Refactoring of the notebooks cell management.

* Cell insertion code completely rewritten. We now have two methods
  rather than 9: insert_cell_above, insert_cell_below.
* Renaming methods to be more consistent.
* Creating new methods to provide a uniform API.
* Minor bug fixes.

IPython/frontend/html/notebook/static/js/fulleditwidget.js

@@ -1,99 +1,99 b''
 //----------------------------------------------------------------------------
 //  Copyright (C) 2008-2011  The IPython Development Team
 //
 //  Distributed under the terms of the BSD License.  The full license is in
 //  the file COPYING, distributed as part of this software.
 //----------------------------------------------------------------------------
 
 //============================================================================
 // MenuBar
 //============================================================================
 
 var IPython = (function (IPython) {
 
     var FullEditWidget = function (selector) {
         this.selector = selector;
         this.opened = false;
         if (this.selector !== undefined) {
             this.element = $(selector);
             this.style();
             this.bind_events();
         }
     };
 
 
     FullEditWidget.prototype.style = function () {
         var that = this;
         this.element.find('#close_fulledit').button().on('click', function (){
             that.close();
         })
         this.element.find('#fulledit_header').addClass('ui-widget ui-widget-header');
         this.element.find('#fulledit_editor').addClass('ui-widget ui-widget-content');
         this.ace_editor = ace.edit("fulledit_editor");
         this.ace_editor.setTheme("ace/theme/textmate");
         var PythonMode = require("ace/mode/python").Mode;
         this.ace_editor.getSession().setMode(new PythonMode());
         this.ace_editor.getSession().setTabSize(4);
         this.ace_editor.getSession().setUseSoftTabs(true);
         this.ace_editor.setHighlightActiveLine(false);
         // Ace sets its css dynamically, so we need to do this here. These
         // values are chosen to match those of our CodeMirror editors.
         $('.ace_editor').css({fontFamily: 'monospace', fontSize: '110%',
         lineHeight: '1.231'});
     };
 
 
     FullEditWidget.prototype.bind_events = function () {
 
     };
 
 
     FullEditWidget.prototype.open = function () {
-        var cell = IPython.notebook.selected_cell();
+        var cell = IPython.notebook.get_selected_cell();
         if (!this.opened && cell instanceof IPython.CodeCell) {
             $('#fulledit_widget').show();
             $('#main_app').hide();
             $('#menubar').hide();
             $('body').css({overflow : 'auto'});
             var code = cell.get_text();
             this.ace_editor.getSession().setValue(code);
             this.ace_editor.focus();
             // On Safari (and Chrome/FF on Linux) the editor doesn't get
             // focus unless there is a window resize. For now, we trigger it
             // by hand until the bug is fixed upstream.
             window.resizeBy(0,1);
             window.resizeBy(0,-1);
             this.opened = true;
         };
     };
 
 
     FullEditWidget.prototype.close = function () {
         if (this.opened) {
             $('#fulledit_widget').hide();
             $('#main_app').show();
             $('#menubar').show();
             $('body').css({overflow : 'hidden'});
             var code = this.ace_editor.getSession().getValue();
-            var cell = IPython.notebook.selected_cell();
+            var cell = IPython.notebook.get_selected_cell();
             cell.set_text(code);
             cell.select();
             this.opened = false;
         };
     };
 
 
     FullEditWidget.prototype.toggle = function () {
         if (this.opened) {
             this.close();
         } else {
             this.open();
         };
     };
 
 
     IPython.FullEditWidget = FullEditWidget;
 
     return IPython;
 
 }(IPython));

IPython/frontend/html/notebook/static/js/menubar.js

@@ -1,151 +1,151 b''
 //----------------------------------------------------------------------------
 //  Copyright (C) 2008-2011  The IPython Development Team
 //
 //  Distributed under the terms of the BSD License.  The full license is in
 //  the file COPYING, distributed as part of this software.
 //----------------------------------------------------------------------------
 
