mod: bump zlog dependency

This is a starting point to dynamically loading `markdown` files as blog
entries. With this change the *doc/about.md* and *doc/blog.md* files
are no longer builded into the executable and instead read from the
filesystem during runtime (along with the new test file *doc/test.md*).

build.zig

@@ -4,6 +4,14 @@ pub fn build(b: *std.Build) void {
     const target = b.standardTargetOptions(.{});
     const optimize = b.standardOptimizeOption(.{});
 
+    const zlog = b.dependency("zlog", .{
+        .target = target,
+        .optimize = optimize,
+        .timestamp = false,
+        .stderr = false,
+        .file = "log",
+    });
+
     const zterm = b.dependency("zterm", .{
         .target = target,
         .optimize = optimize,
@@ -17,18 +25,7 @@ pub fn build(b: *std.Build) void {
             .optimize = optimize,
             .imports = &.{
                 .{ .name = "zterm", .module = zterm.module("zterm") },
-                .{
-                    .name = "about",
-                    .module = b.createModule(.{
-                        .root_source_file = b.path("doc/about.md"),
-                    }),
-                },
-                .{
-                    .name = "blog",
-                    .module = b.createModule(.{
-                        .root_source_file = b.path("doc/blog.md"),
-                    }),
-                },
+                .{ .name = "zlog", .module = zlog.module("zlog") },
             },
         }),
     });

build.zig.zon

@@ -6,8 +6,12 @@
     .minimum_zig_version = "0.16.0-dev.463+f624191f9",
     .dependencies = .{
         .zterm = .{
-            .url = "git+https://gitea.yves-biener.de/yves-biener/zterm#89aeac1e968f1390bd945f734aac8612efbab179",
-            .hash = "zterm-0.3.0-1xmmELjzGwBxVlqXRHn7p-sXFU9xPxqFMxF0PY2CkzFn",
+            .url = "git+https://gitea.yves-biener.de/yves-biener/zterm#b3dc8096d76d6e246d48f9034a65997c0047c3c6",
+            .hash = "zterm-0.3.0-1xmmENP4GwBw65udohsoaxc9Kp4Yo7kORt4okY5pLslr",
+        },
+        .zlog = .{
+            .url = "git+https://gitea.yves-biener.de/yves-biener/zlog#f43034cea9a0863e618c3d0a43706ce38c8791cf",
+            .hash = "zlog-0.16.0-6JSlRx1JAADasbK5FS6Qaf0Iq1SCQaH5VZRxT2SRE2xs",
         },
     },
     .paths = .{

doc/blog.md

@@ -1,5 +1,7 @@
-# Blog
-
+---
+title: Welcome to my Blog
+date: 2025-11-01
+---
 This is the main entry page for my blog. I plan on writing on things I feel like worth sharing, mentioning for other developers, tinkers like me.
 
 The blog is currently a work in progress and will be updated once a first version of the tui website supports more dynamic contents.

doc/test.md

@@ -0,0 +1,51 @@
+---
+title: Capabilities of tui-website
+---
+Not everything that can be done with markdown can be representented by this tui-application. It is simple enough to
+support basic markdown files. Currently the text has to be manually reflowed to 120 characters, such that there is no
+issue when rendering (i.e. correct line breaks, etc.)
+
+The following list contains all the available features that are supported (with some examples below):
+
+  - unordered lists (using `-`, `+` and `*`, where the corresponding symbol is used when rendering)
+  * links
+  + blocks
+  - `inline blocks` (written as `inline blocks`)
+  * _italic_ (written as `_italic_`)
+  + **bold** (written as `**bold**`)
+  - headlines (corresponding sub heading six levels deep)
+
+Headings currently require a second newline before the list items to render correctly with a empty line in between the
+following contents and the last list item.
+
+Another paragraph.
+
+# Examples
+
+> quotes are not supported (yet)
+
+The following is a block. Which renders as follows (containing line numbers and **no code highlighting**):
+
+---
+
+```zig
+fn myFunction() void {
+    if (hasFeature()) {
+        // Feature-specific code
+    } else {
+        // Default code
+    }
+}
+
+inline fn hasFeature() bool {
+    return (comptime comptimeCheck()) and runtimeCheck();
+}
+```
+
+## Combinations are possible
+
+1. see this excellent blog post: [Conditionally Disabling Code with comptime in Zig - Mitchell Hashimoto](https://mitchellh.com/writing/zig-comptime-conditional-disable)
+
+### See deeper levels are possible and will be rendered correctly
+
+This is just some placeholder text.

