package main

import (
	"encoding/json"
	"log"
	"net/http"
	"strconv"
)

// startWebUI 在独立端口起一个只读管理界面，对外提供 dashboard + JSON API。
// 单独端口避免和反代端口冲突（反代会把所有路径转发上游）。
func startWebUI(addr string, rec *Recorder) {
	mux := webMux(rec)
	log.Printf("Web 管理界面启动: http://%s", addr)
	if err := http.ListenAndServe(addr, mux); err != nil {
		log.Printf("[!] Web 管理界面退出: %v", err)
	}
}

// webMux 组装管理界面的路由，单独抽出便于测试。
func webMux(rec *Recorder) http.Handler {
	mux := http.NewServeMux()

	// 首页：dashboard HTML
	mux.HandleFunc("GET /", func(w http.ResponseWriter, r *http.Request) {
		if r.URL.Path != "/" {
			http.NotFound(w, r)
			return
		}
		w.Header().Set("Content-Type", "text/html; charset=utf-8")
		w.Write([]byte(dashboardHTML))
	})

	// 聚合统计
	mux.HandleFunc("GET /api/stats", func(w http.ResponseWriter, r *http.Request) {
		s, err := rec.Stats()
		if err != nil {
			writeErr(w, err)
			return
		}
		writeJSON(w, s)
	})

	// 记录列表（支持 model/format/status/limit/offset 过滤）
	mux.HandleFunc("GET /api/records", func(w http.ResponseWriter, r *http.Request) {
		q := r.URL.Query()
		opts := ListOptions{
			Model:  q.Get("model"),
			Format: q.Get("format"),
			Limit:  atoiDefault(q.Get("limit"), 100),
			Offset: atoiDefault(q.Get("offset"), 0),
			Status: atoiDefault(q.Get("status"), 0),
		}
		recs, total, err := rec.List(opts)
		if err != nil {
			writeErr(w, err)
			return
		}
		if recs == nil {
			recs = []Record{}
		}
		writeJSON(w, map[string]any{"total": total, "records": recs})
	})

	// 单条记录原文详情（含完整请求/响应）
	mux.HandleFunc("GET /api/records/{id}", func(w http.ResponseWriter, r *http.Request) {
		id, err := strconv.ParseInt(r.PathValue("id"), 10, 64)
		if err != nil {
			http.Error(w, "无效 id", http.StatusBadRequest)
			return
		}
		b, err := rec.ReadBlob(id)
		if err != nil {
			http.Error(w, err.Error(), http.StatusNotFound)
			return
		}
		writeJSON(w, b)
	})

	return mux
}

func writeJSON(w http.ResponseWriter, v any) {
	w.Header().Set("Content-Type", "application/json; charset=utf-8")
	if err := json.NewEncoder(w).Encode(v); err != nil {
		log.Printf("[!] 写 JSON 响应失败: %v", err)
	}
}

func writeErr(w http.ResponseWriter, err error) {
	http.Error(w, err.Error(), http.StatusInternalServerError)
}

func atoiDefault(s string, def int) int {
	if s == "" {
		return def
	}
	n, err := strconv.Atoi(s)
	if err != nil {
		return def
	}
	return n
}