 //============================================================================
 // MenuBar
 //============================================================================
 
 var IPython = (function (IPython) {
 
     var MenuBar = function (selector) {
         this.selector = selector;
         if (this.selector !== undefined) {
             this.element = $(selector);
             this.style();
             this.bind_events();
         }
     };
 
 
     MenuBar.prototype.style = function () {
         $('ul#menus').menubar({
             select : function (event, ui) {
                 // The selected cell loses focus when the menu is entered, so we
                 // re-select it upon selection.
-                var i = IPython.notebook.selected_index();
+                var i = IPython.notebook.get_selected_index();
                 IPython.notebook.select(i);
             }
         });
     };
 
 
     MenuBar.prototype.bind_events = function () {
         //  File
         this.element.find('#new_notebook').click(function () {
             window.open($('body').data('baseProjectUrl')+'new');
         });
         this.element.find('#open_notebook').click(function () {
             window.open($('body').data('baseProjectUrl'));
         });
         this.element.find('#rename_notebook').click(function () {
             IPython.save_widget.rename_notebook();
         });
         this.element.find('#copy_notebook').click(function () {
             var notebook_id = IPython.save_widget.get_notebook_id();
             var url = $('body').data('baseProjectUrl') + notebook_id + '/copy';
             window.open(url,'_newtab');
         });
         this.element.find('#save_notebook').click(function () {
             IPython.save_widget.save_notebook();
         });
         this.element.find('#download_ipynb').click(function () {
             var notebook_id = IPython.save_widget.get_notebook_id();
             var url = $('body').data('baseProjectUrl') + 'notebooks/' +
                       notebook_id + '?format=json';
             window.open(url,'_newtab');
         });
         this.element.find('#download_py').click(function () {
             var notebook_id = IPython.save_widget.get_notebook_id();
             var url = $('body').data('baseProjectUrl') + 'notebooks/' +
                       notebook_id + '?format=py';
             window.open(url,'_newtab');
         });
         this.element.find('button#print_notebook').click(function () {
             IPython.print_widget.print_notebook();
         });
         // Edit
         this.element.find('#cut_cell').click(function () {
             IPython.notebook.cut_cell();
         });
         this.element.find('#copy_cell').click(function () {
             IPython.notebook.copy_cell();
         });
         this.element.find('#delete_cell').click(function () {
             IPython.notebook.delete_cell();
         });
         this.element.find('#split_cell').click(function () {
             IPython.notebook.split_cell();
         });
         this.element.find('#merge_cell_above').click(function () {
             IPython.notebook.merge_cell_above();
         });
         this.element.find('#merge_cell_below').click(function () {
             IPython.notebook.merge_cell_below();
         });
         this.element.find('#move_cell_up').click(function () {
             IPython.notebook.move_cell_up();
         });
         this.element.find('#move_cell_down').click(function () {
             IPython.notebook.move_cell_down();
         });
         this.element.find('#select_previous').click(function () {
             IPython.notebook.select_prev();
         });
         this.element.find('#select_next').click(function () {
             IPython.notebook.select_next();
         });
         // Insert
         this.element.find('#insert_cell_above').click(function () {
-            IPython.notebook.insert_code_cell_above();
+            IPython.notebook.insert_cell_above('code');
         });
         this.element.find('#insert_cell_below').click(function () {
-            IPython.notebook.insert_code_cell_below();
+            IPython.notebook.insert_cell_below('code');
         });
         // Cell
         this.element.find('#full_edit_cell').click(function () {
             IPython.fulledit_widget.open();
         });
         this.element.find('#run_cell').click(function () {
             IPython.notebook.execute_selected_cell();
         });
         this.element.find('#run_cell_in_place').click(function () {
             IPython.notebook.execute_selected_cell({terminal:true});
         });
         this.element.find('#run_all_cells').click(function () {
             IPython.notebook.execute_all_cells();
         });
         this.element.find('#to_code').click(function () {
             IPython.notebook.to_code();
         });
         this.element.find('#to_markdown').click(function () {
             IPython.notebook.to_markdown();
         });
         this.element.find('#toggle_output').click(function () {
             IPython.notebook.toggle_output();
         });
         this.element.find('#clear_all_output').click(function () {
             IPython.notebook.clear_all_output();
         });
         // Kernel
         this.element.find('#int_kernel').click(function () {
             IPython.notebook.kernel.interrupt();
         });
         this.element.find('#restart_kernel').click(function () {
             IPython.notebook.restart_kernel();
         });
         // Help
         this.element.find('#keyboard_shortcuts').click(function () {
             IPython.quick_help.show_keyboard_shortcuts();
         });
     };
 
