Use APN defaults when no other APN information is available.

Provides an in-app source for APN info for use in the case that the
device store is unavailable and the user hasn't provided local
connection parameters.

Only covers T-Moble USA, AT&T, and Verizon right now. Only T-Mobile is
tested. Other carriers can be added and tested on an ongoing basis.

src/org/thoughtcrime/securesms/mms/ApnDefaults.java

@@ -0,0 +1,38 @@
+package org.thoughtcrime.securesms.mms;
+
+import android.content.Context;
+import android.telephony.TelephonyManager;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import static org.thoughtcrime.securesms.mms.MmsCommunication.MmsConnectionParameters;
+
+/**
+ * This class provides an in-app source for APN MMSC info for use as a fallback in
+ * the event that the system APN DB is unavailable and the user has not provided
+ * local MMSC configuration details of their own.
+ */
+public class ApnDefaults {
+
+  private static final Map<String, MmsConnectionParameters> paramMap =
+          new HashMap<String, MmsConnectionParameters>(){{
+
+            //T-Mobile USA - Tested: Works
+            put("310260", new MmsConnectionParameters("http://mms.msg.eng.t-mobile.com/mms/wapenc", null, null));
+
+            //AT&T - Untested
+            put("310410", new MmsConnectionParameters("http://mmsc.cingular.com/", "wireless.cingular.com", "80"));
+
+            //Verizon - Untested
+            put("310004", new MmsConnectionParameters("http://mms.vtext.com/servlets/mms", null, null));
+            put("310005", new MmsConnectionParameters("http://mms.vtext.com/servlets/mms", null, null));
+            put("310012", new MmsConnectionParameters("http://mms.vtext.com/servlets/mms", null, null));
+
+          }};
+
+  public static MmsConnectionParameters getMmsConnectionParameters(Context context) {
+    TelephonyManager tm = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE);
+    return paramMap.get(tm.getSimOperator());
+  }
+}

src/org/thoughtcrime/securesms/mms/MmsCommunication.java

@@ -64,6 +64,24 @@ public class MmsCommunication {
     throw new ApnUnavailableException("No locally configured parameters available");
   }
 
+  protected static MmsConnectionParameters getLocalMmsConnectionParameters(Context context)
+      throws ApnUnavailableException
+  {
+    SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(context);
+
+    if (preferences.getBoolean(ApplicationPreferencesActivity.USE_LOCAL_MMS_APNS_PREF, false)) {
+      return getLocallyConfiguredMmsConnectionParameters(context);
+    } else {
+      MmsConnectionParameters params = ApnDefaults.getMmsConnectionParameters(context);
+
+      if (params == null) {
+        throw new ApnUnavailableException("No parameters available from ApnDefaults.");
+      }
+
+      return params;
+    }
+  }
+
   protected static MmsConnectionParameters getMmsConnectionParameters(Context context, String apn,
                                                                       boolean proxyIfPossible)
       throws ApnUnavailableException
@@ -74,7 +92,7 @@ public class MmsCommunication {
       cursor = DatabaseFactory.getMmsDatabase(context).getCarrierMmsInformation(apn);
 
       if (cursor == null || !cursor.moveToFirst())
-        return getLocallyConfiguredMmsConnectionParameters(context);
+        return getLocalMmsConnectionParameters(context);
 
       do {
         String mmsc  = cursor.getString(cursor.getColumnIndexOrThrow("mmsc"));
@@ -91,16 +109,16 @@ public class MmsCommunication {
 
       } while (cursor.moveToNext());
 
-      return getLocallyConfiguredMmsConnectionParameters(context);
+      return getLocalMmsConnectionParameters(context);
     } catch (SQLiteException sqe) {
       Log.w("MmsCommunication", sqe);
-      return getLocallyConfiguredMmsConnectionParameters(context);
+      return getLocalMmsConnectionParameters(context);
     } catch (SecurityException se) {
       Log.w("MmsCommunication", se);
-      return getLocallyConfiguredMmsConnectionParameters(context);
+      return getLocalMmsConnectionParameters(context);
     } catch (IllegalArgumentException iae) {
       Log.w("MmsCommunication", iae);
-      return getLocallyConfiguredMmsConnectionParameters(context);
+      return getLocalMmsConnectionParameters(context);
     } finally {
       if (cursor != null)
         cursor.close();