import os
import random
from PIL import Image

def is_image_file(file_path):
    valid_extensions = (".png", ".jpg", ".jpeg", ".gif", ".bmp")  # 可识别的图片格式
    _, extension = os.path.splitext(file_path)
    return extension.lower() in valid_extensions

def overlay_images(background_folder, overlay_folder, output_folder):
    # 获取背景图片列表
    background_files = [file for file in os.listdir(background_folder) if is_image_file(file)]
    overlay_files = [file for file in os.listdir(overlay_folder) if is_image_file(file)]

    # 确保输出文件夹存在
    if not os.path.exists(output_folder):
        os.makedirs(output_folder)

    # 循环遍历每个背景图片
    for bg_file in background_files:
        bg_path = os.path.join(background_folder, bg_file)
        background = Image.open(bg_path).convert("RGBA")

        # 获取背景图片的宽高
        bg_width, bg_height = background.size
        min_dimension = min(bg_width, bg_height)
        new_size = (min_dimension // 2, min_dimension // 2)

        # 循环遍历每个透明背景图片，并依次进行合成
        for overlay_file in overlay_files:
            overlay_path = os.path.join(overlay_folder, overlay_file)
            overlay = Image.open(overlay_path).convert("RGBA")

            # 调整透明背景图片的大小
            overlay.thumbnail(new_size, Image.LANCZOS)

            # 随机生成合成图片的位置，确保不超出背景图片边界
            max_x = bg_width - overlay.width
            max_y = bg_height - overlay.height
            position = (random.randint(0, max_x), random.randint(0, max_y))

            # 创建新的背景图，并将透明背景图片按照透明度融合上去
            merged_image = background.copy()
            merged_image.alpha_composite(overlay, dest=position)

            # 将合成后的图片调整到背景图片的一半大小
            merged_image.thumbnail(new_size, Image.LANCZOS)

            # 保存合成图片
            output_path = os.path.join(output_folder, f"merged_{bg_file}_{overlay_file}")
            merged_image.save(output_path, "PNG")

if __name__ == "__main__":
    # 输入文件夹路径
    background_folder = "/Users/zhenzhipeng/development/数据集相关文件/背景"
    overlay_folder = "/Users/zhenzhipeng/Library/Containers/com.tencent.xinWeChat/Data/Library/Application Support/com.tencent.xinWeChat/2.0b4.0.9/abb33b2d6c9d8decd9ef7c0ddebe8cc2/Message/MessageTemp/050dd051d428f6b6f4a308cc5b7bef67/File/data/blue_plate"
    output_folder = "/Users/zhenzhipeng/development/数据集相关文件/chepai"

    overlay_images(background_folder, overlay_folder, output_folder)