Add mode: Support for app-provided modes

(This completes the add-mode flow except for the choose-a-name-and-icon step for custom modes).

Bug: 326442408
Flag: android.app.modes_ui
Test: atest com.android.settings.notification.modes
Change-Id: I7aceec01ed54d804bcac53d932277c243c1f81bf

src/com/android/settings/notification/modes/ConfigurationActivityHelper.java

@@ -0,0 +1,143 @@
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.settings.notification.modes;
+
+import static android.app.NotificationManager.EXTRA_AUTOMATIC_RULE_ID;
+
+import android.content.ComponentName;
+import android.content.Intent;
+import android.content.pm.ActivityInfo;
+import android.content.pm.ComponentInfo;
+import android.content.pm.PackageManager;
+import android.content.pm.ResolveInfo;
+import android.service.notification.ConditionProviderService;
+import android.util.Log;
+
+import androidx.annotation.Nullable;
+
+import com.android.settingslib.notification.modes.ZenMode;
+
+import java.util.List;
+import java.util.function.Function;
+
+class ConfigurationActivityHelper {
+
+    private static final String TAG = "ConfigurationActivityHelper";
+
+    private final PackageManager mPm;
+
+    ConfigurationActivityHelper(PackageManager pm) {
+        mPm = pm;
+    }
+
+    @Nullable
+    Intent getConfigurationActivityIntentForMode(ZenMode zenMode,
+            Function<ComponentName, ComponentInfo> approvedServiceFinder) {
+
+        String owner = zenMode.getRule().getPackageName();
+        ComponentName configActivity = null;
+        if (zenMode.getRule().getConfigurationActivity() != null) {
+            // If a configuration activity is present, use that directly in the intent
+            configActivity = zenMode.getRule().getConfigurationActivity();
+        } else {
+            // Otherwise, look for a condition provider service for the rule's package
+            ComponentInfo ci = approvedServiceFinder.apply(zenMode.getRule().getOwner());
+            if (ci != null) {
+                configActivity = extractConfigurationActivityFromComponent(ci);
+            }
+        }
+
+        if (configActivity != null
+                && (owner == null || isSameOwnerPackage(owner, configActivity))
+                && isResolvableActivity(configActivity)) {
+            return new Intent()
+                    .setComponent(configActivity)
+                    .addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP)
+                    .putExtra(ConditionProviderService.EXTRA_RULE_ID, zenMode.getId())
+                    .putExtra(EXTRA_AUTOMATIC_RULE_ID, zenMode.getId());
+        } else {
+            return null;
+        }
+    }
+
+    @Nullable
+    ComponentName getConfigurationActivityFromApprovedComponent(ComponentInfo ci) {
+        ComponentName configActivity = extractConfigurationActivityFromComponent(ci);
+        if (configActivity != null
+                && isSameOwnerPackage(ci.packageName, configActivity)
+                && isResolvableActivity(configActivity)) {
+            return configActivity;
+        } else {
+            return null;
+        }
+    }
+
+    /**
+     * Extract the {@link ComponentName} corresponding to the mode configuration <em>activity</em>
+     * from the component declaring the rule (which may be the Activity itself, or a CPS that points
+     * to the activity in question in its metadata).
+     *
+     * <p>This method doesn't perform any validation, so the activity may or may not exist.
+     */
+    @Nullable
+    private ComponentName extractConfigurationActivityFromComponent(ComponentInfo ci) {
+        if (ci instanceof ActivityInfo) {
+            // New (activity-backed) rule.
+            return new ComponentName(ci.packageName, ci.name);
+        } else if (ci.metaData != null) {
+            // Old (service-backed) rule.
+            final String configurationActivity = ci.metaData.getString(
+                    ConditionProviderService.META_DATA_CONFIGURATION_ACTIVITY);
+            if (configurationActivity != null) {
+                return ComponentName.unflattenFromString(configurationActivity);
+            }
+        }
+        return null;
+    }
+
+    /**
+     * Verifies that the activity is the same package as the rule owner.
+     */
+    private boolean isSameOwnerPackage(String ownerPkg, ComponentName activityName) {
+        try {
+            int ownerUid = mPm.getPackageUid(ownerPkg, 0);
+            int configActivityOwnerUid = mPm.getPackageUid(activityName.getPackageName(), 0);
+            if (ownerUid == configActivityOwnerUid) {
+                return true;
+            } else {
+                Log.w(TAG, String.format("Config activity (%s) not in owner package (%s)",
+                        activityName, ownerPkg));
+                return false;
+            }
+        } catch (PackageManager.NameNotFoundException e) {
+            Log.e(TAG, "Failed to find config activity " + activityName);
+            return false;
+        }
+    }
+
+    /** Verifies that the activity exists and hasn't been disabled. */
+    private boolean isResolvableActivity(ComponentName activityName) {
+        Intent intent = new Intent().setComponent(activityName);
+        List<ResolveInfo> results = mPm.queryIntentActivities(intent, /* flags= */ 0);
+
+        if (intent.resolveActivity(mPm) == null || results.isEmpty()) {
+            Log.w(TAG, "Cannot resolve: " + activityName);
+            return false;
+        }
+        return true;
+    }
+}