Enable Ctrl+X cut operations, along with some code refactor.

Bug: 27451823
Change-Id: I062dcbd065434c22a3ffeb33d4cac2b4f9da104b
diff --git a/src/com/android/documentsui/DocumentClipper.java b/src/com/android/documentsui/DocumentClipper.java
index 059b5e0..908396c 100644
--- a/src/com/android/documentsui/DocumentClipper.java
+++ b/src/com/android/documentsui/DocumentClipper.java
@@ -23,11 +23,14 @@
 import android.content.Context;
 import android.database.Cursor;
 import android.net.Uri;
+import android.os.PersistableBundle;
 import android.provider.DocumentsContract;
 import android.support.annotation.Nullable;
 import android.util.Log;
 
 import com.android.documentsui.model.DocumentInfo;
+import com.android.documentsui.services.FileOperationService;
+import com.android.documentsui.services.FileOperationService.OpType;
 
 import libcore.io.IoUtils;
 
@@ -42,6 +45,8 @@
 public final class DocumentClipper {
 
     private static final String TAG = "DocumentClipper";
+    private static final String SRC_PARENT_KEY = "srcParent";
+    private static final String OP_TYPE_KEY = "opType";
 
     private Context mContext;
     private ClipboardManager mClipboard;
@@ -73,47 +78,41 @@
     }
 
     /**
-     * Returns a list of Documents as decoded from Clipboard primary clipdata.
-     * This should be run from inside an AsyncTask.
+     * Returns details regarding the documents on the primary clipboard
      */
-    public List<DocumentInfo> getClippedDocuments() {
-        ClipData data = mClipboard.getPrimaryClip();
-        return data == null ? Collections.EMPTY_LIST : getDocumentsFromClipData(data);
+    public ClipDetails getClipDetails() {
+        return getClipDetails(mClipboard.getPrimaryClip());
     }
 
-    /**
-     * Returns a list of Documents as decoded in clipData.
-     * This should be run from inside an AsyncTask.
-     */
-    public List<DocumentInfo> getDocumentsFromClipData(ClipData clipData) {
+    public ClipDetails getClipDetails(@Nullable ClipData clipData) {
+        if (clipData == null) {
+            return null;
+        }
+
+        String srcParent = clipData.getDescription().getExtras().getString(SRC_PARENT_KEY);
+
+        ClipDetails clipDetails = new ClipDetails(
+                clipData.getDescription().getExtras().getInt(OP_TYPE_KEY),
+                getDocumentsFromClipData(clipData),
+                createDocument((srcParent != null) ? Uri.parse(srcParent) : null));
+
+        return clipDetails;
+    }
+
+    private List<DocumentInfo> getDocumentsFromClipData(ClipData clipData) {
         assert(clipData != null);
-        final List<DocumentInfo> srcDocs = new ArrayList<>();
 
         int count = clipData.getItemCount();
         if (count == 0) {
-            return srcDocs;
+            return Collections.EMPTY_LIST;
         }
 
-        ContentResolver resolver = mContext.getContentResolver();
+        final List<DocumentInfo> srcDocs = new ArrayList<>();
+
         for (int i = 0; i < count; ++i) {
             ClipData.Item item = clipData.getItemAt(i);
             Uri itemUri = item.getUri();
-            if (itemUri != null && DocumentsContract.isDocumentUri(mContext, itemUri)) {
-                ContentProviderClient client = null;
-                Cursor cursor = null;
-                try {
-                    client = DocumentsApplication.acquireUnstableProviderOrThrow(
-                            resolver, itemUri.getAuthority());
-                    cursor = client.query(itemUri, null, null, null, null);
-                    cursor.moveToPosition(0);
-                    srcDocs.add(DocumentInfo.fromCursor(cursor, itemUri.getAuthority()));
-                } catch (Exception e) {
-                    Log.e(TAG, e.getMessage());
-                } finally {
-                    IoUtils.closeQuietly(cursor);
-                    ContentProviderClient.releaseQuietly(client);
-                }
-            }
+            srcDocs.add(createDocument(itemUri));
         }
 
