();
+                    for (this.elements.items) |*element| try element.handle(event);
-                    return;
                 },
-                else => try this.element.handle(model, event),
             }
-            for (this.elements.items) |*element| try element.handle(model, event);
         }
 
-        pub fn content(this: *const @This(), model: *const Model) ![]Cell {
+        pub fn content(this: *const @This()) ![]Cell {
             if (this.size.x == 0 or this.size.y == 0) return Error.TooSmall;
 
             const cells = try this.allocator.alloc(Cell, @as(usize, this.size.x) * @as(usize, this.size.y));
@@ -960,7 +915,7 @@ pub fn Container(Model: type, Event: type) type {
             this.properties.border.content(cells, this.size);
             this.properties.rectangle.content(cells, this.size);
 
-            try this.element.content(model, cells, this.size);
+            try this.element.content(cells, this.size);
 
             // DEBUG render corresponding corners (except top left) of this `Container` *red*
             if (comptime build_options.debug) {
@@ -990,7 +945,6 @@ const assert = std.debug.assert;
 const Allocator = std.mem.Allocator;
 const build_options = @import("build_options");
 const input = @import("input.zig");
-const terminal = @import("terminal.zig");
 const isTaggedUnion = @import("event.zig").isTaggedUnion;
 const Cell = @import("cell.zig");
 const Color = @import("color.zig").Color;
@@ -1005,9 +959,8 @@ test {
 test "Container Fixed and Grow Size Vertical" {
     const event = @import("event.zig");
     const testing = @import("testing.zig");
-    const Model = struct {};
 
-    var container: Container(Model, event.SystemEvent) = try .init(std.testing.allocator, .{
+    var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
         .layout = .{ .direction = .vertical },
     }, .{});
     try container.append(try .init(std.testing.allocator, .{
@@ -1025,15 +978,14 @@ test "Container Fixed and Grow Size Vertical" {
     try testing.expectContainerScreen(.{
         .y = 20,
         .x = 30,
-    }, @TypeOf(container), &container, Model, @import("test/container/fixed_grow_vertical.zon"));
+    }, &container, @import("test/container/fixed_grow_vertical.zon"));
 }
 
 test "Container Fixed and Grow Size Horizontal" {
     const event = @import("event.zig");
     const testing = @import("testing.zig");
-    const Model = struct {};
 
-    var container: Container(Model, event.SystemEvent) = try .init(std.testing.allocator, .{}, .{});
+    var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{}, .{});
     try container.append(try .init(std.testing.allocator, .{
         .size = .{
             .dim = .{ .x = 5 },
@@ -1049,5 +1001,5 @@ test "Container Fixed and Grow Size Horizontal" {
     try testing.expectContainerScreen(.{
         .y = 20,
         .x = 30,
-    }, @TypeOf(container), &container, Model, @import("test/container/fixed_grow_horizontal.zon"));
+    }, &container, @import("test/container/fixed_grow_horizontal.zon"));
 }

src/ctlseqs.zig

@@ -50,7 +50,6 @@ pub const home = "\x1b[H";
 pub const cup = "\x1b[{d};{d}H";
 pub const hide_cursor = "\x1b[?25l";
 pub const show_cursor = "\x1b[?25h";
-pub const reset_cursor_shape = "\x1b[0 q";
 pub const cursor_shape = "\x1b[{d} q";
 pub const ri = "\x1bM";
 pub const ind = "\n";
@@ -140,6 +139,5 @@ pub const osc10_reset = "\x1b]110\x1b\\"; // reset fg to terminal default
 pub const osc11_query = "\x1b]11;?\x1b\\"; // bg
 pub const osc11_set = "\x1b]11;rgb:{x:0>2}{x:0>2}/{x:0>2}{x:0>2}/{x:0>2}{x:0>2}\x1b\\"; // set default terminal bg
 pub const osc11_reset = "\x1b]111\x1b\\"; // reset bg to terminal default
-pub const osc12_set = "\x1b]12;{s}\x1b\\"; // set the cursor color through the name of the 8 base colors!
 pub const osc12_query = "\x1b]12;?\x1b\\"; // cursor color
 pub const osc12_reset = "\x1b]112\x1b\\"; // reset cursor to terminal default