 
     IPython.MenuBar = MenuBar;
 
     return IPython;
 
 }(IPython));

IPython/frontend/html/notebook/static/js/notebook.js

@@ -1,1186 +1,1180 b''
 //----------------------------------------------------------------------------
 //  Copyright (C) 2008-2011  The IPython Development Team
 //
 //  Distributed under the terms of the BSD License.  The full license is in
 //  the file COPYING, distributed as part of this software.
 //----------------------------------------------------------------------------
 
 //============================================================================
 // Notebook
 //============================================================================
 
 var IPython = (function (IPython) {
 
     var utils = IPython.utils;
 
     var Notebook = function (selector) {
         this.read_only = IPython.read_only;
         this.element = $(selector);
         this.element.scroll();
         this.element.data("notebook", this);
         this.next_prompt_number = 1;
         this.kernel = null;
         this.clipboard = null;
         this.paste_enabled = false;
         this.dirty = false;
         this.msg_cell_map = {};
         this.metadata = {};
         this.control_key_active = false;
         this.style();
         this.create_elements();
         this.bind_events();
         this.set_tooltipontab(true);
         this.set_smartcompleter(true);
         this.set_timebeforetooltip(1200);
         this.set_autoindent(true);
     };
 
 
     Notebook.prototype.style = function () {
         $('div#notebook').addClass('border-box-sizing');
     };
 
 
     Notebook.prototype.create_elements = function () {
         // We add this end_space div to the end of the notebook div to:
         // i) provide a margin between the last cell and the end of the notebook
         // ii) to prevent the div from scrolling up when the last cell is being
         // edited, but is too low on the page, which browsers will do automatically.
         var that = this;
-        var end_space = $('<div class="end_space"></div>').height("30%");
+        var end_space = $('<div/>').addClass('end_space').height("30%");
         end_space.dblclick(function (e) {
             if (that.read_only) return;
             var ncells = that.ncells();
-            that.insert_code_cell_below(ncells-1);
+            that.insert_cell_below('code',ncells-1);
         });
         this.element.append(end_space);
         $('div#notebook').addClass('border-box-sizing');
     };
 
