package handlers

import (
	"encoding/json"
	"errors"

	"Yimaru-Backend/internal/domain"
	"Yimaru-Backend/internal/services/chapa"

	"github.com/gofiber/fiber/v2"
)

// HandleChapaWebhook godoc
// @Summary Handle Chapa webhook
// @Description Processes payment notifications from Chapa (charge.success, etc.)
// @Tags payments
// @Accept json
// @Produce json
// @Success 200 {object} domain.Response
// @Failure 400 {object} domain.ErrorResponse
// @Router /api/v1/payments/webhook [post]
func (h *Handler) HandleChapaWebhook(c *fiber.Ctx) error {
	body := c.Body()
	signature := c.Get("x-chapa-signature")
	if signature == "" {
		signature = c.Get("chapa-signature")
	}

	if err := h.chapaSvc.VerifyWebhookSignature(body, signature); err != nil {
		h.logger.Error("Invalid Chapa webhook signature", "error", err)
		return c.Status(fiber.StatusUnauthorized).JSON(domain.ErrorResponse{
			Message: "Invalid webhook signature",
		})
	}

	var payload domain.ChapaWebhookPayload
	if err := json.Unmarshal(body, &payload); err != nil {
		return c.Status(fiber.StatusBadRequest).JSON(domain.ErrorResponse{
			Message: "Invalid webhook payload",
			Error:   err.Error(),
		})
	}

	if err := h.chapaSvc.ProcessPaymentWebhook(c.Context(), payload); err != nil {
		if errors.Is(err, chapa.ErrPaymentAlreadyPaid) {
			return c.JSON(domain.Response{Message: "Webhook already processed"})
		}
		h.logger.Error("Failed to process Chapa webhook", "error", err, "tx_ref", payload.TxRef)
		return c.Status(fiber.StatusInternalServerError).JSON(domain.ErrorResponse{
			Message: "Failed to process webhook",
			Error:   err.Error(),
		})
	}

	return c.JSON(domain.Response{
		Message: "Webhook processed successfully",
	})
}

// HandleChapaCallback godoc
// @Summary Chapa payment callback
// @Description Verifies payment after Chapa redirects to callback_url
// @Tags payments
// @Produce json
// @Param trx_ref query string false "Transaction reference"
// @Param ref_id query string false "Chapa reference ID"
// @Param status query string false "Payment status"
// @Success 200 {object} domain.Response
// @Router /api/v1/payments/chapa/callback [get]
func (h *Handler) HandleChapaCallback(c *fiber.Ctx) error {
	query := domain.ChapaCallbackQuery{
		TrxRef: c.Query("trx_ref"),
		RefID:  c.Query("ref_id"),
		Status: c.Query("status"),
	}
	if query.TrxRef == "" {
		query.TrxRef = c.Query("tx_ref")
	}

	if query.TrxRef == "" {
		return c.Status(fiber.StatusBadRequest).JSON(domain.ErrorResponse{
			Message: "trx_ref is required",
		})
	}

	if err := h.chapaSvc.ProcessCallback(c.Context(), query); err != nil {
		if errors.Is(err, chapa.ErrPaymentAlreadyPaid) {
			return c.JSON(domain.Response{Message: "Payment already processed"})
		}
		h.logger.Error("Failed to process Chapa callback", "error", err, "trx_ref", query.TrxRef)
		return c.Status(fiber.StatusInternalServerError).JSON(domain.ErrorResponse{
			Message: "Failed to process callback",
			Error:   err.Error(),
		})
	}

	return c.JSON(domain.Response{
		Message: "Callback processed successfully",
	})
}

// GetChapaPaymentMethods godoc
// @Summary Get Chapa payment methods
// @Description Returns payment methods available on Chapa checkout
// @Tags payments
// @Produce json
// @Success 200 {object} domain.Response
// @Router /api/v1/payments/methods [get]
func (h *Handler) GetChapaPaymentMethods(c *fiber.Ctx) error {
	return c.JSON(domain.Response{
		Message: "Payment methods retrieved successfully",
		Data:    h.chapaSvc.GetPaymentMethods(),
	})
}