feat(element): parameter *const App.Model

The renderer will provide `resize`, `reposition` and `minSize` (for
the `Scrollable` `Element`) with a read-only pointer to the model of
the application (similar to how it is already done for `handle` and
`content`). Every interface function now has the same data that it can
each use for implementing its corresponding task based on local and
shared variables through the element instance and model pointer.

examples/continuous.zig

@@ -231,8 +231,8 @@ pub fn main() !void {
             }
         }
 
-        container.resize(try renderer.resize());
-        container.reposition(.{});
+        container.resize(&app.model, try renderer.resize());
+        container.reposition(&app.model, .{});
         try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
         try renderer.flush();
     }

examples/demo.zig

@@ -182,8 +182,8 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(try renderer.resize());
-        container.reposition(.{});
+        container.resize(&app.model, try renderer.resize());
+        container.reposition(&app.model, .{});
         try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
         try renderer.flush();
     }

examples/elements/alignment.zig

@@ -86,8 +86,8 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(try renderer.resize());
-        container.reposition(.{});
+        container.resize(&app.model, try renderer.resize());
+        container.reposition(&app.model, .{});
         try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
         try renderer.flush();
     }

examples/elements/button.zig

@@ -135,8 +135,8 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(try renderer.resize());
-        container.reposition(.{});
+        container.resize(&app.model, try renderer.resize());
+        container.reposition(&app.model, .{});
         try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
         try renderer.flush();
     }

examples/elements/input.zig

@@ -149,8 +149,8 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(try renderer.resize());
-        container.reposition(.{});
+        container.resize(&app.model, try renderer.resize());
+        container.reposition(&app.model, .{});
         try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
         try renderer.flush();
     }

examples/elements/progress.zig

@@ -155,8 +155,8 @@ pub fn main() !void {
             }
         }
 
-        container.resize(try renderer.resize());
-        container.reposition(.{});
+        container.resize(&app.model, try renderer.resize());
+        container.reposition(&app.model, .{});
         try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
         try renderer.flush();
     }

examples/elements/radio-button.zig

@@ -83,8 +83,8 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(try renderer.resize());
-        container.reposition(.{});
+        container.resize(&app.model, try renderer.resize());
+        container.reposition(&app.model, .{});
         try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
         try renderer.flush();
     }

examples/elements/scrollable.zig

@@ -184,8 +184,8 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(try renderer.resize());
-        container.reposition(.{});
+        container.resize(&app.model, try renderer.resize());
+        container.reposition(&app.model, .{});
         try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
         try renderer.flush();
     }

examples/elements/selection.zig

@@ -83,8 +83,8 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(try renderer.resize());
-        container.reposition(.{});
+        container.resize(&app.model, try renderer.resize());
+        container.reposition(&app.model, .{});
         try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
         try renderer.flush();
     }

examples/errors.zig

@@ -146,8 +146,8 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(try renderer.resize());
-        container.reposition(.{});
+        container.resize(&app.model, try renderer.resize());
+        container.reposition(&app.model, .{});
         try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
         try renderer.flush();
     }

examples/layouts/grid.zig

@@ -102,8 +102,8 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(try renderer.resize());
-        container.reposition(.{});
+        container.resize(&app.model, try renderer.resize());
+        container.reposition(&app.model, .{});
         try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
         try renderer.flush();
     }

examples/layouts/horizontal.zig

@@ -94,8 +94,8 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(try renderer.resize());
-        container.reposition(.{});
+        container.resize(&app.model, try renderer.resize());
+        container.reposition(&app.model, .{});
         try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
         try renderer.flush();
     }

examples/layouts/mixed.zig

@@ -110,8 +110,8 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(try renderer.resize());
-        container.reposition(.{});
+        container.resize(&app.model, try renderer.resize());
+        container.reposition(&app.model, .{});
         try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
         try renderer.flush();
     }

examples/layouts/vertical.zig

@@ -93,8 +93,8 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(try renderer.resize());
-        container.reposition(.{});
+        container.resize(&app.model, try renderer.resize());
+        container.reposition(&app.model, .{});
         try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
         try renderer.flush();
     }

examples/styles/palette.zig

@@ -89,8 +89,8 @@ pub fn main() !void {
             else => {},
         }
 
-        container.resize(try renderer.resize());
-        container.reposition(.{});
+        container.resize(&app.model, try renderer.resize());
+        container.reposition(&app.model, .{});
         try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
         try renderer.flush();
     }

examples/styles/text.zig

@@ -117,7 +117,7 @@ const TextStyles = struct {
         };
     }
 
-    fn minSize(ctx: *anyopaque, size: zterm.Point) zterm.Point {
+    fn minSize(ctx: *anyopaque, _: *const App.Model, size: zterm.Point) zterm.Point {
         _ = ctx;
         _ = size;
         return .{
@@ -253,8 +253,8 @@ pub fn main() !void {
             }
         }
 
