add TextElement for "New Meld" button

src/main.zig

@@ -323,6 +323,7 @@ pub fn main() !void {
                 .{
                     .hovered = if (hovered_action) |ha| ha.command else null,
                     .deck = deck_sprites,
+                    .font = canvas.font,
                 },
                 .{ 0, 0 },
                 .{
@@ -344,6 +345,7 @@ pub fn main() !void {
                 .{
                     .hovered = if (hovered_action) |ha| ha.command else null,
                     .deck = deck_sprites,
+                    .font = canvas.font,
                 },
                 .{ 0, 0 },
                 .{
@@ -382,6 +384,7 @@ const Action = struct {
 const RenderResources = struct {
     hovered: ?[]const u8,
     deck: DeckSprites,
+    font: seizer.Canvas.Font,
 };
 
 pub const Element = struct {
@@ -835,6 +838,71 @@ pub const CardElement = struct {
     }
 };
 
+pub const TextElement = struct {
+    allocator: std.mem.Allocator,
+    text: []const u8,
+    command: ?[]const u8,
+
+    pub fn create(allocator: std.mem.Allocator, options: struct { text: []const u8, command: ?[]const u8 }) !*@This() {
+        const this = try allocator.create(@This());
+        errdefer allocator.destroy(this);
+
+        this.* = .{
+            .allocator = allocator,
+            .text = options.text,
+            .command = options.command,
+        };
+        return this;
+    }
+
+    pub fn element(this: *@This()) Element {
+        return Element{
+            .pointer = this,
+            .interface = &Element.Interface{
+                .minimum_size = &element_minimum_size,
+                .render = &element_render,
+                .get_actions = &element_get_actions,
+            },
+        };
+    }
+
+    pub fn element_minimum_size(pointer: ?*anyopaque, render_resources: RenderResources) [2]f32 {
+        const this: *@This() = @ptrCast(@alignCast(pointer));
+        return render_resources.font.textSize(this.text, 1);
+    }
+
+    pub fn element_render(pointer: ?*anyopaque, canvas: *seizer.Canvas, render_resources: RenderResources, min: [2]f32, max: [2]f32) void {
+        const this: *@This() = @ptrCast(@alignCast(pointer));
+        _ = max;
+
+        const text_size = canvas.writeText(min, this.text, .{});
+
+        if (render_resources.hovered != null and this.command != null and std.mem.eql(u8, render_resources.hovered.?, this.command.?)) {
+            canvas.rect(
+                .{ min[0], min[1] },
+                text_size,
+                .{ .color = .{ 0xAA, 0xFF, 0xAA, 0x60 } },
+            );
+        }
+    }
+
+    pub fn element_get_actions(pointer: ?*anyopaque, actions: *std.ArrayList(Action), render_resources: RenderResources, min: [2]f32, max: [2]f32) Element.Error!void {
+        const this: *@This() = @ptrCast(@alignCast(pointer));
+
+        _ = render_resources;
+
+        if (this.command) |command| {
+            try actions.append(.{
+                .center = [2]f32{
+                    (min[0] + max[0]) / 2,
+                    (min[1] + max[1]) / 2,
+                },
+                .command = command,
+            });
+        }
+    }
+};
+
 /// Handler at the start of a turn, while the player is drawing a card.
 fn drawCardHandler(arena: std.mem.Allocator, request: Request) HandlerError!Response {
     if (request.command) |command| {
@@ -912,6 +980,14 @@ fn playerTurnHandler(arena: std.mem.Allocator, request: Request) HandlerError!Re
         }
     }
 
+    var new_meld_text = try TextElement.create(arena, .{
+        .text = "New Meld",
+        .command = "new-meld",
+    });
+
+    var melds_hbox = try HBox.create(arena);
+    try melds_hbox.addElement(new_meld_text.element());
+
     var draw_pile = try Pile.create(arena, request.game_state.draw_pile.items);
     draw_pile.hidden = true;
 
@@ -934,6 +1010,7 @@ fn playerTurnHandler(arena: std.mem.Allocator, request: Request) HandlerError!Re
     var page = try Page.create(arena);
     try page.addElement(.{ 0.5, 0.5 }, .{ 0.5, 0.5 }, draw_discard_hbox.element());
     try page.addElement(.{ 0.5, 1 }, .{ 0.5, 1 }, hand.element());
+    try page.addElement(.{ 0.5, 0 }, .{ 0.5, 0 }, melds_hbox.element());
 
     return Response{ .page = page.element() };
 }