package adxcg

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

	"github.com/prebid/openrtb/v20/openrtb2"
	"github.com/prebid/prebid-server/v4/adapters"
	"github.com/prebid/prebid-server/v4/config"
	"github.com/prebid/prebid-server/v4/errortypes"
	"github.com/prebid/prebid-server/v4/openrtb_ext"
	"github.com/prebid/prebid-server/v4/util/jsonutil"
)

// Builder builds a new instance of the Adxcg adapter for the given bidder with the given config.
func Builder(bidderName openrtb_ext.BidderName, config config.Adapter, server config.Server) (adapters.Bidder, error) {
	bidder := &adapter{
		endpoint: config.Endpoint,
	}
	return bidder, nil
}

type adapter struct {
	endpoint string
}

// MakeRequests prepares the HTTP requests which should be made to fetch bids.
func (adapter *adapter) MakeRequests(
	openRTBRequest *openrtb2.BidRequest,
	reqInfo *adapters.ExtraRequestInfo,
) (
	requestsToBidder []*adapters.RequestData,
	errs []error,
) {
	openRTBRequestJSON, err := json.Marshal(openRTBRequest)
	if err != nil {
		errs = append(errs, err)
		return nil, errs
	}

	headers := http.Header{}
	headers.Add("Content-Type", "application/json;charset=utf-8")
	requestToBidder := &adapters.RequestData{
		Method:  "POST",
		Uri:     adapter.endpoint,
		Body:    openRTBRequestJSON,
		Headers: headers,
		ImpIDs:  openrtb_ext.GetImpIDs(openRTBRequest.Imp),
	}
	requestsToBidder = append(requestsToBidder, requestToBidder)

	return requestsToBidder, errs
}

const unexpectedStatusCodeFormat = "Unexpected status code: %d. Run with request.debug = 1 for more info"

// MakeBids unpacks the server's response into Bids.
func (adapter *adapter) MakeBids(
	openRTBRequest *openrtb2.BidRequest,
	requestToBidder *adapters.RequestData,
	bidderRawResponse *adapters.ResponseData,
) (
	bidderResponse *adapters.BidderResponse,
	errs []error,
) {
	switch bidderRawResponse.StatusCode {
	case http.StatusOK:
		break
	case http.StatusNoContent:
		return nil, nil
	case http.StatusBadRequest:
		err := &errortypes.BadInput{
			Message: fmt.Sprintf(unexpectedStatusCodeFormat, bidderRawResponse.StatusCode),
		}
		return nil, []error{err}
	default:
		err := &errortypes.BadServerResponse{
			Message: fmt.Sprintf(unexpectedStatusCodeFormat, bidderRawResponse.StatusCode),
		}
		return nil, []error{err}
	}

	var openRTBBidderResponse openrtb2.BidResponse
	if err := jsonutil.Unmarshal(bidderRawResponse.Body, &openRTBBidderResponse); err != nil {
		return nil, []error{err}
	}

	bidderResponse = adapters.NewBidderResponseWithBidsCapacity(len(openRTBRequest.Imp))
	bidderResponse.Currency = openRTBBidderResponse.Cur
	var typedBid *adapters.TypedBid
	for _, seatBid := range openRTBBidderResponse.SeatBid {
		for _, bid := range seatBid.Bid {
			activeBid := bid
			bidType, err := getReturnTypeFromMtypeForImp(activeBid.MType)
			if err != nil {
				errs = append(errs, err)
				continue
			}

			typedBid = &adapters.TypedBid{Bid: &activeBid, BidType: bidType}
			bidderResponse.Bids = append(bidderResponse.Bids, typedBid)
		}
	}

	return bidderResponse, nil

}

func getReturnTypeFromMtypeForImp(mType openrtb2.MarkupType) (openrtb_ext.BidType, error) {
	switch mType {
	case openrtb2.MarkupBanner:
		return openrtb_ext.BidTypeBanner, nil
	case openrtb2.MarkupVideo:
		return openrtb_ext.BidTypeVideo, nil
	case openrtb2.MarkupNative:
		return openrtb_ext.BidTypeNative, nil
	case openrtb2.MarkupAudio:
		return openrtb_ext.BidTypeAudio, nil
	default:
		return "", &errortypes.BadServerResponse{Message: "Unsupported return type"}
	}
}