hugo-medialog/internal/movies/api_trakt.go

package movies

import (
	"context"
	"encoding/json"
	"fmt"
	"hugo-medialog/utils"
	"io/ioutil"
	"log"
	"net/http"
	"net/url"
	"os"
	"strconv"

	"golang.org/x/oauth2"
)

var (
	traktAPIBaseURL   = "https://api.trakt.tv"
	traktClientID     string
	traktClientSecret string
	traktRedirectURI  string
)

var traktOAuthConfig = &oauth2.Config{
	ClientID:     os.Getenv("TRAKT_CLIENT_ID"),
	ClientSecret: os.Getenv("TRAKT_CLIENT_SECRET"),
	Endpoint: oauth2.Endpoint{
		AuthURL:  "https://api.trakt.tv/oauth/authorize",
		TokenURL: "https://api.trakt.tv/oauth/token",
	},
	RedirectURL: os.Getenv("TRAKT_REDIRECT_URI"),
}

func init() {
	// Load runtime variables
	utils.LoadConfig()
	traktClientID = os.Getenv("TRAKT_CLIENT_ID")
	traktClientSecret = os.Getenv("TRAKT_CLIENT_SECRET")
	traktRedirectURI = os.Getenv("TRAKT_REDIRECT_URI")

	if traktClientID == "" || traktClientSecret == "" || traktRedirectURI == "" {
		log.Fatal("Missing Trakt API credentials in environment variables")
	}
}

// Function to fetch a token and save it for reuse
func GetTraktToken() (*oauth2.Token, error) {
	// Check if the token already exists (from a previous session)
	tokenFile := "trakt_token.json"
	if _, err := os.Stat(tokenFile); err == nil {
		// If token file exists, read and return it
		file, err := os.Open(tokenFile)
		if err != nil {
			return nil, err
		}
		defer file.Close()
		token := &oauth2.Token{}
		if err = json.NewDecoder(file).Decode(token); err != nil {
			return nil, err
		}
		return token, nil
	}

	// If no token exists, we need to go through the OAuth flow
	authURL := traktOAuthConfig.AuthCodeURL("state-token", oauth2.AccessTypeOffline)
	fmt.Printf("Visit the URL to authorize: %v\n", authURL)

	// After user authorization, you will receive an authorization code.
	// Once you have the code, get a token by calling the token endpoint.
	var authCode string
	fmt.Print("Enter authorization code: ")
	fmt.Scan(&authCode)

	token, err := traktOAuthConfig.Exchange(context.Background(), authCode)
	if err != nil {
		return nil, err
	}

	// Save the token to file for future use
	file, err := os.Create(tokenFile)
	if err != nil {
		return nil, err
	}
	defer file.Close()

	if err := json.NewEncoder(file).Encode(token); err != nil {
		return nil, err
	}

	return token, nil
}

// Function to get movie details by Trakt ID
func GetMovieByID(traktID int) (*Movie, error) {
	token, err := GetTraktToken()
	if err != nil {
		return nil, err
	}

	client := traktOAuthConfig.Client(context.Background(), token)

	// Call the Trakt API to get movie details by ID
	apiURL := fmt.Sprintf("%s/movies/%s", traktAPIBaseURL, strconv.Itoa(traktID))
	req, _ := http.NewRequest("GET", apiURL, nil)
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("Authorization", "Bearer "+token.AccessToken)
	req.Header.Set("trakt-api-version", "2")
	req.Header.Set("trakt-api-key", traktClientID)

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

	if resp.StatusCode != http.StatusOK {
		return nil, fmt.Errorf("failed to fetch movie: %v", resp.Status)
	}

	body, _ := ioutil.ReadAll(resp.Body)
	var traktMovie Movie
	if err := json.Unmarshal(body, &traktMovie); err != nil {
		return nil, err
	}

	return &traktMovie, nil
}

// Function to search for a movie by title
func SearchMovieByTitle(title string, movie *Movie) error {
	token, err := GetTraktToken()
	if err != nil {
		return err
	}

	client := traktOAuthConfig.Client(context.Background(), token)

	// URL encode the title
	query := url.QueryEscape(title)
	apiURL := fmt.Sprintf("%s/search/movie?query=%s", traktAPIBaseURL, query)
	req, _ := http.NewRequest("GET", apiURL, nil)
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("Authorization", "Bearer "+token.AccessToken)
	req.Header.Set("trakt-api-version", "2")
	req.Header.Set("trakt-api-key", traktClientID)

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

	if resp.StatusCode != http.StatusOK {
		return fmt.Errorf("failed to search movie: %v", resp.Status)
	}

	body, _ := ioutil.ReadAll(resp.Body)

	// utils.DebugBody(body)

	// Parse trakt.tv response to a struct
	var traktResponse []struct {
		Movie struct {
			Title string `json:"title"`
			Year  int    `json:"year"`
			IDs   struct {
				Slug  string `json:"slug"`
				IMDB  string `json:"imdb"`
				TMDB  int    `json:"tmdb"`
				Trakt int    `json:"trakt"`
			} `json:"ids"`
		} `json:"movie"`
	}

	if err := json.Unmarshal(body, &traktResponse); err != nil {
		return err
	}

	if len(traktResponse) == 0 {
		return fmt.Errorf("no movie found with title %s", title)
	}

	// Using 1st result to fill our Movie structure
	foundMovie := traktResponse[0].Movie

	movie.Title = foundMovie.Title
	movie.IDs.Slug = foundMovie.IDs.Slug
	movie.IDs.IMDB = foundMovie.IDs.IMDB
	movie.IDs.TMDB = foundMovie.IDs.TMDB
	movie.IDs.Trakt = foundMovie.IDs.Trakt
	movie.Subtitle = fmt.Sprintf("%d", foundMovie.Year)
	movie.Year = foundMovie.Year
	movie.Link = fmt.Sprintf("https://trakt.tv/movies/%d", foundMovie.IDs.Trakt)

	return nil
}