 
     Notebook.prototype.bind_events = function () {
         var that = this;
         $(document).keydown(function (event) {
             // console.log(event);
             if (that.read_only) return true;
             if (event.which === 27) {
                 // Intercept escape at highest level to avoid closing 
                 // websocket connection with firefox
                 event.preventDefault();
             }
             if (event.which === 38 && !event.shiftKey) {
-                var cell = that.selected_cell();
+                var cell = that.get_selected_cell();
                 if (cell.at_top()) {
                     event.preventDefault();
                     that.select_prev();
                 };
             } else if (event.which === 40 && !event.shiftKey) {
-                var cell = that.selected_cell();
+                var cell = that.get_selected_cell();
                 if (cell.at_bottom()) {
                     event.preventDefault();
                     that.select_next();
                 };
             } else if (event.which === 13 && event.shiftKey) {
                 that.execute_selected_cell();
                 return false;
             } else if (event.which === 13 && event.ctrlKey) {
                 that.execute_selected_cell({terminal:true});
                 return false;
             } else if (event.which === 77 && event.ctrlKey) {
                 that.control_key_active = true;
                 return false;
             } else if (event.which === 88 && that.control_key_active) {
                 // Cut selected cell = x
                 that.cut_cell();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 67 && that.control_key_active) {
                 // Copy selected cell = c
                 that.copy_cell();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 86 && that.control_key_active) {
                 // Paste selected cell = v
                 that.paste_cell();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 68 && that.control_key_active) {
                 // Delete selected cell = d
                 that.delete_cell();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 65 && that.control_key_active) {
                 // Insert code cell above selected = a
-                that.insert_code_cell_above();
+                that.insert_cell_above('code');
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 66 && that.control_key_active) {
                 // Insert code cell below selected = b
-                that.insert_code_cell_below();
+                that.insert_cell_below('code');
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 89 && that.control_key_active) {
                 // To code = y
                 that.to_code();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 77 && that.control_key_active) {
                 // To markdown = m
                 that.to_markdown();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 84 && that.control_key_active) {
                 // Toggle output = t
                 that.toggle_output();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 83 && that.control_key_active) {
                 // Save notebook = s
                 IPython.save_widget.save_notebook();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 74 && that.control_key_active) {
                 // Move cell down = j
                 that.move_cell_down();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 75 && that.control_key_active) {
                 // Move cell up = k
                 that.move_cell_up();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 80 && that.control_key_active) {
                 // Select previous = p
                 that.select_prev();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 78 && that.control_key_active) {
                 // Select next = n
                 that.select_next();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 76 && that.control_key_active) {
                 // Toggle line numbers = l
                 that.cell_toggle_line_numbers();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 73 && that.control_key_active) {
                 // Interrupt kernel = i
                 IPython.notebook.kernel.interrupt();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 190 && that.control_key_active) {
                 // Restart kernel = .  # matches qt console
                 IPython.notebook.restart_kernel();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 72 && that.control_key_active) {
                 // Show keyboard shortcuts = h
                 IPython.quick_help.show_keyboard_shortcuts();
                 that.control_key_active = false;
                 return false;
             } else if (event.which === 69 && that.control_key_active) {
                 // Edit in Ace = e
                 IPython.fulledit_widget.toggle();
                 that.control_key_active = false;
                 return false;
             } else if (that.control_key_active) {
                 that.control_key_active = false;
                 return true;
             };
             return true;
         });
 
         this.element.bind('collapse_pager', function () {
             var app_height = $('div#main_app').height(); // content height
             var splitter_height = $('div#pager_splitter').outerHeight(true);
             var new_height = app_height - splitter_height;
             that.element.animate({height : new_height + 'px'}, 'fast');
         });
 
         this.element.bind('expand_pager', function () {
             var app_height = $('div#main_app').height(); // content height
             var splitter_height = $('div#pager_splitter').outerHeight(true);
             var pager_height = $('div#pager').outerHeight(true);
             var new_height = app_height - pager_height - splitter_height; 
             that.element.animate({height : new_height + 'px'}, 'fast');
         });
 
         $(window).bind('beforeunload', function () {
             // TODO: Make killing the kernel configurable.
             var kill_kernel = false;
             if (kill_kernel) {
                 that.kernel.kill();
             }
             if (that.dirty && ! that.read_only) {
                 return "You have unsaved changes that will be lost if you leave this page.";
             };
             // Null is the *only* return value that will make the browser not
             // pop up the "don't leave" dialog.
             return null;
         });
     };
 
 
     Notebook.prototype.scroll_to_bottom = function () {
         this.element.animate({scrollTop:this.element.get(0).scrollHeight}, 0);
     };
 
 
     Notebook.prototype.scroll_to_top = function () {
         this.element.animate({scrollTop:0}, 0);
     };
 
 
     // Cell indexing, retrieval, etc.
 
