#include "ui.h"

#include <stdio.h>
#include <string.h>

static const char *FONT_CANDIDATES[] = {
    "BigBlueTermPlus Nerd Font Mono.ttf",
    "BigBlueTermPlusNerdFontMono-Regular.ttf",
    "/usr/share/fonts/truetype/dejavu/DejaVuSansMono.ttf",
    "/usr/share/fonts/TTF/DejaVuSansMono.ttf",
    "/usr/share/fonts/truetype/liberation2/LiberationMono-Regular.ttf"
};

static void fill_rect(SDL_Renderer *renderer, const SDL_Rect *rect, SDL_Color color);
static SDL_Texture *text_to_texture(SDL_Renderer *renderer, TTF_Font *font, const char *text, SDL_Color color, int *width, int *height);

static void text_texture_destroy(UiTextTexture *text_texture) {
    if (!text_texture) {
        return;
    }

    if (text_texture->texture) {
        SDL_DestroyTexture(text_texture->texture);
    }
    memset(text_texture, 0, sizeof(*text_texture));
}

static int text_texture_init(UiTextTexture *text_texture,
                             SDL_Renderer *renderer,
                             TTF_Font *font,
                             const char *text,
                             SDL_Color color) {
    if (!text_texture) {
        return -1;
    }

    memset(text_texture, 0, sizeof(*text_texture));
    text_texture->texture = text_to_texture(renderer, font, text, color, &text_texture->width, &text_texture->height);
    return text_texture->texture ? 0 : -1;
}

static void set_draw_color(SDL_Renderer *renderer, SDL_Color color) {
    SDL_SetRenderDrawColor(renderer, color.r, color.g, color.b, color.a);
}

static SDL_Color color_with_alpha(SDL_Color color, Uint8 alpha) {
    color.a = alpha;
    return color;
}

static SDL_Color blend_color(SDL_Color from, SDL_Color to, int weight_to_255) {
    SDL_Color blended;
    int weight_from = 255 - weight_to_255;

    blended.r = (Uint8) ((from.r * weight_from + to.r * weight_to_255) / 255);
    blended.g = (Uint8) ((from.g * weight_from + to.g * weight_to_255) / 255);
    blended.b = (Uint8) ((from.b * weight_from + to.b * weight_to_255) / 255);
    blended.a = 255;
    return blended;
}

static int color_luma(SDL_Color color) {
    return (299 * color.r + 587 * color.g + 114 * color.b) / 1000;
}

static SDL_Color readable_text_color(SDL_Color background) {
    return color_luma(background) < 120 ? COLOR_TEXT_LIGHT : COLOR_TEXT_DARK;
}

static SDL_Color ensure_contrast(SDL_Color preferred, SDL_Color background) {
    int diff = color_luma(preferred) - color_luma(background);
    if (diff < 0) {
        diff = -diff;
    }
    if (diff < 75) {
        return readable_text_color(background);
    }
    return preferred;
}

static SDL_Texture *text_to_texture(SDL_Renderer *renderer, TTF_Font *font, const char *text, SDL_Color color, int *width, int *height) {
    SDL_Surface *surface;
    SDL_Texture *texture;

    if (!font || !text || text[0] == '\0') {
        return NULL;
    }

    surface = TTF_RenderUTF8_Solid(font, text, color);
    if (!surface) {
        return NULL;
    }

    texture = SDL_CreateTextureFromSurface(renderer, surface);
    if (width) {
        *width = surface->w;
    }
    if (height) {
        *height = surface->h;
    }
    SDL_FreeSurface(surface);
    return texture;
}

static void draw_cached_text(SDL_Renderer *renderer, const UiTextTexture *text_texture, int x, int y) {
    SDL_Rect dst;

    if (!text_texture || !text_texture->texture) {
        return;
    }

    dst.x = x;
    dst.y = y;
    dst.w = text_texture->width;
    dst.h = text_texture->height;
    SDL_RenderCopy(renderer, text_texture->texture, NULL, &dst);
}

static void fill_three_stop_gradient(SDL_Renderer *renderer,
                                     const SDL_Rect *rect,
                                     SDL_Color top,
                                     SDL_Color middle,
                                     SDL_Color bottom) {
    int split;

    if (!rect || rect->h <= 0) {
        return;
    }

    top = blend_color(top, middle, 140);
    bottom = blend_color(bottom, middle, 140);

    split = rect->h / 2;
    for (int i = 0; i < rect->h; ++i) {
        SDL_Color from = i < split ? top : middle;
        SDL_Color to = i < split ? middle : bottom;
        int segment_height = i < split ? SDL_max(split, 1) : SDL_max(rect->h - split, 1);
        int segment_pos = i < split ? i : i - split;
        Uint8 r = (Uint8) (from.r + (to.r - from.r) * segment_pos / SDL_max(segment_height - 1, 1));
        Uint8 g = (Uint8) (from.g + (to.g - from.g) * segment_pos / SDL_max(segment_height - 1, 1));
        Uint8 b = (Uint8) (from.b + (to.b - from.b) * segment_pos / SDL_max(segment_height - 1, 1));
        SDL_SetRenderDrawColor(renderer, r, g, b, 255);
        SDL_RenderDrawLine(renderer, rect->x, rect->y + i, rect->x + rect->w, rect->y + i);
    }
}

static void fill_rect_alpha(SDL_Renderer *renderer, const SDL_Rect *rect, SDL_Color color) {
    SDL_SetRenderDrawBlendMode(renderer, SDL_BLENDMODE_BLEND);
    SDL_SetRenderDrawColor(renderer, color.r, color.g, color.b, color.a);
    SDL_RenderFillRect(renderer, rect);
    SDL_SetRenderDrawBlendMode(renderer, SDL_BLENDMODE_NONE);
}

