import os
import PIL.Image as Image


class ImageProcessing:
    """
    图片加工类
    """

    def __init__(self, image_dir_path, image_size, image_row):
        self.image_dir_path = image_dir_path
        self.image_size = image_size
        self.image_row = image_row

    def merge_images(self):
        """
        合并图片
        @return: image_info_dict
        """

        # 获取图片集地址下的所有图片名称
        image_full_path_list = self.get_image_full_path_list(self.image_dir_path)
        image_full_path_list.sort()

        image_save_path = r'{}.jpg'.format(self.image_dir_path)  # 图片转换后的地址
        # 计算合成图片后的图片行数
        if len(image_full_path_list) % self.image_row == 0:
            image_row_num = len(image_full_path_list) // self.image_row
        else:
            image_row_num = len(image_full_path_list) // self.image_row + 1

        x_list = []
        y_list = []
        for img_file in image_full_path_list:
            img_x, img_y = self.get_new_img_xy(img_file, self.image_size)
            x_list.append(img_x)
            y_list.append(img_y)

        x_new = int(x_list[len(x_list) // 5 * 4])
        y_new = int(y_list[len(y_list) // 5 * 4])
        self.composite_images(self.image_row, self.image_size, image_row_num, image_full_path_list, image_save_path,
                              x_new, y_new)

        image_info_dict = {'width': x_list[0], 'height': sum(y_list), 'num': len(y_list)}
        return image_info_dict

    def get_image_full_path_list(self, image_dir_path):
        """
        获取图片完整路径列表
        @param image_dir_path: 图片路径
        @return: image_full_path_list
        """
        file_name_list = os.listdir(image_dir_path)
        image_full_path_list = []
        for file_name_one in file_name_list:
            file_one_path = os.path.join(image_dir_path, file_name_one)
            if os.path.isfile(file_one_path):
                image_full_path_list.append(file_one_path)
            else:
                img_path_list = self.get_image_full_path_list(file_one_path)
                image_full_path_list.extend(img_path_list)
        return image_full_path_list

    @staticmethod
    def get_new_img_xy(img_file, image_size):
        """
        获取图片宽高像素
        @param img_file: 图片文件
        @param image_size: 图片大小
        @return : x_s(宽像素), y_s(高像素)
        """
        im = Image.open(img_file)
        if image_size == 0:     # 等于0时按照原比例
            (x_s, y_s) = im.size
            return x_s, y_s
        else:
            (x, y) = im.size
            lv = round(x / image_size, 2) + 0.01
            x_s = x // lv
            y_s = y // lv
            return x_s, y_s

    def composite_images(self, image_row, image_size, image_row_num, image_names, image_save_path, x_new, y_new):
        """
        合成图片
        @param image_row: 图片行数(合成前)
        @param image_size: 图片大小
        @param image_row_num: 图片行数(合成后)
        @param image_names: 图片名字
        @param image_save_path: 图片保存路径
        @param x_new: 横向位置
        @param y_new: 纵向位置
        @return: None
        """
        to_image = Image.new('RGB', (image_row * x_new, image_row_num * y_new))  # 创建一个新图
        # 循环遍历，把每张图片按顺序粘贴到对应位置上
        total_num = 0
        for y in range(1, image_row_num + 1):
            for x in range(1, image_row + 1):
                from_image = self.resize_by_width(image_names[image_row * (y - 1) + x - 1], image_size)
                to_image.paste(from_image, ((x - 1) * x_new, (y - 1) * y_new))
                total_num += 1
                if total_num == len(image_names):
                    break
        to_image.save(image_save_path)  # 保存新图

    @staticmethod
    def resize_by_width(infile, image_size):
        """按照宽度进行所需比例缩放"""
        im = Image.open(infile)
        if image_size != 0:
            (x, y) = im.size
            lv = round(x / image_size, 2) + 0.01
            x_s = int(x // lv)
            y_s = int(y // lv)
            print("x_s", x_s, y_s)
            out = im.resize((x_s, y_s), Image.ANTIALIAS)
            return out
        else:
            (x_s, y_s) = im.size
            print("x_s", x_s, y_s)
            out = im.resize((x_s, y_s), Image.ANTIALIAS)
            return out