chenxin
84bd3238ab
- 新增 /rank 免签名榜单接口（多域名容错）、/bookshelf 与 /read-history（sessionid 登录态，书架支持分组过滤） - 搜索重写：翻页透传上游 passback/search_id/next_offset/corrected_query 并按 book_id 去重，15~20 位纯数字关键词直查详情（ID 直搜） - 删除 /login/check 登录校验端点（login.go、路由与文档同步移除，sessionid 说明改为直接供书架/历史使用） - 正文链路重构：singleflight 合并同章节并发回源防击穿，缓存与解析解耦统一在出口处理，decodeContentBody 按 crypt_status 分支并兜底 500003 明文 - 缓存层：SQL 持久层 TTL 与业务 TTL 解耦（不可变内容过期后由 SQL 回填），动态短缓存只走 Redis，withCache 合并并发 miss - 密钥池：KeyTs 随正文请求上传降低密钥不匹配重试，密钥超 24 小时异步刷新并防刷新风暴，last_used_at 批量落库 - 签名补 X-Helios（与 X-Ladon 同值，对齐书源实现）；设备注册版本号统一走 ClientVersionCode/Name - 分类 landing 透传新版标签 selected_items；multi-detail 批量详情供书架/历史复用 - README 与 openapi.yaml 补充新接口文档
626 lines
17 KiB
Go
626 lines
17 KiB
Go
package fqapi
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import (
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"bytes"
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"compress/gzip"
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"crypto/aes"
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"crypto/cipher"
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"encoding/base64"
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"encoding/hex"
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"encoding/json"
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"fmt"
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"io"
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"net/http"
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"strings"
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"sync"
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"time"
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"fanqie/internal/common"
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"fanqie/internal/config"
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)
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var (
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mangaLogger = common.NewLogger("manga", "INFO", "")
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// 存储漫画图片信息的缓存（用于代理模式）
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mangaImageCache = make(map[string]*MangaImageInfo)
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mangaCacheMutex sync.RWMutex
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)
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// MangaImageInfo 漫画图片信息
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type MangaImageInfo struct {
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PicURL string
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EncryptKey string
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Width int
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Height int
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CachedAt time.Time
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}
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// MangaData 漫画数据结构
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type MangaData struct {
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PicInfos []PicInfo `json:"picInfos"`
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EncryptKey string `json:"encrypt_key"`
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}
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// PicInfo 图片信息
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type PicInfo struct {
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PicURL string `json:"picUrl"`
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Md5 string `json:"md5"`
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Width int `json:"width"`
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Height int `json:"height"`
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}
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// ImageResult 图片结果
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type ImageResult struct {
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Data string `json:"data"`
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Width int `json:"width"`
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Height int `json:"height"`
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Format string `json:"format"`
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Index int `json:"index"`
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}
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// HandleGetManga 处理漫画请求
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func HandleGetManga(itemID string, showHTML bool, urlOutputMode string) (interface{}, error) {
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return getMangaWithRetry(itemID, showHTML, urlOutputMode, 0)
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}
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// getMangaWithRetry 获取漫画内容，支持设备切换重试
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func getMangaWithRetry(itemID string, showHTML bool, urlOutputMode string, retryCount int) (interface{}, error) {
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// 防止无限递归
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const maxRetries = 5
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if retryCount >= maxRetries {
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mangaLogger.Warning(fmt.Sprintf("已重试 %d 次，获取漫画失败", maxRetries))
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return nil, fmt.Errorf("已重试 %d 次，所有设备均失败", maxRetries)
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}
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// 1. 从设备密钥池获取设备
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pool := GetDeviceKeyPool()
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item, err := pool.GetNext()
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if err != nil {
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return nil, fmt.Errorf("从设备池获取设备失败: %w", err)
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}
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header := item.DeviceHeader
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keyInfo := &KeyInfo{
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Key: item.Key,
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Ver: item.KeyVer,
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}
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mangaLogger.Debug(fmt.Sprintf("使用池中设备 ID=%d (重试次数: %d)", item.ID, retryCount))
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// 2. 构建URL - 使用 BuildURL 添加设备参数
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headerWithoutVersion := removeVersionFromHeader(header)
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url := BuildURL("https://reading.snssdk.com/reading/reader/full/v/",
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"aid=1967",
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"app_name=novelapp",