static void draw_panel_shadow(SDL_Renderer *renderer, const SDL_Rect *rect) {
    SDL_Rect shadow = {rect->x + 6, rect->y + 6, rect->w, rect->h};
    fill_rect_alpha(renderer, &shadow, color_with_alpha(COLOR_PANEL_SHADOW, 48));
}

static void draw_gloss_line(SDL_Renderer *renderer, const SDL_Rect *rect, SDL_Color gloss_color) {
    SDL_Rect gloss = {rect->x + 4, rect->y + 1, SDL_max(rect->w - 8, 0), 2};
    if (gloss.w > 0) {
        fill_rect_alpha(renderer, &gloss, gloss_color);
    }
}

static void draw_panel_bevel(SDL_Renderer *renderer, const SDL_Rect *rect, SDL_Color gloss_color) {
    SDL_Rect top_white = {rect->x + 8, rect->y, SDL_max(rect->w - 16, 0), 1};
    SDL_Rect top_black = {rect->x + 8, rect->y + 1, SDL_max(rect->w - 16, 0), 1};

    if (top_white.w > 0) {
        fill_rect_alpha(renderer, &top_white, color_with_alpha(gloss_color, 72));
        fill_rect_alpha(renderer, &top_black, (SDL_Color){0, 0, 0, 28});
    }
}

static void stroke_rect_alpha(SDL_Renderer *renderer, const SDL_Rect *rect, SDL_Color color) {
    SDL_SetRenderDrawBlendMode(renderer, SDL_BLENDMODE_BLEND);
    SDL_SetRenderDrawColor(renderer, color.r, color.g, color.b, color.a);
    SDL_RenderDrawRect(renderer, rect);
    SDL_SetRenderDrawBlendMode(renderer, SDL_BLENDMODE_NONE);
}

static void draw_selection_glow(SDL_Renderer *renderer, const SDL_Rect *rect, SDL_Color edge) {
    SDL_Rect outer = *rect;
    SDL_Rect inner = {rect->x + 1, rect->y + 1, rect->w - 2, rect->h - 2};
    stroke_rect_alpha(renderer, &outer, color_with_alpha(edge, 62));
    if (inner.w > 0 && inner.h > 0) {
        stroke_rect_alpha(renderer, &inner, color_with_alpha(edge, 34));
    }
}

static void draw_rounded_top_panel(SDL_Renderer *renderer, const SDL_Rect *rect, SDL_Color fill_color, SDL_Color border_color, int radius) {
    SDL_Rect body;
    SDL_Rect top;

    if (!rect || rect->w < radius || rect->h < radius) {
        return;
    }

    body = (SDL_Rect){rect->x, rect->y + radius, rect->w, rect->h - radius};
    top = (SDL_Rect){rect->x + radius, rect->y, rect->w - radius * 2, radius};
    fill_rect(renderer, &body, fill_color);
    fill_rect(renderer, &top, fill_color);
    fill_rect(renderer, &(SDL_Rect){rect->x + radius / 2, rect->y + 2, rect->w - radius, radius - 2}, fill_color);
    fill_rect(renderer, &(SDL_Rect){rect->x + 2, rect->y + radius / 2, rect->w - 4, radius / 2}, fill_color);

    set_draw_color(renderer, border_color);
    SDL_RenderDrawLine(renderer, rect->x + radius, rect->y, rect->x + rect->w - radius - 1, rect->y);
    SDL_RenderDrawLine(renderer, rect->x + radius / 2, rect->y + 2, rect->x + radius / 2 + 1, rect->y + 1);
    SDL_RenderDrawLine(renderer, rect->x + rect->w - radius / 2 - 2, rect->y + 1, rect->x + rect->w - radius / 2 - 1, rect->y + 2);
    SDL_RenderDrawLine(renderer, rect->x + 1, rect->y + radius - 2, rect->x + 1, rect->y + rect->h - 2);
    SDL_RenderDrawLine(renderer, rect->x + rect->w - 2, rect->y + radius - 2, rect->x + rect->w - 2, rect->y + rect->h - 2);
    SDL_RenderDrawLine(renderer, rect->x + 1, rect->y + rect->h - 1, rect->x + rect->w - 2, rect->y + rect->h - 1);
}

static void draw_beveled_bar(SDL_Renderer *renderer,
                             const SDL_Rect *rect,
                             SDL_Color top,
                             SDL_Color mid,
                             SDL_Color bottom,
                             SDL_Color top_edge,
                             SDL_Color bottom_edge) {
    if (!rect) {
        return;
    }

    fill_three_stop_gradient(renderer, rect, top, mid, bottom);
    top_edge = blend_color(top_edge, mid, 170);
    bottom_edge = blend_color(bottom_edge, mid, 170);
    SDL_SetRenderDrawBlendMode(renderer, SDL_BLENDMODE_BLEND);
    SDL_SetRenderDrawColor(renderer, top_edge.r, top_edge.g, top_edge.b, 110);
    SDL_RenderDrawLine(renderer, rect->x, rect->y, rect->x + rect->w - 1, rect->y);
    SDL_SetRenderDrawColor(renderer, bottom_edge.r, bottom_edge.g, bottom_edge.b, 110);
    SDL_RenderDrawLine(renderer, rect->x, rect->y + rect->h - 1, rect->x + rect->w - 1, rect->y + rect->h - 1);
    SDL_SetRenderDrawBlendMode(renderer, SDL_BLENDMODE_NONE);
}

static void draw_pill_button(SDL_Renderer *renderer, const GuideTheme *theme, const SDL_Rect *rect, SDL_Color fill, SDL_Color border) {
    SDL_Rect shadow;

    if (!rect || rect->w < 10 || rect->h < 10) {
        return;
    }

    shadow = (SDL_Rect){rect->x + 2, rect->y + 2, rect->w, rect->h};
    fill_rect_alpha(renderer, &shadow, theme->pill_shadow);
    draw_beveled_bar(renderer, rect, theme->pill_light, fill, fill, theme->gloss, border);
    set_draw_color(renderer, border);
    SDL_RenderDrawLine(renderer, rect->x + 4, rect->y, rect->x + rect->w - 5, rect->y);
    SDL_RenderDrawLine(renderer, rect->x + 4, rect->y + rect->h - 1, rect->x + rect->w - 5, rect->y + rect->h - 1);
    SDL_RenderDrawLine(renderer, rect->x, rect->y + 4, rect->x, rect->y + rect->h - 5);
    SDL_RenderDrawLine(renderer, rect->x + rect->w - 1, rect->y + 4, rect->x + rect->w - 1, rect->y + rect->h - 5);
}

static void draw_text_clipped(SDL_Renderer *renderer,
                              TTF_Font *font,
                              const char *text,
                              const SDL_Rect *clip_rect,
                              int x,
                              int y,
                              SDL_Color color) {
    SDL_Rect previous_clip;
    SDL_bool had_clip = SDL_RenderIsClipEnabled(renderer);
    if (had_clip) {
        SDL_RenderGetClipRect(renderer, &previous_clip);
    }
    SDL_RenderSetClipRect(renderer, clip_rect);
    {
        SDL_Texture *texture;
        int width = 0;
        int height = 0;
        SDL_Rect dst;

        texture = text_to_texture(renderer, font, text, color, &width, &height);
        if (texture) {
            dst.x = x;
            dst.y = y;
            dst.w = width;
            dst.h = height;
            SDL_RenderCopy(renderer, texture, NULL, &dst);
            SDL_DestroyTexture(texture);
        }
    }
    SDL_RenderSetClipRect(renderer, had_clip ? &previous_clip : NULL);
}

static void draw_text_shadowed(SDL_Renderer *renderer,
                               TTF_Font *font,
                               const char *text,
                               const SDL_Rect *clip_rect,
                               int x,
                               int y,
                               SDL_Color color,
                               SDL_Color shadow) {
    draw_text_clipped(renderer, font, text, clip_rect, x + 1, y + 1, shadow);
    draw_text_clipped(renderer, font, text, clip_rect, x, y, color);
}

static void fit_text_with_ellipsis(TTF_Font *font, const char *text, int max_width, char *out, size_t out_size) {
    int width = 0;
    size_t len;

    if (!out || out_size == 0) {
        return;
    }

    out[0] = '\0';
    if (!font || !text || max_width <= 0) {
        return;
    }

    if (TTF_SizeUTF8(font, text, &width, NULL) == 0 && width <= max_width) {
        snprintf(out, out_size, "%s", text);
        return;
    }

    len = strlen(text);
    while (len > 0) {
        snprintf(out, out_size, "%.*s...", (int) len, text);
        if (TTF_SizeUTF8(font, out, &width, NULL) == 0 && width <= max_width) {
            return;
        }
        len -= 1;
    }

    snprintf(out, out_size, "...");
}

static void format_time_compact(char *buffer, size_t buffer_size, time_t value) {
    struct tm local_time;
    localtime_r(&value, &local_time);
    strftime(buffer, buffer_size, "%I:%M %p", &local_time);
}

static void fill_rect(SDL_Renderer *renderer, const SDL_Rect *rect, SDL_Color color) {
    set_draw_color(renderer, color);
    SDL_RenderFillRect(renderer, rect);
}

static void stroke_rect(SDL_Renderer *renderer, const SDL_Rect *rect, SDL_Color color) {
    set_draw_color(renderer, color);
    SDL_RenderDrawRect(renderer, rect);
}

static SDL_Rect fit_rect(int outer_x, int outer_y, int outer_w, int outer_h, int inner_w, int inner_h) {
    SDL_Rect dst = {outer_x, outer_y, outer_w, outer_h};
    double scale;

    if (inner_w <= 0 || inner_h <= 0) {
        return dst;
    }

    scale = SDL_min((double) outer_w / (double) inner_w, (double) outer_h / (double) inner_h);
    dst.w = (int) (inner_w * scale);
    dst.h = (int) (inner_h * scale);
    dst.x = outer_x + (outer_w - dst.w) / 2;
    dst.y = outer_y + (outer_h - dst.h) / 2;
    return dst;
}

static void draw_video(SDL_Renderer *renderer, SDL_Texture *video_texture, int texture_width, int texture_height, SDL_Rect destination) {
    if (!video_texture) {
        fill_rect(renderer, &destination, COLOR_BLACK);
        return;
    }

    {
        SDL_Rect fitted = fit_rect(destination.x, destination.y, destination.w, destination.h, texture_width, texture_height);
        fill_rect(renderer, &destination, COLOR_BLACK);
        SDL_RenderCopy(renderer, video_texture, NULL, &fitted);
    }
}

static void format_clock_label(char *buffer, size_t buffer_size, time_t now, int minute_offset) {
    struct tm local_time;
    time_t slot = now + minute_offset * 60;
    localtime_r(&slot, &local_time);
    strftime(buffer, buffer_size, "%I:%M %p", &local_time);
}

static void draw_timeline_header_cached(SDL_Renderer *renderer, const UiCache *cache, const GuideTheme *theme, SDL_Rect rect) {
    int segments = 4;
    SDL_Color ribbon_text = ensure_contrast(theme->ribbon_text, theme->ribbon_mid);
    SDL_Color ribbon_shadow = color_luma(theme->ribbon_mid) < 120 ? color_with_alpha(COLOR_BLACK, 255) : color_with_alpha(COLOR_TEXT_LIGHT, 255);

    draw_beveled_bar(renderer,
                     &rect,
                     theme->ribbon_top,
                     theme->ribbon_mid,
                     theme->ribbon_bottom,
                     theme->gloss,
                     theme->panel_border);

