Preserve cursor with remote changes in kanban

www/kanban/inner.js

@@ -390,6 +390,75 @@ define([
             $container.addClass('cp-app-readonly');
         });
 
+        var getSelectedElement = function () {
+            var node = document.getSelection().anchorNode;
+            return (node.nodeType === 3 ? node.parentNode : node);
+        };
+        var getCursor = function () {
+            if (!kanban || !kanban.inEditMode) { return; }
+            try {
+                var el = getSelectedElement();
+                var input = $(el).is('input') ? el : $(el).find('input')[0];
+                var $item = $(el).closest('.kanban-item');
+
+                var pos = kanban.findElementPosition($item[0]);
+                var board = $item.closest('.kanban-board').attr('data-id');
+                var val = ($(input).val && $(input).val()) || '';
+                var start = input.selectionStart;
+                var end = input.selectionEnd;
+
+                var boardEl = kanban.options.boards.find(function (b) {
+                    return b.id === board;
+                });
+                var oldVal = boardEl.item[pos] || {};
+
+                return {
+                    board: board,
+                    pos: pos,
+                    value: val,
+                    start: start,
+                    end: end,
+                    oldValue: oldVal.title
+                };
+            } catch (e) {
+                return {};
+            }
+        };
+        var restoreCursor = function (data) {
+            try {
+                var boardEl = kanban.options.boards.find(function (b) {
+                    return b.id === data.board;
+                });
+                if (!boardEl) { return; }
+
+                // An item was added: add a new item
+                if (!data.oldValue) {
+                    var $board = $('.kanban-board[data-id="'+data.board+'"');
+                    $board.find('.kanban-title-button.fa-plus').click();
+                    var $newInput = $board.find('.kanban-item:last-child input');
+                    $newInput.val(data.value);
+                    $newInput[0].selectionStart = data.start;
+                    $newInput[0].selectionEnd = data.end;
+                    return;
+                }
+
+                // An item was edited: click on the correct item
+                var newVal = boardEl.item[data.pos];
+                if (!newVal || newVal.title !== data.oldValue) { return; }
+                var $el = $('.kanban-board[data-id="' + data.board + '"]')
+                            .find('.kanban-item:nth-child('+(data.pos + 1)+')');
+                $el.find('.kanban-item-text').click();
+                var $input = $el.find('input');
+                if ($input.length) {
+                    $input.val(data.value);
+                    $input[0].selectionStart = data.start;
+                    $input[0].selectionEnd = data.end;
+                }
+            } catch (e) {
+                return;
+            }
+        };
+
         framework.onContentUpdate(function (newContent) {
             // Init if needed
             if (!kanban) {
@@ -404,11 +473,12 @@ define([
             var remoteContent = newContent.content;
 
             if (Sortify(currentContent) !== Sortify(remoteContent)) {
-                // reinit kanban (TODO: optimize to diff only)
+                var cursor = getCursor();
                 verbose("Content is different.. Applying content");
                 kanban.setBoards(remoteContent);
                 kanban.inEditMode = false;
                 addRemoveItemButton(framework, kanban);
+                restoreCursor(cursor);
             }
         });