package router

import (
	"net/http"
	"time"

	"github.com/gin-contrib/cors"
	"github.com/gin-gonic/gin"
	"gorm.io/gorm"

	"github.com/treytartt/mycrib-api/internal/config"
	"github.com/treytartt/mycrib-api/internal/handlers"
	"github.com/treytartt/mycrib-api/internal/middleware"
	"github.com/treytartt/mycrib-api/internal/push"
	"github.com/treytartt/mycrib-api/internal/repositories"
	"github.com/treytartt/mycrib-api/internal/services"
	"github.com/treytartt/mycrib-api/pkg/utils"
)

const Version = "2.0.0"

// Dependencies holds all dependencies needed by the router
type Dependencies struct {
	DB           *gorm.DB
	Cache        *services.CacheService
	Config       *config.Config
	EmailService *services.EmailService
	PushClient   interface{} // *push.GorushClient - optional
}

// SetupRouter creates and configures the Gin router
func SetupRouter(deps *Dependencies) *gin.Engine {
	cfg := deps.Config

	// Set Gin mode based on debug setting
	if cfg.Server.Debug {
		gin.SetMode(gin.DebugMode)
	} else {
		gin.SetMode(gin.ReleaseMode)
	}

	r := gin.New()

	// Global middleware
	r.Use(utils.GinRecovery())
	r.Use(utils.GinLogger())
	r.Use(corsMiddleware(cfg))

	// Health check endpoint (no auth required)
	r.GET("/api/health/", healthCheck)

	// Initialize repositories
	userRepo := repositories.NewUserRepository(deps.DB)
	residenceRepo := repositories.NewResidenceRepository(deps.DB)
	taskRepo := repositories.NewTaskRepository(deps.DB)
	contractorRepo := repositories.NewContractorRepository(deps.DB)
	documentRepo := repositories.NewDocumentRepository(deps.DB)
	notificationRepo := repositories.NewNotificationRepository(deps.DB)
	subscriptionRepo := repositories.NewSubscriptionRepository(deps.DB)

	// Initialize push client (optional)
	var gorushClient *push.GorushClient
	if deps.PushClient != nil {
		if gc, ok := deps.PushClient.(*push.GorushClient); ok {
			gorushClient = gc
		}
	}

	// Initialize services
	authService := services.NewAuthService(userRepo, cfg)
	residenceService := services.NewResidenceService(residenceRepo, userRepo, cfg)
	taskService := services.NewTaskService(taskRepo, residenceRepo)
	contractorService := services.NewContractorService(contractorRepo, residenceRepo)
	documentService := services.NewDocumentService(documentRepo, residenceRepo)
	notificationService := services.NewNotificationService(notificationRepo, gorushClient)
	subscriptionService := services.NewSubscriptionService(subscriptionRepo, residenceRepo, taskRepo, contractorRepo, documentRepo)

	// Initialize middleware
	authMiddleware := middleware.NewAuthMiddleware(deps.DB, deps.Cache)

	// Initialize handlers
	authHandler := handlers.NewAuthHandler(authService, deps.EmailService, deps.Cache)
	residenceHandler := handlers.NewResidenceHandler(residenceService)
	taskHandler := handlers.NewTaskHandler(taskService)
	contractorHandler := handlers.NewContractorHandler(contractorService)
	documentHandler := handlers.NewDocumentHandler(documentService)
	notificationHandler := handlers.NewNotificationHandler(notificationService)
	subscriptionHandler := handlers.NewSubscriptionHandler(subscriptionService)

	// API group
	api := r.Group("/api")
	{
		// Public auth routes (no auth required)
		setupPublicAuthRoutes(api, authHandler)

		// Public data routes (no auth required)
		setupPublicDataRoutes(api, residenceHandler, taskHandler, contractorHandler)

		// Protected routes (auth required)
		protected := api.Group("")
		protected.Use(authMiddleware.TokenAuth())
		{
			setupProtectedAuthRoutes(protected, authHandler)
			setupResidenceRoutes(protected, residenceHandler)
			setupTaskRoutes(protected, taskHandler)
			setupContractorRoutes(protected, contractorHandler)
			setupDocumentRoutes(protected, documentHandler)
			setupNotificationRoutes(protected, notificationHandler)
			setupSubscriptionRoutes(protected, subscriptionHandler)
			setupUserRoutes(protected)
		}
	}

	return r
}

// corsMiddleware configures CORS
func corsMiddleware(cfg *config.Config) gin.HandlerFunc {
	corsConfig := cors.Config{
		AllowMethods:     []string{"GET", "POST", "PUT", "PATCH", "DELETE", "OPTIONS"},
		AllowHeaders:     []string{"Origin", "Content-Type", "Accept", "Authorization"},
		ExposeHeaders:    []string{"Content-Length"},
		AllowCredentials: true,
		MaxAge:           12 * time.Hour,
	}