src/event.zig

@@ -9,13 +9,7 @@ pub const SystemEvent = union(enum) {
     /// Quit event to signify the end of the event loop (rendering should stop afterwards)
     quit,
     /// Resize event to signify that the application should re-draw to resize
-    ///
-    /// Usually no `Container` nor `Element` should act on that event, as it
-    /// only serves for event based loops to force a re-draw with a new `Event`.
     resize,
-    /// Ring the terminal bell to notify the user. This `Event` is handled by
-    /// every `Container` and will not be passed through the container tree.
-    bell,
     /// Error event to notify other containers about a recoverable error
     err: struct {
         /// actual error
@@ -27,110 +21,76 @@ pub const SystemEvent = union(enum) {
     key: Key,
     /// Mouse input event
     mouse: Mouse,
-    /// Focus event indicating that the application has gained the focus of the user
+    /// Focus event for mouse interaction
+    /// TODO this should instead be a union with a `Size` to derive which container / element the focus meant for
     focus: bool,
+    /// Exit event for a completed `Exec` with the associated pid. Fired and handled by `Exec` `Element`s.
+    exited: std.posix.pid_t,
 };
 
-/// Merge the two provided `union(enum)` `A` and `B` to a tagged union containing all fields of both tagged unions in `comptime`.
-/// Declarations are not supported for `comptime` created types, see https://github.com/ziglang/zig/issues/6709 for details.
 pub fn mergeTaggedUnions(comptime A: type, comptime B: type) type {
-    // TODO maybe it makes sense to have a nested tagged union type (i.e. system: union(enum) and event: union(enum))
+    if (!isTaggedUnion(A) or !isTaggedUnion(B)) {
-    // - allows re-definition of system / built-in events
+        @compileError("Both types for merging tagged unions need to be of type `union(enum)`.");
-    // - clearly shows which events are system / built-in ones and which are user defined events
+    }
-    // - the memory footprint for the nesting is not really harmful
-    if (!isTaggedUnion(A) or !isTaggedUnion(B)) @compileError("Both types for merging tagged unions need to be of type `union(enum)`.");
-
     const a_fields = @typeInfo(A).@"union".fields;
     const a_fields_tag = @typeInfo(A).@"union".tag_type.?;
     const a_enum_fields = @typeInfo(a_fields_tag).@"enum".fields;
     const b_fields = @typeInfo(B).@"union".fields;
     const b_fields_tag = @typeInfo(B).@"union".tag_type.?;
     const b_enum_fields = @typeInfo(b_fields_tag).@"enum".fields;
-    var field_names: [a_fields.len + b_fields.len][:0]const u8 = undefined;
+    var fields: [a_fields.len + b_fields.len]std.builtin.Type.UnionField = undefined;
-    var field_types: [a_fields.len + b_fields.len]type = undefined;
+    var enum_fields: [a_fields.len + b_fields.len]std.builtin.Type.EnumField = undefined;
-    var field_attributes: [a_fields.len + b_fields.len]std.builtin.Type.UnionField.Attributes = undefined;
-    var enum_names: [a_fields.len + b_fields.len][:0]const u8 = undefined;
-    const UEnumSize = blk: {
-        const total_size = a_fields.len + b_fields.len;
-        break :blk switch (total_size) {
-            1...2 => u1,
-            3...4 => u2,
-            5...8 => u4,
-            9...16 => u4,
-            17...32 => u5,
-            33...64 => u6,
-            65...128 => u7,
-            129...256 => u8,
-            else => u16, // should suffice
-        };
-    };
-    var enum_values: [a_fields.len + b_fields.len]UEnumSize = undefined;
     var i: usize = 0;
     for (a_fields, a_enum_fields) |field, enum_field| {
-        field_names[i] = field.name;
+        fields[i] = field;
-        field_types[i] = field.type;
-        field_attributes[i] = .{ .@"align" = field.alignment };
         var enum_f = enum_field;
         enum_f.value = i;
-        enum_names[i] = enum_f.name;
+        enum_fields[i] = enum_f;
-        enum_values[i] = enum_f.value;
         i += 1;
     }
     for (b_fields, b_enum_fields) |field, enum_field| {
-        field_names[i] = field.name;
+        fields[i] = field;
-        field_types[i] = field.type;
-        field_attributes[i] = .{ .@"align" = field.alignment };
         var enum_f = enum_field;
         enum_f.value = i;
-        enum_names[i] = enum_f.name;
+        enum_fields[i] = enum_f;
-        enum_values[i] = enum_f.value;
         i += 1;
     }
 
