/*

 * Copyright (C) 2010 Google Inc.

 * 

 * Licensed under the Apache License, Version 2.0 (the "License"); you may not

 * use this file except in compliance with the License. You may obtain a copy of

 * the License at

 * 

 * http://www.apache.org/licenses/LICENSE-2.0

 * 

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT

 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the

 * License for the specific language governing permissions and limitations under

 * the License.

 */



package com.marvin.rocklock;



import android.app.Activity;

import android.content.SharedPreferences;

import android.content.SharedPreferences.Editor;

import android.os.Environment;

import android.preference.PreferenceManager;



import java.io.File;

import java.io.FileFilter;



/**

 * SongPicker implementation that uses the directory structure to organize the

 * music instead of using the tags in the music files. For music to be picked

 * up, it has to be put in the /sdcard/RockLock/.music directory.

 * 

 * @author clchen@google.com (Charles L. Chen)

 */

public class DirectoryStructuredSongPicker implements SongPicker {

    private static final String PREF_ARTIST = "DIR_ARTIST";



    private static final String PREF_ALBUM = "DIR_ALBUM";



    private static final String PREF_TRACK = "DIR_TRACK";



    private static final File musicDir = new File(Environment.getExternalStorageDirectory()

            + "/RockLock/.music");



    private class DirectoryFilter implements FileFilter {

        @Override

        public boolean accept(File pathname) {

            if (pathname.isDirectory()) {

                return true;

            }

            return false;

        }

    }



    private class MP3Filter implements FileFilter {

        @Override

        public boolean accept(File pathname) {

            if (pathname.isFile() && pathname.toString().endsWith(".mp3")) {

                return true;

            }

            return false;

        }

    }



    private Editor editor;



    private String currentArtistFullPath;



    private String currentAlbumFullPath;



    private String currentTrackFullPath;



    public DirectoryStructuredSongPicker(Activity parentActivity) {

        SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(parentActivity);

        editor = prefs.edit();

        if (!musicDir.exists()) {

            musicDir.mkdirs();

        }

        if (!restoreFromPrefs(prefs)) {

            currentArtistFullPath = "";

            currentAlbumFullPath = "";

            currentTrackFullPath = "";

            goNextArtist();

        }

    }



    private boolean restoreFromPrefs(SharedPreferences prefs) {

        currentArtistFullPath = prefs.getString(PREF_ARTIST, "");

        currentAlbumFullPath = prefs.getString(PREF_ALBUM, "");

        currentTrackFullPath = prefs.getString(PREF_TRACK, "");

        if (new File(currentArtistFullPath).exists() && new File(currentAlbumFullPath).exists()

                && new File(currentTrackFullPath).exists()) {

            return true;

        }

        return false;

    }



    private String filePathToName(final String filePath) {

        String name = filePath;

        int startIndex = name.lastIndexOf("/") + 1;

        int endIndex = name.lastIndexOf(".");

        if (endIndex > startIndex) {

            return name.substring(startIndex, endIndex);

        } else {

            return name.substring(startIndex);

        }

    }



    public String peekNextArtist() {

        String artist = "";

        File[] artists = musicDir.listFiles(new DirectoryFilter());

        if ((artists == null) || (artists.length == 0)) {

            return "";

        }

        java.util.Arrays.sort(artists);

        if (currentArtistFullPath.length() > 1) {

            boolean moved = false;

            for (int i = 0; i < artists.length - 1; i++) {

                if (currentArtistFullPath.equals(artists[i].getAbsolutePath())) {

                    return filePathToName(artists[i + 1].getAbsolutePath());

                }

            }

        }

        return filePathToName(artists[0].getAbsolutePath());

    }



    public String peekPrevArtist() {

        String artist = "";

        File[] artists = musicDir.listFiles(new DirectoryFilter());

        if ((artists == null) || (artists.length == 0)) {

            return "";

        }

        java.util.Arrays.sort(artists);

        if (currentArtistFullPath.length() > 1) {

            boolean moved = false;

            for (int i = artists.length - 1; i > 0; i--) {

                if (currentArtistFullPath.equals(artists[i].getAbsolutePath())) {

                    return filePathToName(artists[i - 1].getAbsolutePath());

                }

            }

        }

        return filePathToName(artists[artists.length - 1].getAbsolutePath());

    }



    public String goNextArtist() {

        currentArtistFullPath = musicDir + "/" + peekNextArtist();

        currentAlbumFullPath = "";

        goNextAlbum();

        currentTrackFullPath = "";

        goNextTrack();

        return filePathToName(currentArtistFullPath);

