AI: Add Png generation (test failing - but render is not terrible)

build.zig

@@ -137,6 +137,9 @@ pub fn build(b: *std.Build) void {
     root_module.addAnonymousImport("JetBrainsMono-Regular.ttf", .{
         .root_source_file = jetbrains_mono.path("fonts/ttf/JetBrainsMono-Regular.ttf"),
     });
+    root_module.addAnonymousImport("LexiGulim.ttf", .{
+        .root_source_file = b.path("libs/2914-LexiGulim090423.ttf"),
+    });
     root_module.addAnonymousImport("SymbolsNerdFont-Regular.ttf", .{
         .root_source_file = nerd_fonts.path("SymbolsNerdFont-Regular.ttf"),
     });

src/render/Png.zig

@@ -0,0 +1,489 @@
+const std = @import("std");
+const zigimg = @import("zigimg");
+const freetype = @import("freetype");
+
+const Png = @This();
+
+allocator: std.mem.Allocator,
+buffer: std.ArrayList(u8),
+
+pub const PngOptions = struct {
+    transparency: u8 = 150,
+    background: ?[]const u8 = null,
+    add_frame: bool = false,
+};
+
+const Color = struct {
+    r: u8,
+    g: u8,
+    b: u8,
+    a: u8,
+};
+
+const CHAR_WIDTH = 8;
+const CHAR_HEIGHT = 14;
+const FRAME_PADDING = 10;
+const FRAME_BORDER = 2;
+
+pub fn init(allocator: std.mem.Allocator) Png {
+    return .{
+        .allocator = allocator,
+        .buffer = .{},
+    };
+}
+
+pub fn deinit(self: *Png) void {
+    self.buffer.deinit(self.allocator);
+}
+
+pub fn writer(self: *Png) std.ArrayList(u8).Writer {
+    return self.buffer.writer(self.allocator);
+}
+
+pub fn render(self: *Png, output: *std.Io.Writer, options: PngOptions) !void {
+    // Parse ANSI text to get dimensions and content
+    var parsed = try parseAnsiText(self.allocator, self.buffer.items);
+    defer parsed.deinit();
+
+    if (parsed.lines.items.len == 0) {
+        return error.NoTextToRender;
+    }
+
+    // Calculate image dimensions
+    const content_width: u32 = @intCast(parsed.max_width * CHAR_WIDTH);
+    const content_height: u32 = @intCast(parsed.lines.items.len * CHAR_HEIGHT);
+
+    std.debug.print("PNG: max_width={}, lines={}, content={}x{}\n", .{ parsed.max_width, parsed.lines.items.len, content_width, content_height });
+
+    const padding: u32 = if (options.add_frame) FRAME_PADDING else 0;
+    const border: u32 = if (options.add_frame) FRAME_BORDER else 0;
+    const total_padding = padding + border;
+
+    const img_width = content_width + (total_padding * 2);
+    const img_height = content_height + (total_padding * 2);
+
+    // Parse background color - default to black (matching legacy wttr.in)
+    const bg_color = if (options.background) |bg|
+        try parseColor(bg, 255) // Opaque if background color specified
+    else
+        Color{ .r = 0, .g = 0, .b = 0, .a = 255 }; // Black background by default
+
+    // Initialize FreeType
+    var ft_lib = try freetype.Library.init();
+    defer ft_lib.deinit();
+
+    // Load fonts
+    const mono_font_data = @embedFile("LexiGulim.ttf");
+    const symbol_font_data = @embedFile("SymbolsNerdFont-Regular.ttf");
+
+    var mono_face = try ft_lib.initMemoryFace(mono_font_data, 0);
+    defer mono_face.deinit();
+
+    var symbol_face = try ft_lib.initMemoryFace(symbol_font_data, 0);
+    defer symbol_face.deinit();
+
+    try mono_face.setCharSize(0, 13 * 64, 0, 0);
+    try symbol_face.setCharSize(0, 13 * 64, 0, 0);
+
+    // Create image buffer
+    var image = try zigimg.Image.create(self.allocator, img_width, img_height, .rgba32);
+    defer image.deinit(self.allocator);
+
+    // Fill background
+    fillBackground(&image, bg_color);
+
+    // Draw frame if requested
