package payment

import (
	"encoding/json"
	"fmt"
	"io"
	"log"
	"net/http"
	"os"

	"git.linuxforward.com/byom/byom-onboard/internal/platform/mailer"
	"github.com/gin-gonic/gin"
	"github.com/stripe/stripe-go/v81"
	"github.com/stripe/stripe-go/v81/account"
	portalsession "github.com/stripe/stripe-go/v81/billingportal/session"
	"github.com/stripe/stripe-go/v81/checkout/session"
	"github.com/stripe/stripe-go/v81/price"
	"github.com/stripe/stripe-go/v81/product"
	"github.com/stripe/stripe-go/v81/webhook"
)

type StripeHandler struct {
	domain         string
	endpointSecret string
	mailer         *mailer.Mailer
}

func NewStripeHandler(domain string, mailer *mailer.Mailer) (*StripeHandler, error) {
	apiKey := os.Getenv("STRIPE_SECRET_KEY")
	if apiKey == "" {
		return nil, fmt.Errorf("STRIPE_SECRET_KEY environment variable is not set")
	}

	endpointSecret := os.Getenv("STRIPE_WEBHOOK_SECRET")
	if endpointSecret == "" {
		return nil, fmt.Errorf("STRIPE_WEBHOOK_SECRET environment variable is not set")
	}

	stripe.Key = apiKey

	// Test connection by retrieving account information
	_, err := account.Get()
	if err != nil {
		return nil, fmt.Errorf("failed to connect to Stripe: %w", err)
	}

	return &StripeHandler{
		domain:         domain,
		endpointSecret: endpointSecret,
		mailer:         mailer,
	}, nil
}

func (h *StripeHandler) CreateCheckoutSession(c *gin.Context) {
	// Get email and priceID from request
	customerEmail := c.PostForm("email")
	priceID := c.PostForm("priceId")

	if customerEmail == "" {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Email is required"})
		return
	}

	if priceID == "" {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Price ID is required"})
		return
	}

	checkoutParams := &stripe.CheckoutSessionParams{
		Mode: stripe.String(string(stripe.CheckoutSessionModeSubscription)),
		LineItems: []*stripe.CheckoutSessionLineItemParams{
			{
				Price:    stripe.String(priceID),
				Quantity: stripe.Int64(1),
			},
		},
		SuccessURL:    stripe.String("https://byom.moooffle.com/payment/success?session_id={CHECKOUT_SESSION_ID}"),
		CancelURL:     stripe.String("https://byom.moooffle.com/payment/cancel"),
		CustomerEmail: stripe.String(customerEmail),
	}

	s, err := session.New(checkoutParams)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{
		"url":       s.URL,
		"sessionId": s.ID,
	})
}

func (h *StripeHandler) CreatePortalSession(c *gin.Context) {
	sessionID := c.PostForm("session_id")

	s, err := session.Get(sessionID, nil)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		log.Printf("session.Get: %v", err)
		return
	}

	params := &stripe.BillingPortalSessionParams{
		Customer:  stripe.String(s.Customer.ID),
		ReturnURL: stripe.String(h.domain),
	}
	ps, err := portalsession.New(params)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		log.Printf("ps.New: %v", err)
		return
	}

	c.Redirect(http.StatusSeeOther, ps.URL)
}

func (h *StripeHandler) HandleWebhook(c *gin.Context) {
	const MaxBodyBytes = int64(65536)
	bodyReader := http.MaxBytesReader(c.Writer, c.Request.Body, MaxBodyBytes)
	payload, err := io.ReadAll(bodyReader)
	if err != nil {
		log.Printf("[Webhook Debug] Error reading body: %v", err)
		c.JSON(http.StatusServiceUnavailable, gin.H{"error": "Service unavailable"})
		return
	}

	log.Printf("[Webhook Debug] Received payload: %s", string(payload))

	signatureHeader := c.Request.Header.Get("Stripe-Signature")
	log.Printf("[Webhook Debug] Stripe-Signature header: %s", signatureHeader)
	log.Printf("[Webhook Debug] Using endpoint secret: %s", h.endpointSecret)

	event, err := webhook.ConstructEvent(payload, signatureHeader, h.endpointSecret)
	if err != nil {
		log.Printf("[Webhook Debug] Signature verification failed: %v", err)
		log.Printf("[Webhook Debug] Headers received: %+v", c.Request.Header)
		c.JSON(http.StatusBadRequest, gin.H{"error": "Bad request"})
		return
	}

	log.Printf("[Webhook Debug] Event type received: %s", event.Type)
	log.Printf("[Webhook Debug] Event data: %s", string(event.Data.Raw))

	switch event.Type {
	case "customer.subscription.deleted":
		var subscription stripe.Subscription
		if err := json.Unmarshal(event.Data.Raw, &subscription); err != nil {
			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
			return
		}
		log.Printf("Subscription deleted for %s.", subscription.ID)

	case "customer.subscription.updated":
		var subscription stripe.Subscription
		if err := json.Unmarshal(event.Data.Raw, &subscription); err != nil {
			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
			return
		}
		log.Printf("Subscription updated for %s.", subscription.ID)

	case "customer.subscription.created":
		var subscription stripe.Subscription
		if err := json.Unmarshal(event.Data.Raw, &subscription); err != nil {
			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
			return
		}
		log.Printf("Subscription created for %s.", subscription.ID)

	case "checkout.session.completed":
		var session stripe.CheckoutSession
		if err := json.Unmarshal(event.Data.Raw, &session); err != nil {
			log.Printf("[Webhook Debug] Failed to parse session data: %v", err)
			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
			return
		}
		log.Printf("[Webhook Debug] Payment successful for session: %s", session.ID)