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"channel=0",
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"device_platform=android",
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"version_code=66.9",
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"item_id="+itemID,
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"os_version=0",
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headerWithoutVersion,
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)
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// 3. 调用API - 使用 GorgonRequest 添加签名
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response, err := GorgonRequest(url, map[string]interface{}{
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"method": "GET",
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"headers": map[string]string{
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"User-Agent": "com.dragon.read",
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},
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})
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if err != nil {
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mangaLogger.Warning(fmt.Sprintf("API请求失败，切换设备重试: %v", err))
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pool.MarkInvalid(header)
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pool.RemoveInvalid()
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return getMangaWithRetry(itemID, showHTML, urlOutputMode, retryCount+1)
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}
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// 4. 解析响应
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var body map[string]interface{}
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if err := json.Unmarshal(response.Content, &body); err != nil {
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mangaLogger.Warning(fmt.Sprintf("JSON解析失败，切换设备重试: %v", err))
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pool.MarkInvalid(header)
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pool.RemoveInvalid()
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return getMangaWithRetry(itemID, showHTML, urlOutputMode, retryCount+1)
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}
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// 5. 获取加密的content
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data, ok := body["data"].(map[string]interface{})
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if !ok {
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mangaLogger.Warning("响应data字段无效，切换设备重试")
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pool.MarkInvalid(header)
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pool.RemoveInvalid()
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return getMangaWithRetry(itemID, showHTML, urlOutputMode, retryCount+1)
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}
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encryptedContent, ok := data["content"].(string)
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if !ok || encryptedContent == "Invalid" {
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mangaLogger.Warning(fmt.Sprintf("内容返回 Invalid，标记设备无效并切换设备 (重试: %d)", retryCount))
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pool.MarkInvalid(header)
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pool.RemoveInvalid()
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return getMangaWithRetry(itemID, showHTML, urlOutputMode, retryCount+1)
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}
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// 检查密钥版本
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if keyVersion, ok := data["key_version"].(float64); ok {
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if int(keyVersion) != keyInfo.Ver {
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mangaLogger.Warning("密钥版本不匹配，重新获取密钥")
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newKeyInfo, err := GetKey(header)
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if err == nil {
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UpdateKeyInPool(header, newKeyInfo)
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keyInfo = newKeyInfo
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} else {
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mangaLogger.Warning("获取密钥失败，切换设备重试")
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pool.MarkInvalid(header)
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pool.RemoveInvalid()
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return getMangaWithRetry(itemID, showHTML, urlOutputMode, retryCount+1)
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}
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}
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}
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// 6. 解密content
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decrypted, err := decryptAESContent(encryptedContent, keyInfo.Key)
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if err != nil {
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mangaLogger.Warning(fmt.Sprintf("解密失败，切换设备重试: %v", err))
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pool.MarkInvalid(header)
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pool.RemoveInvalid()
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return getMangaWithRetry(itemID, showHTML, urlOutputMode, retryCount+1)
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}
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// 7. 判断是否为漫画内容
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if strings.Contains(decrypted, "picInfos") {
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// 是漫画，决定输出模式
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// 优先级：URL参数 > 配置文件 > 默认值
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outputMode := "proxy" // 默认值
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// 从配置文件读取
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cfg := config.GetConfig()
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if cfg != nil && cfg.Fanqie.Manga.OutputMode != "" {
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outputMode = cfg.Fanqie.Manga.OutputMode
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}
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// URL参数优先级最高
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if urlOutputMode != "" {
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outputMode = urlOutputMode
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}
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// 解析漫画图片（传入keyInfo用于解密模式）
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images, err := parseMangaImages(decrypted, showHTML, outputMode, itemID, keyInfo)
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if err != nil {