-        container.resize(try renderer.resize());
-        container.reposition(.{});
+        container.resize(&app.model, try renderer.resize());
+        container.reposition(&app.model, .{});
         try renderer.render(@TypeOf(container), &container, App.Model, &app.model);
         try renderer.flush();
     }

src/container.zig

@@ -654,10 +654,10 @@ pub fn Container(Model: type, Event: type) type {
             try this.elements.append(this.allocator, element);
         }
 
-        pub fn reposition(this: *@This(), origin: Point) void {
+        pub fn reposition(this: *@This(), model: *const Model, origin: Point) void {
             const layout = this.properties.layout;
             this.origin = origin;
-            this.element.reposition(origin);
+            this.element.reposition(model, origin);
 
             var offset = origin.add(.{
                 .x = Layout.getAbsolutePadding(layout.padding.left, this.size.x),
@@ -669,7 +669,7 @@ pub fn Container(Model: type, Event: type) type {
             if (sides.top) offset.y += 1;
 
             for (this.elements.items) |*child| {
-                child.reposition(offset);
+                child.reposition(model, offset);
 
                 switch (layout.direction) {
                     .horizontal => offset.x += child.size.x + layout.gap,
@@ -739,7 +739,7 @@ pub fn Container(Model: type, Event: type) type {
         }
 
         /// 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(), max_size: Point) void {
+        fn grow_resize(this: *@This(), model: *const Model, 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)),
@@ -881,11 +881,11 @@ pub fn Container(Model: type, Event: type) type {
                 }
             }
 
-            this.element.resize(this.size);
-            for (this.elements.items) |*child| child.grow_resize(child.size);
+            this.element.resize(model, this.size);
+            for (this.elements.items) |*child| child.grow_resize(model, child.size);
         }
 
-        pub fn resize(this: *@This(), size: Point) void {
+        pub fn resize(this: *@This(), model: *const Model, size: Point) void {
             // NOTE assume that this function is only called for the root `Container`
             this.size = size;
             const fit_size = this.fit_resize();
@@ -902,7 +902,7 @@ pub fn Container(Model: type, Event: type) type {
                     .y = @max(size.y, fit_size.y),
                 },
             }
-            this.grow_resize(this.size);
+            this.grow_resize(model, this.size);
         }
 
         pub fn handle(this: *const @This(), model: *Model, event: Event) !void {

src/element.zig

@@ -15,9 +15,9 @@ pub fn Element(Model: type, Event: type) type {
         vtable: *const VTable = &.{},
 
         pub const VTable = struct {
-            minSize: ?*const fn (ctx: *anyopaque, size: Point) Point = null,
-            resize: ?*const fn (ctx: *anyopaque, size: Point) void = null,
-            reposition: ?*const fn (ctx: *anyopaque, origin: Point) void = null,
+            minSize: ?*const fn (ctx: *anyopaque, model: *const Model, size: Point) Point = null,
+            resize: ?*const fn (ctx: *anyopaque, model: *const Model, size: Point) void = null,
+            reposition: ?*const fn (ctx: *anyopaque, model: *const Model, origin: Point) void = null,
             handle: ?*const fn (ctx: *anyopaque, model: *Model, event: Event) anyerror!void = null,
             content: ?*const fn (ctx: *anyopaque, model: *const Model, cells: []Cell, size: Point) anyerror!void = null,
         };
@@ -35,9 +35,9 @@ pub fn Element(Model: type, Event: type) type {
         /// Currently only used for `Scrollable` elements, such that the
         /// directly nested element in the `Scrollable`'s `Container` can
         /// request a minimal size for its contents.
-        pub inline fn minSize(this: @This(), size: Point) Point {
+        pub inline fn minSize(this: @This(), model: *const Model, size: Point) Point {
             if (this.vtable.minSize) |minSize_fn| {
-                const min_size = minSize_fn(this.ptr, size);
+                const min_size = minSize_fn(this.ptr, model, size);
                 return .{
                     .x = @max(size.x, min_size.x),
                     .y = @max(size.y, min_size.y),
@@ -46,15 +46,15 @@ pub fn Element(Model: type, Event: type) type {
         }
 
         /// Resize the corresponding `Element` with the given *size*.
-        pub inline fn resize(this: @This(), size: Point) void {
+        pub inline fn resize(this: @This(), model: *const Model, size: Point) void {
             if (this.vtable.resize) |resize_fn|
-                resize_fn(this.ptr, size);
+                resize_fn(this.ptr, model, size);
         }
 
