Implement basic color parsing for some things

zig/sdl/hello_sdl.zig

    }
    fn toArgv(cmd: []const u8) []const []const u8 {
        _ = std.fmt.bufPrint(&cmd_buf, "{s}\x00", .{cmd["man ".len..]}) catch "???";
        return &[_][]const u8{ "man", &cmd_buf };
        _ = std.fmt.bufPrint(&cmd_buf, "MAN_KEEP_FORMATTING=yesplease man {s}\x00", .{cmd["man ".len..]}) catch "???";
        return &[_][]const u8{ "bash", "-c", &cmd_buf };
    }
};
    fn toArgv(cmd: []const u8) []const []const u8 {
        _ = std.fmt.bufPrint(&cmd_buf, "{s}\x00", .{cmd["s ".len..]}) catch "???";
        argv_buf[0] = "ag";
        argv_buf[1] = &cmd_buf;
        argv_buf[1] = "--color";
        argv_buf[2] = "--unrestricted";
        argv_buf[3] = &cmd_buf;
        for (Config.searchDirectories) |dir, i| {
            argv_buf[2 + i] = dir;
            argv_buf[4 + i] = dir;
        }
        return argv_buf[0 .. 2 + Config.searchDirectories.len];
        return argv_buf[0 .. 4 + Config.searchDirectories.len];
    }
};
    defer c.TTF_CloseFont(font);
    c.SDL_Log("Using font %s", font_file.ptr);
    var bold_font_file = if (args.len > 2) args[2] else "/usr/share/fonts/TTF/FantasqueSansMono-Bold.ttf";
    const bold_font = c.TTF_OpenFont(bold_font_file, 16) orelse {
        c.SDL_Log("Unable to load font: %s", c.TTF_GetError());
        return error.TTFInitializationFailed;
    };
    defer c.TTF_CloseFont(bold_font);
    // assume monospace font
    var glyph_width: c_int = 0;
    if (c.TTF_GlyphMetrics(font, 'g', null, null, null, null, &glyph_width) != 0) {
        var i: c_int = 1;
        var line_buf = [_]u8{0} ** 10000;
        var part_buf = [_]u8{0} ** 10000;
        for (commands) |*command| {
            if (!command.isActive(cmd)) {
                continue;
                _ = std.mem.replace(u8, skipped_line, "\t", " " ** 8, &line_buf);
                line_buf[repl_size] = 0;
                var j: c_int = 0;
                // TODO: implement some terminal colors
                var parts = std.mem.split(u8, line_buf[0..repl_size], "\x1B[");
                var part = parts.next();
                while (part != null and part.?.len != repl_size) : (part = parts.next()) {
                    if (part.?.len > 0) {
                        std.debug.print("escape char: {d} {s}\n", .{ part.?[0], part.?[0..] });
                while (part != null) : (part = parts.next()) {
                    var fnt = font;
                    var fg_color = white;
                    var bg_color = black;
                    var part_text = part.?;
                    if (std.mem.startsWith(u8, part_text, "0m")) {
                        part_text = part_text[2..];
                    } else if (std.mem.startsWith(u8, part_text, "1;32m")) {
                        fnt = bold_font;
                        part_text = part_text[5..];
                        fg_color = c.SDL_Color{ .r = 0, .g = 205, .b = 0, .a = 255 };
                    } else if (std.mem.startsWith(u8, part_text, "1;33m")) {
                        fnt = bold_font;
                        part_text = part_text[5..];
                        fg_color = c.SDL_Color{ .r = 205, .g = 205, .b = 0, .a = 255 };
                    } else if (std.mem.startsWith(u8, part_text, "30;43m")) {
                        part_text = part_text[6..];
                        bg_color = c.SDL_Color{ .r = 205, .g = 205, .b = 0, .a = 255 };
                    } else if (std.mem.startsWith(u8, part_text, "K")) {
                        // no idea what this is, skipping it
                        part_text = part_text[1..];
                    } else {
                        if (part.?.len > 0) {
                            //std.debug.print("unhandled escape char: {d} {s}\n", .{ part.?[0], part.?[0..] });
                        }
                    }
                }
                const result_text = c.TTF_RenderUTF8_Shaded(font, &line_buf, white, black);
                const result_texture = c.SDL_CreateTextureFromSurface(renderer, result_text);
                _ = c.SDL_RenderCopy(renderer, result_texture, null, &c.SDL_Rect{ .x = 0, .y = i * glyph_height, .w = @intCast(c_int, repl_size) * glyph_width, .h = glyph_height });
                c.SDL_FreeSurface(result_text);
                c.SDL_DestroyTexture(result_texture);
                    var k = j;
                    var l: usize = 0;
                    var skip_next = false;
                    var was_overdraw = false;
                    for (part_text) |ch, p| {
                        if (skip_next) {
                            skip_next = false;
                            continue;
                        }
                        if (ch == 8 and p + 1 < part_text.len) {
                            //std.debug.print("overdraw '{c}'\n", .{part_text[p + 1]});
                            const result_text = c.TTF_RenderUTF8_Shaded(font, &[_]u8{ part_text[p + 1], 0 }, fg_color, bg_color);
                            const result_texture = c.SDL_CreateTextureFromSurface(renderer, result_text);
                            _ = c.SDL_RenderCopy(renderer, result_texture, null, &c.SDL_Rect{ .x = (k - 1) * glyph_width, .y = i * glyph_height, .w = @intCast(c_int, 1) * glyph_width, .h = glyph_height });
                            c.SDL_FreeSurface(result_text);
                            c.SDL_DestroyTexture(result_texture);
                            skip_next = true;
                            was_overdraw = true;
                        } else {
                            part_buf[l] = ch;
                            l += 1;
                            k += 1;
                        }
                    }
                    part_buf[l] = 0;
                    const result_text = c.TTF_RenderUTF8_Shaded(fnt, &part_buf, fg_color, bg_color);
                    const result_texture = c.SDL_CreateTextureFromSurface(renderer, result_text);
                    if (was_overdraw and c.SDL_SetTextureBlendMode(result_texture, c.SDL_BLENDMODE_ADD) != 0) {
                        c.SDL_Log("Unable set texture blend mode: %s", c.SDL_GetError());
                    }
                    _ = c.SDL_RenderCopy(renderer, result_texture, null, &c.SDL_Rect{ .x = j * glyph_width, .y = i * glyph_height, .w = @intCast(c_int, l) * glyph_width, .h = glyph_height });
                    c.SDL_FreeSurface(result_text);
                    c.SDL_DestroyTexture(result_texture);
                    j += @intCast(c_int, part_text.len);
                }
                i += 1;
                line = lines.next();