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return nil, fmt.Errorf("解析漫画失败: %w", err)
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}
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return images, nil
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}
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// 不是漫画，返回普通文本
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return map[string]interface{}{
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"content": decrypted,
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}, nil
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}
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// decryptAESContent 使用AES-128-CBC解密content
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func decryptAESContent(encrypted, secretKey string) (string, error) {
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// Base64解码加密内容
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raw, err := base64.StdEncoding.DecodeString(encrypted)
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if err != nil {
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return "", fmt.Errorf("Base64解码失败: %w", err)
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}
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if len(raw) < 16 {
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return "", fmt.Errorf("数据长度不足")
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}
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// 提取IV和密文
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iv := raw[:16]
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ciphertext := raw[16:]
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// Base64解码密钥
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keyBytes, err := base64.StdEncoding.DecodeString(secretKey)
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if err != nil {
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return "", fmt.Errorf("密钥解码失败: %w", err)
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}
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if len(keyBytes) != 16 {
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return "", fmt.Errorf("密钥长度必须为16字节，实际: %d", len(keyBytes))
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}
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// 创建AES cipher
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block, err := aes.NewCipher(keyBytes)
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if err != nil {
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return "", fmt.Errorf("创建cipher失败: %w", err)
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}
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// CBC模式解密
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mode := cipher.NewCBCDecrypter(block, iv)
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plaintext := make([]byte, len(ciphertext))
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mode.CryptBlocks(plaintext, ciphertext)
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// PKCS7 unpadding（无效填充说明密钥不匹配，返回错误触发上层重试）
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plaintext = pkcs7Unpad(plaintext)
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if plaintext == nil {
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return "", fmt.Errorf("解密失败（无效填充，密钥可能不匹配）")
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}
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// 尝试gzip解压
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if len(plaintext) > 2 && plaintext[0] == 0x1f && plaintext[1] == 0x8b {
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// 是gzip压缩的数据
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reader, err := gzip.NewReader(bytes.NewReader(plaintext))
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if err == nil {
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defer reader.Close()
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decompressed, err := io.ReadAll(reader)
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if err == nil {
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return string(decompressed), nil
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}
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}
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}
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return string(plaintext), nil
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}
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// pkcs7Unpad PKCS7 unpadding
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func pkcs7Unpad(data []byte) []byte {
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length := len(data)
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if length == 0 {
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return nil
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}
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unpadding := int(data[length-1])
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// 完整校验：值 1-16 且尾部 unpadding 个字节全等于填充值。
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// 密钥错误时解密结果是随机字节，弱校验会让乱码静默通过
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if unpadding < 1 || unpadding > 16 || unpadding > length {
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return nil
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}
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for _, b := range data[length-unpadding:] {
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if int(b) != unpadding {
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return nil
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}
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}
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return data[:length-unpadding]
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}
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// buildMangaResponse 构建漫画响应（统一HTML和JSON格式输出）
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func buildMangaResponse(images []ImageResult, showHTML bool) interface{} {
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if showHTML {
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var htmlContent strings.Builder
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for _, img := range images {
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htmlContent.WriteString(fmt.Sprintf(`<img src="%s" width="%d" height="%d" alt="图片%d">`,
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img.Data, img.Width, img.Height, img.Index))
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htmlContent.WriteString("\n")
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}
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return map[string]interface{}{
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"content": htmlContent.String(),