src/content.zig

@@ -1,25 +1,68 @@
 pub fn Content(App: type) type {
     return struct {
+        allocator: Allocator,
+        document: *const App.Model.Document,
+
         pub fn init(allocator: Allocator) @This() {
-            _ = allocator;
-            return .{};
+            return .{
+                .allocator = allocator,
+                .document = undefined,
+            };
         }
 
         pub fn element(this: *@This()) App.Element {
             return .{
                 .ptr = this,
                 .vtable = &.{
+                    .minSize = minSize,
                     .handle = handle,
                     .content = content,
                 },
             };
         }
 
+        fn minSize(ctx: *anyopaque, size: zterm.Point) zterm.Point {
+            const this: *const @This() = @ptrCast(@alignCast(ctx));
+            const text = this.document.content;
+            var index: usize = 0;
+            var new_size: zterm.Point = .{ .x = size.x };
+
+            for (0..text.len) |_| rows: {
+                for (0..size.x) |_| {
+                    if (index == text.len) break :rows;
+                    const cp = text[index];
+                    index += 1;
+
+                    switch (cp) {
+                        '\n' => break,
+                        else => {},
+                    }
+                }
+                new_size.y += 1;
+            }
+            return new_size;
+        }
+
         fn handle(ctx: *anyopaque, model: *App.Model, event: App.Event) !void {
-            _ = ctx;
+            const this: *@This() = @ptrCast(@alignCast(ctx));
             switch (event) {
-                .about => model.page = .about,
-                .blog => model.page = .blog,
+                .init => this.document = &model.document,
+                .about => {
+                    model.page.deinit(this.allocator);
+                    model.page = .about;
+
+                    model.document.deinit(this.allocator);
+                    model.document = .init(try std.fs.cwd().readFileAlloc("./doc/about.md", this.allocator, .unlimited));
+                    this.document = &model.document;
+                },
+                .blog => |path| {
+                    model.page.deinit(this.allocator);
+                    model.page = .{ .blog = path };
+
+                    model.document.deinit(this.allocator);
+                    model.document = .init(try std.fs.cwd().readFileAlloc(if (path) |p| p else "./doc/blog.md", this.allocator, .unlimited));
+                    this.document = &model.document;
+                },
                 else => {},
             }
         }
@@ -28,16 +71,12 @@ pub fn Content(App: type) type {
             _ = ctx;
             assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
-            const text = switch (model.page) {
-                .about => @embedFile("about"),
-                .blog => @embedFile("blog"),
-            };
+            const text = model.document.content;
             var index: usize = 0;
 
             for (0..size.y) |row| {
                 for (0..size.x) |col| {
                     const cell = row * size.x + col;
-                    assert(cell < cells.len);
 
                     if (index == text.len) return;
                     const cp = text[index];
@@ -55,14 +94,6 @@ pub fn Content(App: type) type {
 
 pub fn Title(App: type) type {
     return struct {
-        text: []const u8,
-
-        pub fn init() @This() {
-            return .{
-                .text = "<Title>",
-            };
-        }
-
         pub fn element(this: *@This()) App.Element {
             return .{
                 .ptr = this,
@@ -72,16 +103,20 @@ pub fn Title(App: type) type {
             };
         }
 
-        fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+        fn content(ctx: *anyopaque, model: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
             const this: *const @This() = @ptrCast(@alignCast(ctx));
+            _ = this;
             assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
-            for (0.., this.text) |idx, cp| {
-                cells[idx].style.fg = .green;
-                cells[idx].style.emphasis = &.{.bold};
-                cells[idx].cp = cp;
 
