1/*
2 * Copyright (C) 2014 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.camera.settings;
18
19import android.content.Context;
20import android.content.SharedPreferences;
21import android.hardware.Camera;
22import android.os.Build;
23import android.preference.PreferenceManager;
24
25import com.android.ex.camera2.portability.Size;
26
27import java.util.List;
28
29/**
30 * Facilitates caching of camera supported picture sizes, which is slow
31 * to query.  Will update cache if Build ID changes.
32 */
33public class CameraPictureSizesCacher {
34    public static final String PICTURE_SIZES_BUILD_KEY = "CachedSupportedPictureSizes_Build_Camera";
35    public static final String PICTURE_SIZES_SIZES_KEY = "CachedSupportedPictureSizes_Sizes_Camera";
36
37    /**
38     * Opportunistically update the picture sizes cache, if needed.
39     *
40     * @param cameraId cameraID we have sizes for.
41     * @param sizes List of valid sizes.
42     */
43    public static void updateSizesForCamera(Context context, int cameraId, List<Size> sizes) {
44        String key_build = PICTURE_SIZES_BUILD_KEY + cameraId;
45        SharedPreferences defaultPrefs = PreferenceManager.getDefaultSharedPreferences(context);
46        String thisCameraCachedBuild = defaultPrefs.getString(key_build, null);
47        // Write to cache.
48        if (thisCameraCachedBuild == null) {
49            String key_sizes = PICTURE_SIZES_SIZES_KEY + cameraId;
50            SharedPreferences.Editor editor = defaultPrefs.edit();
51            editor.putString(key_build, Build.DISPLAY);
52            editor.putString(key_sizes, Size.listToString(sizes));
53            editor.apply();
54        }
55    }
56
57    /**
58     * Return list of Sizes for provided cameraId.  Check first to see if we
59     * have it in the cache for the current android.os.Build.
60     * Note: This method calls Camera.open(), so the camera must be closed
61     * before calling or null will be returned if sizes were not previously
62     * cached.
63     *
64     * @param cameraId cameraID we would like sizes for.
65     * @return List of valid sizes, or null if the Camera can not be opened.
66     */
67    public static List<Size> getSizesForCamera(int cameraId, Context context) {
68        String key_build = PICTURE_SIZES_BUILD_KEY + cameraId;
69        String key_sizes = PICTURE_SIZES_SIZES_KEY + cameraId;
70        SharedPreferences defaultPrefs = PreferenceManager.getDefaultSharedPreferences(context);
71        // Return cached value for cameraId and current build, if available.
72        String thisCameraCachedBuild = defaultPrefs.getString(key_build, null);
73        if (thisCameraCachedBuild != null && thisCameraCachedBuild.equals(Build.DISPLAY)) {
74            String thisCameraCachedSizeList = defaultPrefs.getString(key_sizes, null);
75            if (thisCameraCachedSizeList != null) {
76                return Size.stringToList(thisCameraCachedSizeList);
77            }
78        }
79        // No cached value, so need to query Camera API.
80        Camera thisCamera;
81        try {
82            thisCamera = Camera.open(cameraId);
83        } catch (RuntimeException e) {
84            // Camera open will fail if already open.
85            return null;
86        }
87        if (thisCamera != null) {
88            List<Size> sizes = Size.buildListFromCameraSizes(thisCamera.getParameters()
89                    .getSupportedPictureSizes());
90            thisCamera.release();
91            SharedPreferences.Editor editor = defaultPrefs.edit();
92            editor.putString(key_build, Build.DISPLAY);
93            editor.putString(key_sizes, Size.listToString(sizes));
94            editor.apply();
95            return sizes;
96        }
97        return null;
98    }
99}
100