2 files changed, 91 insertions, 3 deletions

diff --git a/src/main/java/de/thedevstack/conversationsplus/utils/MessageUtil.java b/src/main/java/de/thedevstack/conversationsplus/utils/MessageUtil.java
index 37e39285..ed144465 100644
--- a/src/main/java/de/thedevstack/conversationsplus/utils/MessageUtil.java
+++ b/src/main/java/de/thedevstack/conversationsplus/utils/MessageUtil.java
@@ -3,6 +3,7 @@ package de.thedevstack.conversationsplus.utils;
 import android.graphics.Bitmap;
 import android.graphics.BitmapFactory;
 
+import java.net.MalformedURLException;
 import java.net.URL;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
@@ -14,18 +15,80 @@ import de.thedevstack.conversationsplus.enums.FileStatus;
 import eu.siacs.conversations.entities.Conversation;
 import eu.siacs.conversations.entities.DownloadableFile;
 import eu.siacs.conversations.entities.Message;
+import eu.siacs.conversations.entities.Transferable;
 import eu.siacs.conversations.persistance.DatabaseBackend;
 import eu.siacs.conversations.persistance.FileBackend;
+import eu.siacs.conversations.utils.FileUtils;
+import eu.siacs.conversations.utils.MimeUtils;
 
 /**
  * Utility class to work with messages.
  */
 public final class MessageUtil {
 
+    public static void extractFileParamsFromBody(Message message) {
+        if (null == message) {
+            return;
+        }
+        String body = message.getBody();
+        /**
+         * there are a few cases where spaces result in an unwanted behavior, e.g.
+         * "http://example.com/image.jpg" text that will not be shown /abc.png"
+         * or more than one image link in one message.
+         */
+        if (null == body || body.isEmpty() || body.contains(" ")) {
+            return;
+        }
+
+        FileParams fileParams = message.getFileParams();
+        if (null == fileParams) {
+            fileParams = new FileParams();
+            message.setFileParams(fileParams);
+        }
+
+        try {
+            URL url = new URL(body);
+            if (!url.getProtocol().equalsIgnoreCase("http") && !url.getProtocol().equalsIgnoreCase("https")) {
+                message.setTreatAsDownloadable(Message.Decision.NEVER);
+                return;
+            }
+            if (message.isHttpUploaded()) {
+                fileParams.setUrl(url.toString());
+                message.setTreatAsDownloadable(Message.Decision.MUST);
+                return;
+            }
+            String extension = FileUtils.getRelevantExtension(url);
+            if (extension == null) {
+                message.setTreatAsDownloadable(Message.Decision.NEVER);
+                return;
+            }
+            byte[] ivAndKey = UrlUtil.getIvAndKeyFromURL(url);
+
+            if (null != ivAndKey) {
+                if (MimeUtils.guessMimeTypeFromExtension(extension) != null) {
+                    message.setTreatAsDownloadable(Message.Decision.MUST);
+                    fileParams.setKeyAndIv(ivAndKey);
+                    fileParams.setUrl(url.toString());
+                } else {
+                    message.setTreatAsDownloadable(Message.Decision.NEVER);
+                }
+            } else if (Transferable.VALID_IMAGE_EXTENSIONS.contains(extension)
+                    || Transferable.WELL_KNOWN_EXTENSIONS.contains(extension)) {
+                message.setTreatAsDownloadable(Message.Decision.SHOULD);
+                fileParams.setUrl(url.toString());
+            } else {
+                message.setTreatAsDownloadable(Message.Decision.NEVER);
+            }
+
+        } catch (MalformedURLException e) {
+            message.setTreatAsDownloadable(Message.Decision.NEVER);
+        }
+    }
+
     public static boolean needsDownload(Message message) {
         FileStatus fileStatus = (null != message.getFileParams()) ? message.getFileParams().getFileStatus() : null;
-        return (null != fileStatus && (fileStatus == FileStatus.NEEDS_DOWNLOAD
-                || fileStatus == FileStatus.UNDEFINED))
+        return (null == fileStatus
+                || (null != fileStatus && (fileStatus == FileStatus.NEEDS_DOWNLOAD || fileStatus == FileStatus.UNDEFINED)))
                 && message.treatAsDownloadable() != Message.Decision.NEVER;
     }
 
@@ -122,6 +185,7 @@ public final class MessageUtil {
         FileParams fileParams = message.getFileParams();
         if (null == fileParams) {
             fileParams = new FileParams();
+            message.setFileParams(fileParams);
         }
         fileParams.setSize(size);
         if (null != url) {
@@ -137,7 +201,6 @@ public final class MessageUtil {
         if (null != relativeFilePathFromMessage && relativeFilePathFromMessage.startsWith("/")) {
             fileParams.setPath(relativeFilePathFromMessage);
         }
-        message.setFileParams(fileParams);
     }
 
     private MessageUtil() {
diff --git a/src/main/java/de/thedevstack/conversationsplus/utils/UrlUtil.java b/src/main/java/de/thedevstack/conversationsplus/utils/UrlUtil.java
new file mode 100644
index 00000000..50c42288
--- /dev/null
+++ b/src/main/java/de/thedevstack/conversationsplus/utils/UrlUtil.java
@@ -0,0 +1,25 @@
+package de.thedevstack.conversationsplus.utils;
+
+import java.net.URL;
+
+import eu.siacs.conversations.utils.CryptoHelper;
+
+/**
+ * This utility class provides helper methods to handle URLs.
+ */
+
+public final class UrlUtil {
+    public static byte[] getIvAndKeyFromURL(URL url) {
+        if (null == url) {
+            return null;
+        }
+        String reference = url.getRef();
+        boolean linkHasIvAndKey = reference != null && reference.matches("([A-Fa-f0-9]{2}){48}");
+
+        return linkHasIvAndKey ? CryptoHelper.hexToBytes(reference) : null;
+    }
+
+    private UrlUtil() {
+        // Helper Class
+    }
+}