package logweb

import (
	"encoding/json"
	"fmt"
	"io/fs"
	"log"
	"net/http"
	"strconv"
	"strings"

	"xk-hy-transit-go/internal/applog"
	"xk-hy-transit-go/internal/config"
	"xk-hy-transit-go/internal/db"
	"xk-hy-transit-go/internal/hy"
	syncer "xk-hy-transit-go/internal/sync"
	"xk-hy-transit-go/internal/syncgate"
)

// Runner 同步执行器（与 serve 共用）。
type Runner interface {
	Run(step, anchorDate string) error
}

// Deps Web 控制台依赖。
type Deps struct {
	LogDir    string
	Store     *db.Store
	Runner    Runner
	Cfg       config.Config
	AllowTest bool
	MySQLOK   bool
	MySQLErr  string
}

// Server HTTP 控制台。
type Server struct {
	deps Deps
	mux  *http.ServeMux
}

// NewServer 创建服务。
func NewServer(deps Deps) *Server {
	if deps.LogDir == "" {
		deps.LogDir = applog.Dir()
	}
	s := &Server{deps: deps, mux: http.NewServeMux()}
	s.routes()
	return s
}

func (s *Server) routes() {
	sub, _ := fs.Sub(webFS, "web")
	fileServer := http.FileServer(http.FS(sub))

	s.mux.HandleFunc("/", s.handleIndex)
	s.mux.HandleFunc("/logs", s.handlePage("logs.html"))
	s.mux.HandleFunc("/logs/view", s.handlePage("logs_view.html"))
	s.mux.HandleFunc("/runs", s.handlePage("runs.html"))
	s.mux.HandleFunc("/runs/record", s.handlePage("runs_record.html"))
	s.mux.HandleFunc("/test", s.handlePage("test.html"))

	s.mux.HandleFunc("/api/meta", s.handleAPIMeta)
	s.mux.HandleFunc("/api/dates", s.handleAPIDates)
	s.mux.HandleFunc("/api/log", s.handleAPILog)
	s.mux.HandleFunc("/api/runs", s.handleAPIRuns)
	s.mux.HandleFunc("/api/runs/record", s.handleAPIRecord)
	s.mux.HandleFunc("/api/runs/truncate", s.handleAPIRunsTruncate)
	s.mux.HandleFunc("/api/test/status", s.handleAPITestStatus)
	s.mux.HandleFunc("/api/test/sync", s.handleAPITestSync)

	s.mux.Handle("/static/", http.StripPrefix("/static/", fileServer))
}

func (s *Server) handlePage(name string) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		b, err := webFS.ReadFile("web/" + name)
		if err != nil {
			http.NotFound(w, r)
			return
		}
		w.Header().Set("Content-Type", "text/html; charset=utf-8")
		_, _ = w.Write(b)
	}
}

func (s *Server) handleIndex(w http.ResponseWriter, r *http.Request) {
	if r.URL.Path != "/" {
		http.NotFound(w, r)
		return
	}
	s.handlePage("index.html")(w, r)
}

func (s *Server) handleAPIMeta(w http.ResponseWriter, r *http.Request) {
	writeJSON(w, map[string]any{
		"logDir":          s.deps.LogDir,
		"mysqlOk":         s.deps.MySQLOK,
		"mysqlError":      s.deps.MySQLErr,
		"allowTest":       s.deps.AllowTest && s.deps.Runner != nil,
		"allowTruncate":   s.deps.Store != nil && s.deps.MySQLOK,
		"hasRunner":       s.deps.Runner != nil,
		"stepOptions":     hy.StepSelectOptions(),
		"testStepOptions": hy.TestStepSelectOptions(),
		"logKindOptions":  []map[string]string{{"value": "app", "label": "应用"}, {"value": "pull", "label": "拉取"}, {"value": "push", "label": "推送"}},
	})
}

func (s *Server) handleAPIDates(w http.ResponseWriter, r *http.Request) {
	kind := r.URL.Query().Get("kind")
	dates, err := ListLogDates(s.deps.LogDir, kind)
	if err != nil {
		writeErr(w, 400, err.Error())
		return
	}
	writeJSON(w, dates)
}

func (s *Server) handleAPILog(w http.ResponseWriter, r *http.Request) {
	kind := r.URL.Query().Get("kind")
	date := r.URL.Query().Get("date")
	meta, lines, err := ReadLogFile(s.deps.LogDir, kind, date)
	if err != nil {
		writeErr(w, 404, err.Error())
		return
	}
	writeJSON(w, map[string]any{
		"meta":  meta,
		"lines": ParseLogLines(lines),
	})
}

