package net.roarsoftware.lastfm;



import java.util.ArrayList;

import java.util.Collection;

import java.util.Collections;

import java.util.HashMap;

import java.util.List;

import java.util.Map;



import net.roarsoftware.xml.DomElement;



/**

 * Contains bindings for all methods in the "library" namespace.

 *

 * @author Martin Chorley

 * @author Janni Kovacs

 */

public class Library {



	private Library() {

	}



	/**

	 * Retrieves a paginated list of all the artists in a user's library.

	 *

	 * @param user The user whose library you want to fetch.

	 * @param apiKey A Last.fm API key.

	 * @return a {@link PaginatedResult} of the artists

	 */

	public static PaginatedResult<Artist> getArtists(String user, String apiKey) {

		return getArtists(user, 1, 0, apiKey);

	}



	/**

	 * Retrieves a paginated list of all the artists in a user's library.

	 *

	 * @param user The user whose library you want to fetch.

	 * @param page The page number you wish to scan to.

	 * @param apiKey A Last.fm API key.

	 * @return a {@link PaginatedResult} of the artists

	 */

	public static PaginatedResult<Artist> getArtists(String user, int page, String apiKey) {

		return getArtists(user, page, 0, apiKey);

	}



	/**

	 * Retrieves a paginated list of all the artists in a user's library.

	 *

	 * @param user The user whose library you want to fetch.

	 * @param page The page number you wish to scan to.

	 * @param limit Limit the amount of artists returned (maximum/default is 50).

	 * @param apiKey A Last.fm API key.

	 * @return a {@link PaginatedResult} of the artists

	 */

	public static PaginatedResult<Artist> getArtists(String user, int page, int limit, String apiKey) {

		Map<String, String> params = new HashMap<String, String>();

		params.put("user", user);

		params.put("page", String.valueOf(page));

		params.put("limit", String.valueOf(limit));

		Result result = Caller.getInstance().call("library.getArtists", apiKey, params);

		if (!result.isSuccessful())

			return new PaginatedResult<Artist>(0, 0, Collections.<Artist>emptyList());

		DomElement element = result.getContentElement();

		List<Artist> artists = new ArrayList<Artist>();

		for (DomElement domElement : element.getChildren("artist")) {

			artists.add(Artist.artistFromElement(domElement));

		}

		int currentPage = Integer.valueOf(element.getAttribute("page"));

		int totalPages = Integer.valueOf(element.getAttribute("totalPages"));

		return new PaginatedResult<Artist>(currentPage, totalPages, artists);

	}



	/**

	 * Retrieves all artists in a user's library. Pay attention if you use this method as it may produce

	 * a lot of network traffic and therefore may consume a long time.

	 *

	 * @param user The user whose library you want to fetch.

	 * @param apiKey A Last.fm API key.

	 * @return all artists in a user's library

	 */

	public static Collection<Artist> getAllArtists(String user, String apiKey) {

		Collection<Artist> artists = null;

		int page = 1, total;

		do {

			PaginatedResult<Artist> result = getArtists(user, page, apiKey);

			total = result.getTotalPages();

			Collection<Artist> pageResults = result.getPageResults();

			if (artists == null) {

				// artists is initialized here to initialize it with the right size and avoid array copying later on

				artists = new ArrayList<Artist>(total * pageResults.size());

			}

			for (Artist artist : pageResults) {

				artists.add(artist);

			}

			page++;

		} while (page <= total);

		return artists;

	}





	/**

	 * Retrieves a paginated list of all the albums in a user's library.

	 *

	 * @param user The user whose library you want to fetch.

	 * @param apiKey A Last.fm API key.

	 * @return a {@link PaginatedResult} of the albums

	 */

	public static PaginatedResult<Album> getAlbums(String user, String apiKey) {

		return getAlbums(user, 1, 0, apiKey);

	}



	/**

	 * Retrieves a paginated list of all the albums in a user's library.

	 *

	 * @param user The user whose library you want to fetch.

	 * @param page The page number you wish to scan to.

	 * @param apiKey A Last.fm API key.

	 * @return a {@link PaginatedResult} of the albums

	 */

	public static PaginatedResult<Album> getAlbums(String user, int page, String apiKey) {

		return getAlbums(user, page, 0, apiKey);

	}



	/**

	 * Retrieves a paginated list of all the albums in a user's library.

	 *

	 * @param user The user whose library you want to fetch.

	 * @param page The page number you wish to scan to.

	 * @param limit Limit the amount of albumss returned (maximum/default is 50).

	 * @param apiKey A Last.fm API key.

