From 6eee9e4f11d0dad2c2e965281c63146f7acd0d2f Mon Sep 17 00:00:00 2001
From: Andrew Sapperstein <asapperstein@google.com>
Date: Tue, 24 Jul 2012 12:57:21 -0700
Subject: [PATCH] Filtering attachments by content type.

If the optional contentTypeQueryParameters is
set in the attachments URI, we only include attachments
that start with one of the contentTypes given in the
query parameters.

Change-Id: I97364b405b37174c02ba712009604b4dd122ae73
---
 .../android/email/provider/EmailProvider.java | 30 +++++++++++++++++--
 1 file changed, 28 insertions(+), 2 deletions(-)

diff --git a/src/com/android/email/provider/EmailProvider.java b/src/com/android/email/provider/EmailProvider.java
index e87207f12..77d74a4ed 100644
--- a/src/com/android/email/provider/EmailProvider.java
+++ b/src/com/android/email/provider/EmailProvider.java
@@ -77,6 +77,7 @@ import com.android.emailcommon.service.IEmailServiceCallback;
 import com.android.emailcommon.service.SearchParams;
 import com.android.emailcommon.utility.AttachmentUtilities;
 import com.android.emailcommon.utility.Utility;
+import com.android.ex.photo.provider.PhotoContract;
 import com.android.mail.providers.UIProvider;
 import com.android.mail.providers.UIProvider.AccountCapabilities;
 import com.android.mail.providers.UIProvider.AccountCursorExtraKeys;
@@ -2949,12 +2950,34 @@ outer:
      * Generate the "attachment list" SQLite query, given a projection from UnifiedEmail
      *
      * @param uiProjection as passed from UnifiedEmail
+     * @param contentTypeQueryParameters list of mimeTypes, used as a filter for the attachments
+     * or null if there are no query parameters
      * @return the SQLite query to be executed on the EmailProvider database
      */
-    private String genQueryAttachments(String[] uiProjection) {
+    private String genQueryAttachments(String[] uiProjection,
+            List<String> contentTypeQueryParameters) {
         StringBuilder sb = genSelect(sAttachmentMap, uiProjection);
         sb.append(" FROM " + Attachment.TABLE_NAME + " WHERE " + AttachmentColumns.MESSAGE_KEY +
                 " =? ");
+
+        // Filter for certain content types.
+        // The filter works by adding LIKE operators for each
+        // content type you wish to request. Content types
+        // are filtered by performing a case-insensitive "starts with"
+        // filter. IE, "image/" would return "image/png" as well as "image/jpeg".
+        if (contentTypeQueryParameters != null && !contentTypeQueryParameters.isEmpty()) {
+            final int size = contentTypeQueryParameters.size();
+            sb.append("AND (");
+            for (int i = 0; i < size; i++) {
+                final String contentType = contentTypeQueryParameters.get(i);
+                sb.append(AttachmentColumns.MIME_TYPE + " LIKE '" + contentType + "%'");
+
+                if (i != size - 1) {
+                    sb.append(" OR ");
+                }
+            }
+            sb.append(")");
+        }
         return sb.toString();
     }
 
@@ -3159,7 +3182,10 @@ outer:
                 }
                 break;
             case UI_ATTACHMENTS:
-                c = db.rawQuery(genQueryAttachments(uiProjection), new String[] {id});
+                final List<String> contentTypeQueryParameters =
+                        uri.getQueryParameters(PhotoContract.ContentTypeParameters.CONTENT_TYPE);
+                c = db.rawQuery(genQueryAttachments(uiProjection, contentTypeQueryParameters),
+                        new String[] {id});
                 notifyUri = UIPROVIDER_ATTACHMENTS_NOTIFIER.buildUpon().appendPath(id).build();
                 break;
             case UI_ATTACHMENT: