from __future__ import annotations

from pathlib import Path

from PIL import Image, ImageDraw, ImageFont

from engine.render.ui_draw import GLYPH_SIZE, PRINTABLE_MAX, PRINTABLE_MIN, glyph_texture_path, panel_texture_path

FONT_PIXEL_SIZE = 13

# Flat RGBA fills for menu chrome - deliberately plain (unlike world tiles/items' checker
# placeholder texture) so text stays legible on top of them. See engine/placeholder_textures.py
# for the equivalent generator for world-space art.
UI_PANEL_COLORS: dict[str, tuple[int, int, int, int]] = {
    "background": (12, 14, 20, 235),
    "highlight": (70, 110, 200, 235),
    "border": (150, 160, 180, 255),
    "accent": (200, 90, 40, 235),
}

_font_cache = None


def _font():
    global _font_cache
    if _font_cache is None:
        _font_cache = ImageFont.load_default(size=FONT_PIXEL_SIZE)
    return _font_cache


def generate_ui_textures(textures_dir: Path) -> None:
    """Writes one glyph PNG per printable ASCII character plus a handful of flat-color panel
    fills, if missing. Same on-demand approach as generate_placeholder_textures, just for menu
    chrome (start screen, controls menu, character card) instead of world tile/item art.
    """
    size = int(GLYPH_SIZE)
    for code in range(PRINTABLE_MIN, PRINTABLE_MAX + 1):
        ch = chr(code)
        path = textures_dir / glyph_texture_path(ch)
        if path.exists():
            continue
        path.parent.mkdir(parents=True, exist_ok=True)
        img = Image.new("RGBA", (size, size), (0, 0, 0, 0))
        ImageDraw.Draw(img).text((1, 0), ch, font=_font(), fill=(255, 255, 255, 255))
        img.save(path)

    for name, color in UI_PANEL_COLORS.items():
        path = textures_dir / panel_texture_path(name)
        if path.exists():
            continue
        path.parent.mkdir(parents=True, exist_ok=True)
        Image.new("RGBA", (8, 8), color).save(path)