         /// Reposition the corresponding `Element` with the given *origin*.
-        pub inline fn reposition(this: @This(), origin: Point) void {
+        pub inline fn reposition(this: @This(), model: *const Model, origin: Point) void {
             if (this.vtable.reposition) |reposition_fn|
-                reposition_fn(this.ptr, origin);
+                reposition_fn(this.ptr, model, origin);
         }
 
         /// Handle the received event. The event is one of the user provided
@@ -161,13 +161,13 @@ pub fn Alignment(Model: type, Event: type) type {
             };
         }
 
-        fn resize(ctx: *anyopaque, size: Point) void {
+        fn resize(ctx: *anyopaque, model: *const Model, size: Point) void {
             const this: *@This() = @ptrCast(@alignCast(ctx));
             this.size = size;
-            this.container.resize(size);
+            this.container.resize(model, size);
         }
 
-        fn reposition(ctx: *anyopaque, anchor: Point) void {
+        fn reposition(ctx: *anyopaque, model: *const Model, anchor: Point) void {
             const this: *@This() = @ptrCast(@alignCast(ctx));
             var origin = anchor;
             origin.x = switch (this.configuration.h) {
@@ -180,7 +180,7 @@ pub fn Alignment(Model: type, Event: type) type {
                 .center => origin.y + (this.size.y / 2) -| (this.container.size.y / 2),
                 .end => this.size.y -| this.container.size.y,
             };
-            this.container.reposition(origin);
+            this.container.reposition(model, origin);
         }
 
         fn handle(ctx: *anyopaque, model: *Model, event: Event) !void {
@@ -270,13 +270,13 @@ pub fn Scrollable(Model: type, Event: type) type {
             };
         }
 
-        fn resize(ctx: *anyopaque, size: Point) void {
+        fn resize(ctx: *anyopaque, model: *const Model, size: Point) void {
             const this: *@This() = @ptrCast(@alignCast(ctx));
             const last_max_anchor_x = this.container_size.x -| this.size.x;
             const last_max_anchor_y = this.container_size.y -| this.size.y;
 
             // NOTE `container_size` denotes the `size` required for the container contents
-            var container_size = this.container.element.minSize(size);
+            var container_size = this.container.element.minSize(model, size);
             if (this.configuration.scrollbar) {
                 this.configuration.y_axis = this.container.properties.size.dim.x > size.x or container_size.x > size.x;
                 this.configuration.x_axis = this.container.properties.size.dim.y > size.y or container_size.y > size.y;
@@ -287,7 +287,7 @@ pub fn Scrollable(Model: type, Event: type) type {
             // NOTE this call is at this point required as the container size
             // may also be defined through the `Container`'s `Properties`, which
             // may define a dimension (for static layouts)
-            this.container.resize(container_size); // notify the container about the minimal size it should have
+            this.container.resize(model, container_size); // notify the container about the minimal size it should have
             // update the calculated size of the container
             container_size = this.container.size;
 
@@ -302,9 +302,9 @@ pub fn Scrollable(Model: type, Event: type) type {
             this.container_size = container_size;
         }
 
-        fn reposition(ctx: *anyopaque, _: Point) void {
+        fn reposition(ctx: *anyopaque, model: *const Model, _: Point) void {
             const this: *@This() = @ptrCast(@alignCast(ctx));
-            this.container.reposition(.{});
+            this.container.reposition(model, .{});
         }
 
         fn handle(ctx: *anyopaque, model: *Model, event: Event) !void {
@@ -1140,8 +1140,8 @@ test "scrollable vertical" {
     var renderer: testing.Renderer = .init(allocator, size);
     defer renderer.deinit();
 
-    container.resize(size);
-    container.reposition(.{});
+    container.resize(&.{}, size);
+    container.reposition(&.{}, .{});
     try renderer.render(@TypeOf(container), &container, Model, &.{});
     try testing.expectEqualCells(.{}, renderer.size, @import("test/element/scrollable.vertical.top.zon"), renderer.screen);
 
@@ -1257,8 +1257,8 @@ test "scrollable vertical with scrollbar" {
     var renderer: testing.Renderer = .init(allocator, size);
     defer renderer.deinit();
 
-    container.resize(size);
-    container.reposition(.{});
+    container.resize(&.{}, size);
+    container.reposition(&.{}, .{});
     try renderer.render(@TypeOf(container), &container, Model, &.{});
     try testing.expectEqualCells(.{}, renderer.size, @import("test/element/scrollable.vertical.scrollbar.top.zon"), renderer.screen);
 
@@ -1337,8 +1337,8 @@ test "scrollable horizontal" {
     var renderer: testing.Renderer = .init(allocator, size);
     defer renderer.deinit();
 
