HW-03-oop-and-api/src/main/java/movie/apis/MovieService.java

package movie.apis;

import com.google.gson.*;
import com.google.gson.reflect.TypeToken;

import java.io.IOException;
import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.lang.reflect.Type;
import java.util.ArrayList;
import java.util.List;

public class MovieService {

    private final static String GENRES_URL = "https://api.meshcomp.ir/api/v1/genres";
    private final static String MOVIE_BY_ID_URL = "https://api.meshcomp.ir/api/v1/movies/";
    private final static HttpClient client = HttpClient.newHttpClient();

    private String getGenresList() {
        try {
            HttpRequest request = HttpRequest.newBuilder()
                    .uri(URI.create(GENRES_URL))
                    .build();

            HttpResponse<String> response = client.send(request, HttpResponse.BodyHandlers.ofString());

            if (response.statusCode() == 200) {
                System.out.println("Genres List received successfully");
                return response.body();
            } else {
                throw new IOException("HTTP error code: " + response.statusCode());
            }
        } catch (Exception e) {
            System.out.println("!!Exception : " + e.getMessage());
        }
        return null;
    }

    private String getMoviesByGenreList(Long genreId, Long page) {
        try {
            String url = "https://api.meshcomp.ir/api/v1/genres/" + genreId + "/movies?page=" + page;

            HttpRequest request = HttpRequest.newBuilder()
                    .uri(URI.create(url))
                    .build();

            HttpResponse<String> response = client.send(request, HttpResponse.BodyHandlers.ofString());

            if (response.statusCode() == 200) {
                return response.body();
            } else {
                System.out.println("HTTP error code: " + response.statusCode());
                return null;
            }
        } catch (Exception e) {
            System.out.println("!!Exception : " + e.getMessage());
        }
        return null;
    }



    public void displayGenres() {
        String jsonResponse = getGenresList();

        if (jsonResponse == null) {
            System.out.println("Failed to get genres");
            return;
        }

        try {
            JsonObject rootObject = JsonParser.parseString(jsonResponse).getAsJsonObject();
            JsonArray genresArray = rootObject.getAsJsonArray("genres");
            Type genreListType = new TypeToken<ArrayList<Genre>>(){}.getType();
            Gson gson = new Gson();
            List<Genre> genres = gson.fromJson(genresArray, genreListType);

            System.out.println("\nALL GENRES:");
            for (Genre genre : genres) {
                System.out.println(genre.getId() + ". " + genre.getName());
            }
            System.out.println();
        } catch (Exception e) {
            System.err.println("ERROR parsing genres: " + e.getMessage());
        }
    }

    /**
     * TODO 1: Display movies for a specific genre and page
     *
     * Open this link in your browser (and check Pretty-print checkbox) to view json format:
     * https://api.meshcomp.ir/api/v1/genres/1/movies
     *
     * Steps:
     * - Call getMoviesByGenreList(genreId, page) to get JSON
     * - Parse JSON to JsonObject
     * - Get "movies" array (NOT "data")
     * - Loop through array and print: "ID: {id} | {title} ({year})"
     * - Also print total and total_pages
     *
     * PUT ALL PARSING CODE INSIDE try-catch
     */
    public void displayMoviesByGenre(Long genreId, Long page) {
        // TODO: Write your code here
        // All parsing code must be inside try-catch
        try {
            String jsonResponse = getMoviesByGenreList(genreId, page);
            if (jsonResponse == null || jsonResponse.isEmpty()) {
                System.out.println("No response received.");
                return;
            }
            JsonObject rootObject = JsonParser.parseString(jsonResponse).getAsJsonObject();
            JsonArray moviesArray = rootObject.getAsJsonArray("movies");
            int total = rootObject.get("total").getAsInt();
            int totalPages = rootObject.get("total_pages").getAsInt();
            Type movieListType = new TypeToken<ArrayList<Movie>>() {}.getType();
            Gson gson = new Gson();
            List<Movie> movies = gson.fromJson(moviesArray, movieListType);
            System.out.println("Movies:");
            for (Movie movie : movies) {
                System.out.println("ID: " + movie.getId() + " | " + movie.getTitle() + " (" + movie.getYear() + ")");
            }
            System.out.println("Total movies: " + total);
            System.out.println("Total pages: " + totalPages);
        }
        catch (Exception e) {
            System.err.println("ERROR: " + e.getMessage());
        }
    }


    /**
     * BONUS: Fetch movie details from API using movie ID
     * URL format: https://api.meshcomp.ir/api/v1/movies/{movieId}
     */
    private String getMovieById(Long movieId) {
        try {
            // TODO: Complete this method
            // String url = MOVIE_BY_ID_URL + movieId;
            // HttpRequest request = HttpRequest.newBuilder().uri(URI.create(url)).build();
            // HttpResponse<String> response = client.send(request, HttpResponse.BodyHandlers.ofString());
            // if (response.statusCode() == 200) return response.body();

            return null;
        } catch (Exception e) {
            System.out.println("!!Exception : " + e.getMessage());
        }
        return null;
    }

     /*
     BONUS TODO: Display complete movie details for a given movie ID

     Open this link in your browser (and check Pretty-print checkbox) to view json format:
     https://api.meshcomp.ir/api/v1/movies/1

     INSTRUCTIONS:
     1. Call getMovieById(movieId) to get the JSON response string
     2. Check if response is null (if yes, print error and return)
     3. Parse the JSON string to JsonObject (inside try-catch)
     4. Use Gson to extract all fields from the JSON and map them to your Movie class:
        - Add missing JSON fields to your Movie class first (actors, awards, director,
          imdb_id, imdb_votes, metascore, plot, rated, released, runtime, type, writer)
        - Then use Gson to parse your json string
     5. Print all movie details in a readable format

     (PUT ALL PARSING CODE INSIDE THE EXISTING try-catch)
     */

    /* EXAMPLE OUTPUT:

           =======================================================================
                               THE SHAWSHANK REDEMPTION (1994)
           =======================================================================
           Rating: 9.3/10  |  Votes: 1,738,596
           Director: Frank Darabont
           Cast: Tim Robbins, Morgan Freeman, Bob Gunton, William Sadler
           Genre: Crime, Drama
           Runtime: 142 min  |  Rated: R
           Country: USA  |  Released: 14 Oct 1994
           Plot: Two imprisoned men bond over a number of years, finding
           solace and eventual redemption through acts of common decency.
           Awards: Nominated for 7 Oscars. Another 19 wins & 30 nominations.
           =======================================================================

     */

    public void displayMovieDetails(Long movieId) {
        // Step 1: Get JSON response from API
        String jsonResponse = getMovieById(movieId);

        // Step 2: Check if we got valid data
        // Step 3-5: Parse JSON and display details (PUT YOUR CODE INSIDE try-catch)
        if (jsonResponse == null) {
            System.out.println("Failed to get movie details for ID: " + movieId);
            return;
        }
        try {
            // TODO: Parse jsonResponse to JsonObject
            // HINT: Use JsonParser.parseString(jsonResponse).getAsJsonObject()
            // TODO: use Gson to parse the json
            // Your code here:
        } catch (Exception e) {
            System.err.println("ERROR parsing movie details: " + e.getMessage());
        }
    }
}