Implement ClickableSpan for user mentions

app/src/main/java/com/zulip/android/ZulipApp.java

@@ -20,6 +20,7 @@
 import com.crashlytics.android.Crashlytics;
 import com.j256.ormlite.dao.Dao;
 import com.j256.ormlite.dao.RuntimeExceptionDao;
+import com.zulip.android.activities.ZulipActivity;
 import com.zulip.android.database.DatabaseHelper;
 import com.zulip.android.models.Message;
 import com.zulip.android.models.Person;
@@ -45,6 +46,15 @@ public class ZulipApp extends Application {
     DatabaseHelper databaseHelper;
     Set<String> mutedTopics;
     private static final String MUTED_TOPIC_KEY = "mutedTopics";
+    private ZulipActivity zulipActivity;
+
+    public ZulipActivity getZulipActivity() {
+        return zulipActivity;
+    }
+
+    public void setZulipActivity(ZulipActivity zulipActivity) {
+        this.zulipActivity = zulipActivity;
+    }
 
     /**
      * Handler to manage batching of unread messages

app/src/main/java/com/zulip/android/activities/ZulipActivity.java

@@ -244,6 +244,7 @@ protected void onCreate(Bundle savedInstanceState) {
         messageEt = (EditText) findViewById(R.id.message_et);
         textView = (TextView) findViewById(R.id.textView);
         sendBtn = (ImageView) findViewById(R.id.send_btn);
+        app.setZulipActivity(this);
         togglePrivateStreamBtn = (ImageView) findViewById(R.id.togglePrivateStream_btn);
         mutedTopics = new ArrayList<>();
         drawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);

app/src/main/java/com/zulip/android/models/Person.java

@@ -126,7 +126,7 @@ public int hashCode() {
                 .toHashCode();
     }
 
-    static Person getByEmail(ZulipApp app, String email) {
+    public static Person getByEmail(ZulipApp app, String email) {
         try {
             Dao<Person, Integer> dao = app.getDatabaseHelper().getDao(
                     Person.class);

app/src/main/java/com/zulip/android/util/CustomHtmlToSpannedConverter.java

@@ -158,6 +158,9 @@ private void handleStartTag(String tag, Attributes attributes) {
             start(mSpannableStringBuilder, new Monospace());
         } else if (tag.equalsIgnoreCase("a")) {
             startA(mSpannableStringBuilder, attributes, mBaseUri);
+        } else if (tag.equalsIgnoreCase("span")
+                && attributes.getValue("class").equals("user-mention")) {
+            startSpan(mSpannableStringBuilder, attributes);
         } else if (tag.equalsIgnoreCase("u")) {
             start(mSpannableStringBuilder, new Underline());
         } else if (tag.equalsIgnoreCase("sup")) {
@@ -255,6 +258,8 @@ private void handleEndTag(String tag) {
                     MONOSPACE));
         } else if (tag.equalsIgnoreCase("a")) {
             endA(mSpannableStringBuilder);
+        } else if (tag.equalsIgnoreCase("span")) {
+            endSpan(mSpannableStringBuilder);
         } else if (tag.equalsIgnoreCase("u")) {
             end(mSpannableStringBuilder, Underline.class, new UnderlineSpan());
         } else if (tag.equalsIgnoreCase("sup")) {
@@ -416,6 +421,26 @@ private static void endFont(SpannableStringBuilder text) {
         }
     }
 
+    private static void startSpan(SpannableStringBuilder text, Attributes attributes) {
+        String email = attributes.getValue("data-user-email");
+        int len = text.length();
+        text.setSpan(new Href(email), len, len, Spannable.SPAN_MARK_MARK);
+    }
+
+    private static void endSpan(SpannableStringBuilder text) {
+        int len = text.length();
+        Object obj = getLast(text, Href.class);
+        int where = text.getSpanStart(obj);
+        text.removeSpan(obj);
+        if (where != len) {
+            Href h = (Href) obj;
+            if (h != null && h.mHref != null) {
+                text.setSpan(new ProfileSpan(h.mHref, userMentionColor), where, len,
+                        Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
+            }
+        }
+    }
+
     private static void startA(SpannableStringBuilder text,
                                Attributes attributes, String baseUri) {
         String href = attributes.getValue("", "href");

app/src/main/java/com/zulip/android/util/ProfileSpan.java

@@ -0,0 +1,48 @@
+package com.zulip.android.util;
+
+import android.content.Context;
+import android.text.TextPaint;
+import android.text.style.ClickableSpan;
+import android.view.View;
+
+import com.zulip.android.ZulipApp;
+import com.zulip.android.filters.NarrowFilterPM;
+import com.zulip.android.models.Person;
+
+import java.sql.SQLException;
+import java.util.ArrayList;
+import java.util.List;
+
+public class ProfileSpan extends ClickableSpan {
+    private String email;
+    private int userMentionColor;
+
+    public ProfileSpan(String email, int color) {
+        this.email = email;
+        userMentionColor = color;
+    }
+
+    @Override
+    public void onClick(View widget) {
+        Context context = widget.getContext().getApplicationContext();
+        List<Person> people = new ArrayList<Person>();
+        if (email.equals("*")) { //This is for "@all"
+            try {
+                people = Person.getAllPeople(ZulipApp.get());
+            } catch (SQLException e) {
+                ZLog.logException(e);
+                return;
+            }
+        } else {
+            for (String email : this.email.split(",")) {
+                people.add(Person.getByEmail(ZulipApp.get(), email));
+            }
+        }
+        (((ZulipApp) context).getZulipActivity()).doNarrow(new NarrowFilterPM(people));
+    }
+
+    @Override
+    public void updateDrawState(TextPaint ds) {
+        ds.setColor(userMentionColor);
+    }
+}