-    container.resize(size);
-    container.reposition(.{});
+    container.resize(&.{}, size);
+    container.reposition(&.{}, .{});
     try renderer.render(@TypeOf(container), &container, Model, &.{});
     try testing.expectEqualCells(.{}, renderer.size, @import("test/element/scrollable.horizontal.left.zon"), renderer.screen);
 
@@ -1417,8 +1417,8 @@ test "scrollable horizontal with scrollbar" {
     var renderer: testing.Renderer = .init(allocator, size);
     defer renderer.deinit();
 
-    container.resize(size);
-    container.reposition(.{});
+    container.resize(&.{}, size);
+    container.reposition(&.{}, .{});
     try renderer.render(@TypeOf(container), &container, Model, &.{});
     try testing.expectEqualCells(.{}, renderer.size, @import("test/element/scrollable.horizontal.scrollbar.left.zon"), renderer.screen);
 
@@ -1631,8 +1631,8 @@ test "input element" {
     var renderer: testing.Renderer = .init(allocator, size);
     defer renderer.deinit();
 
-    container.resize(size);
-    container.reposition(.{});
+    container.resize(&.{}, size);
+    container.reposition(&.{}, .{});
     try renderer.render(@TypeOf(container), &container, Model, &.{});
     // try testing.expectEqualCells(.{}, renderer.size, @import("test/element/input.without.text.zon"), renderer.screen);
 
@@ -1697,8 +1697,8 @@ test "button" {
     var renderer: testing.Renderer = .init(allocator, size);
     defer renderer.deinit();
 
-    container.resize(size);
-    container.reposition(.{});
+    container.resize(&.{}, size);
+    container.reposition(&.{}, .{});
     try renderer.render(@TypeOf(container), &container, Model, &.{});
     // try testing.expectEqualCells(.{}, renderer.size, @import("test/element/button.zon"), renderer.screen);
 
@@ -1755,8 +1755,8 @@ test "progress" {
     var renderer: testing.Renderer = .init(allocator, size);
     defer renderer.deinit();
 
-    container.resize(size);
-    container.reposition(.{});
+    container.resize(&.{}, size);
+    container.reposition(&.{}, .{});
     try renderer.render(@TypeOf(container), &container, Model, &.{});
     // try testing.expectEqualCells(.{}, renderer.size, @import("test/element/progress_zero.zon"), renderer.screen);
 
@@ -1764,8 +1764,8 @@ test "progress" {
     try container.handle(&model, .{
         .progress = 25,
     });
-    container.resize(size);
-    container.reposition(.{});
+    container.resize(&.{}, size);
+    container.reposition(&.{}, .{});
     try renderer.render(@TypeOf(container), &container, Model, &.{});
     // try testing.expectEqualCells(.{}, renderer.size, @import("test/element/progress_one_quarter.zon"), renderer.screen);
 
@@ -1773,8 +1773,8 @@ test "progress" {
     try container.handle(&model, .{
         .progress = 50,
     });
-    container.resize(size);
-    container.reposition(.{});
+    container.resize(&.{}, size);
+    container.reposition(&.{}, .{});
     try renderer.render(@TypeOf(container), &container, Model, &.{});
     // try testing.expectEqualCells(.{}, renderer.size, @import("test/element/progress_half.zon"), renderer.screen);
 
@@ -1782,8 +1782,8 @@ test "progress" {
     try container.handle(&model, .{
         .progress = 75,
     });
-    container.resize(size);
-    container.reposition(.{});
+    container.resize(&.{}, size);
+    container.reposition(&.{}, .{});
     try renderer.render(@TypeOf(container), &container, Model, &.{});
     // try testing.expectEqualCells(.{}, renderer.size, @import("test/element/progress_three_quarter.zon"), renderer.screen);
 
@@ -1791,8 +1791,8 @@ test "progress" {
     try container.handle(&model, .{
         .progress = 100,
     });
-    container.resize(size);
-    container.reposition(.{});
+    container.resize(&.{}, size);
+    container.reposition(&.{}, .{});
     try renderer.render(@TypeOf(container), &container, Model, &.{});
     // try testing.expectEqualCells(.{}, renderer.size, @import("test/element/progress_one_hundred.zon"), renderer.screen);
 }

src/testing.zig

@@ -112,9 +112,11 @@ pub fn expectContainerScreen(size: Point, comptime T: type, container: *T, compt
     var renderer: Renderer = .init(allocator, size);
     defer renderer.deinit();
 
-    container.resize(size);
-    container.reposition(.{});
-    try renderer.render(T, container, Model, &.{});
+    const model: Model = .{};
+
+    container.resize(&model, size);
+    container.reposition(&model, .{});
+    try renderer.render(T, container, Model, &model);
 
     try expectEqualCells(.{}, renderer.size, expected, renderer.screen);
 }