import cv2
import numpy as np
from PIL import Image, ImageDraw, ImageFont
import os


class ChineseTextRenderer:
    def __init__(self, font_path=None):
        self.font_cache = {}
        self.font_path = font_path

    def put_text(self, img, text, position, font_size=20, color=(0, 255, 0)):
        """安全的中文文本绘制函数"""
        # 输入验证
        if img is None:
            raise ValueError("输入图像不能为None")

        if not isinstance(img, np.ndarray):
            raise TypeError(f"输入图像必须是numpy数组，实际是{type(img)}")

        if len(img.shape) != 3 or img.shape[2] != 3:
            # 尝试转换
            if len(img.shape) == 2:
                img = cv2.cvtColor(img, cv2.COLOR_GRAY2BGR)
            elif len(img.shape) == 3 and img.shape[2] == 4:
                img = cv2.cvtColor(img, cv2.COLOR_BGRA2BGR)
            else:
                raise ValueError(f"不支持的图像格式，shape={img.shape}")

        try:
            # BGR转RGB
            img_rgb = cv2.cvtColor(img, cv2.COLOR_BGR2RGB)
            pil_img = Image.fromarray(img_rgb)
            draw = ImageDraw.Draw(pil_img)

            # 获取字体
            font = self._get_font(font_size)

            # 颜色转换：BGR到RGB
            rgb_color = color[::-1]

            # 绘制文本
            draw.text(position, text, font=font, fill=rgb_color)

            # RGB转BGR
            return cv2.cvtColor(np.array(pil_img), cv2.COLOR_RGB2BGR)

        except Exception as e:
            print(f"中文渲染失败: {e}，使用英文后备")
            # 后备方案：使用OpenCV绘制英文
            cv2.putText(img, text, position, cv2.FONT_HERSHEY_SIMPLEX,
                        font_size / 30, color, 2)
            return img

    def _get_font(self, size):
        """获取字体对象，带缓存"""
        if size in self.font_cache:
            return self.font_cache[size]

        # 查找字体文件
        font_paths = []
        if self.font_path and os.path.exists(self.font_path):
            font_paths.append(self.font_path)

        # 添加常用字体路径
        font_paths.extend([
            "simhei.ttf",
            "msyh.ttc",
            "C:/Windows/Fonts/simhei.ttf",
            "C:/Windows/Fonts/msyh.ttc",
            "C:/Windows/Fonts/Deng.ttf",
            "C:/Windows/Fonts/simsun.ttc",
        ])

        # 遍历所有可能的字体路径
        font = None
        for path in font_paths:
            if os.path.exists(path):
                try:
                    font = ImageFont.truetype(path, size, encoding="utf-8")
                    print(f"加载字体: {path}")
                    break
                except Exception as e:
                    continue

        # 如果找不到字体，尝试创建默认字体
        if font is None:
            try:
                font = ImageFont.load_default()
                # 调整默认字体大小
                font = ImageFont.truetype("arial.ttf", size)
            except:
                # 最后手段：使用PIL的默认字体
                font = ImageFont.load_default()

        self.font_cache[size] = font
        return font


def ensure_image_valid(img, default_size=(640, 480)):
    """确保图像有效，如果无效则创建默认图像"""
    if img is None or not isinstance(img, np.ndarray) or img.size == 0:
        print("创建默认图像...")
        img = np.zeros((default_size[0], default_size[1], 3), dtype=np.uint8)
        img.fill(50)
        # 添加一些参考线
        h, w = img.shape[:2]
        cv2.line(img, (0, 0), (w, h), (0, 255, 0), 1)
        cv2.line(img, (w, 0), (0, h), (0, 255, 0), 1)
        cv2.circle(img, (w // 2, h // 2), min(w, h) // 4, (255, 0, 0), 2)

    return img