package main

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

type videoMeta struct {
	Title       string `json:"title"`
	Description string `json:"description"`
}

type ytVideosResponse struct {
	Items []struct {
		Snippet struct {
			Title       string `json:"title"`
			Description string `json:"description"`
		} `json:"snippet"`
	} `json:"items"`
}

type searchResult struct {
	VideoID      string `json:"videoId"`
	Title        string `json:"title"`
	ChannelTitle string `json:"channelTitle"`
	Thumbnail    string `json:"thumbnail"`
}

type ytSearchResponse struct {
	Items []struct {
		ID struct {
			VideoID string `json:"videoId"`
		} `json:"id"`
		Snippet struct {
			Title        string `json:"title"`
			ChannelTitle string `json:"channelTitle"`
			Thumbnails   struct {
				Medium struct {
					URL string `json:"url"`
				} `json:"medium"`
			} `json:"thumbnails"`
		} `json:"snippet"`
	} `json:"items"`
}

func searchVideos(query, apiKey string) ([]searchResult, error) {
	q := url.Values{}
	q.Set("part", "snippet")
	q.Set("type", "video")
	q.Set("maxResults", "12")
	q.Set("q", query)
	q.Set("key", apiKey)

	resp, err := http.Get("https://www.googleapis.com/youtube/v3/search?" + q.Encode())
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		return nil, fmt.Errorf("youtube search status %d", resp.StatusCode)
	}

	var parsed ytSearchResponse
	if err := json.NewDecoder(resp.Body).Decode(&parsed); err != nil {
		return nil, err
	}

	results := make([]searchResult, 0, len(parsed.Items))
	for _, item := range parsed.Items {
		if item.ID.VideoID == "" {
			continue
		}
		results = append(results, searchResult{
			VideoID:      item.ID.VideoID,
			Title:        item.Snippet.Title,
			ChannelTitle: item.Snippet.ChannelTitle,
			Thumbnail:    item.Snippet.Thumbnails.Medium.URL,
		})
	}
	return results, nil
}

func fetchVideoMeta(videoID, apiKey string) (*videoMeta, error) {
	q := url.Values{}
	q.Set("part", "snippet")
	q.Set("id", videoID)
	q.Set("key", apiKey)

	resp, err := http.Get("https://www.googleapis.com/youtube/v3/videos?" + q.Encode())
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		return nil, fmt.Errorf("youtube api status %d", resp.StatusCode)
	}

	var parsed ytVideosResponse
	if err := json.NewDecoder(resp.Body).Decode(&parsed); err != nil {
		return nil, err
	}
	if len(parsed.Items) == 0 {
		return nil, fmt.Errorf("video not found: %s", videoID)
	}

	return &videoMeta{
		Title:       parsed.Items[0].Snippet.Title,
		Description: parsed.Items[0].Snippet.Description,
	}, nil
}