"""Reference compositor for player sprites (the C++ client mirrors this in client/CharacterSprite.cpp).

look = {"body": "male", "skin": 0..5, "items": {slot: item_id or None}, "colors": {slot: "#rrggbb"}}
"""
from pathlib import Path

import numpy as np
from PIL import Image

ROOT = Path(__file__).resolve().parent.parent
CHAR_DIR = ROOT / "assets" / "characters"


def hex_rgb(h):
    h = h.lstrip("#")
    return tuple(int(h[i:i + 2], 16) for i in (0, 2, 4))


def ramp(hex_color, shades=4):
    """Shade 1 (darkest) .. 4 (highlight) for one base color. Must match colorRamp() in
    client/CharacterSprite.cpp. Multiplicative per channel (cool, slightly saturated shadows,
    warm highlights), so white, black and very light colors all shade sensibly."""
    c = hex_rgb(hex_color)
    table = [(0.50, (0.96, 0.90, 1.06)), (0.73, (0.99, 0.95, 1.03)), (1.0, (1.0, 1.0, 1.0))]
    out = []
    for k, tint in table:
        out.append(tuple(max(0, min(255, round(ch * k * t))) for ch, t in zip(c, tint)))
    warm = (255, 250, 232)
    out.append(tuple(round(ch + (w - ch) * 0.34) for ch, w in zip(c, warm)))
    return out[:shades]


def _layer(path):
    return np.asarray(Image.open(path).convert("RGBA"))


def _paint_shade(canvas, shade, color, shades):
    lv = (shade[..., 0].astype(int) + 30) // 60
    m = shade[..., 3] > 127
    pal = ramp(color, shades)
    for i in range(1, shades + 1):
        sel = m & (lv == i)
        canvas[sel, :3] = pal[i - 1]
        canvas[sel, 3] = 255


def _paint_fixed(canvas, fixed):
    m = fixed[..., 3] > 127
    canvas[m] = fixed[m]


def compose_sheet(manifest, look):
    body = look["body"]
    d = CHAR_DIR / body
    shades = manifest["shades"]
    items = manifest["items"]
    chosen = look.get("items", {})
    colors = look.get("colors", {})
    body_img = _layer(d / "body.png")
    canvas = np.zeros_like(body_img)
    _paint_shade(canvas, _layer(d / "skin_shade.png"), manifest["skinTones"][look.get("skin", 0)], shades)
    for base_item, slot in (("top_tee", "top"), ("bottom_shorts", "bottom")):
        color = colors.get(slot) if chosen.get(slot) == base_item else None
        _paint_shade(canvas, _layer(d / f"{base_item}_shade.png"), color or items[base_item]["color"], shades)
    _paint_fixed(canvas, body_img)
    for slot, _z in sorted(manifest["slots"].items(), key=lambda kv: kv[1]):
        item_id = chosen.get(slot)
        if not item_id or items.get(item_id, {}).get("fromBody"):
            continue
        _paint_shade(canvas, _layer(d / f"{item_id}_shade.png"), colors.get(slot) or items[item_id]["color"], shades)
        _paint_fixed(canvas, _layer(d / f"{item_id}.png"))
    return Image.fromarray(canvas)