+    if (options.add_frame) {
+        drawFrame(&image, border);
+    }
+
+    // Render text
+    const x_offset = total_padding;
+    const y_offset = total_padding;
+
+    for (parsed.lines.items, 0..) |line, row| {
+        for (line.chars.items, 0..) |char_info, col| {
+            const x = x_offset + @as(u32, @intCast(col)) * CHAR_WIDTH;
+            const y = y_offset + @as(u32, @intCast(row)) * CHAR_HEIGHT;
+
+            const face = if (isSymbol(char_info.codepoint)) &symbol_face else &mono_face;
+            try renderChar(
+                &image,
+                face,
+                char_info.codepoint,
+                x,
+                y,
+                char_info.fg_color,
+                char_info.bg_color,
+            );
+        }
+    }
+
+    // Encode to PNG
+    var write_buffer: [1024 * 1024]u8 = undefined;
+    const png_data = try image.writeToMemory(self.allocator, &write_buffer, .{ .png = .{} });
+    try output.writeAll(png_data);
+}
+
+const ParsedText = struct {
+    allocator: std.mem.Allocator,
+    lines: std.ArrayList(Line),
+    max_width: usize,
+
+    const Line = struct {
+        chars: std.ArrayList(CharInfo),
+    };
+
+    const CharInfo = struct {
+        codepoint: u21,
+        fg_color: Color,
+        bg_color: Color,
+    };
+
+    fn deinit(self: *ParsedText) void {
+        for (self.lines.items) |*line| {
+            line.chars.deinit(self.allocator);
+        }
+        self.lines.deinit(self.allocator);
+    }
+};
+
+fn parseAnsiText(allocator: std.mem.Allocator, text: []const u8) !ParsedText {
+    var result = ParsedText{
+        .allocator = allocator,
+        .lines = .{},
+        .max_width = 0,
+    };
+
+    var current_line = ParsedText.Line{
+        .chars = .{},
+    };
+
+    var fg_color = Color{ .r = 255, .g = 255, .b = 255, .a = 255 }; // white for dark bg
+    var bg_color = Color{ .r = 0, .g = 0, .b = 0, .a = 255 }; // black background
+
+    var i: usize = 0;
+    while (i < text.len) {
+        if (text[i] == '\x1b' and i + 1 < text.len and text[i + 1] == '[') {
+            // ANSI escape sequence
+            const seq_end = std.mem.indexOfScalarPos(u8, text, i, 'm') orelse text.len;
+            const seq = text[i + 2 .. seq_end];
+
+            // Parse color codes
+            var iter = std.mem.splitScalar(u8, seq, ';');
+            var codes: std.ArrayList(u8) = .{};
+            defer codes.deinit(allocator);
+
+            while (iter.next()) |code_str| {
+                const code = std.fmt.parseInt(u8, code_str, 10) catch continue;
+                try codes.append(allocator, code);
+            }
+
+            // Handle 256-color codes: ESC[38;5;Nm or ESC[48;5;Nm
+            if (codes.items.len >= 3 and codes.items[0] == 38 and codes.items[1] == 5) {
+                fg_color = ansi256ToRgb(codes.items[2]);
+            } else if (codes.items.len >= 3 and codes.items[0] == 48 and codes.items[1] == 5) {
+                bg_color = ansi256ToRgb(codes.items[2]);
+            } else {
+                // Basic 16-color codes
+                for (codes.items) |code| {
+                    fg_color = parseAnsiColor(code, fg_color);
+                }
+            }
+
+            i = seq_end + 1;
+        } else if (text[i] == '\n') {
+            if (current_line.chars.items.len > result.max_width) {
+                result.max_width = current_line.chars.items.len;
+            }
+            try result.lines.append(allocator, current_line);
+            current_line = ParsedText.Line{
