#!/usr/bin/env python3
"""Generate recolored outfit textures for Kira's Live2D model.

Takes the base texture_02.png (clothing layer) and creates
color variants for each outfit using HSL shifts on non-skin areas.
"""

from PIL import Image
import colorsys
import os

BASE_DIR = os.path.expanduser(
    "~/Projects/ai-body-double/frontend/public/live2d/models/kira"
)
TEXTURE_DIR = os.path.join(BASE_DIR, "Epsilon.1024")
OUT_DIR = os.path.join(BASE_DIR, "outfits")

# Outfit → HSL shift mapping (hue_shift_deg, sat_mult, light_mult)
# Applied to non-white, non-skin pixels
OUTFITS = {
    "cozy-hoodie":   (10,   1.1, 1.0),   # warm pink shift
    "girly-dress":   (240,  1.2, 0.95),  # lavender/purple
    "pajama-set":    (140,  0.8, 1.1),   # minty green
    "study-sweater": (30,   1.1, 1.0),   # warm orange/amber
    "going-out":     (320,  1.3, 1.05),  # bright pink/magenta
}

def is_skin(r, g, b):
    """Roughly detect skin tones (avoid recoloring skin)."""
    return 180 < r < 250 and 120 < g < 200 and 80 < b < 170

def is_white_or_void(r, g, b, a):
    """Detect transparent or near-white pixels."""
    if a < 10:
        return True
    return r > 240 and g > 240 and b > 240

def recolor_texture(src_path, dst_path, hue_shift, sat_mult, light_mult):
    """Recolor a texture by shifting HSL on non-skin, non-white pixels."""
    img = Image.open(src_path).convert("RGBA")
    pixels = img.load()
    w, h = img.size

    for y in range(h):
        for x in range(w):
            r, g, b, a = pixels[x, y]
            if is_white_or_void(r, g, b, a) or is_skin(r, g, b):
                continue

            # Convert to HSL
            h_val, l_val, s_val = colorsys.rgb_to_hls(r / 255, g / 255, b / 255)

            # Apply shifts
            h_val = (h_val + hue_shift / 360) % 1.0
            s_val = min(1.0, s_val * sat_mult)
            l_val = max(0, min(1.0, l_val * light_mult))

            # Convert back to RGB
            nr, ng, nb = colorsys.hls_to_rgb(h_val, l_val, s_val)
            pixels[x, y] = (int(nr * 255), int(ng * 255), int(nb * 255), a)

    os.makedirs(os.path.dirname(dst_path), exist_ok=True)
    img.save(dst_path)
    size = os.path.getsize(dst_path)
    print(f"  Created {os.path.basename(dst_path)} ({size//1024}KB)")


def main():
    src = os.path.join(TEXTURE_DIR, "texture_02.png")
    if not os.path.exists(src):
        print(f"Source not found: {src}")
        return 1

    print(f"Generating outfit textures from {src}")
    print()

    for outfit_name, (hue, sat, light) in OUTFITS.items():
        dst = os.path.join(OUT_DIR, f"{outfit_name}.png")
        print(f"  {outfit_name}: hue={hue}° sat={sat:.1f}x light={light:.2f}x")
        recolor_texture(src, dst, hue, sat, light)

    print()
    print("Done! Texture variants ready.")
    return 0


if __name__ == "__main__":
    exit(main())