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}
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}
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return map[string]interface{}{
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"images": images,
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}
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}
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// processURLMode 处理URL模式（MD5直链）
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func processURLMode(mangaData *MangaData) []ImageResult {
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baseDomain := "https://p6-novel.byteimg.com/origin/"
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validPath := detectMangaPath(baseDomain, mangaData.PicInfos[0].Md5)
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images := make([]ImageResult, len(mangaData.PicInfos))
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for i, pic := range mangaData.PicInfos {
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imageURL := baseDomain + validPath + pic.Md5
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images[i] = ImageResult{
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Data: imageURL,
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Width: pic.Width,
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Height: pic.Height,
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Format: "unknown",
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Index: i,
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}
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}
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return images
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}
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// processProxyMode 处理代理模式（生成短URL并缓存）
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func processProxyMode(mangaData *MangaData, itemID string) []ImageResult {
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images := make([]ImageResult, len(mangaData.PicInfos))
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for i, pic := range mangaData.PicInfos {
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cacheKey := fmt.Sprintf("%s_%d", itemID, i)
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// 存储图片信息到缓存
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mangaCacheMutex.Lock()
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mangaImageCache[cacheKey] = &MangaImageInfo{
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PicURL: pic.PicURL,
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EncryptKey: mangaData.EncryptKey,
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Width: pic.Width,
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Height: pic.Height,
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CachedAt: time.Now(),
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}
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mangaCacheMutex.Unlock()
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// 返回短的代理URL
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imageData := fmt.Sprintf("/manga/image/%s/%d", itemID, i)
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images[i] = ImageResult{
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Data: imageData,
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Width: pic.Width,
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Height: pic.Height,
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Format: "unknown",
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Index: i,
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}
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}
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return images
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}
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// fillMangaCache 填充漫画图片缓存（供所有模式使用）
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func fillMangaCache(mangaData *MangaData, itemID string) {
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for i, pic := range mangaData.PicInfos {
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cacheKey := fmt.Sprintf("%s_%d", itemID, i)
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// 检查是否已经存在，避免覆盖
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mangaCacheMutex.RLock()
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_, exists := mangaImageCache[cacheKey]
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mangaCacheMutex.RUnlock()
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if exists {
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continue
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}
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// 存储图片信息到缓存
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mangaCacheMutex.Lock()
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mangaImageCache[cacheKey] = &MangaImageInfo{
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PicURL: pic.PicURL,
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EncryptKey: mangaData.EncryptKey,
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Width: pic.Width,
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Height: pic.Height,
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CachedAt: time.Now(),
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}
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mangaCacheMutex.Unlock()
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}
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}
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// processDataURIMode 处理DataURI模式（下载、解密、Base64编码）
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func processDataURIMode(mangaData *MangaData) []ImageResult {
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keyBytes, err := hex.DecodeString(mangaData.EncryptKey)
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if err != nil {
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mangaLogger.Warning(fmt.Sprintf("密钥解码失败: %v", err))
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return []ImageResult{}
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}
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images := make([]ImageResult, 0, len(mangaData.PicInfos))
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for i, pic := range mangaData.PicInfos {
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// 下载加密图片
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encryptedData, err := downloadImageWithRetry(pic.PicURL, 3)
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if err != nil {
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mangaLogger.Warning(fmt.Sprintf("下载图片失败 [%d]: %v", i, err))
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continue