    for (int i = 0; i < segments; ++i) {
        int x = rect.x + (rect.w * i) / segments;
        int centered_x = x - cache->timeline_labels[i].width / 2;
        SDL_Rect shadow_dst = {centered_x + 1, rect.y + 11, cache->timeline_labels[i].width, cache->timeline_labels[i].height};
        SDL_Rect text_dst = {centered_x, rect.y + 10, cache->timeline_labels[i].width, cache->timeline_labels[i].height};
        SDL_SetTextureColorMod(cache->timeline_labels[i].texture, ribbon_shadow.r, ribbon_shadow.g, ribbon_shadow.b);
        SDL_RenderCopy(renderer, cache->timeline_labels[i].texture, NULL, &shadow_dst);
        SDL_SetTextureColorMod(cache->timeline_labels[i].texture, ribbon_text.r, ribbon_text.g, ribbon_text.b);
        SDL_RenderCopy(renderer, cache->timeline_labels[i].texture, NULL, &text_dst);
        set_draw_color(renderer, theme->grid_line);
        SDL_RenderDrawLine(renderer, x, rect.y + rect.h - 2, x, rect.y + rect.h + 5 * 76);
    }
}

static void draw_status_bar(SDL_Renderer *renderer,
                            TTF_Font *font,
                            const GuideTheme *theme,
                            const Channel *selected_channel,
                            const SDL_Rect *rect,
                            time_t now_wall) {
    char clock_text[32];
    char channel_text[160];
    SDL_Color text_color;

    if (!rect) {
        return;
    }

    text_color = readable_text_color(theme->status_mid);

    draw_beveled_bar(renderer,
                     rect,
                     blend_color(theme->status_top, theme->status_mid, 220),
                     theme->status_mid,
                     blend_color(theme->status_bottom, theme->status_mid, 220),
                     color_with_alpha(theme->gloss, 36),
                     theme->panel_border);
    format_time_compact(clock_text, sizeof(clock_text), now_wall);
    draw_text_clipped(renderer, font, clock_text, rect, rect->x + 12, rect->y + 10, text_color);
    set_draw_color(renderer, theme->status_divider);
    SDL_RenderDrawLine(renderer, rect->x + rect->w / 2, rect->y + 8, rect->x + rect->w / 2, rect->y + rect->h - 8);

    if (selected_channel) {
        snprintf(channel_text, sizeof(channel_text), "%s  %d", selected_channel->name, selected_channel->number);
        draw_text_clipped(renderer, font, channel_text, rect, rect->x + rect->w - 260, rect->y + 10, text_color);
    }
}

static void draw_info_panel(SDL_Renderer *renderer,
                            const UiFonts *fonts,
                            const GuideTheme *theme,
                            const Channel *selected_channel,
                            const SDL_Rect *rect,
                            Uint64 app_start_ticks,
                            Uint64 now_ticks,
                            time_t now_wall) {
    SDL_Rect accent;
    SDL_Rect clip_rect;
    char time_range[64];
    char end_text[32];
    char description[384];
    time_t start_time;
    time_t end_time;
    double program_seek;
    const ProgramEntry *program;
    SDL_Color panel_text;

    if (!rect || !selected_channel) {
        return;
    }

    panel_text = ensure_contrast(theme->panel_text, theme->panel_fill);

    draw_panel_shadow(renderer, rect);
    draw_rounded_top_panel(renderer, rect, theme->panel_fill, theme->panel_border, theme->rounded_radius > 0 ? theme->rounded_radius : 8);
    accent = (SDL_Rect){rect->x + 1, rect->y + 1, rect->w - 2, 38};
    fill_rect(renderer, &accent, theme->panel_fill);
    draw_panel_bevel(renderer, rect, theme->gloss);
    stroke_rect(renderer, rect, theme->panel_border);

    program = channel_resolve_program(selected_channel, app_start_ticks, now_ticks, &program_seek, NULL);
    if (!program) {
        return;
    }
    start_time = now_wall - (time_t) program_seek;
    end_time = start_time + (time_t) program->duration_seconds;
    format_time_compact(time_range, sizeof(time_range), start_time);
    format_time_compact(end_text, sizeof(end_text), end_time);
    strncat(time_range, " - ", sizeof(time_range) - strlen(time_range) - 1);
    strncat(time_range, end_text, sizeof(time_range) - strlen(time_range) - 1);
    snprintf(description,
             sizeof(description),
             "%s",
             selected_channel->description[0] != '\0' ? selected_channel->description : "Local programming lineup.");

    clip_rect = (SDL_Rect){rect->x + 16, rect->y + 12, rect->w - 32, rect->h - 24};
    draw_text_clipped(renderer, fonts->large, selected_channel->name, &clip_rect, rect->x + 18, rect->y + 44, panel_text);
    draw_text_clipped(renderer, fonts->medium, program->program_title, &clip_rect, rect->x + 18, rect->y + 88, panel_text);
    draw_text_clipped(renderer, fonts->small, time_range, &clip_rect, rect->x + 18, rect->y + 124, panel_text);
    draw_text_clipped(renderer, fonts->small, description, &clip_rect, rect->x + 18, rect->y + 148, panel_text);
}

static void draw_grid_background(SDL_Renderer *renderer, const GuideTheme *theme, const SDL_Rect *grid_rect, int row_height, double pixels_per_minute) {
    fill_three_stop_gradient(renderer,
                             grid_rect,
                             theme->background_top,
                             theme->background_mid,
                             theme->background_bottom);

