from PIL import Image, ImageDraw, ImageFile, ImageFont
from typing import Union, Type

class PicItem:
    def __init__(self, pic, label: str):
        self.pic = Image.open(pic) if isinstance(pic, str) else pic
        self.label = label

class PictureMatrixGenerater():
    def __init__(self, background: str, picSize: tuple, itemSize: tuple, margin: int, itemNum: int, fontMargin: int, font: str, fontSize: int):
        self.backImage = Image.open(background)
        self.picSize = picSize
        self.itemSize = itemSize
        self.margin = margin
        self.itemNum = itemNum
        self.fontSize = fontSize
        self.fontMargin = fontMargin
        self.actualSize = (itemSize[0], itemSize[1] + fontMargin + int(fontSize * 1.5))
        self.font = ImageFont.truetype(font, fontSize)  

    def cutPic(self, img: ImageFile) -> Image:
        # 等比放小50%
        img = img.resize((int(img.width * 0.5), int(img.height * 0.5)))
        left = (img.width - self.itemSize[0])/2 
        top = (img.height - self.itemSize[1])/2
        right = (img.width + self.itemSize[0])/2
        bottom = (img.height + self.itemSize[1])/2
        return img.crop((left, top, right, bottom))


    def drawComponent(self, pic: ImageFile, text: str, startX: int = 0, startY: int = 0) -> Image:
        components = Image.new('RGBA', self.actualSize, color=(0, 0, 0, 0))
        components.paste(self.cutPic(pic), (0, 0))
        draw = ImageDraw.Draw(components)
        text_bbox = draw.textbbox((0, 0), text, font=self.font)
        # 计算文本宽度（文本框实际宽度）
        text_width = text_bbox[2] - text_bbox[0]
        # 计算文本居中
        item_center_x = (startX + (self.itemSize[0] / 2))
        text_y = startY + self.itemSize[1] + self.fontMargin
        draw.text((item_center_x - (text_width / 2), text_y), text, fill=(255, 255, 255), font=self.font)
        return components

    def generate(self, picList: list[PicItem]) -> Image:
        backImage = Image.new('RGB', self.picSize, color=(255, 255, 255))
        backImage.paste(self.backImage, (0, 0))

        num: int = len(picList)
        # 计算某行的实际宽度
        vSize = num * (self.actualSize[0] + num - 1) if num <= 5 else 5 * (self.actualSize[0] + num - 1)
        # 计算左右边距以确保当前行居中展示
        mSize = (self.picSize[0] - vSize) / 2 - self.margin * 2
        # 如果只有一行，则计算居中，如果两行，则设置为200
        marginTop = int(self.picSize[1] / 2) - int(self.itemSize[1] / 2) if num <= 5 else 200
        nextYStart = marginTop + self.actualSize[1] + 50 if num > 5 else -1
        nextViewSize = (num % 5) * (self.itemSize[0] + num - 1) if num < 10 else 5 * (self.itemSize[0] + num - 1)
        nextMarginSize = (self.picSize[0] - nextViewSize) / 2 - self.margin * 2

        for idx, img in enumerate(picList):
            calc_X = int((self.itemSize[0] + self.margin) * idx + mSize) if idx < 5 else int((self.itemSize[0] + self.margin) * (idx % 5) + nextMarginSize)
            calc_Y = marginTop if idx < 5 else nextYStart
            # print((calc_X, calc_Y))
            component = self.drawComponent(img.pic, img.label, 0, 0)
            backImage.paste(component, (calc_X, calc_Y), mask=component)
        return backImage

    def config(self, picSize: tuple, itemSize: tuple, margin: int, itemNum: int, fontMargin: int, font: str, fontSize: int):
        self.picSize = picSize
        self.itemSize = itemSize
        self.margin = margin
        self.itemNum = itemNum
        self.fontSize = fontSize
        self.fontMargin = fontMargin
        self.actualSize = (itemSize[0], itemSize[1] + fontMargin + int(fontSize * 1.5))
        self.font = ImageFont.truetype(font, fontSize)