-                // NOTE do not write over the contents of this `Container`'s `Size`
-                if (idx == cells.len - 1) break;
+            if (model.document.title) |text| {
+                for (0.., text) |idx, cp| {
+                    cells[idx].style.fg = .green;
+                    cells[idx].style.emphasis = &.{.bold};
+                    cells[idx].cp = cp;
+
+                    // NOTE do not write over the contents of this `Container`'s `Size`
+                    if (idx == cells.len - 1) break;
+                }
             }
         }
     };
@@ -89,15 +124,8 @@ pub fn Title(App: type) type {
 
 pub fn InfoBanner(App: type) type {
     return struct {
-        left_text: []const u8,
-        right_text: []const u8,
-
-        pub fn init() @This() {
-            return .{
-                .left_text = "Build with zig",
-                .right_text = "Yves Biener (@yves-biener)",
-            };
-        }
+        left_text: []const u8 = "Build with zig",
+        right_text: []const u8 = "Yves Biener (@yves-biener)",
 
         pub fn element(this: *@This()) App.Element {
             return .{
@@ -108,7 +136,7 @@ pub fn InfoBanner(App: type) type {
             };
         }
 
-        fn content(ctx: *anyopaque, _: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
+        fn content(ctx: *anyopaque, model: *const App.Model, cells: []zterm.Cell, size: zterm.Point) !void {
             const this: *const @This() = @ptrCast(@alignCast(ctx));
             assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
@@ -121,6 +149,22 @@ pub fn InfoBanner(App: type) type {
                 cells[idx].cp = cp;
             }
 
+            switch (model.page) {
+                .about => {},
+                .blog => |path| if (path) |p| page: {
+                    const start_idx = (size.x -| p.len) / 2;
+                    if (start_idx <= this.left_text.len) break :page;
+
+                    for (start_idx.., p) |idx, cp| {
+                        // NOTE do not write over the contents of this `Container`'s `Size`
+                        if (idx == cells.len) break;
+
+                        cells[idx].style.fg = .default;
+                        cells[idx].cp = cp;
+                    }
+                },
+            }
+
             var start_idx = size.x -| this.right_text.len;
             if (start_idx <= this.left_text.len) start_idx = this.left_text.len + 1;
 

src/main.zig

@@ -6,7 +6,12 @@ pub fn main() !void {
 
     const allocator = gpa.allocator();
 
-    var app: App = .init(.{});
+    var app: App = .init(.{
+        .page = .about,
+        .document = .init(try std.fs.cwd().readFileAlloc("./doc/about.md", allocator, .unlimited)),
+    });
+    defer app.model.deinit(allocator);
+
     var renderer = zterm.Renderer.Buffered.init(allocator);
     defer renderer.deinit();
 
@@ -18,6 +23,8 @@ pub fn main() !void {
         },
     }, .{});
     defer container.deinit();
+    var content_container: App.Container = undefined;
+    defer content_container.deinit();
 
     // header with navigation buttons and content's title
     {
@@ -32,7 +39,7 @@ pub fn main() !void {
         }, .{});
         // title
         {
-            var title: Title = .init();
+            var title: Title = .{};
             try header.append(try .init(allocator, .{}, title.element()));
         }
         // about navigation button
@@ -59,17 +66,20 @@ pub fn main() !void {
     }
     // main actual tui_website page content
     {
-        // intermediate container for *padding*
         var content: Content = .init(allocator);
-        var content_container: App.Container = try .init(allocator, .{
+        content_container = try .init(allocator, .{}, content.element());
+
+        var scrollable: App.Scrollable = .init(content_container, .enabled(.green));
+        // intermediate container for *padding* containing the scrollable `Content`
+        var scrollable_container: App.Container = try .init(allocator, .{
             .layout = .{ .padding = .horizontal(2) },
         }, .{});
-        try content_container.append(try .init(allocator, .{}, content.element()));
-        try container.append(content_container);
+        try scrollable_container.append(try .init(allocator, .{}, scrollable.element()));
+        try container.append(scrollable_container);
     }
     // footer
     {
-        var info_banner: InfoBanner = .init();
+        var info_banner: InfoBanner = .{};
         const footer: App.Container = try .init(allocator, .{
             .size = .{
                 .dim = .{ .y = 1 },
@@ -91,6 +101,8 @@ pub fn main() !void {
         switch (event) {
             .key => |key| {
                 if (key.eql(.{ .cp = 'c', .mod = .{ .ctrl = true } })) app.quit();
+                // test if the event handling is working correctly
+                if (key.eql(.{ .cp = zterm.input.Space })) app.postEvent(.{ .blog = allocator.dupe(u8, "./doc/test.md") catch unreachable });
             },
             .err => |err| log.err("Received {s} with message: {s}", .{ @errorName(err.err), err.msg }),
             else => {},
@@ -118,17 +130,16 @@ pub fn main() !void {
 }
 