-
-    Notebook.prototype.cell_elements = function () {
+    Notebook.prototype.get_cell_elements = function () {
         return this.element.children("div.cell");
     };
 
 
+    Notebook.prototype.get_cell_element = function (index) {
+        var result = null;
+        var e = this.get_cell_elements().eq(index);
+        if (e.length !== 0) {
+            result = e;
+        }
+        return result;
+    };
+
+
     Notebook.prototype.ncells = function (cell) {
-        return this.cell_elements().length;
+        return this.get_cell_elements().length;
     };
 
 
     // TODO: we are often calling cells as cells()[i], which we should optimize
     // to cells(i) or a new method.
-    Notebook.prototype.cells = function () {
-        return this.cell_elements().toArray().map(function (e) {
+    Notebook.prototype.get_cells = function () {
+        return this.get_cell_elements().toArray().map(function (e) {
             return $(e).data("cell");
         });
     };
 
 
+    Notebook.prototype.get_cell = function (index) {
+        var result = null;
+        var ce = this.get_cell_element(index);
+        if (ce !== null) {
+            result = ce.data('cell');
+        }
+        return result;
+    }
+
+
+    Notebook.prototype.get_next_cell = function (cell) {
+        var result = null;
+        var index = this.find_cell_index(cell);
+        if (index !== null && index < this.ncells()) {
+            result = this.get_cell(index+1);
+        }
+        return result;
+    }
+
+
+    Notebook.prototype.get_prev_cell = function (cell) {
+        var result = null;
+        var index = this.find_cell_index(cell);
+        if (index !== null && index > 1) {
+            result = this.get_cell(index-1);
+        }
+        return result;
+    }
+
     Notebook.prototype.find_cell_index = function (cell) {
         var result = null;
-        this.cell_elements().filter(function (index) {
+        this.get_cell_elements().filter(function (index) {
             if ($(this).data("cell") === cell) {
                 result = index;
             };
         });
         return result;
     };
 
 
     Notebook.prototype.index_or_selected = function (index) {
         var i;
-        if (index === undefined) {
-            i = this.selected_index();
+        if (index === undefined || index === null) {
+            i = this.get_selected_index();
             if (i === null) {
                 i = 0;
             }
         } else {
             i = index;
         }
         return i;
     };
 
 
-    Notebook.prototype.select = function (index) {
-        if (index !== undefined && index >= 0 && index < this.ncells()) {
-            if (this.selected_index() !== null) {
-                this.selected_cell().unselect();
-            };
-            this.cells()[index].select();
+    Notebook.prototype.get_selected_cell = function () {
+        var index = this.get_selected_index();
+        return this.get_cell(index);
         };
-        return this;
-    };
-
 
-    Notebook.prototype.select_next = function () {
-        var index = this.selected_index();
-        if (index !== null && index >= 0 && (index+1) < this.ncells()) {
-            this.select(index+1);
-        };
-        return this;
-    };
 
-
-    Notebook.prototype.select_prev = function () {
-        var index = this.selected_index();
-        if (index !== null && index >= 0 && (index-1) < this.ncells()) {
-            this.select(index-1);
-        };
-        return this;
+    Notebook.prototype.is_valid_cell_index = function (index) {
+        if (index !== null && index >= 0 && index < this.ncells()) {
+            return true;
+        } else {
+            return false;
     };
+    }
 
-
-    Notebook.prototype.selected_index = function () {
+    Notebook.prototype.get_selected_index = function () {
         var result = null;
-        this.cell_elements().filter(function (index) {
+        this.get_cell_elements().filter(function (index) {
             if ($(this).data("cell").selected === true) {
                 result = index;
             };
         });
         return result;
     };
 
 
     Notebook.prototype.cell_for_msg = function (msg_id) {
         var cell_id = this.msg_cell_map[msg_id];
         var result = null;
-        this.cell_elements().filter(function (index) {
+        this.get_cell_elements().filter(function (index) {
             cell = $(this).data("cell");
             if (cell.cell_id === cell_id) {
                 result = cell;
             };
         });
         return result;
     };
 
 
-    Notebook.prototype.selected_cell = function () {
-        return this.cell_elements().eq(this.selected_index()).data("cell");
-    };
-
+    // Cell selection.
 
