# Author: fruit.com.cn
"""使用确认的 ymb 原图生成图标、启动标识及原生平台尺寸。"""

import json
from pathlib import Path

from PIL import Image, ImageChops, ImageDraw

ROOT = Path(__file__).resolve().parents[1]
ASSETS = ROOT / "assets/icon"
IOS = ROOT / "ios/Runner/Assets.xcassets"
ANDROID = ROOT / "android/app/src/main/res"
REFERENCE = ROOT / "assets/branding/ymb-reference.png"
LAUNCH_REFERENCE = ROOT / "assets/branding/ymb-launch-reference.png"
BRAND_RED = "#E9142E"
WHITE = "#FFFFFF"
CLEAR = (0, 0, 0, 0)
MASTER_SIZE = 1024
SPLASH_SIZE = 80
SPLASH_RADIUS = 18
ANDROID12_SIZE = 288
FOREGROUND_SIZE = 108
LEGACY_SIZE = 48
PLACEHOLDER_SIZE = (600, 360)
LAUNCH_SIZE = (390, 844)
WHITE_THRESHOLD = 100
WHITE_RANGE = 145
DENSITIES = {"mdpi": 1, "hdpi": 1.5, "xhdpi": 2, "xxhdpi": 3, "xxxhdpi": 4}
RESAMPLE = Image.Resampling.LANCZOS


def wordmark(reference):
    """从原图白色字标提取透明前景，不重新绘制或改变字形。"""
    channels = reference.convert("RGB").split()
    lightness = ImageChops.darker(ImageChops.darker(*channels[:2]), channels[2])
    alpha = lightness.point(
        lambda value: max(0, min(255, round(
            (value - WHITE_THRESHOLD) * 255 / WHITE_RANGE
        )))
    )
    image = Image.new("RGBA", reference.size, WHITE)
    image.putalpha(alpha)
    return image


def centered(canvas, mark):
    """将标识按可见边界居中，不包含字体基线额外留白。"""
    origin = ((canvas.width - mark.width) // 2, (canvas.height - mark.height) // 2)
    canvas.alpha_composite(mark, origin)
    return canvas


def scaled_wordmark(mark, width):
    """等比缩放字标，所有输出共用同一字形。"""
    height = round(mark.height * width / mark.width)
    return mark.resize((width, height), RESAMPLE)


def splash_icon(master, size):
    """仅启动图烘焙圆角；桌面图标保留系统负责的裁切。"""
    image = master.resize((size, size), RESAMPLE).convert("RGBA")
    mask = Image.new("L", (MASTER_SIZE, MASTER_SIZE))
    radius = MASTER_SIZE * SPLASH_RADIUS / SPLASH_SIZE
    ImageDraw.Draw(mask).rounded_rectangle(
        (0, 0, MASTER_SIZE - 1, MASTER_SIZE - 1), radius=radius, fill=255
    )
    image.putalpha(mask.resize((size, size), RESAMPLE))
    return image


def save(image, target):
    """写入明确路径的生成资源，不清理或删除目录。"""
    target.parent.mkdir(parents=True, exist_ok=True)
    image.save(target, optimize=True)


def ios_assets(master):
    """严格按资源目录声明导出图标；开屏保留确认的完整参考图。"""
    app_icons = IOS / "AppIcon.appiconset"
    manifest = json.loads((app_icons / "Contents.json").read_text())
    for entry in manifest["images"]:
        points = float(entry["size"].split("x")[0])
        scale = int(entry["scale"].removesuffix("x"))
        pixels = round(points * scale)
        save(master.resize((pixels, pixels), RESAMPLE), app_icons / entry["filename"])
    for scale in (1, 2, 3):
        suffix = "" if scale == 1 else f"@{scale}x"
        size = tuple(value * scale for value in LAUNCH_SIZE)
        image = Image.open(LAUNCH_REFERENCE).convert("RGB").resize(size, RESAMPLE)
        save(image, IOS / f"LaunchImage.imageset/LaunchImage{suffix}.png")


def android_assets(master, foreground):
    """覆盖现有密度资源，并为 Android 12 提供独立安全区标识。"""
    for density, scale in DENSITIES.items():
        pixels = round(LEGACY_SIZE * scale)
        save(
            master.resize((pixels, pixels), RESAMPLE),
            ANDROID / f"mipmap-{density}/ic_launcher.png",
        )
        pixels = round(FOREGROUND_SIZE * scale)
        save(
            foreground.resize((pixels, pixels), RESAMPLE),
            ANDROID / f"drawable-{density}/ic_launcher_foreground.png",
        )
        save(
            Image.new("RGB", (pixels, pixels), BRAND_RED),
            ANDROID / f"mipmap-{density}/ic_launcher_background.png",
        )
        mark = splash_icon(master, round(SPLASH_SIZE * scale))
        save(mark, ANDROID / f"drawable-{density}/splash_screen.png")
        size = round(ANDROID12_SIZE * scale)
        image = centered(Image.new("RGBA", (size, size), CLEAR), mark)
        save(image, ANDROID / f"drawable-{density}/android12splash.png")


def main():
    """直接复用确认的原始图标和开屏，输出平台所需尺寸。"""
    reference = Image.open(REFERENCE).convert("RGB")
    master = reference.resize((MASTER_SIZE, MASTER_SIZE), RESAMPLE)
    mark = wordmark(reference)
    foreground = mark.resize((MASTER_SIZE, MASTER_SIZE), RESAMPLE)
    save(master, ASSETS / "ymb.png")
    save(foreground, ASSETS / "ymb_foreground.png")
    placeholder = centered(
        Image.new("RGBA", PLACEHOLDER_SIZE, CLEAR),
        scaled_wordmark(mark.crop(mark.getbbox()), PLACEHOLDER_SIZE[0]),
    )
    save(placeholder, ASSETS / "splash_logo.png")
    icon = splash_icon(master, SPLASH_SIZE * 4)
    size = ANDROID12_SIZE * 4
    save(
        centered(Image.new("RGBA", (size, size), CLEAR), icon),
        ASSETS / "ymb_android12.png",
    )
    ios_assets(master)
    android_assets(master, foreground)
    print("Generated ymb assets: master 1024, iOS catalog, Android 5 densities.")


if __name__ == "__main__":
    main()