package predictions

import (
	"context"
	"encoding/json"
	"net/http"
	"net/url"

	"github.com/google/go-querystring/query"
)

type CreatePredictionRequest struct {
	// The ID of the broadcaster that’s running the prediction. This ID must match the user ID in the user access token.
	BroadcasterID string `json:"broadcaster_id"`

	// The question that the broadcaster is asking. For example, Will I finish this entire pizza?
	Title string `json:"title"`

	// The list of possible outcomes that the viewers may choose from. The list must contain a minimum of 2 choices and up to a maximum of 10 choices.
	Outcomes []CreateOutcome `json:"outcomes"`

	// The length of time (in seconds) that the prediction will run for. The minimum is 30 seconds and the maximum is 1800 seconds (30 minutes).
	PredictionWindow int `json:"prediction_window"`
}

type CreateOutcome struct {
	// The text of one of the outcomes that the viewer may select. The title is limited to a maximum of 25 characters.
	Title string `json:"title"`
}

type CreatePredictionResponse struct {
	// A list that contains the single prediction that you created.
	Data []Prediction `json:"data"`
}

// Creates a Channel Points Prediction.
//
// With a Channel Points Prediction, the broadcaster poses a question and viewers try to predict the outcome.
// The prediction runs as soon as it’s created. The broadcaster may run only one prediction at a time.
//
// Requires a user access token that includes the channel:manage:predictions scope.
func (c *Predictions) CreatePrediction(ctx context.Context, params *CreatePredictionRequest) (*CreatePredictionResponse, error) {
	v, _ := query.Values(params)
	endpoint := c.baseUrl.ResolveReference(&url.URL{Path: "predictions", RawQuery: v.Encode()})

	req, err := http.NewRequestWithContext(ctx, http.MethodPost, endpoint.String(), nil)
	if err != nil {
		return nil, err
	}

	res, err := c.client.Do(req)
	if err != nil {
		return nil, err
	}
	defer res.Body.Close()

	var data CreatePredictionResponse
	if err := json.NewDecoder(res.Body).Decode(&data); err != nil {
		return nil, err
	}

	return &data, nil
}