//! Label Widget - Static text display
//!
//! A simple widget for displaying text. Supports alignment and styling.

const std = @import("std");
const Context = @import("../core/context.zig").Context;
const Command = @import("../core/command.zig");
const Layout = @import("../core/layout.zig");
const Style = @import("../core/style.zig");

/// Text alignment
pub const Alignment = enum {
    left,
    center,
    right,
};

/// Label configuration
pub const LabelConfig = struct {
    color: Style.Color = Style.Color.foreground,
    alignment: Alignment = .left,
    /// Padding inside the label area
    padding: u32 = 0,
};

/// Draw a label at the current layout position
pub fn label(ctx: *Context, text: []const u8) void {
    labelEx(ctx, text, .{});
}

/// Draw a label with custom configuration
pub fn labelEx(ctx: *Context, text: []const u8, config: LabelConfig) void {
    const bounds = ctx.layout.nextRect();
    labelRect(ctx, bounds, text, config);
}

/// Draw a label in a specific rectangle
pub fn labelRect(ctx: *Context, bounds: Layout.Rect, text: []const u8, config: LabelConfig) void {
    if (bounds.isEmpty()) return;

    const inner = bounds.shrink(config.padding);
    if (inner.isEmpty()) return;

    // Calculate text position based on alignment
    // Assume 8 pixels per character (bitmap font)
    const char_width: u32 = 8;
    const text_width = @as(u32, @intCast(text.len)) * char_width;

    const x: i32 = switch (config.alignment) {
        .left => inner.x,
        .center => inner.x + @as(i32, @intCast((inner.w -| text_width) / 2)),
        .right => inner.x + @as(i32, @intCast(inner.w -| text_width)),
    };

    // Center vertically (assume 8 pixel font height)
    const char_height: u32 = 8;
    const y = inner.y + @as(i32, @intCast((inner.h -| char_height) / 2));

    ctx.pushCommand(Command.text(x, y, text, config.color));
}

/// Draw a colored label (convenience function)
pub fn labelColored(ctx: *Context, text: []const u8, color: Style.Color) void {
    labelEx(ctx, text, .{ .color = color });
}

/// Draw a centered label (convenience function)
pub fn labelCentered(ctx: *Context, text: []const u8) void {
    labelEx(ctx, text, .{ .alignment = .center });
}

// =============================================================================
// Tests
// =============================================================================

test "label generates text command" {
    var ctx = try Context.init(std.testing.allocator, 800, 600);
    defer ctx.deinit();

    ctx.beginFrame();
    ctx.layout.row_height = 20;

    label(&ctx, "Hello");

    try std.testing.expectEqual(@as(usize, 1), ctx.commands.items.len);
    switch (ctx.commands.items[0]) {
        .text => |t| {
            try std.testing.expectEqualStrings("Hello", t.text);
        },
        else => unreachable,
    }

    ctx.endFrame();
}

test "label alignment" {
    var ctx = try Context.init(std.testing.allocator, 800, 600);
    defer ctx.deinit();

    ctx.beginFrame();
    ctx.layout.row_height = 20;

    // Left aligned (default)
    labelEx(&ctx, "Left", .{ .alignment = .left });

    // The text should start at x=0
    switch (ctx.commands.items[0]) {
        .text => |t| {
            try std.testing.expectEqual(@as(i32, 0), t.x);
        },
        else => unreachable,
    }

    ctx.endFrame();
}