package main

import (
	"context"
	"os"
	"os/signal"
	"syscall"
	"time"

	"github.com/hibiken/asynq"
	"github.com/rs/zerolog/log"

	"github.com/treytartt/casera-api/internal/config"
	"github.com/treytartt/casera-api/internal/database"
	"github.com/treytartt/casera-api/internal/push"
	"github.com/treytartt/casera-api/internal/services"
	"github.com/treytartt/casera-api/internal/worker/jobs"
	"github.com/treytartt/casera-api/pkg/utils"
)

func main() {
	// Initialize logger
	utils.InitLogger(true)

	// Load configuration
	cfg, err := config.Load()
	if err != nil {
		log.Fatal().Err(err).Msg("Failed to load configuration")
	}

	// Initialize database
	db, err := database.Connect(&cfg.Database, cfg.Server.Debug)
	if err != nil {
		log.Fatal().Err(err).Msg("Failed to connect to database")
	}
	log.Info().Msg("Connected to database")

	// Get underlying *sql.DB for cleanup
	sqlDB, _ := db.DB()
	defer sqlDB.Close()

	// Initialize push client (APNs + FCM)
	var pushClient *push.Client
	pushClient, err = push.NewClient(&cfg.Push)
	if err != nil {
		log.Warn().Err(err).Msg("Failed to initialize push client - push notifications disabled")
	} else {
		log.Info().
			Bool("ios_enabled", pushClient.IsIOSEnabled()).
			Bool("android_enabled", pushClient.IsAndroidEnabled()).
			Msg("Push notification client initialized")
	}

	// Initialize email service (optional)
	var emailService *services.EmailService
	if cfg.Email.Host != "" {
		emailService = services.NewEmailService(&cfg.Email)
		log.Info().Str("host", cfg.Email.Host).Msg("Email service initialized")
	}

	// Parse Redis URL for Asynq
	redisOpt, err := asynq.ParseRedisURI(cfg.Redis.URL)
	if err != nil {
		log.Fatal().Err(err).Msg("Failed to parse Redis URL")
	}

	// Create Asynq server
	srv := asynq.NewServer(
		redisOpt,
		asynq.Config{
			Concurrency: 10,
			Queues: map[string]int{
				"critical": 6,
				"default":  3,
				"low":      1,
			},
			ErrorHandler: asynq.ErrorHandlerFunc(func(ctx context.Context, task *asynq.Task, err error) {
				log.Error().
					Err(err).
					Str("type", task.Type()).
					Bytes("payload", task.Payload()).
					Msg("Task processing failed")
			}),
		},
	)

	// Create job handler
	jobHandler := jobs.NewHandler(db, pushClient, emailService, cfg)

	// Create Asynq mux and register handlers
	mux := asynq.NewServeMux()
	mux.HandleFunc(jobs.TypeTaskReminder, jobHandler.HandleTaskReminder)
	mux.HandleFunc(jobs.TypeOverdueReminder, jobHandler.HandleOverdueReminder)
	mux.HandleFunc(jobs.TypeDailyDigest, jobHandler.HandleDailyDigest)
	mux.HandleFunc(jobs.TypeSendEmail, jobHandler.HandleSendEmail)
	mux.HandleFunc(jobs.TypeSendPush, jobHandler.HandleSendPush)

	// Start scheduler for periodic tasks
	scheduler := asynq.NewScheduler(redisOpt, nil)

	// Schedule task reminder notifications
	reminderCron := formatCron(cfg.Worker.TaskReminderHour, cfg.Worker.TaskReminderMinute)
	if _, err := scheduler.Register(reminderCron, asynq.NewTask(jobs.TypeTaskReminder, nil)); err != nil {
		log.Fatal().Err(err).Msg("Failed to register task reminder job")
	}
	log.Info().Str("cron", reminderCron).Msg("Registered task reminder job")

	// Schedule overdue reminder at 9 AM UTC
	overdueCron := formatCron(cfg.Worker.OverdueReminderHour, 0)
	if _, err := scheduler.Register(overdueCron, asynq.NewTask(jobs.TypeOverdueReminder, nil)); err != nil {
		log.Fatal().Err(err).Msg("Failed to register overdue reminder job")
	}
	log.Info().Str("cron", overdueCron).Msg("Registered overdue reminder job")

	// Schedule daily digest at 11 AM UTC
	dailyCron := formatCron(cfg.Worker.DailyNotifHour, 0)
	if _, err := scheduler.Register(dailyCron, asynq.NewTask(jobs.TypeDailyDigest, nil)); err != nil {
		log.Fatal().Err(err).Msg("Failed to register daily digest job")
	}
	log.Info().Str("cron", dailyCron).Msg("Registered daily digest job")

	// Handle graceful shutdown
	quit := make(chan os.Signal, 1)
	signal.Notify(quit, syscall.SIGINT, syscall.SIGTERM)

	// Start scheduler in goroutine
	go func() {
		if err := scheduler.Run(); err != nil {
			log.Fatal().Err(err).Msg("Failed to start scheduler")
		}
	}()

	// Start worker server in goroutine
	go func() {
		log.Info().Msg("Starting worker server...")
		if err := srv.Run(mux); err != nil {
			log.Fatal().Err(err).Msg("Failed to start worker server")
		}
	}()

	<-quit
	log.Info().Msg("Shutting down worker...")

	// Graceful shutdown
	srv.Shutdown()
	scheduler.Shutdown()

	log.Info().Msg("Worker stopped")
}

// formatCron creates a cron expression for a specific hour and minute (UTC)
func formatCron(hour, minute int) string {
	return time.Date(0, 1, 1, hour, minute, 0, 0, time.UTC).Format("4 15 * * *")
}