    }



    public String goPrevArtist() {

        currentArtistFullPath = musicDir + "/" + peekPrevArtist();

        currentAlbumFullPath = "";

        goNextAlbum();

        currentTrackFullPath = "";

        goNextTrack();

        return filePathToName(currentArtistFullPath);

    }



    public String peekNextAlbum() {

        File artistDir = new File(currentArtistFullPath);

        File[] albums = artistDir.listFiles(new DirectoryFilter());

        if ((albums == null) || (albums.length == 0)) {

            return "";

        }

        java.util.Arrays.sort(albums);

        if (currentAlbumFullPath.length() > 1) {

            boolean moved = false;

            for (int i = 0; i < albums.length - 1; i++) {

                if (currentAlbumFullPath.equals(albums[i].getAbsolutePath())) {

                    return filePathToName(albums[i + 1].getAbsolutePath());

                }

            }

        }

        return filePathToName(albums[0].getAbsolutePath());

    }



    public String goNextAlbum() {

        currentAlbumFullPath = currentArtistFullPath + "/" + peekNextAlbum();

        currentTrackFullPath = "";

        goNextTrack();

        return filePathToName(currentAlbumFullPath);

    }



    public String peekPrevAlbum() {

        File artistDir = new File(currentArtistFullPath);

        File[] albums = artistDir.listFiles(new DirectoryFilter());

        if ((albums == null) || (albums.length == 0)) {

            return "";

        }

        java.util.Arrays.sort(albums);

        if (currentAlbumFullPath.length() > 1) {

            boolean moved = false;

            for (int i = albums.length - 1; i > 0; i--) {

                if (currentAlbumFullPath.equals(albums[i].getAbsolutePath())) {

                    return filePathToName(albums[i - 1].getAbsolutePath());

                }

            }

        }

        return filePathToName(albums[albums.length - 1].getAbsolutePath());

    }



    public String goPrevAlbum() {

        currentAlbumFullPath = currentArtistFullPath + "/" + peekPrevAlbum();

        currentTrackFullPath = "";

        goNextTrack();

        return filePathToName(currentAlbumFullPath);

    }



    public String peekNextTrack() {

        File trackDir = new File(currentAlbumFullPath);

        File[] tracks = trackDir.listFiles(new MP3Filter());

        if ((tracks == null) || (tracks.length == 0)) {

            return "";

        }

        java.util.Arrays.sort(tracks);

        if (currentTrackFullPath.length() > 1) {

            boolean moved = false;

            for (int i = 0; i < tracks.length - 1; i++) {

                if (currentTrackFullPath.equals(tracks[i].getAbsolutePath())) {

                    return filePathToName(tracks[i + 1].getAbsolutePath());

                }

            }

        }

        return filePathToName(tracks[0].getAbsolutePath());

    }



    public String goNextTrack() {

        currentTrackFullPath = currentAlbumFullPath + "/" + peekNextTrack() + ".mp3";

        return filePathToName(currentTrackFullPath);

    }



    public String peekPrevTrack() {

        File trackDir = new File(currentAlbumFullPath);

        File[] tracks = trackDir.listFiles(new MP3Filter());

        if ((tracks == null) || (tracks.length == 0)) {

            return "";

        }

        java.util.Arrays.sort(tracks);

        if (currentTrackFullPath.length() > 1) {

            boolean moved = false;

            for (int i = tracks.length - 1; i > 0; i--) {

                if (currentTrackFullPath.equals(tracks[i].getAbsolutePath())) {

                    return filePathToName(tracks[i - 1].getAbsolutePath());

                }

            }

        }

        return filePathToName(tracks[tracks.length - 1].getAbsolutePath());

    }



    public String goPrevTrack() {

        currentTrackFullPath = currentAlbumFullPath + "/" + peekPrevTrack() + ".mp3";

        return filePathToName(currentTrackFullPath);

    }



    public String getCurrentSongFile() {

        editor.putString(PREF_ARTIST, currentArtistFullPath);

        editor.putString(PREF_ALBUM, currentAlbumFullPath);

        editor.putString(PREF_TRACK, currentTrackFullPath);

        editor.commit();

        return currentTrackFullPath;

    }



    public String getCurrentSongInfo() {

        return filePathToName(currentArtistFullPath) + " - " + filePathToName(currentAlbumFullPath)

                + " - " + filePathToName(currentTrackFullPath);

    }

}