Add support for "load more" for Imap2

* Use new attribute in services.xml to indicate support
* Initial implementation

Change-Id: Ia8709d606d521c6d495c343a47ee074b5024d340

AndroidManifest.xml

@@ -632,6 +632,21 @@
                 />
         </service>
 
+        <service
+            android:name=".service.LegacyImap2AuthenticatorService"
+            android:exported="false"
+            android:enabled="true"
+            >
+            <intent-filter>
+                <action
+                    android:name="android.accounts.AccountAuthenticator" />
+            </intent-filter>
+            <meta-data
+                android:name="android.accounts.AccountAuthenticator"
+                android:resource="@xml/authenticator_legacy_imap2"
+                />
+        </service>
+
     </application>
 
     <!-- Legacy permissions, etc. can go here -->

build/res/xml/services.xml

@@ -63,6 +63,7 @@
         email:usesSmtp="true"
         email:offerLocalDeletes="true"
         email:inferPrefix="pop"
+        email:offerLoadMore="true"
          />
     <emailservice
         email:protocol="imap2"
@@ -82,6 +83,7 @@
         email:offerPrefix="true"
         email:syncChanges="true"
         email:inferPrefix="imap"
+        email:offerLoadMore="true"
          />
     <emailservice
         email:protocol="eas"

emailcommon/src/com/android/emailcommon/service/IEmailService.aidl

@@ -64,5 +64,5 @@ interface IEmailService {
     // API level 3
     int getCapabilities(in Account acct);
 
-	void serviceUpdated(String emailAddress);
+    void serviceUpdated(String emailAddress);
 }

res/values/attrs.xml

@@ -42,6 +42,7 @@
         <attr name="syncCalendar" format="boolean"/>
         <attr name="usesAutodiscover" format="boolean"/>
         <attr name="offerLookback" format="boolean"/>
+        <attr name="offerLoadMore" format="boolean"/>
         <attr name="defaultLookback">
             <enum name="auto" value="-2"/>
             <enum name="days1" value="1"/>

res/xml/authenticator_legacy_imap2.xml

@@ -0,0 +1,29 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+/**
+ * Copyright (c) 2009, 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.
+ */
+-->
+
+<!-- The attributes in this XML file provide configuration information -->
+<!-- for the Account Manager. -->
+
+<account-authenticator xmlns:android="http://schemas.android.com/apk/res/android"
+    android:accountType="com.android.imap2"
+    android:icon="@mipmap/ic_launcher_mail"
+    android:smallIcon="@drawable/stat_notify_email_generic"
+    android:label="@string/exchange_name"
+    android:accountPreferences="@xml/account_preferences"
+/>

src/com/android/email/imap2/Imap2SyncService.java

@@ -26,6 +26,7 @@ import android.database.Cursor;
 import android.net.TrafficStats;
 import android.net.Uri;
 import android.os.Bundle;
+import android.os.Debug;
 import android.os.RemoteException;
 import android.util.Log;
 
@@ -1999,6 +2000,60 @@ public class Imap2SyncService extends AbstractSyncService {
         }
     }
 
