Store RTT transcript message received when UI is in background.

If the call disconnects when RTT UI is in background, any messages received from remote should be saved to transcript. RttCallPrensenter might not be available at this point, so the job is done inside DialerCall#onRemovedFromCallList

Bug: 78576798
Test: presubmit
PiperOrigin-RevId: 194821868
Change-Id: I10381b1c292f918763360c7a4bcd0470250f2293

1 files changed, 230 insertions, 0 deletions

diff --git a/java/com/android/incallui/rtt/protocol/RttChatMessage.java b/java/com/android/incallui/rtt/protocol/RttChatMessage.java
new file mode 100644
index 000000000..5680529ee
--- /dev/null
+++ b/java/com/android/incallui/rtt/protocol/RttChatMessage.java
@@ -0,0 +1,230 @@
+/*
+ * Copyright (C) 2018 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.incallui.rtt.protocol;
+
+import android.support.annotation.NonNull;
+import com.android.dialer.common.Assert;
+import com.android.dialer.rtt.RttTranscript;
+import com.android.dialer.rtt.RttTranscriptMessage;
+import com.google.common.base.Splitter;
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+
+/** Message class that holds one RTT chat content. */
+public final class RttChatMessage {
+
+  private static final Splitter SPLITTER = Splitter.on(Constants.BUBBLE_BREAKER);
+
+  public boolean isRemote;
+  private long timstamp;
+  private final StringBuilder content = new StringBuilder();
+  private boolean isFinished;
+
+  public boolean isFinished() {
+    return isFinished;
+  }
+
+  public void finish() {
+    isFinished = true;
+  }
+
+  public void unfinish() {
+    isFinished = false;
+  }
+
+  public void append(String text) {
+    for (int i = 0; i < text.length(); i++) {
+      char c = text.charAt(i);
+      if (c == '\b' && content.length() > 0 && content.charAt(content.length() - 1) != '\b') {
+        content.deleteCharAt(content.length() - 1);
+      } else {
+        content.append(c);
+      }
+    }
+  }
+
+  public String getContent() {
+    return content.toString();
+  }
+
+  /**
+   * Computes delta change of two string.
+   *
+   * <p>e.g. "hello world" -> "hello" : "\b\b\b\b\b\b"
+   *
+   * <p>"hello world" -> "hello mom!" : "\b\b\b\b\bmom!"
+   *
+   * <p>"hello world" -> "hello d" : "\b\b\b\b\bd"
+   *
+   * <p>"hello world" -> "hello new world" : "\b\b\b\b\bnew world"
+   */
+  public static String computeChangedString(String oldMessage, String newMesssage) {
+    StringBuilder modify = new StringBuilder();
+    int indexChangeStart = 0;
+    while (indexChangeStart < oldMessage.length()
+        && indexChangeStart < newMesssage.length()
+        && oldMessage.charAt(indexChangeStart) == newMesssage.charAt(indexChangeStart)) {
+      indexChangeStart++;
+    }
+    for (int i = indexChangeStart; i < oldMessage.length(); i++) {
+      modify.append('\b');
+    }
+    for (int i = indexChangeStart; i < newMesssage.length(); i++) {
+      modify.append(newMesssage.charAt(i));
+    }
+    return modify.toString();
+  }
+
+  public static RttTranscript getRttTranscriptWithNewRemoteMessage(
+      RttTranscript rttTranscript, @NonNull String text) {
+    List<RttChatMessage> messageList = fromTranscript(rttTranscript);
+    updateRemoteRttChatMessage(messageList, text);
+    return RttTranscript.newBuilder()
+        .setId(rttTranscript.getId())
+        .setNumber(rttTranscript.getNumber())
+        .setTimestamp(rttTranscript.getTimestamp())
+        .addAllMessages(toTranscriptMessageList(messageList))
+        .build();
+  }
+
+  /** Update list of {@code RttChatMessage} based on given remote text. */
+  public static void updateRemoteRttChatMessage(
+      List<RttChatMessage> messageList, @NonNull String text) {
+    Assert.isNotNull(messageList);
+    Iterator<String> splitText = SPLITTER.split(text).iterator();
+
+    while (splitText.hasNext()) {
+      String singleMessageContent = splitText.next();
+      RttChatMessage message;
