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 */
16
17package com.android.gallery3d.filtershow.data;
18
19import android.content.Context;
20import android.database.sqlite.SQLiteDatabase;
21import android.database.sqlite.SQLiteOpenHelper;
22
23public class FilterStackDBHelper extends SQLiteOpenHelper {
24
25    public static final int DATABASE_VERSION = 1;
26    public static final String DATABASE_NAME = "filterstacks.db";
27    private static final String SQL_CREATE_TABLE = "CREATE TABLE ";
28
29    public static interface FilterStack {
30        /** The row uid */
31        public static final String _ID = "_id";
32        /** The table name */
33        public static final String TABLE = "filterstack";
34        /** The stack name */
35        public static final String STACK_ID = "stack_id";
36        /** A serialized stack of filters. */
37        public static final String FILTER_STACK= "stack";
38    }
39
40    private static final String[][] CREATE_FILTER_STACK = {
41            { FilterStack._ID, "INTEGER PRIMARY KEY AUTOINCREMENT" },
42            { FilterStack.STACK_ID, "TEXT" },
43            { FilterStack.FILTER_STACK, "BLOB" },
44    };
45
46    public FilterStackDBHelper(Context context, String name, int version) {
47        super(context, name, null, version);
48    }
49
50    public FilterStackDBHelper(Context context, String name) {
51        this(context, name, DATABASE_VERSION);
52    }
53
54    public FilterStackDBHelper(Context context) {
55        this(context, DATABASE_NAME);
56    }
57
58    @Override
59    public void onCreate(SQLiteDatabase db) {
60        createTable(db, FilterStack.TABLE, CREATE_FILTER_STACK);
61    }
62
63    @Override
64    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
65        dropTable(db, FilterStack.TABLE);
66        onCreate(db);
67    }
68
69    protected static void createTable(SQLiteDatabase db, String table, String[][] columns) {
70        StringBuilder create = new StringBuilder(SQL_CREATE_TABLE);
71        create.append(table).append('(');
72        boolean first = true;
73        for (String[] column : columns) {
74            if (!first) {
75                create.append(',');
76            }
77            first = false;
78            for (String val : column) {
79                create.append(val).append(' ');
80            }
81        }
82        create.append(')');
83        db.beginTransaction();
84        try {
85            db.execSQL(create.toString());
86            db.setTransactionSuccessful();
87        } finally {
88            db.endTransaction();
89        }
90    }
91
92    protected static void dropTable(SQLiteDatabase db, String table) {
93        db.beginTransaction();
94        try {
95            db.execSQL("drop table if exists " + table);
96            db.setTransactionSuccessful();
97        } finally {
98            db.endTransaction();
99        }
100    }
101}
102