-    // NOTE declarations are not supported for `comptime` types: https://github.com/ziglang/zig/issues/6709
+    const log2_i = @bitSizeOf(@TypeOf(i)) - @clz(i);
-    // -> will lead to a compilation error when constructing the tagged union
+
-    //    at the end of this function in case at least one of the provided tagged
+    const EventType = @Type(.{ .int = .{
-    //    unions to merge contains declarations (which in this case can only be the
+        .signedness = .unsigned,
-    //    user provided one)
+        .bits = log2_i,
-    const a_enum_decls = @typeInfo(A).@"union".decls;
+    } });
-    const b_enum_decls = @typeInfo(B).@"union".decls;
+
-    var decl_names: [a_enum_decls.len + b_enum_decls.len]std.builtin.Type.Declaration = undefined;
+    const Event = @Type(.{ .@"enum" = .{
-    var j: usize = 0;
+        .tag_type = EventType,
-    for (a_enum_decls) |decl| {
+        .fields = enum_fields[0..],
-        decl_names[j] = decl.name;
+        .decls = &.{},
-        j += 1;
+        .is_exhaustive = true,
-    }
+    } });
-    for (b_enum_decls) |decl| {
+
-        decl_names[j] = decl.name;
+    return @Type(.{ .@"union" = .{
-        j += 1;
+        .layout = .auto,
+        .tag_type = Event,
+        .fields = fields[0..],
+        .decls = &.{},
+    } });
 }
 
-    const EventType = @Int(.unsigned, @bitSizeOf(@TypeOf(i)) - @clz(i));
+// Determine at `comptime` whether the provided type `E` is an `union(enum)`.
-
+pub fn isTaggedUnion(comptime E: type) bool {
-    const Event = @Enum(EventType, .exhaustive, enum_names[0..], enum_values[0..]);
+    switch (@typeInfo(E)) {
-
+        .@"union" => |u| {
-    return @Union(.auto, Event, field_names[0..], field_types[0..], field_attributes[0..]);
+            if (u.tag_type) |_| {} else {
-}
-
-/// Determine whether the provided type `T` is a tagged union: `union(enum)`.
-pub fn isTaggedUnion(comptime T: type) bool {
-    switch (@typeInfo(T)) {
-        .@"union" => |u| if (u.tag_type) |_| {} else {
                 return false;
+            }
         },
         else => return false,
     }
     return true;
 }
 
-/// Determine whether the provided type `T` is a `struct`.
-pub fn isStruct(comptime T: type) bool {
-    return switch (@typeInfo(T)) {
-        .@"struct" => true,
-        else => false,
-    };
-}
-
 const std = @import("std");
 const input = @import("input.zig");
 const terminal = @import("terminal.zig");

src/input.zig

@@ -65,30 +65,7 @@ pub const Key = packed struct {
         return meta.eql(this, other);
     }
 
-    /// Determine if the `Key` is an unicode character that can be printed to
+    // TODO might be useful to use the std.ascii stuff!
-    /// the screen. This means that the code point of the `Key` is an ascii
-    /// character between 32 - 255 (with the exception of 127 = Delete) and no
-    /// modifiers (alt and/or ctrl) are used.
-    ///
-    /// # Example
-    ///
-    /// Get user input's from the .key event from the application event loop:
-    ///
-    /// ```zig
-    /// switch (event) {
-    ///   .key => |key| if (key.isUnicode()) try this.input.append(key.cp),
-    ///   else => {},
-    /// }
-    /// ```
-    pub fn isUnicode(this: @This()) bool {
-        return this.mod.alt == false and this.mod.ctrl == false and // no modifier keys
-            (this.cp >= 32 and this.cp <= 126 or // ascii printable characters (except for input.Delete)
-                this.cp >= 128 and this.cp <= 255) or // extended ascii codes
-            ((this.cp >= 0x0080 and this.cp <= 0x07FF) or
-                (this.cp >= 0x0800 and this.cp <= 0xFFFF) or
-                (this.cp >= 0x100000 and this.cp <= 0x10FFFF)) and // allowed unicode character ranges (2 - 4 byte characters)
-                (this.cp < 57348 or this.cp > 57454); // no other predifined meanings (i.e. arrow keys, etc.)
-    }
 