    for (int minute = 0; minute <= 90; minute += 30) {
        int x = GUIDE_X_START + (int) (minute * pixels_per_minute);
        SDL_Color strong_line = ensure_contrast(theme->grid_line, theme->background_mid);
        set_draw_color(renderer, strong_line);
        SDL_RenderDrawLine(renderer, x, grid_rect->y, x, grid_rect->y + grid_rect->h);
        SDL_RenderDrawLine(renderer, x + 1, grid_rect->y, x + 1, grid_rect->y + grid_rect->h);
    }

    for (int row = 0; row <= GUIDE_VISIBLE_ROWS; ++row) {
        int y = grid_rect->y + row * row_height;
        set_draw_color(renderer, theme->row_line_hi);
        SDL_RenderDrawLine(renderer, grid_rect->x, y, grid_rect->x + grid_rect->w, y);
        if (y + row_height - 1 <= grid_rect->y + grid_rect->h) {
            set_draw_color(renderer, theme->row_line_lo);
            SDL_RenderDrawLine(renderer, grid_rect->x, y + row_height - 1, grid_rect->x + grid_rect->w, y + row_height - 1);
        }
    }
}

static void draw_footer_legend(SDL_Renderer *renderer,
                               const UiFonts *fonts,
                               const GuideTheme *theme,
                               int window_width,
                               int window_height) {
    SDL_Rect footer = {0, window_height - 54, window_width, 54};
    SDL_Rect chip = {window_width / 2 - 180, window_height - 38, 34, 20};
    SDL_Color footer_text = readable_text_color(theme->footer_mid);

    fill_three_stop_gradient(renderer,
                             &footer,
                             blend_color(theme->footer_top, theme->footer_mid, 240),
                             theme->footer_mid,
                             blend_color(theme->footer_bottom, theme->footer_mid, 240));
    draw_gloss_line(renderer, &footer, color_with_alpha(theme->gloss, 20));
    stroke_rect(renderer, &footer, theme->panel_border);

    draw_pill_button(renderer, theme, &chip, theme->panel_fill, theme->panel_border);
    draw_text_clipped(renderer, fonts->medium, "A", &footer, chip.x + 11, chip.y + 1, footer_text);
    draw_text_clipped(renderer, fonts->small, "TIME", &footer, chip.x + 42, chip.y - 1, footer_text);

    chip.x += 144;
    draw_pill_button(renderer, theme, &chip, theme->block_mid, theme->panel_border);
    draw_text_clipped(renderer, fonts->medium, "B", &footer, chip.x + 11, chip.y + 1, footer_text);
    draw_text_clipped(renderer, fonts->small, "THEME", &footer, chip.x + 42, chip.y - 1, footer_text);

    chip.x += 150;
    draw_pill_button(renderer, theme, &chip, theme->row_active_mid, theme->panel_border);
    draw_text_clipped(renderer, fonts->medium, "C", &footer, chip.x + 11, chip.y + 1, footer_text);
    draw_text_clipped(renderer, fonts->small, "TITLE", &footer, chip.x + 42, chip.y - 1, footer_text);
}

static void draw_scanline_overlay(SDL_Renderer *renderer, int width, int height, const GuideTheme *theme) {
    (void) renderer;
    (void) width;
    (void) height;
    (void) theme;
}

void ui_render_no_media(SDL_Renderer *renderer, const UiCache *cache, int window_width, int window_height) {
    SDL_Rect full = {0, 0, window_width, window_height};
    fill_rect(renderer, &full, COLOR_NAVY_DARK);
    draw_cached_text(renderer, &cache->no_media_title, 58, 80);
    draw_cached_text(renderer, &cache->no_media_body, 58, 136);
    draw_cached_text(renderer, &cache->no_media_hint, 58, 176);
}

void ui_render_fullscreen(SDL_Renderer *renderer,
                          SDL_Texture *video_texture,
                          int texture_width,
                          int texture_height,
                          int window_width,
                          int window_height) {
    SDL_Rect window = {0, 0, window_width, window_height};
    fill_rect(renderer, &window, COLOR_BLACK);
    draw_video(renderer, video_texture, texture_width, texture_height, window);
}

void ui_render_guide(SDL_Renderer *renderer,
                     SDL_Texture *video_texture,
                     int texture_width,
                     int texture_height,
                     int window_width,
                     int window_height,
                     const GuideTheme *theme,
                     const UiFonts *fonts,
                     UiCache *cache,
                     const ChannelList *channels,
                     int active_channel,
                     Uint64 app_start_ticks,
                     Uint64 now_ticks,
                     time_t now_wall) {
    double scale_x = (double) window_width / WINDOW_WIDTH;
    double scale_y = (double) window_height / WINDOW_HEIGHT;
    int guide_x_start = (int) (GUIDE_X_START * scale_x);
    int sidebar_width = (int) (GUIDE_SIDEBAR_WIDTH * scale_x);
    SDL_Rect full = {0, 0, window_width, window_height};
    SDL_Rect info_panel = {0, 0, (int) (GUIDE_INFO_WIDTH * scale_x), (int) (GUIDE_INFO_HEIGHT * scale_y)};
    SDL_Rect preview = {window_width - (int) (GUIDE_PREVIEW_WIDTH * scale_x), 0, (int) (GUIDE_PREVIEW_WIDTH * scale_x), (int) (GUIDE_PREVIEW_HEIGHT * scale_y)};
    SDL_Rect status_bar = {info_panel.w, 0, window_width - info_panel.w, (int) (GUIDE_STATUS_HEIGHT * scale_y)};
    SDL_Rect header_row = {0, (int) ((GUIDE_GRID_TOP - GUIDE_STATUS_HEIGHT) * scale_y), window_width, (int) (GUIDE_STATUS_HEIGHT * scale_y)};
    SDL_Rect grid = {0, (int) (GUIDE_GRID_TOP * scale_y), window_width, window_height - (int) (GUIDE_GRID_TOP * scale_y) - (int) (GUIDE_FOOTER_HEIGHT * scale_y)};
    int row_height = grid.h / GUIDE_VISIBLE_ROWS;
    int timeline_w = window_width - guide_x_start - (int) (20 * scale_x);
    int start_index = active_channel - 2;
    const Channel *selected_channel = NULL;
    double pixels_per_minute = timeline_w / 90.0;

