Started work on fixing issue 42.

Code's not working as desired, yet. Work in progress. :)

lib/ace/edit_session.js

@@ -1,4 +1,5 @@
-/* ***** BEGIN LICENSE BLOCK *****
+/* vim:ts=4:sts=4:sw=4:
+ * ***** BEGIN LICENSE BLOCK *****
  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
  *
  * The contents of this file are subject to the Mozilla Public License Version
@@ -658,6 +659,12 @@ var EditSession = function(text, mode) {
         return addedRows;
     };
 
+    this.moveText = function(range, toPosition) {
+        var removed = this.getTextRange(range);
+        this.doc.remove(range);
+        this.doc.insert(toPosition, removed);
+    };
+
     this.$clipRowToDocument = function(row) {
         return Math.max(0, Math.min(row, this.doc.getLength()-1));
     };

lib/ace/editor.js

@@ -762,6 +762,13 @@ var Editor =function(renderer, session) {
         });
     };
 
+    this.moveText = function(range, toPosition) {
+        if (this.$readOnly)
+            return;
+
+        this.session.moveText(range, toPosition);
+    };
+
     this.copyLinesUp = function() {
         if (this.$readOnly)
             return;

lib/ace/mouse_handler.js

@@ -1,4 +1,5 @@
-/* ***** BEGIN LICENSE BLOCK *****
+/* vim:ts=4:sts=4:sw=4:
+ * ***** BEGIN LICENSE BLOCK *****
  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
  *
  * The contents of this file are subject to the Mozilla Public License Version
@@ -38,6 +39,7 @@
 define(function(require, exports, module) {
 
 var event = require("pilot/event");
+var Range = require("ace/range").Range;
 
 var MouseHandler = function(editor) {
     this.editor = editor;
@@ -75,6 +77,8 @@ var MouseHandler = function(editor) {
         var pos = editor.renderer.screenToTextCoordinates(pageX, pageY);
         pos.row = Math.max(0, Math.min(pos.row, editor.session.getLength()-1));
 
+        var inSelection = false;
+    
         var button = event.getButton(e)
         if (button != 0) {
             var isEmpty = editor.selection.isEmpty()
@@ -86,8 +90,10 @@ var MouseHandler = function(editor) {
                 event.capture(editor.container, function(){}, editor.textInput.onContextMenuClose);
             }
             return;
-        }
+        } else
+            inSelection = editor.getSelectionRange().contains(pos.row, pos.column);
     
+        if (!inSelection) {
             if (e.shiftKey)
                 editor.selection.selectToPosition(pos)
             else {
@@ -95,6 +101,7 @@ var MouseHandler = function(editor) {
                 if (!editor.$clickSelection)
                     editor.selection.clearSelection(pos.row, pos.column);
             }
+        }
 
         editor.renderer.scrollCursorIntoView();
     
@@ -111,6 +118,20 @@ var MouseHandler = function(editor) {
             self.$clickSelection = null;
         };
 
+        var onMouseDragSelectionEnd = function() {
+            clearInterval(timerId);
+
+            var cursor = editor.getCursorPosition();
+            var selection = editor.getSelectionRange();
+            editor.moveText(selection, cursor);
+
+            var rows = selection.end.row - selection.start.row;
+            var columns = selection.end.column - selection.end.column;
+
+            var newSelection = new Range(cursor.row, cursor.column, cursor.row + rows, cursor.column + columns);
+            editor.selection.setSelectionRange(newSelection);
+        };
+    
         var onSelectionInterval = function() {
             if (mousePageX === undefined || mousePageY === undefined)
                 return;
@@ -138,8 +159,24 @@ var MouseHandler = function(editor) {
             editor.renderer.scrollCursorIntoView();
         };
 
+        var onDragSelectionInterval = function() {
+            if (mousePageX === undefined || mousePageY === undefined)
+                return;
+    
+            var cursor = editor.renderer.screenToTextCoordinates(mousePageX, mousePageY);
+            cursor.row = Math.max(0, Math.min(cursor.row, editor.session.getLength()-1));
+    
+            editor.moveCursorToPosition(cursor);
+            editor.renderer.scrollCursorIntoView();
+        };
+
+        if (inSelection) {
+            event.capture(editor.container, onMouseSelection, onMouseDragSelectionEnd);
+            var timerId = setInterval(onDragSelectionInterval, 20);
+        } else {
             event.capture(editor.container, onMouseSelection, onMouseSelectionEnd);
             var timerId = setInterval(onSelectionInterval, 20);
+        }
     
         return event.preventDefault(e);
     };