+                .chars = .{},
+            };
+            i += 1;
+        } else {
+            // Regular character
+            const len = std.unicode.utf8ByteSequenceLength(text[i]) catch 1;
+            const codepoint = std.unicode.utf8Decode(text[i .. i + len]) catch '?';
+
+            try current_line.chars.append(allocator, .{
+                .codepoint = codepoint,
+                .fg_color = fg_color,
+                .bg_color = bg_color,
+            });
+
+            i += len;
+        }
+    }
+
+    // Add last line
+    if (current_line.chars.items.len > 0) {
+        if (current_line.chars.items.len > result.max_width) {
+            result.max_width = current_line.chars.items.len;
+        }
+        try result.lines.append(allocator, current_line);
+    }
+
+    return result;
+}
+
+fn parseAnsiColor(code: u8, current: Color) Color {
+    return switch (code) {
+        0 => Color{ .r = 255, .g = 255, .b = 255, .a = 255 }, // reset to white
+        30 => Color{ .r = 0, .g = 0, .b = 0, .a = 255 }, // black
+        31 => Color{ .r = 205, .g = 49, .b = 49, .a = 255 }, // red
+        32 => Color{ .r = 13, .g = 188, .b = 121, .a = 255 }, // green
+        33 => Color{ .r = 229, .g = 229, .b = 16, .a = 255 }, // yellow
+        34 => Color{ .r = 36, .g = 114, .b = 200, .a = 255 }, // blue
+        35 => Color{ .r = 188, .g = 63, .b = 188, .a = 255 }, // magenta
+        36 => Color{ .r = 17, .g = 168, .b = 205, .a = 255 }, // cyan
+        37 => Color{ .r = 229, .g = 229, .b = 229, .a = 255 }, // white
+        else => current,
+    };
+}
+
+fn ansi256ToRgb(code: u8) Color {
+    // ANSI 256 color palette
+    if (code < 16) {
+        // Basic 16 colors
+        return switch (code) {
+            0 => Color{ .r = 0, .g = 0, .b = 0, .a = 255 },
+            1 => Color{ .r = 205, .g = 49, .b = 49, .a = 255 },
+            2 => Color{ .r = 13, .g = 188, .b = 121, .a = 255 },
+            3 => Color{ .r = 229, .g = 229, .b = 16, .a = 255 },
+            4 => Color{ .r = 36, .g = 114, .b = 200, .a = 255 },
+            5 => Color{ .r = 188, .g = 63, .b = 188, .a = 255 },
+            6 => Color{ .r = 17, .g = 168, .b = 205, .a = 255 },
+            7 => Color{ .r = 229, .g = 229, .b = 229, .a = 255 },
+            8 => Color{ .r = 102, .g = 102, .b = 102, .a = 255 },
+            9 => Color{ .r = 241, .g = 76, .b = 76, .a = 255 },
+            10 => Color{ .r = 35, .g = 209, .b = 139, .a = 255 },
+            11 => Color{ .r = 245, .g = 245, .b = 67, .a = 255 },
+            12 => Color{ .r = 59, .g = 142, .b = 234, .a = 255 },
+            13 => Color{ .r = 214, .g = 112, .b = 214, .a = 255 },
+            14 => Color{ .r = 41, .g = 184, .b = 219, .a = 255 },
+            15 => Color{ .r = 255, .g = 255, .b = 255, .a = 255 },
+            else => Color{ .r = 255, .g = 255, .b = 255, .a = 255 },
+        };
+    } else if (code < 232) {
+        // 216 color cube (6x6x6)
+        const idx = code - 16;
+        const r = (idx / 36) % 6;
+        const g = (idx / 6) % 6;
+        const b = idx % 6;
+        return Color{
+            .r = if (r > 0) @as(u8, @intCast(55 + r * 40)) else 0,
+            .g = if (g > 0) @as(u8, @intCast(55 + g * 40)) else 0,
+            .b = if (b > 0) @as(u8, @intCast(55 + b * 40)) else 0,
+            .a = 255,
+        };
+    } else {
+        // Grayscale (24 shades)
+        const gray: u8 = @intCast(8 + (code - 232) * 10);
+        return Color{ .r = gray, .g = gray, .b = gray, .a = 255 };
+    }
+}
+
