package mercedes

import (
	"fmt"

	"github.com/evcc-io/evcc/util"
	"github.com/evcc-io/evcc/util/request"
	"github.com/evcc-io/evcc/util/transport"
	protos "github.com/evcc-io/evcc/vehicle/mercedes/pb"
	"golang.org/x/oauth2"
	"google.golang.org/protobuf/proto"
)

// API is an api.Vehicle implementation for Mercedes-Benz cars
type API struct {
	region string
	log    *util.Logger
	*request.Helper
}

func NewAPI(log *util.Logger, identity *Identity) *API {
	client := request.NewHelper(log)

	client.Transport = &transport.Decorator{
		Base: &oauth2.Transport{
			Source: identity,
			Base:   client.Transport,
		},
		Decorator: transport.DecorateHeaders(mbheaders(false, identity.region)),
	}

	return &API{
		Helper: client,
		region: identity.region,
		log:    log,
	}
}

func (v *API) Vehicles() ([]string, error) {
	var res VehiclesResponse

	url := fmt.Sprintf("%s/v2/vehicles", getBffUri(v.region))

	err := v.GetJSON(url, &res)
	if err != nil {
		return nil, err
	}

	var vehicles []string
	for _, v := range res.AssignedVehicles {
		if len(v.Vin) > 0 {
			vehicles = append(vehicles, v.Vin)
		} else {
			vehicles = append(vehicles, v.Fin)
		}
	}

	return vehicles, err
}

func (v *API) Status(vin string) (StatusResponse, error) {
	var res StatusResponse

	uri := fmt.Sprintf("%s/v1/vehicle/%s/vehicleattributes", getWidgetUri(v.region), vin)

	data, err := v.GetBody(uri)
	if err != nil {
		return res, err
	}

	var message protos.VEPUpdate
	if err = proto.Unmarshal(data, &message); err != nil {
		return res, err
	}

	if val, ok := message.Attributes["odo"]; ok {
		res.VehicleInfo.Odometer.Value = int(val.GetIntValue())
		res.VehicleInfo.Odometer.Unit = val.GetDistanceUnit().String()
	}

	if val, ok := message.Attributes["soc"]; ok {
		res.EvInfo.Battery.StateOfCharge = float64(val.GetIntValue())
	}

	if val, ok := message.Attributes["rangeelectric"]; ok {
		res.EvInfo.Battery.DistanceToEmpty.Value = int(val.GetIntValue())
		res.EvInfo.Battery.DistanceToEmpty.Unit = val.GetDistanceUnit().String()
	}

	if val, ok := message.Attributes["endofchargetime"]; ok {
		res.EvInfo.Battery.EndOfChargeTime = int(val.GetIntValue())
	}

	if val, ok := message.Attributes["chargingstatus"]; ok {
		res.EvInfo.Battery.ChargingStatus = int(val.GetIntValue())
	} else {
		res.EvInfo.Battery.ChargingStatus = 3
	}

	if val, ok := message.Attributes["maxSoc"]; ok && val != nil {
		res.EvInfo.Battery.SocLimit = int(val.GetIntValue())
	}

	if val, ok := message.Attributes["selectedChargeProgram"]; ok && val != nil {
		selectedChargeProgram := val.GetIntValue()
		res.EvInfo.Battery.SelectedChargeProgram = int(selectedChargeProgram)

		if cps, ok := message.Attributes["chargePrograms"]; ok && cps != nil {
			if cpVal := cps.GetChargeProgramsValue(); cpVal != nil && res.EvInfo.Battery.SelectedChargeProgram < len(cpVal.ChargeProgramParameters) {
				if chargeProgramParam := cpVal.ChargeProgramParameters[res.EvInfo.Battery.SelectedChargeProgram]; chargeProgramParam != nil {
					res.EvInfo.Battery.SocLimit = int(chargeProgramParam.GetMaxSoc())
				}
			}
		}
	}

	// There are two attributes for the proconditioning status, precondNow and precondActive
	if val, ok := message.Attributes["precondNow"]; ok {
		res.Preconditioning.Active = val.GetBoolValue()
	}
	if !res.Preconditioning.Active {
		if val, ok := message.Attributes["precondActive"]; ok {
			res.Preconditioning.Active = val.GetBoolValue()
		}
	}

	return res, err
}