"""
滑块验证码数据生成器

生成滑块验证码训练数据：随机纹理/色块背景 + 方形缺口 + 阴影效果。
标签 = 缺口中心 x 坐标 (整数)
文件名格式: {gap_center_x}_{index:06d}.png
"""

import random

from PIL import Image, ImageDraw, ImageFilter

from config import SOLVER_CONFIG
from generators.base import BaseCaptchaGenerator


class SlideDataGenerator(BaseCaptchaGenerator):
    """滑块验证码数据生成器。"""

    def __init__(self, seed: int | None = None):
        from config import RANDOM_SEED
        super().__init__(seed=seed if seed is not None else RANDOM_SEED)

        self.cfg = SOLVER_CONFIG["slide"]
        self.height, self.width = self.cfg["cnn_input_size"]  # (H, W)
        self.gap_size = 40  # 缺口大小

    def generate(self, text: str | None = None) -> tuple[Image.Image, str]:
        rng = self.rng
        gs = self.gap_size

        # 缺口左边界 x 范围: 留出边距，标签统一使用缺口中心 x
        margin = gs + 10
        gap_left = rng.randint(margin, self.width - margin)
        gap_y = rng.randint(10, self.height - gs - 10)
        gap_center_x = gap_left + gs // 2

        if text is None:
            text = str(gap_center_x)

        # 1. 生成纹理背景
        img = self._textured_background(rng)

        # 2. 绘制缺口 (半透明灰色区域 + 阴影)
        overlay = Image.new("RGBA", img.size, (0, 0, 0, 0))
        overlay_draw = ImageDraw.Draw(overlay)

        # 阴影 (稍大一圈)
        overlay_draw.rectangle(
            [gap_left + 2, gap_y + 2, gap_left + gs + 2, gap_y + gs + 2],
            fill=(0, 0, 0, 60),
        )
        # 缺口本体
        overlay_draw.rectangle(
            [gap_left, gap_y, gap_left + gs, gap_y + gs],
            fill=(80, 80, 80, 160),
            outline=(60, 60, 60, 200),
            width=2,
        )

        img = img.convert("RGBA")
        img = Image.alpha_composite(img, overlay)
        img = img.convert("RGB")

        # 3. 轻微模糊
        img = img.filter(ImageFilter.GaussianBlur(radius=0.3))

        return img, text

    def _textured_background(self, rng: random.Random) -> Image.Image:
        """生成带纹理的彩色背景。"""
        img = Image.new("RGB", (self.width, self.height))
        draw = ImageDraw.Draw(img)

        # 渐变底色
        base_r = rng.randint(80, 200)
        base_g = rng.randint(80, 200)
        base_b = rng.randint(80, 200)
        for y in range(self.height):
            ratio = y / max(self.height - 1, 1)
            r = int(base_r + 40 * ratio)
            g = int(base_g - 20 * ratio)
            b = int(base_b + 20 * ratio)
            r, g, b = max(0, min(255, r)), max(0, min(255, g)), max(0, min(255, b))
            draw.line([(0, y), (self.width, y)], fill=(r, g, b))

        # 纹理噪声
        for _ in range(self.width * self.height // 6):
            x = rng.randint(0, self.width - 1)
            y = rng.randint(0, self.height - 1)
            pixel = img.getpixel((x, y))
            noise = tuple(
                max(0, min(255, c + rng.randint(-30, 30)))
                for c in pixel
            )
            draw.point((x, y), fill=noise)

        # 随机色块 (模拟图案)
        for _ in range(rng.randint(4, 8)):
            x1, y1 = rng.randint(0, self.width - 30), rng.randint(0, self.height - 20)
            x2, y2 = x1 + rng.randint(15, 50), y1 + rng.randint(10, 30)
            color = tuple(rng.randint(50, 230) for _ in range(3))
            draw.rectangle([x1, y1, x2, y2], fill=color)

        # 随机圆形
        for _ in range(rng.randint(2, 5)):
            cx = rng.randint(10, self.width - 10)
            cy = rng.randint(10, self.height - 10)
            cr = rng.randint(5, 20)
            color = tuple(rng.randint(50, 230) for _ in range(3))
            draw.ellipse([cx - cr, cy - cr, cx + cr, cy + cr], fill=color)

        return img