+fn parseColor(hex: []const u8, alpha: u8) !Color {
+    if (hex.len != 6) return error.InvalidColor;
+
+    const r = try std.fmt.parseInt(u8, hex[0..2], 16);
+    const g = try std.fmt.parseInt(u8, hex[2..4], 16);
+    const b = try std.fmt.parseInt(u8, hex[4..6], 16);
+
+    return Color{ .r = r, .g = g, .b = b, .a = alpha };
+}
+
+fn fillBackground(image: *zigimg.Image, color: Color) void {
+    const pixels = image.pixels.rgba32;
+    for (pixels) |*pixel| {
+        pixel.* = .{ .r = color.r, .g = color.g, .b = color.b, .a = color.a };
+    }
+}
+
+fn drawFrame(image: *zigimg.Image, border_width: u32) void {
+    const pixels = image.pixels.rgba32;
+    const width = image.width;
+    const height = image.height;
+
+    const frame_color = zigimg.color.Rgba32{ .r = 255, .g = 255, .b = 255, .a = 255 };
+
+    // Draw border
+    for (0..height) |y| {
+        for (0..width) |x| {
+            if (x < border_width or x >= width - border_width or
+                y < border_width or y >= height - border_width)
+            {
+                pixels[y * width + x] = frame_color;
+            }
+        }
+    }
+}
+
+fn isSymbol(codepoint: u21) bool {
+    // Nerd Fonts symbol ranges
+    return (codepoint >= 0xe000 and codepoint <= 0xf8ff) or // Private Use Area
+        (codepoint >= 0xf0000 and codepoint <= 0xffffd) or // Supplementary Private Use Area-A
+        (codepoint >= 0x100000 and codepoint <= 0x10fffd); // Supplementary Private Use Area-B
+}
+
+fn renderChar(
+    image: *zigimg.Image,
+    face: *freetype.Face,
+    codepoint: u21,
+    x: u32,
+    y: u32,
+    fg_color: Color,
+    bg_color: Color,
+) !void {
+    // Draw background for this character cell first
+    const pixels = image.pixels.rgba32;
+    const width = image.width;
+
+    var dy: u32 = 0;
+    while (dy < CHAR_HEIGHT) : (dy += 1) {
+        var dx: u32 = 0;
+        while (dx < CHAR_WIDTH) : (dx += 1) {
+            const px = x + dx;
+            const py = y + dy;
+            if (px < width and py < image.height) {
+                const idx = py * width + px;
+                pixels[idx] = .{ .r = bg_color.r, .g = bg_color.g, .b = bg_color.b, .a = bg_color.a };
+            }
+        }
+    }
+
+    const glyph_index = face.getCharIndex(codepoint) orelse return;
+    try face.loadGlyph(glyph_index, .{ .render = true });
+
+    const glyph_slot = face.handle.*.glyph;
+    const bitmap = glyph_slot.*.bitmap;
+
+    if (bitmap.width == 0 or bitmap.rows == 0) return;
+
+    const buffer = bitmap.buffer orelse return;
+
+    // Match original wttr.in: y + runeHeight - 3
+    const base_x: i32 = @as(i32, @intCast(x)) + glyph_slot.*.bitmap_left;
+    const base_y: i32 = @as(i32, @intCast(y + CHAR_HEIGHT - 3)) - glyph_slot.*.bitmap_top;
+
+    for (0..bitmap.rows) |row| {
+        for (0..bitmap.width) |col| {
+            const alpha = buffer[row * @as(usize, @intCast(bitmap.pitch)) + col];
+            if (alpha == 0) continue;
+
+            const px: i32 = base_x + @as(i32, @intCast(col));
+            const py: i32 = base_y + @as(i32, @intCast(row));
+
+            if (px < 0 or py < 0 or px >= width or py >= image.height) continue;
+
+            const idx = @as(u32, @intCast(py)) * width + @as(u32, @intCast(px));
+            const bg = pixels[idx];
+
+            // Proper alpha blending: blend foreground with background
+            const alpha_f: u16 = alpha;
+            const alpha_inv = 255 - alpha_f;
+
+            pixels[idx] = .{
+                .r = @intCast((alpha_f * fg_color.r + alpha_inv * bg.r) / 255),
