package nobid

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"
)

// NoBidAdapter - NoBid Adapter definition
type NoBidAdapter struct {
	endpoint string
}

// Builder builds a new instance of the NoBid 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 := &NoBidAdapter{
		endpoint: config.Endpoint,
	}
	return bidder, nil
}

// MakeRequests Makes the OpenRTB request payload
func (a *NoBidAdapter) MakeRequests(request *openrtb2.BidRequest, reqInfo *adapters.ExtraRequestInfo) ([]*adapters.RequestData, []error) {

	if len(request.Imp) == 0 {
		return nil, []error{&errortypes.BadInput{
			Message: "No Imps in Bid Request",
		}}
	}

	data, err := json.Marshal(request)
	if err != nil {
		return nil, []error{err}
	}

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

	return []*adapters.RequestData{{
		Method:  "POST",
		Uri:     a.endpoint,
		Body:    data,
		Headers: headers,
		ImpIDs:  openrtb_ext.GetImpIDs(request.Imp),
	}}, []error{}
}

// MakeBids makes the bids
func (a *NoBidAdapter) MakeBids(internalRequest *openrtb2.BidRequest, externalRequest *adapters.RequestData, response *adapters.ResponseData) (*adapters.BidderResponse, []error) {

	if response.StatusCode == http.StatusNoContent {
		return nil, nil
	}

	if response.StatusCode == http.StatusBadRequest {
		return nil, []error{&errortypes.BadInput{
			Message: fmt.Sprintf("Unexpected status code: %d. Run with request.debug = 1 for more info", response.StatusCode),
		}}
	}

	if response.StatusCode != http.StatusOK {
		return nil, []error{&errortypes.BadServerResponse{
			Message: fmt.Sprintf("Unexpected status code: %d. Run with request.debug = 1 for more info", response.StatusCode),
		}}
	}

	var bidResp openrtb2.BidResponse

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

	count := getBidCount(bidResp)
	bidResponse := adapters.NewBidderResponseWithBidsCapacity(count)

	var errs []error

	for _, sb := range bidResp.SeatBid {
		for i := range sb.Bid {
			bidType, err := getMediaTypeForImp(sb.Bid[i].ImpID, internalRequest.Imp)
			if err != nil {
				errs = append(errs, err)
			} else {
				b := &adapters.TypedBid{
					Bid:     &sb.Bid[i],
					BidType: bidType,
				}
				bidResponse.Bids = append(bidResponse.Bids, b)
			}
		}
	}
	return bidResponse, errs
}

func getBidCount(bidResponse openrtb2.BidResponse) int {
	c := 0
	for _, sb := range bidResponse.SeatBid {
		c = c + len(sb.Bid)
	}
	return c
}

func getMediaTypeForImp(impID string, imps []openrtb2.Imp) (openrtb_ext.BidType, error) {
	mediaType := openrtb_ext.BidTypeBanner
	for _, imp := range imps {
		if imp.ID == impID {
			if imp.Banner == nil && imp.Video != nil {
				mediaType = openrtb_ext.BidTypeVideo
			}
			return mediaType, nil
		}
	}

	// This shouldnt happen. Lets handle it just incase by returning an error.
	return "", &errortypes.BadInput{
		Message: fmt.Sprintf("Failed to find impression \"%s\"", impID),
	}
}