1 /*
2  * Copyright (C) 2020 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 
17 package com.android.permissioncontroller.permission.ui.model
18 
19 import android.app.Application
20 import android.os.Bundle
21 import androidx.fragment.app.Fragment
22 import androidx.lifecycle.AndroidViewModel
23 import androidx.lifecycle.Transformations
24 import androidx.navigation.fragment.findNavController
25 import com.android.permissioncontroller.R
26 import com.android.permissioncontroller.permission.data.PermGroupsPackagesLiveData
27 import com.android.permissioncontroller.permission.data.PermGroupsPackagesUiInfoLiveData
28 import com.android.permissioncontroller.permission.data.SmartUpdateMediatorLiveData
29 import com.android.permissioncontroller.permission.data.StandardPermGroupNamesLiveData
30 import com.android.permissioncontroller.permission.data.unusedAutoRevokePackagesLiveData
31 import com.android.permissioncontroller.permission.utils.navigateSafe
32 
33 /**
34  * A ViewModel for the ManageStandardPermissionsFragment. Provides a LiveData which watches over all
35  * platform permission groups, and sends async updates when these groups have changes. It also
36  * provides a liveData which watches the custom permission groups of the system, and provides
37  * a list of group names.
38  * @param app The current application of the fragment
39  */
40 class ManageStandardPermissionsViewModel(
41     private val app: Application
42 ) : AndroidViewModel(app) {
43 
44     val uiDataLiveData = PermGroupsPackagesUiInfoLiveData(app,
45         StandardPermGroupNamesLiveData)
46     val numCustomPermGroups = NumCustomPermGroupsWithPackagesLiveData()
47     val numAutoRevoked = Transformations.map(unusedAutoRevokePackagesLiveData) {
48         it?.size ?: 0
49     }
50 
51     /**
52      * Navigate to the Custom Permissions screen
53      *
54      * @param fragment The fragment we are navigating from
55      * @param args The args to pass to the new fragment
56      */
57     fun showCustomPermissions(fragment: Fragment, args: Bundle) {
58         fragment.findNavController().navigateSafe(R.id.standard_to_custom, args)
59     }
60 
61     /**
62      * Navigate to a Permission Apps fragment
63      *
64      * @param fragment The fragment we are navigating from
65      * @param args The args to pass to the new fragment
66      */
67     fun showPermissionApps(fragment: Fragment, args: Bundle) {
68         fragment.findNavController().navigateSafe(R.id.manage_to_perm_apps, args)
69     }
70 
71     fun showAutoRevoke(fragment: Fragment, args: Bundle) {
72         fragment.findNavController().navigateSafe(R.id.manage_to_auto_revoke, args)
73     }
74 }
75 
76 /**
77  * A LiveData which tracks the number of custom permission groups that are used by at least one
78  * package
79  */
80 class NumCustomPermGroupsWithPackagesLiveData() :
81     SmartUpdateMediatorLiveData<Int>() {
82 
83     private val customPermGroupPackages = PermGroupsPackagesLiveData.get(customGroups = true)
84 
85     init {
86         addSource(customPermGroupPackages) {
87             update()
88         }
89     }
90 
91     override fun onUpdate() {
92         value = customPermGroupPackages.value?.size ?: 0
93     }
94 }