fix handling of sms:, smsto:, mms:, mmsto: URIs

1) add VIEW action and BROWSABLE category to SmsSendtoActivity intent filter
2) created class Rfc5724Uri for processing RFC5724 SMS URIs
3) added a set of tests for new Rfc5724Uri class
4) updated SmsSendtoActivity to use Rfc5742Uri for processing VIEW intents

Fixes #2578
Closes #3030

// FREEBIE

src/org/thoughtcrime/securesms/util/Rfc5724Uri.java

@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2015 Open Whisper Systems
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.thoughtcrime.securesms.util;
+
+import java.net.URISyntaxException;
+import java.net.URLDecoder;
+import java.util.HashMap;
+import java.util.Map;
+
+public class Rfc5724Uri {
+
+  private final String              uri;
+  private final String              schema;
+  private final String              path;
+  private final Map<String, String> queryParams;
+
+  public Rfc5724Uri(String uri) throws URISyntaxException {
+    this.uri         = uri;
+    this.schema      = parseSchema();
+    this.path        = parsePath();
+    this.queryParams = parseQueryParams();
+  }
+
+  private String parseSchema() throws URISyntaxException {
+    String[] parts = uri.split(":");
+
+    if (parts.length < 1 || parts[0].isEmpty()) throw new URISyntaxException(uri, "invalid schema");
+    else                                        return parts[0];
+  }
+
+  private String parsePath() throws URISyntaxException {
+    String[] parts = uri.split("\\?")[0].split(":", 2);
+
+    if (parts.length < 2 || parts[1].isEmpty()) throw new URISyntaxException(uri, "invalid path");
+    else                                        return parts[1];
+  }
+
+  private Map<String, String> parseQueryParams() throws URISyntaxException {
+    Map<String, String> queryParams = new HashMap<>();
+    if (uri.split("\\?").length < 2) {
+      return queryParams;
+    }
+
+    for (String keyValue : uri.split("\\?")[1].split("&")) {
+      String[] parts = keyValue.split("=");
+
+      if (parts.length == 1) queryParams.put(parts[0], "");
+      else                  queryParams.put(parts[0], URLDecoder.decode(parts[1]));
+    }
+
+    return queryParams;
+  }
+
+  public String getSchema() {
+    return schema;
+  }
+
+  public String getPath() {
+    return path;
+  }
+
+  public Map<String, String> getQueryParams() {
+    return queryParams;
+  }
+}