         return srcDocs;
@@ -123,26 +122,86 @@
      * Returns ClipData representing the list of docs, or null if docs is empty,
      * or docs cannot be converted.
      */
-    public @Nullable ClipData getClipDataForDocuments(List<DocumentInfo> docs) {
+    public @Nullable ClipData getClipDataForDocuments(List<DocumentInfo> docs, @OpType int opType) {
         final ContentResolver resolver = mContext.getContentResolver();
         ClipData clipData = null;
         for (DocumentInfo doc : docs) {
-            final Uri uri = DocumentsContract.buildDocumentUri(doc.authority, doc.documentId);
+            assert(doc != null);
+            assert(doc.derivedUri != null);
             if (clipData == null) {
                 // TODO: figure out what this string should be.
                 // Currently it is not displayed anywhere in the UI, but this might change.
-                final String label = "";
-                clipData = ClipData.newUri(resolver, label, uri);
+                final String clipLabel = "";
+                clipData = ClipData.newUri(resolver, clipLabel, doc.derivedUri);
+                PersistableBundle bundle = new PersistableBundle();
+                bundle.putInt(OP_TYPE_KEY, opType);
+                clipData.getDescription().setExtras(bundle);
             } else {
                 // TODO: update list of mime types in ClipData.
-                clipData.addItem(new ClipData.Item(uri));
+                clipData.addItem(new ClipData.Item(doc.derivedUri));
             }
         }
         return clipData;
     }
 
-    public void clipDocuments(List<DocumentInfo> docs) {
-        ClipData data = getClipDataForDocuments(docs);
+    /**
+     * Puts {@code ClipData} in a primary clipboard, describing a copy operation
+     */
+    public void clipDocumentsForCopy(List<DocumentInfo> docs) {
+        ClipData data = getClipDataForDocuments(docs, FileOperationService.OPERATION_COPY);
+        assert(data != null);
+
         mClipboard.setPrimaryClip(data);
     }
+
+    /**
+     *  Puts {@Code ClipData} in a primary clipboard, describing a cut operation
+     */
+    public void clipDocumentsForCut(List<DocumentInfo> docs, DocumentInfo srcParent) {
+        assert(docs != null);
+        assert(!docs.isEmpty());
+        assert(srcParent != null);
+        assert(srcParent.derivedUri != null);
+
+        ClipData data = getClipDataForDocuments(docs, FileOperationService.OPERATION_MOVE);
+        assert(data != null);
+
+        PersistableBundle bundle = data.getDescription().getExtras();
+        bundle.putString(SRC_PARENT_KEY, srcParent.derivedUri.toString());
+
+        mClipboard.setPrimaryClip(data);
+    }
+
+    private DocumentInfo createDocument(Uri uri) {
+        DocumentInfo doc = null;
+        if (uri != null && DocumentsContract.isDocumentUri(mContext, uri)) {
+            ContentResolver resolver = mContext.getContentResolver();
+            ContentProviderClient client = null;
+            Cursor cursor = null;
+            try {
+                client = DocumentsApplication.acquireUnstableProviderOrThrow(resolver, uri.getAuthority());
+                cursor = client.query(uri, null, null, null, null);
+                cursor.moveToPosition(0);
+                doc = DocumentInfo.fromCursor(cursor, uri.getAuthority());
+            } catch (Exception e) {
+                Log.e(TAG, e.getMessage());
+            } finally {
+                IoUtils.closeQuietly(cursor);
+                ContentProviderClient.releaseQuietly(client);
+            }
+        }
+        return doc;
+    }
+
+    public static class ClipDetails {
+        public final @OpType int opType;
+        public final List<DocumentInfo> docs;
+        public final @Nullable DocumentInfo parent;
+
+        ClipDetails(@OpType int opType, List<DocumentInfo> docs, @Nullable DocumentInfo parent) {
+            this.opType = opType;
+            this.docs = docs;
+            this.parent = parent;
+        }
+    }
 }