 pub const panic = App.panic_handler;
+pub const std_options = zlog.std_options;
 const log = std.log.scoped(.default);
 
 const std = @import("std");
 const assert = std.debug.assert;
+const zlog = @import("zlog");
 const zterm = @import("zterm");
 const App = zterm.App(
     Model,
-    union(enum) {
-        about,
-        blog,
-    },
+    Model.Pages,
 );
 
 const contents = @import("content.zig");

src/model.zig

@@ -1,6 +1,71 @@
-page: Pages = .blog,
+page: Pages,
+document: Document,
 
-const Pages = enum {
+pub fn deinit(this: *@This(), allocator: Allocator) void {
+    this.page.deinit(allocator);
+    this.document.deinit(allocator);
+
+    this.page = undefined;
+    this.document = undefined;
+}
+
+pub const Pages = union(enum) {
     about,
-    blog,
+    blog: ?[]const u8,
+
+    pub fn deinit(this: @This(), allocator: Allocator) void {
+        switch (this) {
+            .blog => |path| if (path) |p| allocator.free(p),
+            else => {},
+        }
+    }
 };
+
+pub const Document = struct {
+    // preemble:
+    title: ?[]const u8 = null,
+    date: ?[]const u8 = null,
+    content: []const u8 = undefined,
+    ptr: []const u8,
+
+    const Preemble = enum {
+        title,
+        date,
+    };
+
+    pub fn init(content: []const u8) @This() {
+        if (std.mem.startsWith(u8, content, "---\n")) {
+            var document: @This() = .{ .ptr = content };
+            // we assume the content includes a preemble
+            var iter = std.mem.splitSequence(u8, content, "---\n");
+            assert(iter.next().?.len == 0);
+            if (iter.next()) |preemble| {
+                var lines = std.mem.splitScalar(u8, preemble, '\n');
+                while (lines.next()) |line| {
+                    var entry = std.mem.splitSequence(u8, line, ": ");
+                    const key = entry.next().?;
+                    const value = entry.next();
+                    assert(entry.next() == null);
+                    if (std.meta.stringToEnum(Preemble, key)) |k| switch (k) {
+                        .title => document.title = value,
+                        .date => document.date = value,
+                    };
+                }
+            }
+            document.content = iter.rest();
+            return document;
+        } else return .{
+            .content = content,
+            .ptr = content,
+        };
+    }
+
+    pub fn deinit(this: *@This(), allocator: Allocator) void {
+        allocator.free(this.ptr);
+        this.* = .{ .ptr = undefined };
+    }
+};
+
+const std = @import("std");
+const assert = std.debug.assert;
+const Allocator = std.mem.Allocator;

src/navigation.zig

@@ -33,7 +33,11 @@ pub fn NavigationButton(App: type) fn (std.meta.FieldEnum(App.Event)) type {
                     switch (event) {
                         .about, .blog => this.highlight = event == page,
                         // TODO accept key input too?
-                        .mouse => |mouse| if (mouse.button == .left and mouse.kind == .release) this.queue.push(page),
+                        .mouse => |mouse| if (mouse.button == .left and mouse.kind == .release) this.queue.push(switch (page) {
+                            .about => .about,
+                            .blog => .{ .blog = null },
+                            else => @compileError("The provided navigation button event to trigger is not a `App.Model.Pages` enum variation."),
+                        }),
                         else => {},
                     }
                 }