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}
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// 解密图片
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decryptedData, err := decryptImage(encryptedData, keyBytes)
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if err != nil {
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mangaLogger.Warning(fmt.Sprintf("解密图片失败 [%d]: %v", i, err))
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continue
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}
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// 识别格式
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format := getImageFormat(decryptedData, pic.PicURL)
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// Base64编码图片数据
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base64Data := base64.StdEncoding.EncodeToString(decryptedData)
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// Data URI模式：返回完整的Base64编码
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mimeType := fmt.Sprintf("image/%s", format)
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if format == "jpg" {
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mimeType = "image/jpeg"
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}
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imageData := fmt.Sprintf("data:%s;base64,%s", mimeType, base64Data)
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images = append(images, ImageResult{
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Data: imageData,
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Width: pic.Width,
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Height: pic.Height,
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Format: format,
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Index: i,
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})
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}
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return images
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}
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// parseMangaImages 解析并处理漫画图片
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func parseMangaImages(content string, showHTML bool, outputMode string, itemID string, keyInfo *KeyInfo) (interface{}, error) {
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// 提取JSON部分
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jsonStart := strings.Index(content, "{")
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jsonEnd := strings.LastIndex(content, "}")
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if jsonStart == -1 || jsonEnd == -1 {
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return nil, fmt.Errorf("无法找到JSON数据")
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}
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jsonStr := content[jsonStart : jsonEnd+1]
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var mangaData MangaData
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if err := json.Unmarshal([]byte(jsonStr), &mangaData); err != nil {
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return nil, fmt.Errorf("JSON解析失败: %w", err)
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}
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if len(mangaData.PicInfos) == 0 {
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return nil, fmt.Errorf("未找到图片信息")
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}
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if mangaData.EncryptKey == "" {
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return nil, fmt.Errorf("缺少加密密钥")
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}
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// 根据不同模式处理图片
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var images []ImageResult
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switch outputMode {
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case "url":
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images = processURLMode(&mangaData)
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case "proxy":
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images = processProxyMode(&mangaData, itemID)
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default: // "data_uri"
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images = processDataURIMode(&mangaData)
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}
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// 无论什么模式，都填充缓存以便后续可以通过 /manga/image 访问
|
||
fillMangaCache(&mangaData, itemID)
|
||
|
||
return buildMangaResponse(images, showHTML), nil
|
||
}
|
||
|
||
// downloadImageWithRetry 带重试的图片下载
|
||
func downloadImageWithRetry(url string, maxRetries int) ([]byte, error) {
|
||
var lastErr error
|
||
|
||
for i := 0; i <= maxRetries; i++ {
|
||
data, err := downloadImage(url)
|
||
if err == nil && len(data) > 100 {
|
||
return data, nil
|
||
}
|
||
lastErr = err
|
||
if i < maxRetries {
|
||
// 重试间隔递增（2秒、4秒、6秒）
|
||
time.Sleep(time.Duration(i*2+2) * time.Second)
|
||
}
|
||
}
|
||
|
||
return nil, fmt.Errorf("下载失败（已重试%d次）: %w", maxRetries, lastErr)
|
||
}
|
||
|
||
// downloadImage 下载图片
|
||
func downloadImage(url string) ([]byte, error) {
|
||
// 创建专用的图片下载客户端，超时时间更长
|
||
client := &http.Client{
|
||
Timeout: 120 * time.Second,
|
||
}
|
||
|
||
req, err := http.NewRequest("GET", url, nil)
|
||
if err != nil {
|
||
return nil, err
|
||
}
|
||
|
||
// 使用与API一致的请求头
|
||
req.Header.Set("User-Agent", "okhttp/4.12.0")
|
||
req.Header.Set("Accept", "image/avif,image/webp,image/apng,image/svg+xml,image/*,*/*;q=0.8")
|
||
req.Header.Set("Accept-Encoding", "gzip, deflate")
|
||
req.Header.Set("Referer", "https://fanqie.novel.com/")
|
||
req.Header.Set("Origin", "https://fanqie.novel.com")
|
||
|
||
resp, err := client.Do(req)
|
||
if err != nil {
|
||
return nil, fmt.Errorf("下载失败: %v", err)
|
||
}
|
||
defer resp.Body.Close()
|
||
|
||
if resp.StatusCode != 200 {
|
||
return nil, fmt.Errorf("HTTP状态码: %d", resp.StatusCode)
|
||
}
|
||
|
||
return io.ReadAll(resp.Body)
|
||
}
|
||
|
||
// decryptImage 解密图片数据（AES-GCM）
|
||
func decryptImage(encryptedData, keyBytes []byte) ([]byte, error) {
|
||
// 加密格式: IV(12字节) + Ciphertext + Tag(16字节)
|
||
dataLen := len(encryptedData)
|
||
if dataLen < 28 {
|
||
return nil, fmt.Errorf("数据长度不足（至少需要28字节）")
|
||
}
|
||
|
||
// 提取各部分
|
||
iv := encryptedData[:12]
|
||
tag := encryptedData[dataLen-16:]
|
||
ciphertext := encryptedData[12 : dataLen-16]
|
||
|
||
// 创建AES cipher
|
||
block, err := aes.NewCipher(keyBytes)
|
||
if err != nil {
|
||
return nil, fmt.Errorf("创建cipher失败: %w", err)
|
||
}
|
||
|
||
// 创建GCM mode
|
||
aesGCM, err := cipher.NewGCM(block)
|
||
if err != nil {
|
||
return nil, fmt.Errorf("创建GCM失败: %w", err)
|
||
}
|
||
|
||
// 组合ciphertext和tag（Go的GCM要求tag附加在ciphertext后面）
|
||
ciphertextWithTag := append(ciphertext, tag...)
