feat: EH Downloader 用 Go + Wails v2 重写

原 Electron 版在这台 Windows 机器上无法启动（0x80000003 崩在 V8 初始化），整个业务逻辑用 Go 重写，前端界面与协议结论完全保留。 - internal/eh: 协议核心，画廊页分页 -> /s/ -> hath 直链 -> 下载 - internal/core: 并发引擎 / 状态存储 / 目录模板 / 油猴桥口 - app.go: Wails 绑定层，替代 Electron IPC - frontend/js/api.js: 适配层，renderer.js 一行未改 - 37 个测试，含 httptest 模拟 EH 的端到端链路验证相比 Electron 版：90MB -> 12.4MB，180MB 内存 -> 27MB，构建 90s -> 2s。顺带修掉原版代理探测的 bug（永远返回第一个端口，从不等连接结果）。
2026-10-08 23:28:16 +08:00
commit 0f927147cd
42 changed files with 6805 additions and 0 deletions
@@ -0,0 +1,298 @@
+package core
+
+// 本地桥口：让油猴脚本把画廊地址推给本工具
+//
+//	POST /add        { gid, token, url, title }  +  X-EHDL-Token 头
+//	POST /add-batch  { items: [...] }            +  X-EHDL-Token 头
+//	GET  /ping                                     -> { ok: true }
+//	GET  /info                                     -> 端口/版本等信息
+//
+// 只监听 127.0.0.1，且同时校验 Origin 与固定 token，防止本机其他网页乱塞任务。
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+	"strings"
+	"sync"
+	"time"
+
+	"eh-downloader-wails/internal/eh"
+)
+
+// BridgeToken 固定 token（和油猴脚本里的 BRIDGE_TOKEN 保持一致）
+const BridgeToken = "ehdl-local-9f2a4c7e"
+
+var allowedOrigins = map[string]bool{
+	"https://e-hentai.org":      true,
+	"https://exhentai.org":      true,
+	"https://www.e-hentai.org": true,
+}
+
+const maxBody = 512 * 1024 // 批量最多 500 个，标题也要带，得给够
+
+// Bridge 是本地 HTTP 桥口
+type Bridge struct {
+	store   *Store
+	log     func(level, msg string)
+	onAdded func(t Task, added bool, batch bool)
+
+	mu     sync.Mutex
+	server *http.Server
+	port   int
+}
+
+// NewBridge 建桥口
+func NewBridge(store *Store, log func(string, string), onAdded func(Task, bool, bool)) *Bridge {
+	return &Bridge{store: store, log: log, onAdded: onAdded, port: 37777}
+}
+
+// Start 启动（只绑回环）
+func (b *Bridge) Start(port int) {
+	if port <= 0 {
+		port = 37777
+	}
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	b.port = port
+
+	mux := http.NewServeMux()
+	mux.HandleFunc("/ping", b.handlePing)
+	mux.HandleFunc("/info", b.handleInfo)
+	mux.HandleFunc("/add", b.handleAdd)
+	mux.HandleFunc("/add-batch", b.handleAddBatch)
+
+	srv := &http.Server{
+		Handler:           b.cors(mux),
+		ReadHeaderTimeout: 10 * time.Second,
+	}
+
+	ln, err := net.Listen("tcp", fmt.Sprintf("127.0.0.1:%d", port))
+	if err != nil {
+		if strings.Contains(err.Error(), "address already in use") {
+			b.log("warn", fmt.Sprintf("桥口端口 %d 被占用，油猴推送不可用。可在设置里改端口，或关掉占用它的程序。", port))
+		} else {
+			b.log("error", fmt.Sprintf("桥口启动失败：%v", err))
+		}
+		return
+	}
+
+	b.server = srv
+	go func() {
+		if err := srv.Serve(ln); err != nil && err != http.ErrServerClosed {
+			b.log("error", fmt.Sprintf("桥口异常：%v", err))
+		}
+	}()
+	b.log("info", fmt.Sprintf("本地桥口已就绪 http://127.0.0.1:%d（油猴推送可用）", port))
+}
+
+// Stop 停止桥口
+func (b *Bridge) Stop() {
+	b.mu.Lock()
+	srv := b.server
+	b.server = nil
+	b.mu.Unlock()
+	if srv != nil {
+		_ = srv.Close()
+	}
+}
+
+// Port 当前端口
+func (b *Bridge) Port() int {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	return b.port
+}
+
+// cors 处理 CORS 预检与响应头
+func (b *Bridge) cors(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		origin := r.Header.Get("Origin")
+		if origin != "" && allowedOrigins[origin] {
+			w.Header().Set("Access-Control-Allow-Origin", origin)
+			w.Header().Set("Vary", "Origin")
+		}
+		w.Header().Set("Access-Control-Allow-Methods", "GET, POST, OPTIONS")
+		w.Header().Set("Access-Control-Allow-Headers", "Content-Type, X-EHDL-Token")
+		if r.Method == http.MethodOptions {
+			w.WriteHeader(http.StatusNoContent)
+			return
+		}
+		next.ServeHTTP(w, r)
+	})
+}
+
+func writeJSON(w http.ResponseWriter, code int, v interface{}) {
+	body, _ := json.Marshal(v)
+	w.Header().Set("Content-Type", "application/json; charset=utf-8")
+	w.WriteHeader(code)
+	w.Write(body)
+}
+
+// readBody 读 JSON body（限大小）
+func readBody(r *http.Request) (map[string]interface{}, int) {
+	data, err := io.ReadAll(io.LimitReader(r.Body, maxBody+1))
+	if err != nil {
