"""web/radio 封面：1080x1920，深夜电台主题——深蓝夜色底、红灯「ON AIR」、
声波弧线与竖排标题《不眠频率》。可复现脚本（固定 seed，无外部网络依赖）。

用法：python3 web/radio/gen/gen_cover.py
      （或 .venv-tts/bin/python web/radio/gen/gen_cover.py）
"""
import math
import os
import random

from PIL import Image, ImageDraw, ImageFilter, ImageFont

W, H = 1080, 1920
FONT_CANDIDATES = [
    "/home/xsl/SoundGame/web/rhythm/gen/NotoSansSC-Bold.ttf",
    "/home/xsl/SoundGame/app/src/reflex/gen/NotoSansSC-Bold.ttf",
]
OUT = os.path.join(os.path.dirname(os.path.abspath(__file__)), "..", "cover.png")


def load_font(size):
    for p in FONT_CANDIDATES:
        if os.path.exists(p):
            return ImageFont.truetype(p, size)
    raise SystemExit("未找到中文字体，请放一份 NotoSansSC-Bold.ttf 到 web/rhythm/gen/")


def main():
    rng = random.Random(915)  # 固定 seed：可复现
    img = Image.new("RGB", (W, H), (8, 10, 24))
    d = ImageDraw.Draw(img)

    # 背景竖向微渐变：深夜蓝 → 微亮天际（黎明前的电台夜班）
    for y in range(H):
        t = y / H
        d.line([(0, y), (W, y)],
               fill=(int(8 + 10 * t), int(10 + 12 * t), int(24 + 26 * t)))

    # 远景声波弧线（电台频率的具象，模糊压暗做背景）
    wave = Image.new("RGBA", (W, H), (0, 0, 0, 0))
    wd = ImageDraw.Draw(wave)
    palette = [(94, 234, 212), (129, 140, 248), (244, 114, 182)]
    for i in range(22):
        cx, cy = rng.randint(0, W), rng.randint(0, H)
        r = rng.randint(80, 360)
        col = palette[i % len(palette)]
        wd.ellipse([cx - r, cy - r, cx + r, cy + r],
                   outline=col + (rng.randint(8, 26),), width=rng.randint(2, 4))
    wave = wave.filter(ImageFilter.GaussianBlur(1.6))
    img.paste(wave, (0, 0), wave)
    d = ImageDraw.Draw(img)

    # 中央：红色「ON AIR」指示灯 + 同心圆话筒波纹
    cx, cy = W // 2, 620
    for i, (r, alpha) in enumerate([(300, 46), (224, 78), (152, 118)]):
        ring = Image.new("RGBA", (W, H), (0, 0, 0, 0))
        rd = ImageDraw.Draw(ring)
        rd.ellipse([cx - r, cy - r, cx + r, cy + r],
                   outline=(248, 113, 113, alpha), width=8 - i * 2)
        img.paste(ring, (0, 0), ring)
    d = ImageDraw.Draw(img)
    d.ellipse([cx - 64, cy - 64, cx + 64, cy + 64], fill=(220, 38, 38))
    d.ellipse([cx - 30, cy - 30, cx + 30, cy + 30], fill=(252, 165, 165))
    f_lamp = load_font(52)
    bbox = d.textbbox((0, 0), "ON AIR", font=f_lamp)
    d.text((cx - (bbox[2] - bbox[0]) / 2 - bbox[0], cy - (bbox[3] - bbox[1]) / 2 - bbox[1] - 210),
           "ON AIR", font=f_lamp, fill=(248, 113, 113))

    # 标题（居中）与副题
    f_title = load_font(168)
    f_sub = load_font(54)
    f_small = load_font(38)

    def ctext(y, s, font, fill, spacing=8):
        bbox = d.textbbox((0, 0), s, font=font)
        w = bbox[2] - bbox[0]
        x = (W - w) / 2
        for ch in s:
            d.text((x, y), ch, font=font, fill=fill)
            bb = d.textbbox((0, 0), ch, font=font)
            x += (bb[2] - bb[0]) + spacing

    ctext(1020, "不眠频率", f_title, (240, 244, 255), spacing=14)
    ctext(1260, "深夜电台热线 · 接住五个陌生人的夜晚", f_sub, (148, 163, 184))

    # 手势图例（极简两行）
    hints = ["单击 接听 / 跳句", "左右滑 抉择", "上滑 状态", "下滑 菜单", "双击 重听"]
    for i, s in enumerate(hints):
        col, row = i % 3, i // 3
        d.text((110 + col * 300, 1420 + row * 76), s, font=f_small, fill=(110, 130, 160))

    ctext(1700, "午夜零点，热线灯亮。你说什么，由你决定。", f_small, (90, 105, 135))

    img.save(OUT)
    print(OUT, img.size)


if __name__ == "__main__":
    main()