-    // Cell insertion, deletion and moving.
-
-    Notebook.prototype.delete_cell = function (index) {
-        var i = this.index_or_selected(index);
-        if (i !== null && i >= 0 && i < this.ncells()) {
-            this.cell_elements().eq(i).remove();
-            if (i === (this.ncells())) {
-                this.select(i-1);
-            } else {
-                this.select(i);
+    Notebook.prototype.select = function (index) {
+        if (index !== undefined && index >= 0 && index < this.ncells()) {
+            sindex = this.get_selected_index()
+            if (sindex !== null) {
+                this.get_cell(sindex).unselect();
             };
+            this.get_cell(index).select();
         };
-        this.dirty = true;
-        return this;
-    };
-
-
-    Notebook.prototype.append_cell = function (cell) {
-        this.element.find('div.end_space').before(cell.element);
-        this.dirty = true;
         return this;
     };
 
 
-    Notebook.prototype.insert_cell_below = function (cell, index) {
-        var ncells = this.ncells();
-        if (ncells === 0) {
-            this.append_cell(cell);
-            return this;
-        };
-        if (index >= 0 && index < ncells) {
-            this.cell_elements().eq(index).after(cell.element);
+    Notebook.prototype.select_next = function () {
+        var index = this.get_selected_index();
+        if (index !== null && index >= 0 && (index+1) < this.ncells()) {
+            this.select(index+1);
         };
-        this.dirty = true;
         return this;
     };
 
 
-    Notebook.prototype.insert_cell_above = function (cell, index) {
-        var ncells = this.ncells();
-        if (ncells === 0) {
-            this.append_cell(cell);
-            return this;
-        };
-        if (index >= 0 && index < ncells) {
-            this.cell_elements().eq(index).before(cell.element);
+    Notebook.prototype.select_prev = function () {
+        var index = this.get_selected_index();
+        if (index !== null && index >= 0 && (index-1) < this.ncells()) {
+            this.select(index-1);
         };
-        this.dirty = true;
         return this;
     };
 
 
+    // Cell movement
+
     Notebook.prototype.move_cell_up = function (index) {
-        var i = index || this.selected_index();
+        var i = this.index_or_selected();
         if (i !== null && i < this.ncells() && i > 0) {
-            var pivot = this.cell_elements().eq(i-1);
-            var tomove = this.cell_elements().eq(i);
+            var pivot = this.get_cell_element(i-1);
+            var tomove = this.get_cell_element(i);
             if (pivot !== null && tomove !== null) {
                 tomove.detach();
                 pivot.before(tomove);
                 this.select(i-1);
             };
         };
         this.dirty = true;
         return this;
     };
 
 
     Notebook.prototype.move_cell_down = function (index) {
-        var i = index || this.selected_index();
+        var i = this.index_or_selected();
         if (i !== null && i < (this.ncells()-1) && i >= 0) {
-            var pivot = this.cell_elements().eq(i+1);
-            var tomove = this.cell_elements().eq(i);
+            var pivot = this.get_cell_element(i+1);
+            var tomove = this.get_cell_element(i);
             if (pivot !== null && tomove !== null) {
                 tomove.detach();
                 pivot.after(tomove);
                 this.select(i+1);
             };
         };
         this.dirty = true;
         return this;
     };
 
 
     Notebook.prototype.sort_cells = function () {
+        // This is not working right now. Calling this will actually crash
+        // the browser. I think there is an infinite loop in here...
         var ncells = this.ncells();
-        var sindex = this.selected_index();
+        var sindex = this.get_selected_index();
         var swapped;
         do {
             swapped = false;
             for (var i=1; i<ncells; i++) {
-                current = this.cell_elements().eq(i).data("cell");
-                previous = this.cell_elements().eq(i-1).data("cell");
+                current = this.get_cell(i);
+                previous = this.get_cell(i-1);
                 if (previous.input_prompt_number > current.input_prompt_number) {
                     this.move_cell_up(i);
                     swapped = true;
                 };
             };
         } while (swapped);
         this.select(sindex);
         return this;
     };
 
+    // Insertion, deletion.
 
