package cnvrt

import (
	"context"
	cnvrtv1 "github.com/netscrawler/protoss/gen/go/changeAPI"
	"google.golang.org/grpc"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/status"
	"log/slog"
	"os"
)

type response struct {
	ConvertedAmount   uint32
	Rate              float32
	ConvertedAmo      uint32
	ConvertedCurrency string
}

type Converter interface {
	Convert(ctx context.Context,
		amount uint32,
		targetCurrency string,
	) (convertedAmount uint32, rate float32, err error)
}

type serverAPI struct {
	cnvrtv1.UnimplementedConverterServer
	convert Converter
}

func Register(gRPC *grpc.Server, convert Converter) {
	cnvrtv1.RegisterConverterServer(gRPC, &serverAPI{convert: convert})
}

func (s *serverAPI) Convert(
	ctx context.Context,
	req *cnvrtv1.ConvertRequest) (
	*cnvrtv1.ConvertResponse, error) {

	log := setupLogger()
	log.Info("convertationRequest", slog.Any("req", req))

	if !isValidCurrency(req.GetTargetCurrency()) {
		return nil, status.Error(codes.InvalidArgument, "Invalid target currency")
	}

	convertedAmount, rate, err := s.convert.Convert(ctx, req.GetAmount(), req.GetTargetCurrency())
	baseAmount := req.GetAmount()
	convertedAmo := convertedAmount
	convertedCurrency := req.GetTargetCurrency()
	Rate := rate
	r := response{baseAmount, rate, convertedAmo, convertedCurrency}
	log.Info("ConvertationResponse", slog.Any("res", r))

	if err != nil {
		//todo error handler
		return nil, status.Error(codes.Internal, "Internal error")
	}
	return &cnvrtv1.ConvertResponse{
		BaseAmount:        baseAmount,
		ConvertedAmount:   convertedAmo,
		ConvertedCurrency: convertedCurrency,
		Rate:              Rate,
	}, nil
}

func isValidCurrency(currency string) bool {

	currencies := map[string]bool{
		"AUD": true, "GBP": true, "BYR": true, "DKK": true, "USD": true, "EUR": true,
		"ISK": true, "KZT": true, "CAD": true, "NOK": true, "XDR": true, "SGD": true,
		"TRL": true, "UAH": true, "SEK": true, "CHF": true, "JPY": true,
	}
	if currencies[currency] {
		return true
	}
	return false
}

func setupLogger() *slog.Logger {
	var log *slog.Logger
	log = slog.New(
		slog.NewJSONHandler(os.Stdout, &slog.HandlerOptions{Level: slog.LevelInfo}),
	)
	return log
}