1/*
2 * Copyright (C) 2012 Google Inc.
3 * Licensed to The Android Open Source Project.
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 *      http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17package com.android.mail.bitmap;
18
19import android.content.res.Resources;
20import android.content.res.TypedArray;
21
22import com.android.mail.R;
23
24public interface ColorPicker {
25    /**
26     * Returns the color to use for the given email address.
27     * This method should return the same output for the same input.
28     * @param email The normalized email address.
29     * @return The color value in the format {@code 0xAARRGGBB}.
30     */
31    public int pickColor(final String email);
32
33    /**
34     * A simple implementation of a {@link ColorPicker}.
35     */
36    public class PaletteColorPicker implements ColorPicker {
37        /**
38         * The palette of colors, inflated from {@code R.array.letter_tile_colors}.
39         */
40        private static TypedArray sColors;
41
42        /**
43         * Cached value of {@code sColors.length()}.
44         */
45        private static int sColorCount;
46
47        /**
48         * Default color returned if the one chosen from {@code R.array.letter_tile_colors} is
49         * a {@link android.content.res.ColorStateList}.
50         */
51        private static int sDefaultColor;
52
53        public PaletteColorPicker(Resources res) {
54            if (sColors == null) {
55                sColors = res.obtainTypedArray(R.array.letter_tile_colors);
56                sColorCount = sColors.length();
57                sDefaultColor = res.getColor(R.color.letter_tile_default_color);
58            }
59        }
60
61        @Override
62        public int pickColor(final String email) {
63            final int color = Math.abs(email.hashCode()) % sColorCount;
64            return sColors.getColor(color, sDefaultColor);
65        }
66    }
67}
68