+      int index = getLastIndexUnfinishedRemoteMessage(messageList);
+      if (index < 0) {
+        message = new RttChatMessage();
+        message.append(singleMessageContent);
+        message.isRemote = true;
+        if (splitText.hasNext()) {
+          message.finish();
+        }
+        if (message.content.length() != 0) {
+          messageList.add(message);
+        }
+      } else {
+        message = messageList.get(index);
+        message.append(singleMessageContent);
+        if (splitText.hasNext()) {
+          message.finish();
+        }
+        if (message.content.length() == 0) {
+          messageList.remove(index);
+        }
+      }
+      StringBuilder content = message.content;
+      // Delete previous messages.
+      while (content.length() > 0 && content.charAt(0) == '\b') {
+        messageList.remove(message);
+        content.delete(0, 1);
+        int previous = getLastIndexRemoteMessage(messageList);
+        // There are more backspaces than existing characters.
+        if (previous < 0) {
+          while (content.length() > 0 && content.charAt(0) == '\b') {
+            content.deleteCharAt(0);
+          }
+          // Add message if there are still characters after backspaces.
+          if (content.length() > 0) {
+            message = new RttChatMessage();
+            message.append(content.toString());
+            message.isRemote = true;
+            if (splitText.hasNext()) {
+              message.finish();
+            }
+            messageList.add(message);
+          }
+          break;
+        }
+        message = messageList.get(previous);
+        message.unfinish();
+        message.append(content.toString());
+        content = message.content;
+      }
+    }
+    if (text.endsWith(Constants.BUBBLE_BREAKER)) {
+      int lastIndexRemoteMessage = getLastIndexRemoteMessage(messageList);
+      messageList.get(lastIndexRemoteMessage).finish();
+    }
+  }
+
+  private static int getLastIndexUnfinishedRemoteMessage(List<RttChatMessage> messageList) {
+    int i = messageList.size() - 1;
+    while (i >= 0 && (!messageList.get(i).isRemote || messageList.get(i).isFinished)) {
+      i--;
+    }
+    return i;
+  }
+
+  public static int getLastIndexRemoteMessage(List<RttChatMessage> messageList) {
+    int i = messageList.size() - 1;
+    while (i >= 0 && !messageList.get(i).isRemote) {
+      i--;
+    }
+    return i;
+  }
+
+  public static int getLastIndexLocalMessage(List<RttChatMessage> messageList) {
+    int i = messageList.size() - 1;
+    while (i >= 0 && messageList.get(i).isRemote) {
+      i--;
+    }
+    return i;
+  }
+
+  public static List<RttTranscriptMessage> toTranscriptMessageList(
+      List<RttChatMessage> messageList) {
+    List<RttTranscriptMessage> transcriptMessageList = new ArrayList<>();
+    for (RttChatMessage message : messageList) {
+      transcriptMessageList.add(
+          RttTranscriptMessage.newBuilder()
+              .setContent(message.getContent())
+              .setTimestamp(message.timstamp)
+              .setIsRemote(message.isRemote)
+              .setIsFinished(message.isFinished)
+              .build());
+    }
+    return transcriptMessageList;
+  }
+
+  public static List<RttChatMessage> fromTranscript(RttTranscript rttTranscript) {
+    List<RttChatMessage> messageList = new ArrayList<>();
+    if (rttTranscript == null) {
+      return messageList;
+    }
+    for (RttTranscriptMessage message : rttTranscript.getMessagesList()) {
+      RttChatMessage chatMessage = new RttChatMessage();
+      chatMessage.append(message.getContent());
+      chatMessage.timstamp = message.getTimestamp();
+      chatMessage.isRemote = message.getIsRemote();
+      if (message.getIsFinished()) {
+        chatMessage.finish();
+      }
+      messageList.add(chatMessage);
+    }
+    return messageList;
+  }
+
+  public RttChatMessage() {
+    timstamp = System.currentTimeMillis();
+  }
+}