-    Notebook.prototype.insert_code_cell_above = function (index) {
-        // TODO: Bounds check for i
+    Notebook.prototype.delete_cell = function (index) {
         var i = this.index_or_selected(index);
-        var cell = new IPython.CodeCell(this);
-        cell.set_input_prompt();
-        this.insert_cell_above(cell, i);
-        this.select(this.find_cell_index(cell));
-        return cell;
+        if (this.is_valid_cell_index(i)) {
+            var ce = this.get_cell_element(i);
+            ce.remove();
+            if (i === (this.ncells())) {
+                this.select(i-1);
+            } else {
+                this.select(i);
+            };
+            this.dirty = true;
+        };
+        return this;
     };
 
 
-    Notebook.prototype.insert_code_cell_below = function (index) {
-        // TODO: Bounds check for i
-        var i = this.index_or_selected(index);
+    Notebook.prototype.insert_cell_below = function (type, index) {
+        // type = ('code','html','markdown')
+        // index = cell index or undefined to insert below selected
+        index = this.index_or_selected(index);
+        if (this.ncells() === 0 || this.is_valid_cell_index(index)) {
+            var cell = null;
+            if (type === 'code') {
         var cell = new IPython.CodeCell(this);
         cell.set_input_prompt();
-        this.insert_cell_below(cell, i);
-        this.select(this.find_cell_index(cell));
-        return cell;
-    };
-
-
-    Notebook.prototype.insert_html_cell_above = function (index) {
-        // TODO: Bounds check for i
-        var i = this.index_or_selected(index);
-        var cell = new IPython.HTMLCell(this);
+            } else if (type === 'markdown') {
+                var cell = new IPython.MarkdownCell(this);
         cell.config_mathjax();
-        this.insert_cell_above(cell, i);
-        this.select(this.find_cell_index(cell));
-        return cell;
-    };
-
-
-    Notebook.prototype.insert_html_cell_below = function (index) {
-        // TODO: Bounds check for i
-        var i = this.index_or_selected(index);
+            } else if (type === 'html') {
         var cell = new IPython.HTMLCell(this);
         cell.config_mathjax();
-        this.insert_cell_below(cell, i);
-        this.select(this.find_cell_index(cell));
-        return cell;
     };
-
-
-    Notebook.prototype.insert_markdown_cell_above = function (index) {
-        // TODO: Bounds check for i
-        var i = this.index_or_selected(index);
-        var cell = new IPython.MarkdownCell(this);
-        cell.config_mathjax();
-        this.insert_cell_above(cell, i);
+            if (cell !== null) {
+                if (this.ncells() === 0) {
+                    this.element.find('div.end_space').before(cell.element);
+                    this.select(this.find_cell_index(cell));
+                    this.dirty = true;
+                } else if (this.is_valid_cell_index(index)) {
+                    this.get_cell_element(index).after(cell.element);
         this.select(this.find_cell_index(cell));
+                    this.dirty = true;
+                };
         return cell;
     };
+        };
+    };
 
 
-    Notebook.prototype.insert_markdown_cell_below = function (index) {
-        // TODO: Bounds check for i
-        var i = this.index_or_selected(index);
+    Notebook.prototype.insert_cell_above = function (type, index) {
+        // type = ('code','html','markdown')
+        // index = cell index or undefined to insert above selected
+        index = this.index_or_selected(index);
+        if (this.ncells() === 0 || this.is_valid_cell_index(index)) {
+            var cell = null;
+            if (type === 'code') {
+                var cell = new IPython.CodeCell(this);
+                cell.set_input_prompt();
+            } else if (type === 'markdown') {
         var cell = new IPython.MarkdownCell(this);
         cell.config_mathjax();
-        this.insert_cell_below(cell, i);
+            } else if (type === 'html') {
+                var cell = new IPython.HTMLCell(this);
+                cell.config_mathjax();
+            };
+            if (cell !== null) {
+                if (this.ncells() === 0) {
+                    this.element.find('div.end_space').before(cell.element);
+                    this.select(this.find_cell_index(cell));
+                    this.dirty = true;
+                } else if (this.is_valid_cell_index(index)) {
+                    this.get_cell_element(index).before(cell.element);
         this.select(this.find_cell_index(cell));
+                    this.dirty = true;
+                };
         return cell;
     };
+        };
+    };
 