	 * @return a {@link PaginatedResult} of the albums

	 */

	public static PaginatedResult<Album> getAlbums(String user, int page, int limit, String apiKey) {

		Map<String, String> params = new HashMap<String, String>();

		params.put("user", user);

		params.put("page", String.valueOf(page));

		params.put("limit", String.valueOf(limit));

		Result result = Caller.getInstance().call("library.getAlbums", apiKey, params);

		if (!result.isSuccessful())

			return new PaginatedResult<Album>(0, 0, Collections.<Album>emptyList());

		DomElement element = result.getContentElement();

		List<Album> artists = new ArrayList<Album>();

		for (DomElement domElement : element.getChildren("album")) {

			artists.add(Album.albumFromElement(domElement));

		}

		int currentPage = Integer.valueOf(element.getAttribute("page"));

		int totalPages = Integer.valueOf(element.getAttribute("totalPages"));

		return new PaginatedResult<Album>(currentPage, totalPages, artists);

	}



	/**

	 * Retrieves all albums in a user's library. Pay attention if you use this method as it may produce

	 * a lot of network traffic and therefore may consume a long time.

	 *

	 * @param user The user whose library you want to fetch.

	 * @param apiKey A Last.fm API key.

	 * @return all albums in a user's library

	 */

	public static Collection<Album> getAllAlbums(String user, String apiKey) {

		Collection<Album> albums = null;

		int page = 1, total;

		do {

			PaginatedResult<Album> result = getAlbums(user, page, apiKey);

			total = result.getTotalPages();

			Collection<Album> pageResults = result.getPageResults();

			if (albums == null) {

				// albums is initialized here to initialize it with the right size and avoid array copying later on

				albums = new ArrayList<Album>(total * pageResults.size());

			}

			for (Album album : pageResults) {

				albums.add(album);

			}

			page++;

		} while (page <= total);

		return albums;

	}





	/**

	 * Retrieves a paginated list of all the tracks in a user's library.

	 *

	 * @param user The user whose library you want to fetch.

	 * @param apiKey A Last.fm API key.

	 * @return a {@link PaginatedResult} of the tracks

	 */

	public static PaginatedResult<Track> getTracks(String user, String apiKey) {

		return getTracks(user, 1, 0, apiKey);

	}



	/**

	 * Retrieves a paginated list of all the tracks in a user's library.

	 *

	 * @param user The user whose library you want to fetch.

	 * @param page The page number you wish to scan to.

	 * @param apiKey A Last.fm API key.

	 * @return a {@link PaginatedResult} of the tracks

	 */

	public static PaginatedResult<Track> getTracks(String user, int page, String apiKey) {

		return getTracks(user, page, 0, apiKey);

	}



	/**

	 * Retrieves a paginated list of all the tracks in a user's library.

	 *

	 * @param user The user whose library you want to fetch.

	 * @param page The page number you wish to scan to.

	 * @param limit Limit the amount of albumss returned (maximum/default is 50).

	 * @param apiKey A Last.fm API key.

	 * @return a {@link PaginatedResult} of the tracks

	 */

	public static PaginatedResult<Track> getTracks(String user, int page, int limit, String apiKey) {

		Map<String, String> params = new HashMap<String, String>();

		params.put("user", user);

		params.put("page", String.valueOf(page));

		params.put("limit", String.valueOf(limit));

		Result result = Caller.getInstance().call("library.getTracks", apiKey, params);

		if (!result.isSuccessful())

			return new PaginatedResult<Track>(0, 0, Collections.<Track>emptyList());

		DomElement element = result.getContentElement();

		List<Track> tracks = new ArrayList<Track>();

		for (DomElement domElement : element.getChildren("track")) {

			tracks.add(Track.trackFromElement(domElement));

		}

		int currentPage = Integer.valueOf(element.getAttribute("page"));

		int totalPages = Integer.valueOf(element.getAttribute("totalPages"));

		return new PaginatedResult<Track>(currentPage, totalPages, tracks);

	}



	/**

	 * Retrieves all tracks in a user's library. Pay attention if you use this method as it may produce

	 * a lot of network traffic and therefore may consume a long time.

	 *

	 * @param user The user whose library you want to fetch.

	 * @param apiKey A Last.fm API key.

	 * @return all tracks in a user's library

	 */

	public static Collection<Track> getAllTracks(String user, String apiKey) {

		Collection<Track> tracks = null;

		int page = 1, total;

		do {

			PaginatedResult<Track> result = getTracks(user, page, apiKey);

			total = result.getTotalPages();

			Collection<Track> pageResults = result.getPageResults();

			if (tracks == null) {

				// tracks is initialized here to initialize it with the right size and avoid array copying later on

				tracks = new ArrayList<Track>(total * pageResults.size());

			}

			for (Track track : pageResults) {

				tracks.add(track);

			}

			page++;

		} while (page <= total);

		return tracks;

	}





}