package streams

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

	"github.com/google/go-querystring/query"
	"go.fifitido.net/twitch/api/types"
)

type GetFollowedStreamsParams struct {
	// The ID of the user whose list of followed streams you want to get. This ID must match the user ID in the access token.
	UserID string `url:"user_id"`

	// The maximum number of items to return per page in the response.
	// The minimum page size is 1 item per page and the maximum is 100 items per page.
	// The default is 100.
	First int `url:"first,omitempty"`

	// The cursor used to get the next page of results.
	// The Pagination object in the response contains the cursor’s value.
	// Read More: https://dev.twitch.tv/docs/api/guide#pagination
	After *types.Cursor `url:"after,omitempty"`
}

type GetFollowedStreamsResponse struct {
	// The list of live streams of broadcasters that the specified user follows.
	// The list is in descending order by the number of viewers watching the stream.
	// Because viewers come and go during a stream, it’s possible to find duplicate or missing streams in the list as you page through the results.
	// The list is empty if none of the followed broadcasters are streaming live.
	Data []Stream `json:"data"`

	// The information used to page through the list of results.
	// The object is empty if there are no more pages left to page through.
	// Read More: https://dev.twitch.tv/docs/api/guide#pagination
	Pagination types.Pagination `json:"pagination"`
}

// Gets the list of broadcasters that the user follows and that are streaming live.
//
// Requires a user access token that includes the user:read:follows scope.
func (s *Streams) GetFollowedStreams(ctx context.Context, params *GetFollowedStreamsParams) (*GetFollowedStreamsResponse, error) {
	v, _ := query.Values(params)
	endpoint := s.baseUrl.ResolveReference(&url.URL{Path: "streams/followed", RawQuery: v.Encode()})

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

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

	statusOK := res.StatusCode >= 200 && res.StatusCode < 300
	if !statusOK {
		return nil, fmt.Errorf("failed to get followed streams (%d)", res.StatusCode)
	}

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

	return &data, nil
}