package nativo

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/openrtb_ext"
)

type adapter struct {
	endpoint string
}

// Builder builds a new instance of the Nativo 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
}

func (a *adapter) MakeRequests(request *openrtb2.BidRequest, _ *adapters.ExtraRequestInfo) ([]*adapters.RequestData, []error) {
	requestJSON, err := json.Marshal(request)
	if err != nil {
		return nil, []error{err}
	}

	headers := http.Header{}
	headers.Add("Content-Type", "application/json;charset=utf-8")

	requestData := &adapters.RequestData{
		Method:  "POST",
		Uri:     a.endpoint,
		Body:    requestJSON,
		Headers: headers,
		ImpIDs:  openrtb_ext.GetImpIDs(request.Imp),
	}

	return []*adapters.RequestData{requestData}, nil
}

func (a *adapter) MakeBids(request *openrtb2.BidRequest, externalRequest *adapters.RequestData, response *adapters.ResponseData) (*adapters.BidderResponse, []error) {
	if adapters.IsResponseStatusCodeNoContent(response) {
		return nil, nil
	}

	if err := adapters.CheckResponseStatusCodeForErrors(response); err != nil {
		return nil, []error{err}
	}

	var bidResp openrtb2.BidResponse

	if err := json.Unmarshal(response.Body, &bidResp); err != nil {
		return nil, []error{err}
	}

	bidResponse := adapters.NewBidderResponse()

	var errs []error
	for _, seatBid := range bidResp.SeatBid {
		for i := range seatBid.Bid {
			bidType, err := getMediaTypeForImp(seatBid.Bid[i].ImpID, request.Imp)
			if err != nil {
				errs = append(errs, err)
				continue
			}

			b := &adapters.TypedBid{
				Bid:     &seatBid.Bid[i],
				BidType: bidType,
			}

			bidResponse.Bids = append(bidResponse.Bids, b)
		}
	}
	return bidResponse, errs
}

func getMediaTypeForImp(impID string, imps []openrtb2.Imp) (openrtb_ext.BidType, error) {
	for _, imp := range imps {
		if imp.ID == impID {
			if imp.Native != nil {
				return openrtb_ext.BidTypeNative, nil
			} else if imp.Video != nil {
				return openrtb_ext.BidTypeVideo, nil
			} else if imp.Banner != nil {
				return openrtb_ext.BidTypeBanner, nil
			}
		}
	}
	return "", fmt.Errorf("Unrecognized impression type in response from nativo: %s", impID)
}