const fs = require('fs');
const path = require('path');
const { execSync } = require('child_process');

// 检查并安装依赖
function ensureDependencies() {
    const dependencies = {
        'csv-parse': '^4.16.3',
        'axios': '^1.6.0'
    };
    
    const packageJsonPath = path.join(__dirname, 'package.json');
    const nodeModulesPath = path.join(__dirname, 'node_modules');
    
    // 检查package.json是否存在
    if (!fs.existsSync(packageJsonPath)) {
        console.log('创建package.json...');
        const packageJson = {
            name: 'yahoo-goods-export',
            version: '1.0.0',
            private: true,
            dependencies: dependencies
        };
        fs.writeFileSync(packageJsonPath, JSON.stringify(packageJson, null, 2));
    }
    
    // 检查node_modules是否存在
    if (!fs.existsSync(nodeModulesPath)) {
        console.log('安装依赖，这可能需要几分钟...');
        try {
            execSync('npm install', { cwd: __dirname, stdio: 'inherit' });
            console.log('依赖安装完成');
        } catch (error) {
            console.error('依赖安装失败:', error.message);
            process.exit(1);
        }
    }
}

// 确保依赖已安装
ensureDependencies();

// 现在导入依赖
const { parse } = require('csv-parse/sync');
const axios = require('axios');

async function downloadImage(url, filepath, retries = 3) {
    for (let attempt = 1; attempt <= retries; attempt++) {
        try {
            const response = await axios({
                url,
                method: 'GET',
                responseType: 'stream',
                timeout: 50000, // 50秒超时
                maxContentLength: 50 * 1024 * 1024, // 50MB最大文件限制
                headers: {
                    'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.124 Safari/537.36'
                }
            });
            
            await new Promise((resolve, reject) => {
                const writer = fs.createWriteStream(filepath);
                
                response.data.on('error', error => {
                    writer.close();
                    reject(error);
                });

                writer.on('error', error => {
                    writer.close();
                    reject(error);
                });
                
                writer.on('finish', resolve);
                
                response.data.pipe(writer);
            });
            
            return true;
            
        } catch (error) {
            console.error(`下载失败 (尝试 ${attempt}/${retries}): ${url}`, error.message);
            
            if (attempt === retries) {
                throw new Error(`下载失败 (已重试${retries}次): ${error.message}`);
            }
            
            // 等待一段时间后重试
            await new Promise(resolve => setTimeout(resolve, 2000 * attempt));
        }
    }
}

async function processCSV() {
    const csvFilePath = path.join(__dirname, '2025-02-07商城商品.csv');
    const progressFile = path.join(__dirname, 'progress.json');
    
    // 读取进度
    let lastProcessedRow = 0;
    if (fs.existsSync(progressFile)) {
        try {
            const progress = JSON.parse(fs.readFileSync(progressFile, 'utf8'));
            lastProcessedRow = progress.lastRow || 0;
            console.log(`从上次进度继续：第 ${lastProcessedRow} 行`);
        } catch (error) {
            console.error('读取进度文件失败:', error);
        }
    }

    // 添加文件存在检查
    if (!fs.existsSync(csvFilePath)) {
        throw new Error(`CSV文件不存在: ${csvFilePath}`);
    }

    console.log('开始处理CSV文件...');
    console.log(`CSV文件路径: ${csvFilePath}`);

    const fileContent = fs.readFileSync(csvFilePath);
    const records = parse(fileContent, {
        skip_empty_lines: true,
        relax_quotes: true,
        relax_column_count: true,
        encoding: 'utf8',
        bom: true
    });

    console.log(`总行数: ${records.length}`);

    // 获取列索引
    const headers = records[0];
    const codeIndex = headers.indexOf('code');  // C列
    const imageUrlsIndex = headers.indexOf('item-image-urls');  // CS列

    console.log('code列索引:', codeIndex);
    console.log('item-image-urls列索引:', imageUrlsIndex);

    // 创建goods文件夹
    const goodsDir = path.join(__dirname, 'goods');
    if (!fs.existsSync(goodsDir)) {
        fs.mkdirSync(goodsDir);
    }

    // 从上次处理的位置继续
    for (let i = Math.max(1, lastProcessedRow); i < records.length; i++) {
        console.log(`\n正在处理第 ${i + 1}/${records.length} 行`);
        try {
            const record = records[i];
            
            // 添加记录长度检查
            if (!record || record.length < Math.max(codeIndex, imageUrlsIndex) + 1) {
                console.log(`第${i + 1}行: 数据不完整，跳过`);
                continue;
            }

            const folderName = record[codeIndex];
            const imageUrls = record[imageUrlsIndex];

            if (!folderName || folderName.trim() === '') {
                console.log(`第${i + 1}行: code列为空，跳过`);
                continue;
            }

            if (!imageUrls || imageUrls.trim() === '') {
                console.log(`第${i + 1}行: item-image-urls列为空，跳过`);
                continue;
            }

            // 创建文件夹
            const folderPath = path.join(goodsDir, folderName.trim());
            if (!fs.existsSync(folderPath)) {
                fs.mkdirSync(folderPath, { recursive: true });
                console.log(`创建文件夹: ${folderPath}`);
            }

            // 处理图片链接
            const imageUrlList = imageUrls
                .split(';')
                .map(url => url.trim())
                .filter(url => url && url.length > 0);

            console.log(`[${i + 1}/${records.length}] 文件夹 ${folderName} 找到${imageUrlList.length}个图片链接`);

            // 下载图片
            for (let j = 0; j < imageUrlList.length; j++) {
                try {
                    const imageUrl = imageUrlList[j];
                    const filename = `image_${j + 1}${path.extname(imageUrl) || '.jpg'}`;
                    const filepath = path.join(folderPath, filename);

                    if (fs.existsSync(filepath)) {
                        console.log(`[${i + 1}/${records.length}] 图片已存在，跳过: ${filepath}`);
                        continue;
                    }

                    console.log(`[${i + 1}/${records.length}] 正在下载: ${imageUrl}`);
                    await downloadImage(imageUrl, filepath);
                    console.log(`[${i + 1}/${records.length}] 已保存到: ${filepath}`);
                    
                    // 添加下载间隔，避免请求过于频繁
                    await new Promise(resolve => setTimeout(resolve, 1500));
                    
                } catch (error) {
                    console.error(`图片下载失败 [行 ${i + 1}, 图片 ${j + 1}]:`, error.message);
                    continue;
                }
            }

            // 保存进度
            fs.writeFileSync(progressFile, JSON.stringify({ lastRow: i }));
            
        } catch (error) {
            console.error(`处理第 ${i + 1} 行时出错:`, error);
            // 保存进度后继续处理下一行
            fs.writeFileSync(progressFile, JSON.stringify({ lastRow: i }));
            continue;
        }
    }
    
    console.log('\nCSV处理完成！');
    // 处理完成后删除进度文件
    if (fs.existsSync(progressFile)) {
        fs.unlinkSync(progressFile);
    }
}

// 运行程序
processCSV().catch(error => {
    console.error('程序出错:', error);
});