    if (channels && channels->count > 0 && active_channel >= 0 && active_channel < channels->count) {
        selected_channel = &channels->items[active_channel];
    }

    fill_three_stop_gradient(renderer,
                             &full,
                             theme->background_top,
                             theme->background_mid,
                             theme->background_bottom);
    draw_info_panel(renderer, fonts, theme, selected_channel, &info_panel, app_start_ticks, now_ticks, now_wall);
    draw_panel_shadow(renderer, &preview);
    fill_rect(renderer, &preview, COLOR_BLACK);
    draw_video(renderer, video_texture, texture_width, texture_height, preview);
    draw_status_bar(renderer, fonts->medium, theme, selected_channel, &status_bar, now_wall);

    if (cache->timeline_label_slot != now_wall / 60 || cache->timeline_theme != theme) {
        char label[32];
        for (int i = 0; i < 4; ++i) {
            format_clock_label(label, sizeof(label), now_wall, (int) ((TIMELINE_VISIBLE_SECONDS / 60.0 / 4) * i));
            text_texture_destroy(&cache->timeline_labels[i]);
            text_texture_init(&cache->timeline_labels[i], renderer, fonts->small, label, COLOR_TEXT_LIGHT);
        }
        cache->timeline_label_slot = now_wall / 60;
        cache->timeline_theme = theme;
    }
    draw_timeline_header_cached(renderer, cache, theme, header_row);
    draw_grid_background(renderer, theme, &grid, row_height, pixels_per_minute);

    if (start_index < 0) {
        start_index = 0;
    }
    if (channels && start_index + GUIDE_VISIBLE_ROWS > channels->count) {
        start_index = SDL_max(0, channels->count - GUIDE_VISIBLE_ROWS);
    }

    for (int row = 0; row < GUIDE_VISIBLE_ROWS; ++row) {
        int channel_index = start_index + row;
        SDL_Rect row_rect = {0, grid.y + row * row_height, window_width, row_height};
        SDL_Rect sidebar = {0, row_rect.y, sidebar_width, row_height};
        SDL_Rect timeline_rect = {guide_x_start, row_rect.y + (int) (6 * scale_y), timeline_w, row_height - (int) (12 * scale_y)};
        SDL_Rect clip = timeline_rect;
        int is_selected = channel_index == active_channel;
        SDL_Rect inset = {row_rect.x + 4, row_rect.y + 3, row_rect.w - 8, row_rect.h - 6};

        draw_beveled_bar(renderer,
                         &row_rect,
                         is_selected ? theme->row_active_top : theme->row_top,
                         is_selected ? theme->row_active_mid : theme->row_mid,
                         is_selected ? theme->row_active_bottom : theme->row_bottom,
                         theme->gloss,
                         theme->panel_border);
        fill_rect_alpha(renderer, &inset, (SDL_Color){255, 255, 255, is_selected ? 12 : 6});
        draw_beveled_bar(renderer,
                         &sidebar,
                         is_selected ? theme->row_active_top : theme->row_top,
                         is_selected ? theme->row_active_mid : theme->row_mid,
                         is_selected ? theme->row_active_bottom : theme->row_bottom,
                         theme->gloss,
                         theme->panel_border);

        if (!channels || channel_index >= channels->count) {
            continue;
        }

        {
            const Channel *channel = &channels->items[channel_index];
            double live_position = 0.0;
            double program_seek = 0.0;
            const ProgramEntry *program = channel_resolve_program(channel, app_start_ticks, now_ticks, &program_seek, NULL);
            time_t guide_view_start_time = now_wall - (30 * 60);
            time_t program_start_time = now_wall - (time_t) live_position;
            int block_x = guide_x_start;
            int block_w = 48;
            SDL_Rect block = {guide_x_start, timeline_rect.y + 4, 48, timeline_rect.h - 8};
            SDL_Rect title_rect = {block.x + 8, block.y + 8, block.w - 16, block.h - 16};
            char title[128];
            SDL_Color row_primary = ensure_contrast(is_selected ? theme->row_active_text : theme->row_text,
                                                    is_selected ? theme->row_active_mid : theme->row_mid);
            SDL_Color row_secondary = ensure_contrast(is_selected ? theme->row_active_subtext : theme->row_subtext,
                                                      is_selected ? theme->row_active_mid : theme->row_mid);
            SDL_Color block_text = ensure_contrast(is_selected ? theme->block_active_text : theme->block_text,
                                                   is_selected ? theme->block_active_mid : theme->block_mid);
            SDL_Color block_shadow = color_luma(is_selected ? theme->block_active_mid : theme->block_mid) < 120
                ? color_with_alpha(COLOR_BLACK, 255)
                : color_with_alpha(COLOR_TEXT_LIGHT, 255);

            if (!program) {
                continue;
            }
            live_position = channel_live_position_precise(channel, app_start_ticks, now_ticks);
            program_start_time = now_wall - (time_t) program_seek;
            block_x = guide_x_start + (int) (((double) (program_start_time - guide_view_start_time)) / 60.0 * pixels_per_minute);
            block_w = (int) ((program->duration_seconds / 60.0) * pixels_per_minute);
            block = (SDL_Rect){block_x, timeline_rect.y + 4, SDL_max(block_w, 48), timeline_rect.h - 8};
            title_rect = (SDL_Rect){block.x + 8, block.y + 8, block.w - 16, block.h - 16};

