package main

import (
	"context"
	"html/template"
	"log"
	"net/http"
	"os"
	"os/signal"
	"path/filepath"
	"syscall"
	"time"

	"github.com/alexedwards/scs/sqlite3store"
	"github.com/alexedwards/scs/v2"
	"github.com/go-chi/chi/v5"
	"github.com/go-chi/chi/v5/middleware"
	"github.com/joho/godotenv"

	"task-dashboard/internal/api"
	"task-dashboard/internal/auth"
	"task-dashboard/internal/config"
	"task-dashboard/internal/handlers"
	"task-dashboard/internal/store"
)

func main() {
	// Load .env file (ignore error if file doesn't exist - env vars might be set directly)
	_ = godotenv.Load()

	// Load configuration
	cfg, err := config.Load()
	if err != nil {
		log.Fatalf("Failed to load configuration: %v", err)
	}

	// Initialize database
	db, err := store.New(cfg.DatabasePath)
	if err != nil {
		log.Fatalf("Failed to initialize database: %v", err)
	}
	defer db.Close()

	// Initialize session manager
	sessionManager := scs.New()
	sessionManager.Store = sqlite3store.New(db.DB())
	sessionManager.Lifetime = 24 * time.Hour
	sessionManager.Cookie.Persist = true
	sessionManager.Cookie.Secure = !cfg.Debug
	sessionManager.Cookie.SameSite = http.SameSiteLaxMode

	// Initialize auth service
	authService := auth.NewService(db.DB())

	// Ensure default admin user exists (use env vars for credentials)
	defaultUser := os.Getenv("DEFAULT_USER")
	defaultPass := os.Getenv("DEFAULT_PASS")
	if defaultUser == "" {
		defaultUser = "admin"
	}
	if defaultPass == "" {
		defaultPass = "changeme"
	}
	if err := authService.EnsureDefaultUser(defaultUser, defaultPass); err != nil {
		log.Printf("Warning: failed to ensure default user: %v", err)
	}

	// Parse templates for auth handlers
	authTemplates, err := template.ParseGlob(filepath.Join(cfg.TemplateDir, "*.html"))
	if err != nil {
		log.Printf("Warning: failed to parse auth templates: %v", err)
	}

	// Initialize auth handlers
	authHandlers := auth.NewHandlers(authService, sessionManager, authTemplates)

	// Initialize API clients
	todoistClient := api.NewTodoistClient(cfg.TodoistAPIKey)
	trelloClient := api.NewTrelloClient(cfg.TrelloAPIKey, cfg.TrelloToken)

	var planToEatClient api.PlanToEatAPI
	if cfg.HasPlanToEat() {
		planToEatClient = api.NewPlanToEatClient(cfg.PlanToEatAPIKey)
	}

	var googleCalendarClient api.GoogleCalendarAPI
	if cfg.HasGoogleCalendar() {
		var err error
		googleCalendarClient, err = api.NewGoogleCalendarClient(context.Background(), cfg.GoogleCredentialsFile, cfg.GoogleCalendarID)
		if err != nil {
			log.Printf("Warning: failed to initialize Google Calendar client: %v", err)
		} else {
			log.Printf("Google Calendar client initialized for calendars: %s", cfg.GoogleCalendarID)
		}
	}

	// Initialize handlers
	h := handlers.New(db, todoistClient, trelloClient, planToEatClient, googleCalendarClient, cfg)
	tabsHandler := handlers.NewTabsHandler(db, googleCalendarClient, cfg.TemplateDir)

	// Set up router
	r := chi.NewRouter()

	// Global middleware
	r.Use(middleware.Logger)
	r.Use(middleware.Recoverer)
	r.Use(middleware.Timeout(60 * time.Second))
	r.Use(sessionManager.LoadAndSave)            // Session middleware must be applied globally
	r.Use(authHandlers.Middleware().CSRFProtect) // CSRF protection

	// Public routes (no auth required)
	r.Get("/login", authHandlers.HandleLoginPage)
	r.Post("/login", authHandlers.HandleLogin)
	r.Post("/logout", authHandlers.HandleLogout)

	// Serve static files (public)
	fileServer := http.FileServer(http.Dir(cfg.StaticDir))
	r.Handle("/static/*", http.StripPrefix("/static/", fileServer))

	// Protected routes (auth required)
	r.Group(func(r chi.Router) {
		r.Use(authHandlers.Middleware().RequireAuth)

		// Dashboard
		r.Get("/", h.HandleDashboard)
		r.Post("/api/refresh", h.HandleRefresh)
		r.Get("/api/tasks", h.HandleGetTasks)
		r.Get("/api/meals", h.HandleGetMeals)
		r.Get("/api/boards", h.HandleGetBoards)

		// Tab routes for HTMX
		r.Get("/tabs/tasks", tabsHandler.HandleTasks)
		r.Get("/tabs/planning", tabsHandler.HandlePlanning)
		r.Get("/tabs/meals", tabsHandler.HandleMeals)
		r.Post("/tabs/refresh", h.HandleRefreshTab)

		// Trello card operations
		r.Post("/cards", h.HandleCreateCard)
		r.Post("/cards/complete", h.HandleCompleteCard)

		// Todoist task operations
		r.Post("/tasks", h.HandleCreateTask)
		r.Post("/tasks/complete", h.HandleCompleteTask)

		// Unified task completion (for Tasks tab Atoms)
		r.Post("/complete-atom", h.HandleCompleteAtom)

		// Unified Quick Add (for Tasks tab)
		r.Post("/unified-add", h.HandleUnifiedAdd)
		r.Get("/partials/lists", h.HandleGetListsOptions)

		// Task detail/edit
		r.Get("/tasks/detail", h.HandleGetTaskDetail)
		r.Post("/tasks/update", h.HandleUpdateTask)

		// Bug reporting
		r.Get("/bugs", h.HandleGetBugs)
		r.Post("/bugs", h.HandleReportBug)
	})

	// Start server
	addr := ":" + cfg.Port
	srv := &http.Server{
		Addr:         addr,
		Handler:      r,
		ReadTimeout:  15 * time.Second,
		WriteTimeout: 15 * time.Second,
		IdleTimeout:  60 * time.Second,
	}

	// Graceful shutdown
	go func() {
		log.Printf("Starting server on http://localhost%s", addr)
		if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
			log.Fatalf("Server failed: %v", err)
		}
	}()

	// Wait for interrupt signal
	quit := make(chan os.Signal, 1)
	signal.Notify(quit, syscall.SIGINT, syscall.SIGTERM)
	<-quit

	log.Println("Shutting down server...")

	// Graceful shutdown with timeout
	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()

	if err := srv.Shutdown(ctx); err != nil {
		log.Fatalf("Server forced to shutdown: %v", err)
	}

	log.Println("Server exited")
}