package api

import (
	"encoding/json"
	"log/slog"
	"net/http"
	"time"

	"github.com/sandrodach/mindsift/internal/auth"
	"github.com/sandrodach/mindsift/internal/storage"
)

// startDoneCleanupTicker deletes completed tasks whose delay ran out (storage/done_cleanup.go), once
// shortly after the start and then every hour.
func (s *Server) startDoneCleanupTicker() {
	time.Sleep(2 * time.Minute)
	s.runDoneCleanup(time.Now())
	ticker := time.NewTicker(time.Hour)
	defer ticker.Stop()
	for now := range ticker.C {
		s.runDoneCleanup(now)
	}
}

func (s *Server) runDoneCleanup(now time.Time) {
	deleted, err := s.store.PurgeExpiredDoneTasks(now)
	if err != nil {
		slog.Error("Aufräumen erledigter Aufgaben fehlgeschlagen", "error", err)
		return
	}
	if len(deleted) > 0 {
		slog.Info("Erledigte Aufgaben aufgeräumt", "count", len(deleted))
	}
	s.broadcastDeletedTasks(deleted)
}

// broadcastDeletedTasks tells everyone who saw the tasks; there are no watcher notifications for this.
func (s *Server) broadcastDeletedTasks(deleted []storage.DeletedTask) {
	for _, d := range deleted {
		audience := append(s.store.GetTaskListUserIDs(d.TaskListID), d.UserID)
		s.wsHub.BroadcastToUsers(audience, "TASK_DELETED", map[string]string{"id": d.ID})
	}
}

// handleClearDoneTasks: "Erledigte leeren" for one task list (taskListId) or all the user can edit.
func (s *Server) handleClearDoneTasks(w http.ResponseWriter, r *http.Request) {
	userID := auth.GetUserID(r.Context())
	var req struct {
		TaskListID string `json:"taskListId"`
	}
	_ = json.NewDecoder(r.Body).Decode(&req)
	deleted, err := s.store.ClearDoneTasks(userID, req.TaskListID)
	if err != nil {
		writeStoreError(w, http.StatusBadRequest, err)
		return
	}
	s.broadcastDeletedTasks(deleted)
	writeJSON(w, http.StatusOK, map[string]int{"deleted": len(deleted)})
}