package schedule

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

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

type UpdateChannelStreamScheduleSegmentParams struct {
	// The ID of the broadcaster who owns the broadcast segment to update. This ID must match the user ID in the user access token.
	BroadcasterId string `url:"broadcaster_id"`

	// The ID of the broadcast segment to update.
	Id string `url:"id"`
}

type UpdateChannelStreamScheduleSegmentRequest struct {
	// The date and time that the broadcast segment starts. Specify the date and time in RFC3339 format (for example, 2021-07-01T18:00:00Z).
	//
	// NOTE: Only partners and affiliates may update a broadcast’s start time and only for non-recurring segments.
	StartTime *time.Time `json:"start_time"`

	// The length of time, in minutes, that the broadcast is scheduled to run. The duration must be in the range 30 through 1380 (23 hours).
	Duration *int `json:"duration"`

	// The ID of the category that best represents the broadcast’s content.
	// To get the category ID, use the Search Categories endpoint.
	CategoryId *string `json:"category_id"`

	// The broadcast’s title. The title may contain a maximum of 140 characters.
	Title *string `json:"title"`

	// A Boolean value that indicates whether the broadcast is canceled. Set to true to cancel the segment.
	//
	// NOTE: For recurring segments, the API cancels the first segment after the current UTC date and time and not the specified segment
	// (unless the specified segment is the next segment after the current UTC date and time).
	IsCanceled *bool `json:"is_canceled"`

	// The time zone where the broadcast takes place. Specify the time zone using IANA time zone database format (for example, America/New_York).
	Timezone *time.Location `json:"timezone"`
}

type UpdateChannelStreamScheduleSegmentResponse struct {
	// The broadcaster’s streaming schedule.
	Data ChannelStreamSchedule `json:"data"`
}

// Updates a scheduled broadcast segment.
//
// For recurring segments, updating a segment’s title, category, duration, and timezone,
// changes all segments in the recurring schedule, not just the specified segment.
//
// Requires a user access token that includes the channel:manage:schedule scope.
func (s *Schedule) UpdateChannelStreamScheduleSegment(ctx context.Context, params *UpdateChannelStreamScheduleSegmentParams, body *UpdateChannelStreamScheduleSegmentRequest) (*UpdateChannelStreamScheduleSegmentResponse, error) {
	v, _ := query.Values(params)
	endpoint := s.baseUrl.ResolveReference(&url.URL{Path: "schedule/segment", RawQuery: v.Encode()})

	r, w := io.Pipe()

	go func() {
		if err := json.NewEncoder(w).Encode(body); err != nil {
			w.CloseWithError(err)
		} else {
			w.Close()
		}
	}()

	req, err := http.NewRequestWithContext(ctx, http.MethodPatch, endpoint.String(), r)
	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 update channel stream schedule segment (%d)", res.StatusCode)
	}

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

	return &data, nil
}