     /// Determine if the `Key` is an ascii character that can be printed to
     /// the screen. This means that the code point of the `Key` is an ascii

src/queue.zig

@@ -1,7 +1,7 @@
 // taken from https://github.com/rockorager/libvaxis/blob/main/src/queue.zig (MIT-License)
 // with slight modifications
 
-/// Queue implementation. Thread safe. Fixed size. _Blocking_ `push` and `pop`. _Polling_ through `tryPop` and `tryPush`.
+/// Queue implementation. Thread safe. Fixed size. Blocking push and pop. Polling through tryPop and tryPush.
 pub fn Queue(comptime T: type, comptime size: usize) type {
     return struct {
         buf: [size]T = undefined,
@@ -215,7 +215,7 @@ fn sleepyPop(q: *Queue(u8, 2)) !void {
     // still full and the push in the other thread is still blocked
     // waiting for space.
     try Thread.yield();
-    std.Thread.sleep(std.time.ns_per_s);
+    std.time.sleep(std.time.ns_per_s);
     // Finally, let that other thread go.
     try testing.expectEqual(1, q.pop());
 
@@ -225,7 +225,7 @@ fn sleepyPop(q: *Queue(u8, 2)) !void {
         try Thread.yield();
     // But we want to ensure that there's a second push waiting, so
     // here's another sleep.
-    std.Thread.sleep(std.time.ns_per_s / 2);
+    std.time.sleep(std.time.ns_per_s / 2);
 
     // Another spurious wake...
     q.not_full.signal();
@@ -233,7 +233,7 @@ fn sleepyPop(q: *Queue(u8, 2)) !void {
     // And another chance for the other thread to see that it's
     // spurious and go back to sleep.
     try Thread.yield();
-    std.Thread.sleep(std.time.ns_per_s / 2);
+    std.time.sleep(std.time.ns_per_s / 2);
 
     // Pop that thing and we're done.
     try testing.expectEqual(2, q.pop());
@@ -270,14 +270,14 @@ test "Fill, block, fill, block" {
 fn sleepyPush(q: *Queue(u8, 1)) !void {
     // Try to ensure the other thread has already started trying to pop.
     try Thread.yield();
-    std.Thread.sleep(std.time.ns_per_s / 2);
+    std.time.sleep(std.time.ns_per_s / 2);
 
     // Spurious wake
     q.not_full.signal();
     q.not_empty.signal();
 
     try Thread.yield();
-    std.Thread.sleep(std.time.ns_per_s / 2);
+    std.time.sleep(std.time.ns_per_s / 2);
 
     // Stick something in the queue so it can be popped.
     q.push(1);
@@ -286,7 +286,7 @@ fn sleepyPush(q: *Queue(u8, 1)) !void {
         try Thread.yield();
     // Give the other thread time to block again.
     try Thread.yield();
-    std.Thread.sleep(std.time.ns_per_s / 2);
+    std.time.sleep(std.time.ns_per_s / 2);
 
