feat: 商品主图背景功能

package.json

@@ -9,8 +9,9 @@
         "ppt": "node ./src/ppt_to_img.js",
         "merge": "node ./src/img_merge.js",
         "water": "node ./src/water_market.js",
-        "pptToImg": "npm run ppt && npm run merge && npm run water && npm run cover",
-        "pyToImg": "npm run merge && npm run water && npm run cover"
+        "bg": "node ./src/product_main_img_bg.js",
+        "pptToImg": "npm run ppt && npm run merge && npm run water && npm run cover && npm run bg",
+        "pyToImg": "npm run merge && npm run water && npm run cover && npm run bg"
     },
     "author": "",
     "license": "ISC",

src/product_main_img_bg.js

@@ -0,0 +1,74 @@
+const sharp = require('sharp');
+const fs = require('fs');
+const path = require('path');
+const { getInputDir } = require('../utils/index');
+const { cover } = require('../config/index');
+
+//工作目录文件夹路径
+let inputDir = getInputDir();
+const scaleDir = `${inputDir}/1x1`;
+if (!inputDir || !scaleDir) {
+    console.log('未执行拼接商品主图背景功能，工作目录不存在');
+    return;
+}
+
+async function mergeMainImgBg(folderPath, row = 2) {
+    const images = fs.readdirSync(folderPath);
+    const imagePaths = images
+        .map((image) => path.join(folderPath, image))
+        .filter((img) => {
+            // 这里使用Array.from将Set类型转为数组
+            return Array.from(cover.imgFormat).some((item) => img.endsWith(item));
+        });
+
+    // 删除之前生成的商品主图背景
+    imagePaths.some((item, index) => {
+        if (item.endsWith('商品主图背景.png')) {
+            fs.rmSync(item, { force: true });
+            imagePaths.splice(index, 1);
+            return true;
+        }
+    });
+
+    if (imagePaths.length < 4) {
+        console.log(`当前1x1文件夹下少于4张图片`);
+        return;
+    }
+
+    //去掉多余的图片，只需要4张来拼背景
+    imagePaths.length = 4;
+    // 处理剩余的图片
+    const remainingImagesInfo = await Promise.all(
+        imagePaths.map(async (imagePath) => {
+            const { data, info } = await sharp(imagePath).resize({ width: 1000, fit: 'inside' }).toBuffer({ resolveWithObject: true });
+            return { data, info }; // 返回图片数据及其高度
+        })
+    );
+    // 获取第一张图片的高度
+    const { width, height } = remainingImagesInfo[0].info;
+    const outputImagePath = path.join(folderPath, `商品主图背景.png`);
+    await sharp({
+        create: {
+            width: width * 2, // 宽度使用第一张图片的宽度
+            height: height * 2, // 高度为两张图片的总高度
+            channels: 4,
+            background: { r: 255, g: 255, b: 255, alpha: 0 }, // 背景透明
+        },
+    })
+        .composite([
+            ...remainingImagesInfo.map(({ data, info }, index) => {
+                const currentRow = Math.floor(index / row);
+                const currentCol = index % row;
+                return {
+                    input: data,
+                    top: currentRow * info.height, // 计算纵向位置
+                    left: currentCol * info.width, // 计算横向位置
+                };
+            }),
+        ])
+        .toFile(outputImagePath);
+
+    console.log(`生成商品主图背景成功`);
+}
+
+mergeMainImgBg(scaleDir);