            if (is_selected) {
                draw_text_shadowed(renderer, fonts->medium, channel->name, &sidebar, 20, row_rect.y + 12, row_primary, color_with_alpha(COLOR_BLACK, 255));
                {
                    char number[16];
                    snprintf(number, sizeof(number), "%d", channel->number);
                    draw_text_shadowed(renderer, fonts->medium, number, &sidebar, 176, row_rect.y + 12, row_primary, color_with_alpha(COLOR_BLACK, 255));
                }
            } else {
                draw_text_shadowed(renderer, fonts->medium, channel->name, &sidebar, 20, row_rect.y + 12, row_primary, color_with_alpha(COLOR_BLACK, 255));
                {
                    char number[16];
                    snprintf(number, sizeof(number), "%d", channel->number);
                    draw_text_shadowed(renderer, fonts->medium, number, &sidebar, 176, row_rect.y + 12, row_primary, color_with_alpha(COLOR_BLACK, 255));
                }
            }
            draw_text_shadowed(renderer,
                               fonts->small,
                               program->file_name,
                               &sidebar,
                               20,
                               row_rect.y + 38,
                               row_secondary,
                               color_with_alpha(COLOR_BLACK, 255));

            SDL_RenderSetClipRect(renderer, &clip);
            draw_beveled_bar(renderer,
                             &block,
                             is_selected ? theme->block_active_top : theme->block_top,
                             is_selected ? theme->block_active_mid : theme->block_mid,
                             is_selected ? theme->block_active_bottom : theme->block_bottom,
                             is_selected ? theme->selection_edge : theme->gloss,
                             theme->panel_border);
            fit_text_with_ellipsis(is_selected ? fonts->medium : fonts->small,
                                   program->program_title,
                                   title_rect.w,
                                   title,
                                   sizeof(title));
            draw_text_shadowed(renderer,
                               is_selected ? fonts->medium : fonts->small,
                               title,
                               &title_rect,
                               title_rect.x,
                               title_rect.y,
                               block_text,
                               block_shadow);
            SDL_RenderSetClipRect(renderer, NULL);
        }
    }

    if (selected_channel && active_channel >= 0 && start_index <= active_channel && active_channel < start_index + GUIDE_VISIBLE_ROWS) {
        SDL_Rect highlight = {0, grid.y + (active_channel - start_index) * row_height, window_width, row_height};
        draw_selection_glow(renderer, &highlight, theme->selection_edge);
        draw_selection_glow(renderer, &(SDL_Rect){guide_x_start, highlight.y + (int) (6 * scale_y), timeline_w, row_height - (int) (12 * scale_y)}, theme->selection_edge);
    }

    draw_footer_legend(renderer, fonts, theme, window_width, window_height);
    draw_scanline_overlay(renderer, window_width, window_height, theme);
}

void ui_render_theme_picker(SDL_Renderer *renderer,
                            const UiFonts *fonts,
                            int window_width,
                            int window_height,
                            const GuideTheme *active_theme,
                            int current_theme_index,
                            int selected_theme_index) {
    SDL_Rect overlay = {0, 0, window_width, window_height};
    SDL_Rect modal = {window_width / 2 - 250, window_height / 2 - 180, 500, 360};
    SDL_Rect title_bar = {modal.x, modal.y, modal.w, 38};

    (void) current_theme_index;
    fill_rect_alpha(renderer, &overlay, (SDL_Color){0, 0, 0, 120});
    draw_panel_shadow(renderer, &modal);
    draw_rounded_top_panel(renderer, &modal, active_theme->panel_fill, active_theme->panel_border, active_theme->rounded_radius > 0 ? active_theme->rounded_radius : 8);
    fill_rect(renderer, &(SDL_Rect){modal.x, modal.y + 38, modal.w, modal.h - 38}, active_theme->footer_mid);
    draw_beveled_bar(renderer, &title_bar, active_theme->ribbon_top, active_theme->ribbon_mid, active_theme->ribbon_bottom, active_theme->gloss, active_theme->panel_border);
    draw_text_clipped(renderer, fonts->medium, "THEME SELECT", &modal, modal.x + 16, modal.y + 10, active_theme->ribbon_text);

    for (int i = 0; i < GUIDE_THEME_COUNT; ++i) {
        SDL_Rect item = {modal.x + 18, modal.y + 52 + i * 28, modal.w - 36, 24};
        SDL_Rect swatch = {modal.x + modal.w - 118, item.y + 4, 92, 14};
        char label[96];
        const GuideTheme *theme = &GUIDE_THEMES[i];

        if (i == selected_theme_index) {
            draw_beveled_bar(renderer, &item, theme->row_active_top, theme->row_active_mid, theme->row_active_bottom, theme->gloss, theme->panel_border);
            draw_selection_glow(renderer, &item, theme->selection_edge);
        }

        snprintf(label, sizeof(label), "%c %s", i == selected_theme_index ? '>' : ' ', theme->name);
        draw_text_clipped(renderer,
                          fonts->small,
                          label,
                          &item,
                          item.x + 8,
                          item.y + 4,
                          i == selected_theme_index ? theme->row_active_text : active_theme->panel_text);
        fill_three_stop_gradient(renderer, &swatch, theme->background_top, theme->background_mid, theme->background_bottom);
        stroke_rect(renderer, &swatch, theme->panel_border);
    }

    draw_text_clipped(renderer,
                      fonts->small,
                      "ENTER APPLY   ESC CANCEL   B CLOSE",
                      &modal,
                      modal.x + 18,
                      modal.y + modal.h - 28,
                      active_theme->panel_text);
}

int ui_cache_init(UiCache *cache, SDL_Renderer *renderer, const UiFonts *fonts, const ChannelList *channels) {
    char buffer[256];

    if (!cache || !renderer || !fonts) {
        return -1;
    }

    memset(cache, 0, sizeof(*cache));
    cache->renderer = renderer;
    cache->timeline_label_slot = -1;
    cache->timeline_labels = calloc(4, sizeof(UiTextTexture));
    if (!cache->timeline_labels) {
        ui_cache_destroy(cache);
        return -1;
    }