     // Spurious wake
     q.not_full.signal();
@@ -317,7 +317,7 @@ test "2 readers" {
     const t1 = try Thread.spawn(cfg, readerThread, .{&queue});
     const t2 = try Thread.spawn(cfg, readerThread, .{&queue});
     try Thread.yield();
-    std.Thread.sleep(std.time.ns_per_s / 2);
+    std.time.sleep(std.time.ns_per_s / 2);
     queue.push(1);
     queue.push(1);
     t1.join();

src/render.zig

@@ -58,10 +58,10 @@ pub const Buffered = struct {
     }
 
     /// Render provided cells at size (anchor and dimension) into the *virtual screen*.
-    pub fn render(this: *@This(), comptime Container: type, container: *Container, comptime Model: type, model: *const Model) !void {
+    pub fn render(this: *@This(), comptime T: type, container: *T) !void {
         const size: Point = container.size;
         const origin: Point = container.origin;
-        const cells: []const Cell = try container.content(model);
+        const cells: []const Cell = try container.content();
 
         if (cells.len == 0) return;
 
@@ -80,7 +80,7 @@ pub const Buffered = struct {
         // free immediately
         container.allocator.free(cells);
 
-        for (container.elements.items) |*element| try this.render(Container, element, Model, model);
+        for (container.elements.items) |*element| try this.render(T, element);
     }
 
     /// Write *virtual screen* to alternate screen (should be called once and last during each render loop iteration in the main loop).
@@ -88,7 +88,7 @@ pub const Buffered = struct {
         try terminal.hideCursor();
         // TODO measure timings of rendered frames?
         var cursor_position: ?Point = null;
-        var writer = terminal.writer();
+        const writer = terminal.writer();
         const s = this.screen;
         const vs = this.virtual_screen;
         for (0..this.size.y) |row| {
@@ -104,14 +104,13 @@ pub const Buffered = struct {
                         .x = @truncate(col),
                         .y = @truncate(row),
                     };
-                    try cvs.style.set_cursor_style(&writer);
                 }
 
                 if (cs.eql(cvs)) continue;
 
                 // render differences found in virtual screen
                 try terminal.setCursorPosition(.{ .y = @truncate(row), .x = @truncate(col) });
-                try cvs.value(&writer);
+                try cvs.value(writer);
                 // update screen to be the virtual screen for the next frame
                 s[idx] = vs[idx];
             }

src/style.zig

@@ -12,8 +12,6 @@ fg: Color = .default,
 bg: Color = .default,
 ul: Color = .default,
 cursor: bool = false,
-cursor_color: Color = .default,
-cursor_shape: CursorShape = .default,
 ul_style: Underline = .off,
 emphasis: []const Emphasis,
 
@@ -38,51 +36,33 @@ pub const Emphasis = enum(u8) {
     strikethrough,
 };
 
-pub const CursorShape = enum(u4) {
-    default = 0,
-    block_blinking = 1,
-    block_steady,
-    underline_blinking,
-    underline_steady,
-    bar_blinking,
-    bar_steady,
-};
-
 pub fn eql(this: Style, other: Style) bool {
-    // TODO should there be a compare for every field?
     return meta.eql(this, other);
 }
 
-pub fn set_cursor_style(this: Style, writer: *std.Io.Writer) !void {
+// TODO might be useful to use the std.ascii stuff!
-    if (!this.cursor) return;
-    switch (this.cursor_color) {
-        .default => try writer.print(ctlseqs.osc12_reset, .{}),
-        else => try writer.print(ctlseqs.osc12_set, .{@tagName(this.cursor_color)}),
-    }
-    try writer.print(ctlseqs.cursor_shape, .{@intFromEnum(this.cursor_shape)});
-}
 
-pub fn value(this: Style, writer: *std.Io.Writer, cp: u21) !void {
+pub fn value(this: Style, writer: anytype, cp: u21) !void {
     var buffer: [4]u8 = undefined;
     const bytes = try unicode.utf8Encode(cp, &buffer);
     assert(bytes > 0);
     // build ansi sequence for 256 colors ...
     // foreground
-    try writer.printAscii("\x1b[", .{});
+    try format(writer, "\x1b[", .{});
     try this.fg.write(writer, .fg);
     // background
-    try writer.printAsciiChar(';', .{});
+    try format(writer, ";", .{});
     try this.bg.write(writer, .bg);
     // underline
     // FIX assert that if the underline property is set that the ul style and the attribute for underlining is available
-    try writer.printAsciiChar(';', .{});
+    try format(writer, ";", .{});
     try this.ul.write(writer, .ul);
     // append styles (aka attributes like bold, italic, strikethrough, etc.)
-    for (this.emphasis) |attribute| try writer.print(";{d}", .{@intFromEnum(attribute)});
+    for (this.emphasis) |attribute| try format(writer, ";{d}", .{@intFromEnum(attribute)});
-    try writer.printAsciiChar('m', .{});
+    try format(writer, "m", .{});
     // content
-    try writer.printAscii(buffer[0..bytes], .{});
+    try format(writer, "{s}", .{buffer[0..bytes]});
-    try writer.printAscii("\x1b[0m", .{});
+    try format(writer, "\x1b[0m", .{});
 }
 