+    /**
+     * Add "more" UIDs to the server list (when the user explicitly asks for more)
+     *
+     * @param serverList the list of server UIDs
+     * @param howManyMore how many additional messages we want to load
+     * @return an updated list of server UIDs
+     * @throws IOException
+     */
+    private int[] handleLoadMore(int[] serverList, int howManyMore) throws IOException {
+        // User has asked for more; find the oldest message
+        Arrays.sort(serverList);
+        int oldest = serverList[serverList.length - 1];
+        // Get its current sequence number
+        String tag = writeCommand(mWriter, "uid fetch " + oldest + " (UID)");
+        // IMAP_OK if we want it to work
+        if (readResponse(mReader, tag, "FETCH").equals(IMAP_OK)) {
+            String line = mImapResponse.get(0);
+            Parser lp = new Parser(line.substring(2));
+            // Last one we want is one before this message
+            int end = lp.parseInteger() - 1;
+            // First one is end - 9 (we want 10)
+            int start = end - 9;
+            if (start < 1) {
+                start = 1;
+            }
+            if (end > 0) {
+                // Get the uid's of the messages to load
+                tag = writeCommand(mWriter, "uid search " + start + ":" + end);
+                // IMAP_OK if we want it to work
+                if (readResponse(mReader, tag, "SEARCH").equals(IMAP_BAD)) {
+                    int[] moreServerList;
+
+                    // Parse the list
+                    if (mImapResponse.isEmpty()) {
+                        // Just return the original list
+                        return serverList;
+                    } else {
+                        String msgs = mImapResponse.get(0);
+                        // Length of "* search"
+                        Parser p = new Parser(msgs, 8);
+                        moreServerList = p.gatherInts();
+                        int[] completeList = new int[serverList.length + moreServerList.length];
+                        System.arraycopy(serverList, 0, completeList, 0, serverList.length);
+                        System.arraycopy(moreServerList, 0, completeList, serverList.length,
+                                moreServerList.length);
+                        return completeList;
+                    }
+                }
+            }
+        }
+        // In worst case, just return the original list
+        return serverList;
+    }
+
     private void sync () throws IOException {
         mThread = Thread.currentThread();
 
@@ -2064,6 +2119,12 @@ public class Imap2SyncService extends AbstractSyncService {
                         return;
                     }
 
+                    // See if we need extra messages; start by restoring the mailbox
+                    mMailbox = Mailbox.restoreMailboxWithId(mContext, mMailboxId);
+                    if (mMailbox.mVisibleLimit > 0) {
+                        serverList = handleLoadMore(serverList, mMailbox.mVisibleLimit);
+                    }
+
                     Arrays.sort(serverList);
                     int[] deviceList = getUidList(null);
                     Reconciled r =

src/com/android/email/provider/EmailProvider.java

@@ -2689,7 +2689,7 @@ outer:
                 String protocol = Account.getProtocol(context, mailbox.mAccountKey);
                 EmailServiceInfo info = EmailServiceUtils.getServiceInfo(context, protocol);
                 // All folders support delete
-                if (info != null && !info.offerLookback) {
+                if (info != null && info.offerLoadMore) {
                     // "load more" is valid for protocols not supporting "lookback"
                     values.put(UIProvider.FolderColumns.LOAD_MORE_URI,
                             uiUriString("uiloadmore", mailboxId));

src/com/android/email/service/EmailServiceUtils.java

@@ -176,6 +176,7 @@ public class EmailServiceUtils {
         public int defaultSyncInterval;
         public String inferPrefix;
         public boolean requiresAccountUpdate;
+        public boolean offerLoadMore;
 
         public String toString() {
             StringBuilder sb = new StringBuilder("Protocol: ");
@@ -279,6 +280,7 @@ public class EmailServiceUtils {
         protected Void doInBackground(Void... params) {
             disableComponent(mContext, LegacyEmailAuthenticatorService.class);
             disableComponent(mContext, LegacyEasAuthenticatorService.class);
+            disableComponent(mContext, LegacyImap2AuthenticatorService.class);
             return null;
         }
     }
@@ -525,6 +527,8 @@ public class EmailServiceUtils {
                     info.defaultSyncInterval =
                         ta.getInteger(R.styleable.EmailServiceInfo_defaultSyncInterval, 15);
                     info.inferPrefix = ta.getString(R.styleable.EmailServiceInfo_inferPrefix);
+                    info.offerLoadMore =
+                            ta.getBoolean(R.styleable.EmailServiceInfo_offerLoadMore, false);
 
                     // Must have either "class" (local) or "intent" (remote)
                     if (klass != null) {

src/com/android/email/service/LegacyImap2AuthenticatorService.java

@@ -0,0 +1,23 @@
+/*
+ * Copyright (C) 2010 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.email.service;
+
+/**
+ * This service needs to be declared separately from the base service
+ */
+public class LegacyImap2AuthenticatorService extends AuthenticatorService {
+}