1 /* 2 * Copyright (C) 2017 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.bips.discovery; 18 19 import android.net.Uri; 20 import android.net.wifi.p2p.WifiP2pDevice; 21 import android.util.Log; 22 23 import com.android.bips.BuiltInPrintService; 24 import com.android.bips.P2pPermissionManager; 25 import com.android.bips.p2p.P2pPeerListener; 26 27 /** 28 * Discover previously-added P2P devices, if any. 29 */ 30 public class P2pDiscovery extends SavedDiscovery implements P2pPeerListener { 31 public static final String SCHEME_P2P = "p2p"; 32 private static final String TAG = P2pDiscovery.class.getSimpleName(); 33 private static final boolean DEBUG = false; 34 35 private boolean mDiscoveringPeers = false; 36 private P2pPermissionManager.P2pPermissionRequest mP2pPermissionRequest; 37 P2pDiscovery(BuiltInPrintService printService)38 public P2pDiscovery(BuiltInPrintService printService) { 39 super(printService); 40 } 41 42 /** Convert a peer device to a debug representation */ toPrinter(WifiP2pDevice device)43 public static DiscoveredPrinter toPrinter(WifiP2pDevice device) { 44 Uri path = toPath(device); 45 String deviceName = device.deviceName; 46 if (deviceName.trim().isEmpty()) { 47 deviceName = device.deviceAddress; 48 } 49 return new DiscoveredPrinter(path, deviceName, path, null); 50 } 51 52 /** Convert a peer device address to a Uri-based path */ toPath(WifiP2pDevice device)53 public static Uri toPath(WifiP2pDevice device) { 54 return Uri.parse(SCHEME_P2P + "://" + device.deviceAddress.replace(":", "-")); 55 } 56 57 @Override onStart()58 void onStart() { 59 if (DEBUG) Log.d(TAG, "onStart()"); 60 startPeerDiscovery(); 61 } 62 63 @Override onStop()64 void onStop() { 65 if (DEBUG) Log.d(TAG, "onStop()"); 66 if (mP2pPermissionRequest != null) { 67 mP2pPermissionRequest.close(); 68 mP2pPermissionRequest = null; 69 } 70 if (mDiscoveringPeers) { 71 mDiscoveringPeers = false; 72 getPrintService().getP2pMonitor().stopDiscover(this); 73 allPrintersLost(); 74 } 75 } 76 startPeerDiscovery()77 private void startPeerDiscovery() { 78 // Ignore if already started or no known P2P printers exist 79 if (mDiscoveringPeers || getSavedPrinters().isEmpty()) { 80 return; 81 } 82 83 // Only begin discovery if the user has granted permissions 84 P2pPermissionManager permissionManager = getPrintService().getP2pPermissionManager(); 85 mP2pPermissionRequest = permissionManager.request(true, approved -> { 86 if (approved) { 87 mDiscoveringPeers = true; 88 getPrintService().getP2pMonitor().discover(this); 89 } 90 mP2pPermissionRequest = null; 91 }); 92 } 93 94 @Override onPeerFound(WifiP2pDevice peer)95 public void onPeerFound(WifiP2pDevice peer) { 96 DiscoveredPrinter printer = toPrinter(peer); 97 if (DEBUG) Log.d(TAG, "onPeerFound " + printer); 98 99 // Only find saved printers 100 for (DiscoveredPrinter saved : getSavedPrinters()) { 101 if (saved.path.equals(printer.path)) { 102 printerFound(saved); 103 } 104 } 105 } 106 107 @Override onPeerLost(WifiP2pDevice peer)108 public void onPeerLost(WifiP2pDevice peer) { 109 DiscoveredPrinter printer = toPrinter(peer); 110 if (DEBUG) Log.d(TAG, "onPeerLost " + printer); 111 printerLost(printer.getUri()); 112 } 113 114 /** Adds a known, P2P-discovered, valid printer */ addValidPrinter(DiscoveredPrinter printer)115 public void addValidPrinter(DiscoveredPrinter printer) { 116 if (addSavedPrinter(printer)) { 117 printerFound(printer); 118 if (isStarted()) { 119 startPeerDiscovery(); 120 } 121 } 122 } 123 } 124