package controllers

import (
	"fmt"
	"net/http"

	"github.com/getAlby/lndhub.go/lib"
	"github.com/getAlby/lndhub.go/lib/responses"
	"github.com/getAlby/lndhub.go/lib/service"
	"github.com/getsentry/sentry-go"
	"github.com/labstack/echo/v4"
	"github.com/lightningnetwork/lnd/lnrpc"
)

// KeySendController : Pay invoice controller struct
type KeySendController struct {
	svc *service.LndhubService
}

func NewKeySendController(svc *service.LndhubService) *KeySendController {
	return &KeySendController{svc: svc}
}

type KeySendRequestBody struct {
	Amount      int64  `json:"amount" validate:"required"`
	Destination string `json:"destination" validate:"required"`
	Memo        string `json:"memo" validate:"omitempty"`
}

type KeySendResponseBody struct {
	RHash              *lib.JavaScriptBuffer `json:"payment_hash,omitempty"`
	Amount             int64                 `json:"num_satoshis,omitempty"`
	Description        string                `json:"description,omitempty"`
	Destination        string                `json:"destination,omitempty"`
	DescriptionHashStr string                `json:"description_hash,omitempty"`
	PaymentError       string                `json:"payment_error,omitempty"`
	PaymentPreimage    *lib.JavaScriptBuffer `json:"payment_preimage,omitempty"`
	PaymentRoute       *service.Route        `json:"route,omitempty"`
}

// KeySend : Pay invoice Controller
func (controller *KeySendController) KeySend(c echo.Context) error {
	/*
		TODO: copy code from payinvoice.ctrl.go and modify where needed:
		- do not decode the payment request because there is no payment request.
		  Instead, construct the lnrpc.PaymentRequest manually from the KeySendRequestBody.
		- add outgoing invoice: same as payinvoice, make sure to set keysend=true
		- do a balance check: same as payinvoice, in fact do this before doing anything else
		- call svc.PayInvoice : same as payinvoice as long as keysend=true in Invoice
		- response will be slightly different due to lack of payment request
	*/

	userID := c.Get("UserID").(int64)
	reqBody := KeySendRequestBody{}
	if err := c.Bind(&reqBody); err != nil {
		c.Logger().Errorf("Failed to load payinvoice request body: %v", err)
		return c.JSON(http.StatusBadRequest, responses.BadArgumentsError)
	}

	if err := c.Validate(&reqBody); err != nil {
		c.Logger().Errorf("Invalid payinvoice request body: %v", err)
		return c.JSON(http.StatusBadRequest, responses.BadArgumentsError)
	}

	paymentRequest := &lnrpc.PayReq{
		Destination: reqBody.Destination,
		NumSatoshis: reqBody.Amount,
		Description: reqBody.Memo,
	}

	invoice, err := controller.svc.AddOutgoingInvoice(c.Request().Context(), userID, "", paymentRequest, true)
	if err != nil {
		return err
	}

	currentBalance, err := controller.svc.CurrentUserBalance(c.Request().Context(), userID)
	if err != nil {
		return err
	}

	if currentBalance < invoice.Amount {
		c.Logger().Errorf("User does not have enough balance invoice_id=%v user_id=%v balance=%v amount=%v", invoice.ID, userID, currentBalance, invoice.Amount)

		return c.JSON(http.StatusBadRequest, responses.NotEnoughBalanceError)
	}

	_, err = controller.svc.PayInvoice(c.Request().Context(), invoice)
	if err != nil {
		c.Logger().Errorf("Payment failed: %v", err)
		sentry.CaptureException(err)
		return c.JSON(http.StatusBadRequest, echo.Map{
			"error":   true,
			"code":    10,
			"message": fmt.Sprintf("Payment failed. Does the receiver have enough inbound capacity? (%v)", err),
		})
	}
	responseBody := &PayInvoiceResponseBody{}
	// responseBody.RHash = &lib.JavaScriptBuffer{Data: sendPaymentResponse.PaymentHash}
	// responseBody.PaymentRequest = paymentRequest
	// responseBody.PayReq = paymentRequest
	// responseBody.Amount = invoice.Amount
	// responseBody.Description = invoice.Memo
	// responseBody.DescriptionHashStr = invoice.DescriptionHash
	// responseBody.PaymentError = sendPaymentResponse.PaymentError
	// responseBody.PaymentPreimage = &lib.JavaScriptBuffer{Data: sendPaymentResponse.PaymentPreimage}
	// responseBody.PaymentRoute = sendPaymentResponse.PaymentRoute

	return c.JSON(http.StatusOK, responseBody)
}