func (s *Server) handleAPIRuns(w http.ResponseWriter, r *http.Request) {
	if s.deps.Store == nil {
		writeErr(w, 503, "MySQL 未连接")
		return
	}
	limit, _ := strconv.Atoi(r.URL.Query().Get("limit"))
	items, err := ListRuns(s.deps.Store, r.URL.Query().Get("anchor_date"), r.URL.Query().Get("step"), limit)
	if err != nil {
		writeErr(w, 500, err.Error())
		return
	}
	jobs, _ := s.deps.Store.ListJobs(30, r.URL.Query().Get("anchor_date"), r.URL.Query().Get("step"))
	writeJSON(w, map[string]any{"items": items, "jobs": enrichJobs(jobs)})
}

func (s *Server) handleAPIRecord(w http.ResponseWriter, r *http.Request) {
	if s.deps.Store == nil {
		writeErr(w, 503, "MySQL 未连接")
		return
	}
	id, _ := strconv.ParseInt(r.URL.Query().Get("id"), 10, 64)
	if id <= 0 {
		writeErr(w, 400, "invalid id")
		return
	}
	detail, err := GetRecordDetail(s.deps.Store, id)
	if err != nil {
		writeErr(w, 404, err.Error())
		return
	}
	writeJSON(w, detail)
}

func (s *Server) handleAPIRunsTruncate(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodPost {
		writeErr(w, 405, "POST only")
		return
	}
	if s.deps.Store == nil || !s.deps.MySQLOK {
		writeErr(w, 503, "MySQL 未连接")
		return
	}
	if syncgate.IsRunning() {
		writeErr(w, 409, "已有同步任务在执行中")
		return
	}
	if err := s.deps.Store.TruncateAuditTables(); err != nil {
		applog.Appf("web truncate audit tables failed: %v", err)
		writeErr(w, 500, err.Error())
		return
	}
	applog.Appf("web truncate audit tables ok")
	writeJSON(w, map[string]any{
		"ok":     true,
		"tables": []string{"hy_push_log", "hy_push_record", "hy_sync_job"},
	})
}

func (s *Server) handleAPITestStatus(w http.ResponseWriter, r *http.Request) {
	writeJSON(w, enrichTestStatus(syncgate.GetStatus()))
}

func (s *Server) handleAPITestSync(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodPost {
		writeErr(w, 405, "POST only")
		return
	}
	if !s.deps.AllowTest || s.deps.Runner == nil {
		writeErr(w, 403, "测试同步未启用或未配置 Runner（请使用 transit serve）")
		return
	}
	var body struct {
		Step string `json:"step"`
		Date string `json:"date"`
	}
	if err := json.NewDecoder(r.Body).Decode(&body); err != nil {
		writeErr(w, 400, "invalid json")
		return
	}
	step := strings.TrimSpace(body.Step)
	if step == "" {
		step = "all"
	}
	anchor := syncer.ResolveAnchorDate(s.deps.Cfg, strings.TrimSpace(body.Date))
	runner := s.deps.Runner
	if !syncgate.TryRun(step, anchor, func() error {
		applog.RunSeparator(fmt.Sprintf("BEGIN web-test step=%s date=%s", step, anchor))
		applog.Appf("web test sync start step=%s date=%s", step, anchor)
		err := runner.Run(step, anchor)
		if err != nil {
			applog.Appf("web test sync failed step=%s date=%s err=%v", step, anchor, err)
			applog.RunSeparator(fmt.Sprintf("END web-test step=%s date=%s ok=false", step, anchor))
			return err
		}
		applog.Appf("web test sync done step=%s date=%s", step, anchor)
		applog.RunSeparator(fmt.Sprintf("END web-test step=%s date=%s ok=true", step, anchor))
		return nil
	}) {
		writeErr(w, 409, "已有同步任务在执行中")
		return
	}
	writeJSON(w, map[string]any{"ok": true, "step": step, "date": anchor})
}

// Run 启动 HTTP 服务（阻塞）。
func Run(addr string, deps Deps) error {
	s := NewServer(deps)
	log.Printf("logweb: 控制台 http://%s/", addr)
	return http.ListenAndServe(addr, s.mux)
}

func writeJSON(w http.ResponseWriter, v any) {
	w.Header().Set("Content-Type", "application/json; charset=utf-8")
	enc := json.NewEncoder(w)
	enc.SetIndent("", "  ")
	_ = enc.Encode(v)
}

func writeErr(w http.ResponseWriter, code int, msg string) {
	w.Header().Set("Content-Type", "application/json; charset=utf-8")
	w.WriteHeader(code)
	_ = json.NewEncoder(w).Encode(map[string]string{"error": msg})
}