 // TODO implement helper functions for terminal capabilities:
@@ -93,6 +73,6 @@ const std = @import("std");
 const unicode = std.unicode;
 const meta = std.meta;
 const assert = std.debug.assert;
+const format = std.fmt.format;
 const Color = @import("color.zig").Color;
-const ctlseqs = @import("ctlseqs.zig");
 const Style = @This();

src/terminal.zig

@@ -42,11 +42,6 @@ pub fn showCursor() !void {
     _ = try posix.write(posix.STDIN_FILENO, ctlseqs.show_cursor);
 }
 
-pub fn resetCursor() !void {
-    _ = try posix.write(posix.STDIN_FILENO, ctlseqs.reset_cursor_shape);
-    _ = try posix.write(posix.STDIN_FILENO, ctlseqs.osc12_reset);
-}
-
 pub fn setCursorPositionHome() !void {
     _ = try posix.write(posix.STDIN_FILENO, ctlseqs.home);
 }
@@ -59,10 +54,6 @@ pub fn disableMouseSupport() !void {
     _ = try posix.write(posix.STDIN_FILENO, ctlseqs.mouse_reset);
 }
 
-pub fn ringBell() !void {
-    _ = try posix.write(posix.STDIN_FILENO, &.{7});
-}
-
 pub fn read(buf: []u8) !usize {
     return try posix.read(posix.STDIN_FILENO, buf);
 }
@@ -71,25 +62,19 @@ pub fn write(buf: []const u8) !usize {
     return try posix.write(posix.STDIN_FILENO, buf);
 }
 
-fn drainFn(w: *std.Io.Writer, data: []const []const u8, splat: usize) error{WriteFailed}!usize {
+fn contextWrite(context: @This(), data: []const u8) anyerror!usize {
-    _ = w;
+    _ = context;
-    if (data.len == 0 or splat == 0) return 0;
+    return try posix.write(posix.STDOUT_FILENO, data);
-    var len: usize = 0;
-
-    for (data) |bytes| len += posix.write(posix.STDOUT_FILENO, bytes) catch return error.WriteFailed;
-
-    return len;
 }
 
-// TODO I now need to add that much, for just the one function above?
+const Writer = std.io.Writer(
-pub fn writer() std.Io.Writer {
+    @This(),
-    return .{
+    anyerror,
-        .vtable = &.{
+    contextWrite,
-            .drain = drainFn,
+);
-            .flush = std.Io.Writer.noopFlush,
+
-        },
+pub fn writer() Writer {
-        .buffer = &.{},
+    return .{ .context = .{} };
-    };
 }
 
 pub fn setCursorPosition(pos: Point) !void {
@@ -206,7 +191,7 @@ pub fn enableRawMode(bak: *posix.termios) !void {
 }
 
 /// Reverts `enableRawMode` to restore initial functionality.
-pub fn disableRawMode(bak: *const posix.termios) !void {
+pub fn disableRawMode(bak: *posix.termios) !void {
     try posix.tcsetattr(
         posix.STDIN_FILENO,
         .FLUSH,
@@ -247,7 +232,7 @@ const log = std.log.scoped(.terminal);
 const std = @import("std");
 const mem = std.mem;
 const posix = std.posix;
-const assert = std.debug.assert;
+const code_point = @import("code_point");
 const ctlseqs = @import("ctlseqs.zig");
 const input = @import("input.zig");
 const Key = input.Key;

src/testing.zig

@@ -34,10 +34,10 @@ pub const Renderer = struct {
         @memset(this.screen, .{});
     }
 