    if (text_texture_init(&cache->no_media_title, renderer, fonts->large, "Passport-C Media Player", COLOR_TEXT_LIGHT) != 0 ||
        text_texture_init(&cache->no_media_body, renderer, fonts->medium, "No channels found in ./media", COLOR_HIGHLIGHT_YELLOW) != 0 ||
        text_texture_init(&cache->no_media_hint, renderer, fonts->small, "Add MP4 or MKV files to ./media and relaunch.", COLOR_PALE_BLUE) != 0 ||
        text_texture_init(&cache->footer_a, renderer, fonts->medium, "A", COLOR_TEXT_DARK) != 0 ||
        text_texture_init(&cache->footer_time, renderer, fonts->small, "TIME", COLOR_TEXT_DARK) != 0 ||
        text_texture_init(&cache->footer_b, renderer, fonts->medium, "B", COLOR_TEXT_LIGHT) != 0 ||
        text_texture_init(&cache->footer_theme, renderer, fonts->small, "THEME", COLOR_TEXT_DARK) != 0 ||
        text_texture_init(&cache->footer_c, renderer, fonts->medium, "C", COLOR_TEXT_LIGHT) != 0 ||
        text_texture_init(&cache->footer_title, renderer, fonts->small, "TITLE", COLOR_TEXT_DARK) != 0) {
        ui_cache_destroy(cache);
        return -1;
    }

    if (channels && channels->count > 0) {
        cache->channels = calloc((size_t) channels->count, sizeof(UiChannelCache));
        if (!cache->channels) {
            ui_cache_destroy(cache);
            return -1;
        }
        cache->channel_count = channels->count;

        for (int i = 0; i < channels->count; ++i) {
            const Channel *channel = &channels->items[i];
            const ProgramEntry *program = channel->program_count > 0 ? &channel->programs[0] : NULL;
            snprintf(buffer, sizeof(buffer), "%d", channel->number);
            if (text_texture_init(&cache->channels[i].name_medium, renderer, fonts->medium, channel->name, COLOR_TEXT_LIGHT) != 0 ||
                text_texture_init(&cache->channels[i].number_medium, renderer, fonts->medium, buffer, COLOR_TEXT_LIGHT) != 0 ||
                text_texture_init(&cache->channels[i].file_small, renderer, fonts->small, program ? program->file_name : "", COLOR_PALE_BLUE) != 0 ||
                text_texture_init(&cache->channels[i].program_small_light, renderer, fonts->small, program ? program->program_title : "", COLOR_TEXT_LIGHT) != 0 ||
                text_texture_init(&cache->channels[i].program_medium_dark, renderer, fonts->medium, program ? program->program_title : "", COLOR_TEXT_DARK) != 0) {
                ui_cache_destroy(cache);
                return -1;
            }

            snprintf(buffer, sizeof(buffer), "%.0f min  -  %s", program ? program->duration_seconds / 60.0 : 0.0, program ? program->file_name : "");
            if (text_texture_init(&cache->channels[i].detail_small_dark, renderer, fonts->small, buffer, COLOR_TEXT_DARK) != 0) {
                ui_cache_destroy(cache);
                return -1;
            }
        }
    }

    return 0;
}

void ui_cache_destroy(UiCache *cache) {
    if (!cache) {
        return;
    }

    text_texture_destroy(&cache->no_media_title);
    text_texture_destroy(&cache->no_media_body);
    text_texture_destroy(&cache->no_media_hint);
    text_texture_destroy(&cache->footer_a);
    text_texture_destroy(&cache->footer_time);
    text_texture_destroy(&cache->footer_b);
    text_texture_destroy(&cache->footer_theme);
    text_texture_destroy(&cache->footer_c);
    text_texture_destroy(&cache->footer_title);

    if (cache->timeline_labels) {
        for (int i = 0; i < 4; ++i) {
            text_texture_destroy(&cache->timeline_labels[i]);
        }
        free(cache->timeline_labels);
    }

    if (cache->channels) {
        for (int i = 0; i < cache->channel_count; ++i) {
            text_texture_destroy(&cache->channels[i].name_medium);
            text_texture_destroy(&cache->channels[i].number_medium);
            text_texture_destroy(&cache->channels[i].file_small);
            text_texture_destroy(&cache->channels[i].program_small_light);
            text_texture_destroy(&cache->channels[i].program_medium_dark);
            text_texture_destroy(&cache->channels[i].detail_small_dark);
        }
        free(cache->channels);
    }

    memset(cache, 0, sizeof(*cache));
}

int ui_load_fonts(UiFonts *fonts) {
    if (!fonts) {
        return -1;
    }

    memset(fonts, 0, sizeof(*fonts));
    for (size_t i = 0; i < sizeof(FONT_CANDIDATES) / sizeof(FONT_CANDIDATES[0]); ++i) {
        fonts->small = TTF_OpenFont(FONT_CANDIDATES[i], 18);
        fonts->medium = TTF_OpenFont(FONT_CANDIDATES[i], 24);
        fonts->large = TTF_OpenFont(FONT_CANDIDATES[i], 32);
        if (fonts->small && fonts->medium && fonts->large) {
            return 0;
        }
        ui_destroy_fonts(fonts);
    }

    return -1;
}

void ui_destroy_fonts(UiFonts *fonts) {
    if (!fonts) {
        return;
    }

    if (fonts->small) {
        TTF_CloseFont(fonts->small);
    }
    if (fonts->medium) {
        TTF_CloseFont(fonts->medium);
    }
    if (fonts->large) {
        TTF_CloseFont(fonts->large);
    }
    memset(fonts, 0, sizeof(*fonts));
}