	// In debug mode, allow all origins; otherwise use configured hosts
	if cfg.Server.Debug {
		corsConfig.AllowAllOrigins = true
	} else {
		corsConfig.AllowOrigins = cfg.Server.AllowedHosts
	}

	return cors.New(corsConfig)
}

// healthCheck returns API health status
func healthCheck(c *gin.Context) {
	c.JSON(http.StatusOK, gin.H{
		"status":    "healthy",
		"version":   Version,
		"framework": "Gin",
		"timestamp": time.Now().UTC().Format(time.RFC3339),
	})
}

// setupPublicAuthRoutes configures public authentication routes
func setupPublicAuthRoutes(api *gin.RouterGroup, authHandler *handlers.AuthHandler) {
	auth := api.Group("/auth")
	{
		auth.POST("/login/", authHandler.Login)
		auth.POST("/register/", authHandler.Register)
		auth.POST("/forgot-password/", authHandler.ForgotPassword)
		auth.POST("/verify-reset-code/", authHandler.VerifyResetCode)
		auth.POST("/reset-password/", authHandler.ResetPassword)
	}
}

// setupProtectedAuthRoutes configures protected authentication routes
func setupProtectedAuthRoutes(api *gin.RouterGroup, authHandler *handlers.AuthHandler) {
	auth := api.Group("/auth")
	{
		auth.POST("/logout/", authHandler.Logout)
		auth.GET("/me/", authHandler.CurrentUser)
		auth.PUT("/profile/", authHandler.UpdateProfile)
		auth.PATCH("/profile/", authHandler.UpdateProfile)
		auth.POST("/verify-email/", authHandler.VerifyEmail)
		auth.POST("/resend-verification/", authHandler.ResendVerification)
	}
}

// setupPublicDataRoutes configures public data routes (lookups, static data)
func setupPublicDataRoutes(api *gin.RouterGroup, residenceHandler *handlers.ResidenceHandler, taskHandler *handlers.TaskHandler, contractorHandler *handlers.ContractorHandler) {
	// Static data routes (public, cached)
	staticData := api.Group("/static_data")
	{
		staticData.GET("/", placeholderHandler("get-static-data"))
		staticData.POST("/refresh/", placeholderHandler("refresh-static-data"))
	}

	// Lookup routes (public)
	api.GET("/residences/types/", residenceHandler.GetResidenceTypes)
	api.GET("/tasks/categories/", taskHandler.GetCategories)
	api.GET("/tasks/priorities/", taskHandler.GetPriorities)
	api.GET("/tasks/frequencies/", taskHandler.GetFrequencies)
	api.GET("/tasks/statuses/", taskHandler.GetStatuses)
	api.GET("/contractors/specialties/", contractorHandler.GetSpecialties)
}

// setupResidenceRoutes configures residence routes
func setupResidenceRoutes(api *gin.RouterGroup, residenceHandler *handlers.ResidenceHandler) {
	residences := api.Group("/residences")
	{
		residences.GET("/", residenceHandler.ListResidences)
		residences.POST("/", residenceHandler.CreateResidence)
		residences.GET("/my-residences/", residenceHandler.GetMyResidences)
		residences.POST("/join-with-code/", residenceHandler.JoinWithCode)

		residences.GET("/:id/", residenceHandler.GetResidence)
		residences.PUT("/:id/", residenceHandler.UpdateResidence)
		residences.PATCH("/:id/", residenceHandler.UpdateResidence)
		residences.DELETE("/:id/", residenceHandler.DeleteResidence)

		residences.POST("/:id/generate-share-code/", residenceHandler.GenerateShareCode)
		residences.POST("/:id/generate-tasks-report/", placeholderHandler("generate-tasks-report"))
		residences.GET("/:id/users/", residenceHandler.GetResidenceUsers)
		residences.DELETE("/:id/users/:user_id/", residenceHandler.RemoveResidenceUser)
	}
}

// setupTaskRoutes configures task routes
func setupTaskRoutes(api *gin.RouterGroup, taskHandler *handlers.TaskHandler) {
	tasks := api.Group("/tasks")
	{
		tasks.GET("/", taskHandler.ListTasks)
		tasks.POST("/", taskHandler.CreateTask)
		tasks.GET("/by-residence/:residence_id/", taskHandler.GetTasksByResidence)

		tasks.GET("/:id/", taskHandler.GetTask)
		tasks.PUT("/:id/", taskHandler.UpdateTask)
		tasks.PATCH("/:id/", taskHandler.UpdateTask)
		tasks.DELETE("/:id/", taskHandler.DeleteTask)

		tasks.POST("/:id/mark-in-progress/", taskHandler.MarkInProgress)
		tasks.POST("/:id/cancel/", taskHandler.CancelTask)
		tasks.POST("/:id/uncancel/", taskHandler.UncancelTask)
		tasks.POST("/:id/archive/", taskHandler.ArchiveTask)
		tasks.POST("/:id/unarchive/", taskHandler.UnarchiveTask)
	}