-    pub fn render(this: *@This(), comptime T: type, container: *const T, comptime Model: type, model: *const Model) !void {
+    pub fn render(this: *@This(), comptime T: type, container: *const T) !void {
         const size: Point = container.size;
         const origin: Point = container.origin;
-        const cells: []const Cell = try container.content(model);
+        const cells: []const Cell = try container.content();
 
         if (cells.len == 0) return;
 
@@ -58,7 +58,7 @@ pub const Renderer = struct {
         // free immediately
         container.allocator.free(cells);
 
-        for (container.elements.items) |*element| try this.render(T, element, Model, model);
+        for (container.elements.items) |*element| try this.render(T, element);
     }
 
     pub fn save(this: @This(), writer: anytype) !void {
@@ -74,8 +74,6 @@ pub const Renderer = struct {
 /// Create a .zon file containing the expected `Cell` slice using the `zterm.testing.Renderer.save` method:
 ///
 /// ```zig
-/// const Model = struct {};
-/// var model: Model = .{};
 /// const file = try std.fs.cwd().createFile("test/container/border/all.zon", .{ .truncate = true });
 /// defer file.close();
 ///
@@ -83,8 +81,8 @@ pub const Renderer = struct {
 /// var renderer: testing.Renderer = .init(allocator, size);
 /// defer renderer.deinit();
 ///
-/// try container.handle(&model, .{ .size = size });
+/// try container.handle(.{ .size = size });
-/// try renderer.render(@TypeOf(container), &container, Model, &.{});
+/// try renderer.render(Container(event.SystemEvent), &container);
 /// try renderer.save(file.writer());
 /// ```
 ///
@@ -93,8 +91,7 @@ pub const Renderer = struct {
 /// Then later load that .zon file at compile time and run your test against this `Cell` slice.
 ///
 /// ```zig
-/// const Model = struct {};
+/// var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
-/// var container: Container(Model, event.SystemEvent) = try .init(std.testing.allocator, .{
 ///     .border = .{
 ///         .color = .green,
 ///         .sides = .all,
@@ -105,57 +102,20 @@ pub const Renderer = struct {
 /// try testing.expectContainerScreen(.{
 ///     .rows = 20,
 ///     .cols = 30,
-/// }, @TypeOf(container), &container, Model, @import("test/container/border.all.zon"));
+/// }, &container, @import("test/container/border.all.zon"));
 /// ```
-pub fn expectContainerScreen(size: Point, comptime T: type, container: *T, comptime Model: type, expected: []const Cell) !void {
+pub fn expectContainerScreen(size: Point, container: *Container(event.SystemEvent), expected: []const Cell) !void {
     const allocator = testing.allocator;
     var renderer: Renderer = .init(allocator, size);
     defer renderer.deinit();
 
-    const model: Model = .{};
+    container.resize(size);
-
+    container.reposition(.{});
-    container.resize(&model, size);
+    try renderer.render(Container(event.SystemEvent), container);
-    container.reposition(&model, .{});
-    try renderer.render(T, container, Model, &model);
 