|
||
|
||
// 解密
|
||
plaintext, err := aesGCM.Open(nil, iv, ciphertextWithTag, nil)
|
||
if err != nil {
|
||
return nil, fmt.Errorf("解密失败: %w", err)
|
||
}
|
||
|
||
return plaintext, nil
|
||
}
|
||
|
||
// getImageFormat 识别图片格式
|
||
// detectMangaPath 探测正确的漫画图片路径（novel-images/ 或 novel-pic/）
|
||
func detectMangaPath(baseDomain, firstMd5 string) string {
|
||
// 优先尝试 novel-images/
|
||
testURL := baseDomain + "novel-images/" + firstMd5
|
||
|
||
client := &http.Client{
|
||
Timeout: 8 * time.Second,
|
||
}
|
||
|
||
resp, err := client.Get(testURL)
|
||
if err != nil {
|
||
// 请求失败，使用novel-pic/
|
||
return "novel-pic/"
|
||
}
|
||
defer resp.Body.Close()
|
||
|
||
// 读取响应内容
|
||
body, err := io.ReadAll(resp.Body)
|
||
if err != nil {
|
||
return "novel-pic/"
|
||
}
|
||
|
||
// 检查是否为JSON响应（错误响应通常是JSON）
|
||
var jsonData interface{}
|
||
if json.Unmarshal(body, &jsonData) == nil {
|
||
// 是JSON，说明路径无效，切换到novel-pic/
|
||
return "novel-pic/"
|
||
}
|
||
|
||
// 不是JSON，说明返回的是图片，路径有效
|
||
return "novel-images/"
|
||
}
|
||
|
||
func getImageFormat(data []byte, url string) string {
|
||
// 首先尝试从URL提取扩展名
|
||
if idx := strings.LastIndex(url, "."); idx != -1 {
|
||
ext := strings.ToLower(url[idx+1:])
|
||
// 移除query参数
|
||
if qIdx := strings.Index(ext, "?"); qIdx != -1 {
|
||
ext = ext[:qIdx]
|
||
}
|
||
if ext == "jpg" || ext == "jpeg" || ext == "png" || ext == "gif" || ext == "webp" {
|
||
return ext
|
||
}
|
||
}
|
||
|
||
// 通过文件头识别
|
||
if len(data) < 16 {
|
||
return "png"
|
||
}
|
||
|
||
// JPEG: FF D8 FF
|
||
if bytes.HasPrefix(data, []byte{0xFF, 0xD8, 0xFF}) {
|
||
return "jpg"
|
||
}
|
||
|
||
// PNG: 89 50 4E 47
|
||
if bytes.HasPrefix(data, []byte{0x89, 0x50, 0x4E, 0x47}) {
|
||
return "png"
|
||
}
|
||
|
||
// GIF: 47 49 46 38
|
||
if bytes.HasPrefix(data, []byte{0x47, 0x49, 0x46, 0x38}) {
|
||
return "gif"
|
||
}
|
||
|
||
// WEBP: RIFF...WEBP
|
||
if bytes.HasPrefix(data, []byte{0x52, 0x49, 0x46, 0x46}) &&
|
||
len(data) >= 12 &&
|
||
bytes.Equal(data[8:12], []byte{0x57, 0x45, 0x42, 0x50}) {
|
||
return "webp"
|
||
}
|
||
|
||
return "png"
|
||
}
|