+		return nil, http.StatusBadRequest
+	}
+	if len(data) > maxBody {
+		return nil, http.StatusRequestEntityTooLarge
+	}
+	var m map[string]interface{}
+	if err := json.Unmarshal(data, &m); err != nil {
+		return nil, http.StatusBadRequest
+	}
+	return m, 0
+}
+
+func checkToken(w http.ResponseWriter, r *http.Request) bool {
+	if r.Header.Get("X-EHDL-Token") != BridgeToken {
+		writeJSON(w, http.StatusForbidden, map[string]interface{}{"ok": false, "error": "bad token"})
+		return false
+	}
+	return true
+}
+
+func (b *Bridge) handlePing(w http.ResponseWriter, r *http.Request) {
+	writeJSON(w, http.StatusOK, map[string]interface{}{"ok": true, "name": "EH Downloader"})
+}
+
+func (b *Bridge) handleInfo(w http.ResponseWriter, r *http.Request) {
+	writeJSON(w, http.StatusOK, map[string]interface{}{
+		"ok":      true,
+		"port":    b.Port(),
+		"version": AppVersion,
+	})
+}
+
+type batchItem struct {
+	GID   string `json:"gid"`
+	Token string `json:"token"`
+	URL   string `json:"url"`
+	Title string `json:"title"`
+}
+
+func (b *Bridge) handleAddBatch(w http.ResponseWriter, r *http.Request) {
+	if !checkToken(w, r) {
+		b.log("warn", "桥口收到 token 不正确的批量请求，已拒绝")
+		return
+	}
+	body, code := readBody(r)
+	if code != 0 {
+		writeJSON(w, code, map[string]interface{}{"ok": false, "error": "bad request"})
+		return
+	}
+
+	raw, _ := body["items"].([]interface{})
+	if len(raw) == 0 {
+		writeJSON(w, http.StatusBadRequest, map[string]interface{}{"ok": false, "error": "items 为空"})
+		return
+	}
+
+	seen := map[string]bool{}
+	var fresh []eh.GalleryRef
+	existed := 0
+
+	for _, it := range raw {
+		if len(fresh) >= 500 {
+			break
+		}
+		m, ok := it.(map[string]interface{})
+		if !ok {
+			continue
+		}
+		item := batchItem{
+			GID:   str(m["gid"]),
+			Token: str(m["token"]),
+			URL:   str(m["url"]),
+			Title: str(m["title"]),
+		}
+		if item.GID == "" || item.Token == "" {
+			continue
+		}
+		key := item.GID + "/" + item.Token
+		if seen[key] {
+			continue
+		}
+		seen[key] = true
+
+		if b.store.FindTask(item.GID, item.Token) != nil {
+			existed++
+			continue
+		}
+		fresh = append(fresh, eh.GalleryRef{GID: item.GID, Token: item.Token, Raw: item.URL, Title: item.Title})
+	}
+
+	added := b.store.AddTasks(fresh)
+	for _, ref := range fresh {
+		if ref.Title != "" {
+			b.store.SetTitle(ref.GID, ref.Token, ref.Title)
+		}
+	}
+	b.store.ScheduleFlush(0)
+
+	for _, ref := range fresh {
+		if t := b.store.FindTask(ref.GID, ref.Token); t != nil && b.onAdded != nil {
+			b.onAdded(*t, true, true)
+		}
+	}
+
+	writeJSON(w, http.StatusOK, map[string]interface{}{
+		"ok":       true,
+		"added":    added,
+		"existed":  existed,
+		"received": len(raw),
+		"invalid":  len(raw) - len(seen),
+	})
+}
+
+func (b *Bridge) handleAdd(w http.ResponseWriter, r *http.Request) {
+	if !checkToken(w, r) {
+		b.log("warn", "桥口收到 token 不正确的请求，已拒绝")
+		return
+	}
+	body, code := readBody(r)
+	if code != 0 {
+		writeJSON(w, code, map[string]interface{}{"ok": false, "error": "bad request"})
+		return
+	}
+
+	gid := strings.TrimSpace(str(body["gid"]))
+	token := strings.TrimSpace(str(body["token"]))
+	if gid == "" || token == "" {
+		writeJSON(w, http.StatusBadRequest, map[string]interface{}{"ok": false, "error": "缺少 gid 或 token"})
+		return
+	}
+
+	exists := b.store.FindTask(gid, token) != nil
+	added := b.store.AddTasks([]eh.GalleryRef{{GID: gid, Token: token, Raw: str(body["url"])}})
+	if t := str(body["title"]); t != "" {
+		b.store.SetTitle(gid, token, t)
+	}
+	b.store.ScheduleFlush(0)
+
+	if t := b.store.FindTask(gid, token); t != nil && b.onAdded != nil {
+		b.onAdded(*t, added > 0, false)
+	}
+
+	queued := false
+	if t := b.store.FindTask(gid, token); t != nil {
+		queued = t.Status == "queued"
+	}
+
+	writeJSON(w, http.StatusOK, map[string]interface{}{
+		"ok":      true,
+		"added":   added > 0,
+		"existed": exists,
+		"gid":     gid,
+		"queued":  queued,
+	})
+}
+
+// str 安全取字符串
+func str(v interface{}) string {
+	s, _ := v.(string)
+	return s
+}