package api

import (
	"encoding/json"
	"net/http"

	"github.com/google/uuid"
	"github.com/grassrootseconomics/cic-custodial/internal/custodial"

	"github.com/grassrootseconomics/cic-custodial/internal/tasker"
	"github.com/grassrootseconomics/cic-custodial/internal/tasker/task"
	"github.com/labstack/echo/v4"
)

// HandleSignTransfer route.
// POST: /api/sign/transfer
// JSON Body:
// from -> ETH address
// to -> ETH address
// voucherAddress -> ETH address
// amount -> int (6 d.p. precision)
// e.g. 1000000 = 1 VOUCHER
// Returns the task id.
func HandleSignTransfer(c echo.Context) error {
	var (
		cu  = c.Get("cu").(*custodial.Custodial)
		req struct {
			From           string `json:"from" validate:"required,eth_checksum"`
			To             string `json:"to" validate:"required,eth_checksum"`
			VoucherAddress string `json:"voucherAddress" validate:"required,eth_checksum"`
			Amount         uint64 `json:"amount" validate:"required"`
		}
	)

	if err := c.Bind(&req); err != nil {
		return NewBadRequestError(ErrInvalidJSON)
	}

	if err := c.Validate(req); err != nil {
		return err
	}

	accountActive, gasQuota, err := cu.PgStore.GetAccountStatusByAddress(c.Request().Context(), req.From)
	if err != nil {
		return err
	}

	if !accountActive {
		return c.JSON(http.StatusForbidden, ErrResp{
			Ok:      false,
			Message: "Account pending activation. Try again later.",
		})
	}

	if gasQuota < 1 {
		return c.JSON(http.StatusForbidden, ErrResp{
			Ok:      false,
			Message: "Out of gas, refill pending. Try again later.",
		})
	}

	trackingId := uuid.NewString()
	taskPayload, err := json.Marshal(task.TransferPayload{
		TrackingId:     trackingId,
		From:           req.From,
		To:             req.To,
		VoucherAddress: req.VoucherAddress,
		Amount:         req.Amount,
	})
	if err != nil {
		return err
	}

	_, err = cu.TaskerClient.CreateTask(
		c.Request().Context(),
		tasker.SignTransferTask,
		tasker.HighPriority,
		&tasker.Task{
			Id:      trackingId,
			Payload: taskPayload,
		},
	)
	if err != nil {
		return err
	}

	err = cu.PgStore.DecrGasQuota(c.Request().Context(), req.From)
	if err != nil {
		return err
	}

	return c.JSON(http.StatusOK, OkResp{
		Ok: true,
		Result: H{
			"trackingId": trackingId,
		},
	})
}