	// Task Completions
	completions := api.Group("/task-completions")
	{
		completions.GET("/", taskHandler.ListCompletions)
		completions.POST("/", taskHandler.CreateCompletion)
		completions.GET("/:id/", taskHandler.GetCompletion)
		completions.DELETE("/:id/", taskHandler.DeleteCompletion)
	}
}

// setupContractorRoutes configures contractor routes
func setupContractorRoutes(api *gin.RouterGroup, contractorHandler *handlers.ContractorHandler) {
	contractors := api.Group("/contractors")
	{
		contractors.GET("/", contractorHandler.ListContractors)
		contractors.POST("/", contractorHandler.CreateContractor)
		contractors.GET("/:id/", contractorHandler.GetContractor)
		contractors.PUT("/:id/", contractorHandler.UpdateContractor)
		contractors.PATCH("/:id/", contractorHandler.UpdateContractor)
		contractors.DELETE("/:id/", contractorHandler.DeleteContractor)
		contractors.POST("/:id/toggle-favorite/", contractorHandler.ToggleFavorite)
		contractors.GET("/:id/tasks/", contractorHandler.GetContractorTasks)
	}
}

// setupDocumentRoutes configures document routes
func setupDocumentRoutes(api *gin.RouterGroup, documentHandler *handlers.DocumentHandler) {
	documents := api.Group("/documents")
	{
		documents.GET("/", documentHandler.ListDocuments)
		documents.POST("/", documentHandler.CreateDocument)
		documents.GET("/warranties/", documentHandler.ListWarranties)
		documents.GET("/:id/", documentHandler.GetDocument)
		documents.PUT("/:id/", documentHandler.UpdateDocument)
		documents.PATCH("/:id/", documentHandler.UpdateDocument)
		documents.DELETE("/:id/", documentHandler.DeleteDocument)
		documents.POST("/:id/activate/", documentHandler.ActivateDocument)
		documents.POST("/:id/deactivate/", documentHandler.DeactivateDocument)
	}
}

// setupNotificationRoutes configures notification routes
func setupNotificationRoutes(api *gin.RouterGroup, notificationHandler *handlers.NotificationHandler) {
	notifications := api.Group("/notifications")
	{
		notifications.GET("/", notificationHandler.ListNotifications)
		notifications.GET("/unread-count/", notificationHandler.GetUnreadCount)
		notifications.POST("/mark-all-read/", notificationHandler.MarkAllAsRead)
		notifications.POST("/:id/read/", notificationHandler.MarkAsRead)

		notifications.POST("/devices/", notificationHandler.RegisterDevice)
		notifications.GET("/devices/", notificationHandler.ListDevices)
		notifications.DELETE("/devices/:id/", notificationHandler.DeleteDevice)

		notifications.GET("/preferences/", notificationHandler.GetPreferences)
		notifications.PUT("/preferences/", notificationHandler.UpdatePreferences)
		notifications.PATCH("/preferences/", notificationHandler.UpdatePreferences)
	}
}

// setupSubscriptionRoutes configures subscription routes
func setupSubscriptionRoutes(api *gin.RouterGroup, subscriptionHandler *handlers.SubscriptionHandler) {
	subscription := api.Group("/subscription")
	{
		subscription.GET("/", subscriptionHandler.GetSubscription)
		subscription.GET("/status/", subscriptionHandler.GetSubscriptionStatus)
		subscription.GET("/upgrade-trigger/:key/", subscriptionHandler.GetUpgradeTrigger)
		subscription.GET("/features/", subscriptionHandler.GetFeatureBenefits)
		subscription.GET("/promotions/", subscriptionHandler.GetPromotions)
		subscription.POST("/purchase/", subscriptionHandler.ProcessPurchase)
		subscription.POST("/cancel/", subscriptionHandler.CancelSubscription)
		subscription.POST("/restore/", subscriptionHandler.RestoreSubscription)
	}
}

// setupUserRoutes configures user routes
func setupUserRoutes(api *gin.RouterGroup) {
	users := api.Group("/users")
	{
		users.GET("/", placeholderHandler("list-users"))
		users.GET("/:id/", placeholderHandler("get-user"))
		users.GET("/profiles/", placeholderHandler("list-profiles"))
	}
}

// placeholderHandler returns a handler that indicates an endpoint is not yet implemented
func placeholderHandler(name string) gin.HandlerFunc {
	return func(c *gin.Context) {
		c.JSON(http.StatusNotImplemented, gin.H{
			"error":    "Endpoint not yet implemented",
			"endpoint": name,
			"message":  "This endpoint is planned for future phases",
		})
	}
}