     try expectEqualCells(.{}, renderer.size, expected, renderer.screen);
 }
 
-/// Taken from: https://codeberg.org/atman/zg/src/branch/master/src/DisplayWidth.zig
-/// Owned by https://codeberg.org/atman licensed under MIT all credits for this function go to him
-fn center(allocator: Allocator, str: []const u8, total_width: usize, pad: []const u8) ![]u8 {
-    if (str.len > total_width) return error.StrTooLong;
-    if (str.len == total_width) return try allocator.dupe(u8, str);
-
-    if (pad.len > total_width or str.len + pad.len > total_width) return error.PadTooLong;
-
-    const margin_width = @divFloor((total_width - str.len), 2);
-    if (pad.len > margin_width) return error.PadTooLong;
-
-    const extra_pad: usize = if (total_width % 2 != str.len % 2) 1 else 0;
-    const pads = @divFloor(margin_width, pad.len) * 2 + extra_pad;
-
-    var result = try allocator.alloc(u8, pads * pad.len + str.len);
-    var bytes_index: usize = 0;
-    var pads_index: usize = 0;
-
-    while (pads_index < pads / 2) : (pads_index += 1) {
-        @memcpy(result[bytes_index..][0..pad.len], pad);
-        bytes_index += pad.len;
-    }
-
-    @memcpy(result[bytes_index..][0..str.len], str);
-    bytes_index += str.len;
-
-    pads_index = 0;
-    while (pads_index < pads / 2 + extra_pad) : (pads_index += 1) {
-        @memcpy(result[bytes_index..][0..pad.len], pad);
-        bytes_index += pad.len;
-    }
-
-    return result;
-}
-
 /// This function is intended to be used only in tests. Test if the two
 /// provided cell arrays are identical. Usually the `Cell` slices are
 /// the contents of a given screen from the `zterm.testing.Renderer`. See
@@ -167,21 +127,28 @@ pub fn expectEqualCells(origin: Point, size: Point, expected: []const Cell, actu
     try testing.expectEqual(expected.len, @as(usize, size.y) * @as(usize, size.x));
 
     var expected_cps = try std.ArrayList(Cell).initCapacity(allocator, size.x);
-    defer expected_cps.deinit(allocator);
+    defer expected_cps.deinit();
 
     var actual_cps = try std.ArrayList(Cell).initCapacity(allocator, size.x);
-    defer actual_cps.deinit(allocator);
+    defer actual_cps.deinit();
 
-    var allocating_writer = std.Io.Writer.Allocating.init(allocator);
+    var output = try std.ArrayList(u8).initCapacity(allocator, expected_cps.capacity * actual_cps.capacity + 5 * size.y);
-    defer allocating_writer.deinit();
+    defer output.deinit();
 
-    var writer = &allocating_writer.writer;
+    var buffer = std.io.bufferedWriter(output.writer());
+    defer buffer.flush() catch {};
+
+    const writer = buffer.writer();
     var differ = false;
 
-    const expected_centered = try center(allocator, "Expected Screen", size.x, " ");
+    const dwd = try DisplayWidth.DisplayWidthData.init(allocator);
+    defer dwd.deinit();
+    const dw: DisplayWidth = .{ .data = &dwd };
+
+    const expected_centered = try dw.center(allocator, "Expected Screen", size.x, " ");
     defer allocator.free(expected_centered);
 
-    const actual_centered = try center(allocator, "Actual Screen", size.x, " ");
+    const actual_centered = try dw.center(allocator, "Actual Screen", size.x, " ");
     defer allocator.free(actual_centered);
 
     try writer.print("Screens are not equivalent.\n{s} ┆ {s}\n", .{ expected_centered, actual_centered });
@@ -197,8 +164,8 @@ pub fn expectEqualCells(origin: Point, size: Point, expected: []const Cell, actu
 
             if (!expected_cell.eql(actual_cell)) differ = true;
 
-            try expected_cps.append(allocator, expected_cell);
+            try expected_cps.append(expected_cell);
-            try actual_cps.append(allocator, actual_cell);
+            try actual_cps.append(actual_cell);
         }
 
         // write screens both formatted to buffer
@@ -211,13 +178,13 @@ pub fn expectEqualCells(origin: Point, size: Point, expected: []const Cell, actu
     if (!differ) return;
 
     // test failed
-    var stdout_buffer: [1024]u8 = undefined;
+    try buffer.flush();
-    const io = debug.lockStderr(&stdout_buffer);
-    defer debug.unlockStderr();
 
-    const error_writer = &io.file_writer.interface;
+    debug.lockStdErr();
-    try error_writer.writeAll(writer.buffer[0..writer.end]);
+    defer debug.unlockStdErr();
-    try error_writer.flush();
+
+    const std_writer = std.io.getStdErr().writer();
+    try std_writer.writeAll(output.items);
     return error.TestExpectEqualCells;
 }
 
@@ -228,4 +195,5 @@ const Allocator = std.mem.Allocator;
 const event = @import("event.zig");
 const Container = @import("container.zig").Container;
 const Cell = @import("cell.zig");
+const DisplayWidth = @import("DisplayWidth");
 const Point = @import("point.zig").Point;