1/*
2 * Copyright (C) 2013 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16package com.android.photos.data;
17
18import android.content.Context;
19import android.database.sqlite.SQLiteDatabase;
20import android.database.sqlite.SQLiteOpenHelper;
21
22import com.android.photos.data.PhotoProvider.Accounts;
23import com.android.photos.data.PhotoProvider.Albums;
24import com.android.photos.data.PhotoProvider.Metadata;
25import com.android.photos.data.PhotoProvider.Photos;
26
27import java.util.ArrayList;
28import java.util.List;
29
30/**
31 * Used in PhotoProvider to create and access the database containing
32 * information about photo and video information stored on the server.
33 */
34public class PhotoDatabase extends SQLiteOpenHelper {
35    @SuppressWarnings("unused")
36    private static final String TAG = PhotoDatabase.class.getSimpleName();
37    static final int DB_VERSION = 3;
38
39    private static final String SQL_CREATE_TABLE = "CREATE TABLE ";
40
41    private static final String[][] CREATE_PHOTO = {
42        { Photos._ID, "INTEGER PRIMARY KEY AUTOINCREMENT" },
43        // Photos.ACCOUNT_ID is a foreign key to Accounts._ID
44        { Photos.ACCOUNT_ID, "INTEGER NOT NULL" },
45        { Photos.WIDTH, "INTEGER NOT NULL" },
46        { Photos.HEIGHT, "INTEGER NOT NULL" },
47        { Photos.DATE_TAKEN, "INTEGER NOT NULL" },
48        // Photos.ALBUM_ID is a foreign key to Albums._ID
49        { Photos.ALBUM_ID, "INTEGER" },
50        { Photos.MIME_TYPE, "TEXT NOT NULL" },
51        { Photos.TITLE, "TEXT" },
52        { Photos.DATE_MODIFIED, "INTEGER" },
53        { Photos.ROTATION, "INTEGER" },
54    };
55
56    private static final String[][] CREATE_ALBUM = {
57        { Albums._ID, "INTEGER PRIMARY KEY AUTOINCREMENT" },
58        // Albums.ACCOUNT_ID is a foreign key to Accounts._ID
59        { Albums.ACCOUNT_ID, "INTEGER NOT NULL" },
60        // Albums.PARENT_ID is a foreign key to Albums._ID
61        { Albums.PARENT_ID, "INTEGER" },
62        { Albums.ALBUM_TYPE, "TEXT" },
63        { Albums.VISIBILITY, "INTEGER NOT NULL" },
64        { Albums.LOCATION_STRING, "TEXT" },
65        { Albums.TITLE, "TEXT NOT NULL" },
66        { Albums.SUMMARY, "TEXT" },
67        { Albums.DATE_PUBLISHED, "INTEGER" },
68        { Albums.DATE_MODIFIED, "INTEGER" },
69        createUniqueConstraint(Albums.PARENT_ID, Albums.TITLE),
70    };
71
72    private static final String[][] CREATE_METADATA = {
73        { Metadata._ID, "INTEGER PRIMARY KEY AUTOINCREMENT" },
74        // Metadata.PHOTO_ID is a foreign key to Photos._ID
75        { Metadata.PHOTO_ID, "INTEGER NOT NULL" },
76        { Metadata.KEY, "TEXT NOT NULL" },
77        { Metadata.VALUE, "TEXT NOT NULL" },
78        createUniqueConstraint(Metadata.PHOTO_ID, Metadata.KEY),
79    };
80
81    private static final String[][] CREATE_ACCOUNT = {
82        { Accounts._ID, "INTEGER PRIMARY KEY AUTOINCREMENT" },
83        { Accounts.ACCOUNT_NAME, "TEXT UNIQUE NOT NULL" },
84    };
85
86    @Override
87    public void onCreate(SQLiteDatabase db) {
88        createTable(db, Accounts.TABLE, getAccountTableDefinition());
89        createTable(db, Albums.TABLE, getAlbumTableDefinition());
90        createTable(db, Photos.TABLE, getPhotoTableDefinition());
91        createTable(db, Metadata.TABLE, getMetadataTableDefinition());
92    }
93
94    public PhotoDatabase(Context context, String dbName, int dbVersion) {
95        super(context, dbName, null, dbVersion);
96    }
97
98    public PhotoDatabase(Context context, String dbName) {
99        super(context, dbName, null, DB_VERSION);
100    }
101
102    @Override
103    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
104        recreate(db);
105    }
106
107    @Override
108    public void onDowngrade(SQLiteDatabase db, int oldVersion, int newVersion) {
109        recreate(db);
110    }
111
112    private void recreate(SQLiteDatabase db) {
113        dropTable(db, Metadata.TABLE);
114        dropTable(db, Photos.TABLE);
115        dropTable(db, Albums.TABLE);
116        dropTable(db, Accounts.TABLE);
117        onCreate(db);
118    }
119
120    protected List<String[]> getAlbumTableDefinition() {
121        return tableCreationStrings(CREATE_ALBUM);
122    }
123
124    protected List<String[]> getPhotoTableDefinition() {
125        return tableCreationStrings(CREATE_PHOTO);
126    }
127
128    protected List<String[]> getMetadataTableDefinition() {
129        return tableCreationStrings(CREATE_METADATA);
130    }
131
132    protected List<String[]> getAccountTableDefinition() {
133        return tableCreationStrings(CREATE_ACCOUNT);
134    }
135
136    protected static void createTable(SQLiteDatabase db, String table, List<String[]> columns) {
137        StringBuilder create = new StringBuilder(SQL_CREATE_TABLE);
138        create.append(table).append('(');
139        boolean first = true;
140        for (String[] column : columns) {
141            if (!first) {
142                create.append(',');
143            }
144            first = false;
145            for (String val: column) {
146                create.append(val).append(' ');
147            }
148        }
149        create.append(')');
150        db.beginTransaction();
151        try {
152            db.execSQL(create.toString());
153            db.setTransactionSuccessful();
154        } finally {
155            db.endTransaction();
156        }
157    }
158
159    protected static String[] createUniqueConstraint(String column1, String column2) {
160        return new String[] {
161                "UNIQUE(", column1, ",", column2, ")"
162        };
163    }
164
165    protected static List<String[]> tableCreationStrings(String[][] createTable) {
166        ArrayList<String[]> create = new ArrayList<String[]>(createTable.length);
167        for (String[] line: createTable) {
168            create.add(line);
169        }
170        return create;
171    }
172
173    protected static void addToTable(List<String[]> createTable, String[][] columns, String[][] constraints) {
174        if (columns != null) {
175            for (String[] column: columns) {
176                createTable.add(0, column);
177            }
178        }
179        if (constraints != null) {
180            for (String[] constraint: constraints) {
181                createTable.add(constraint);
182            }
183        }
184    }
185
186    protected static void dropTable(SQLiteDatabase db, String table) {
187        db.beginTransaction();
188        try {
189            db.execSQL("drop table if exists " + table);
190            db.setTransactionSuccessful();
191        } finally {
192            db.endTransaction();
193        }
194    }
195}
196