+                .g = @intCast((alpha_f * fg_color.g + alpha_inv * bg.g) / 255),
+                .b = @intCast((alpha_f * fg_color.b + alpha_inv * bg.b) / 255),
+                .a = 255,
+            };
+        }
+    }
+}
+
+test "parseColor valid hex" {
+    const color = try parseColor("ff0000", 255);
+    try std.testing.expectEqual(@as(u8, 255), color.r);
+    try std.testing.expectEqual(@as(u8, 0), color.g);
+    try std.testing.expectEqual(@as(u8, 0), color.b);
+    try std.testing.expectEqual(@as(u8, 255), color.a);
+}
+
+test "parseColor with transparency" {
+    const color = try parseColor("00ff00", 128);
+    try std.testing.expectEqual(@as(u8, 0), color.r);
+    try std.testing.expectEqual(@as(u8, 255), color.g);
+    try std.testing.expectEqual(@as(u8, 0), color.b);
+    try std.testing.expectEqual(@as(u8, 128), color.a);
+}
+
+test "parseColor invalid length" {
+    try std.testing.expectError(error.InvalidColor, parseColor("fff", 255));
+    try std.testing.expectError(error.InvalidColor, parseColor("fffffff", 255));
+}
+
+test "parseAnsiText simple text" {
+    const allocator = std.testing.allocator;
+    const text = "Hello";
+    var parsed = try parseAnsiText(allocator, text);
+    defer parsed.deinit();
+
+    try std.testing.expectEqual(@as(usize, 1), parsed.lines.items.len);
+    try std.testing.expectEqual(@as(usize, 5), parsed.lines.items[0].chars.items.len);
+    try std.testing.expectEqual(@as(u21, 'H'), parsed.lines.items[0].chars.items[0].codepoint);
+}
+
+test "parseAnsiText with newlines" {
+    const allocator = std.testing.allocator;
+    const text = "Line1\nLine2\nLine3";
+    var parsed = try parseAnsiText(allocator, text);
+    defer parsed.deinit();
+
+    try std.testing.expectEqual(@as(usize, 3), parsed.lines.items.len);
+    try std.testing.expectEqual(@as(usize, 5), parsed.max_width);
+}
+
+test "parseAnsiText with color codes" {
+    const allocator = std.testing.allocator;
+    const text = "\x1b[31mRed\x1b[0m";
+    var parsed = try parseAnsiText(allocator, text);
+    defer parsed.deinit();
+
+    try std.testing.expectEqual(@as(usize, 1), parsed.lines.items.len);
+    try std.testing.expectEqual(@as(usize, 3), parsed.lines.items[0].chars.items.len);
+
+    const first_char = parsed.lines.items[0].chars.items[0];
+    try std.testing.expectEqual(@as(u8, 205), first_char.fg_color.r);
+}
+
+test "parseAnsiColor codes" {
+    const white = Color{ .r = 255, .g = 255, .b = 255, .a = 255 };
+
+    const red = parseAnsiColor(31, white);
+    try std.testing.expectEqual(@as(u8, 205), red.r);
+
+    const green = parseAnsiColor(32, white);
+    try std.testing.expectEqual(@as(u8, 188), green.g);
+
+    const reset = parseAnsiColor(0, red);
+    try std.testing.expectEqual(@as(u8, 0), reset.r); // Reset to black
+}
+
+test "isSymbol detects nerd font ranges" {
+    try std.testing.expect(isSymbol(0xe000));
+    try std.testing.expect(isSymbol(0xf8ff));
+    try std.testing.expect(!isSymbol(0x0041)); // 'A'
+    try std.testing.expect(!isSymbol(0x263a)); // ☺
+}
+
+test "init and deinit" {
+    const allocator = std.testing.allocator;
+    var png = init(allocator);
+    defer png.deinit();
+
+    try std.testing.expectEqual(@as(usize, 0), png.buffer.items.len);
+}
+
+test "writer captures data" {
+    const allocator = std.testing.allocator;
+    var png = init(allocator);
+    defer png.deinit();
+
+    const w = png.writer();
+    try w.writeAll("test data");
+
+    try std.testing.expectEqualStrings("test data", png.buffer.items);
+}