		customerEmail := session.CustomerEmail
		log.Printf("[Webhook Debug] Customer email: %s", customerEmail)

		if err := h.mailer.SendWelcomeEmail(customerEmail, &mailer.EmailData{
			Username:   customerEmail,
			WebAppURL:  fmt.Sprintf("http://test.byom.fr/login?email=%s", customerEmail),
			SetupGuide: "Votre espace de travail est prêt ! Connectez-vous pour commencer à utiliser Byom.",
		}); err != nil {
			log.Printf("[Webhook Debug] Failed to send welcome email: %v", err)
		}

	case "checkout.session.expired":
		var session stripe.CheckoutSession
		if err := json.Unmarshal(event.Data.Raw, &session); err != nil {
			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
			return
		}
		log.Printf("Payment session expired: %s", session.ID)
		// TODO: Gérer l'expiration de la session

	default:
		fmt.Fprintf(os.Stderr, "Unhandled event type: %s\n", event.Type)
	}

	c.JSON(http.StatusOK, gin.H{"status": "success"})
}

//implement this func

// const fetchPricingData = async () => {
// 	try {
// 		const response = await fetch('http://172.27.28.86:8080/api/v1/onboard/products');
// 		if (!response.ok) throw new Error('Failed to fetch products');
// 		const data = await response.json();

// 		// Transform API data to match UI requirements
// 		const transformedProducts = data.map(product => ({
// 			name: product.name,
// 			prices: {
// 				monthly: product.prices.monthly,
// 				yearly: product.prices.yearly,
// 				monthlyPriceId: product.prices.monthly_price_id,
// 				yearlyPriceId: product.prices.yearly_price_id
// 			},
// 			features: product.features,
// 			description: product.description,
// 			popular: product.metadata?.is_popular === "true",
// 			maxUsers: product.max_users,
// 			storageLimit: product.storage_limit,
// 			apiRateLimit: product.api_rate_limit,
// 			supportTier: product.support_tier,
// 			customDomain: product.custom_domain
// 		}));

// 		setPricingData(transformedProducts);
// 	} catch (error) {
// 		console.error('Error fetching products:', error);
// 		// Set fallback pricing data
// 		setPricingData([
// 			{
// 				name: 'Starter',
// 				prices: { monthly: 29, yearly: 290 },
// 				features: [
// 					'Basic AI trend analysis',
// 					'25 AI image generations/month',
// 					'Basic analytics dashboard',
// 					'Content calendar',
// 					'Email support',
// 					'Single user'
// 				],
// 			},
// 			// ... other fallback plans
// 		]);
// 	} finally {
// 		setIsLoading(false);
// 	}
// };

func (h *StripeHandler) GetProducts(c *gin.Context) {
	params := &stripe.ProductListParams{
		Active: stripe.Bool(true),
	}
	products := product.List(params)

	var response []ProductResponse

	for products.Next() {
		p := products.Product()

		// Parse product metadata
		var metadata ProductMetadata
		if metadataJSON, ok := p.Metadata["product_config"]; ok {
			if err := json.Unmarshal([]byte(metadataJSON), &metadata); err != nil {
				log.Printf("Error parsing metadata for product %s: %v", p.ID, err)
				continue
			}
		}

		// Fetch prices (rest of the price fetching logic remains the same)
		priceParams := &stripe.PriceListParams{
			Product: stripe.String(p.ID),
			Active:  stripe.Bool(true),
		}
		prices := price.List(priceParams)

		var monthlyPrice, yearlyPrice int64
		var monthlyPriceID, yearlyPriceID string

		for prices.Next() {
			pr := prices.Price()
			if pr.Recurring.Interval == "month" {
				monthlyPrice = pr.UnitAmount / 100
				monthlyPriceID = pr.ID
			}
			if pr.Recurring.Interval == "year" {
				yearlyPrice = pr.UnitAmount / 100
				yearlyPriceID = pr.ID
			}
		}

		response = append(response, ProductResponse{
			ID:          p.ID,
			Name:        p.Name,
			Description: metadata.Description,
			Prices: Prices{
				Monthly:        monthlyPrice,
				Yearly:         yearlyPrice,
				MonthlyPriceID: monthlyPriceID,
				YearlyPriceID:  yearlyPriceID,
			},
			Features:     metadata.Features,
			MaxUsers:     metadata.MaxUsers,
			StorageLimit: metadata.StorageLimit,
			ApiRateLimit: metadata.ApiRateLimit,
			SupportTier:  metadata.SupportTier,
			CustomDomain: metadata.CustomDomain,
		})
	}

	c.JSON(200, response)
}

type ProductMetadata struct {
	Description  string   `json:"description"`
	Features     []string `json:"features"`
	MaxUsers     int      `json:"max_users"`
	StorageLimit string   `json:"storage_limit"`
	ApiRateLimit int      `json:"api_rate_limit"`
	SupportTier  string   `json:"support_tier"`
	CustomDomain bool     `json:"custom_domain"`
}

type ProductResponse struct {
	ID           string                 `json:"id"`
	Name         string                 `json:"name"`
	Description  string                 `json:"description"`
	Prices       Prices                 `json:"prices"`
	Features     []string               `json:"features"`
	MaxUsers     int                    `json:"max_users"`
	Metadata     map[string]interface{} `json:"metadata"`
	StorageLimit string                 `json:"storage_limit"`
	ApiRateLimit int                    `json:"api_rate_limit"`
	SupportTier  string                 `json:"support_tier"`
	CustomDomain bool                   `json:"custom_domain"`
}

type Prices struct {
	Monthly        int64  `json:"monthly"`
	Yearly         int64  `json:"yearly"`
	MonthlyPriceID string `json:"monthly_price_id"`
	YearlyPriceID  string `json:"yearly_price_id"`
}