 
     Notebook.prototype.to_code = function (index) {
-        // TODO: Bounds check for i
         var i = this.index_or_selected(index);
-        var source_element = this.cell_elements().eq(i);
+        if (this.is_valid_cell_index(i)) {
+            var source_element = this.get_cell_element(i);
         var source_cell = source_element.data("cell");
         if (!(source_cell instanceof IPython.CodeCell)) {
-            this.insert_code_cell_below(i);
-            var target_cell = this.cells()[i+1];
+                target_cell = this.insert_cell_below('code',i);
             var text = source_cell.get_text();
             if (text === source_cell.placeholder) {
                 text = '';
             }
             target_cell.set_text(text);
             source_element.remove();
             target_cell.select();
         };
         this.dirty = true;
     };
+    };
 
 
     Notebook.prototype.to_markdown = function (index) {
-        // TODO: Bounds check for i
         var i = this.index_or_selected(index);
-        var source_element = this.cell_elements().eq(i);
+        if (this.is_valid_cell_index(i)) {
+            var source_element = this.get_cell_element(i);
         var source_cell = source_element.data("cell");
         var target_cell = null;
         if (!(source_cell instanceof IPython.MarkdownCell)) {
-            this.insert_markdown_cell_below(i);
-            target_cell = this.cells()[i+1];
+                target_cell = this.insert_cell_below('markdown',i);
             var text = source_cell.get_text();
             if (text === source_cell.placeholder) {
                 text = target_cell.placeholder;
             };
             if (target_cell !== null) {
                 if (text === "") {text = target_cell.placeholder;};
                 // The edit must come before the set_text.
                 target_cell.edit();
                 target_cell.set_text(text);
                 source_element.remove();
                 target_cell.select();
             }
             this.dirty = true;
         };
     };
+    };
 
 
     Notebook.prototype.to_html = function (index) {
-        // TODO: Bounds check for i
         var i = this.index_or_selected(index);
-        var source_element = this.cell_elements().eq(i);
+        if (this.is_valid_cell_index(i)) {
+            var source_element = this.get_cell_element(i);
         var source_cell = source_element.data("cell");
         var target_cell = null;
         if (!(source_cell instanceof IPython.HTMLCell)) {
-            this.insert_html_cell_below(i);
-            target_cell = this.cells()[i+1];
+                target_cell = this.insert_cell_below('html',i);
             var text = source_cell.get_text();
             if (text === source_cell.placeholder) {
                 text = target_cell.placeholder;
             };
             if (target_cell !== null) {
                 if (text === "") {text = target_cell.placeholder;};
                 // The edit must come before the set_text.
                 target_cell.edit();
                 target_cell.set_text(text);
                 source_element.remove();
                 target_cell.select();
             }
             this.dirty = true;
         };
     };
+    };
 
 
-    // Copy/Paste/Merge/Split
+    // Cut/Copy/Paste
 
     Notebook.prototype.enable_paste = function () {
         var that = this;
         if (!this.paste_enabled) {
             $('#paste_cell').removeClass('ui-state-disabled')
                 .on('click', function () {that.paste_cell();});
             $('#paste_cell_above').removeClass('ui-state-disabled')
                 .on('click', function () {that.paste_cell_above();});
             $('#paste_cell_below').removeClass('ui-state-disabled')
                 .on('click', function () {that.paste_cell_below();});
             this.paste_enabled = true;
         };
     };
 
 
     Notebook.prototype.disable_paste = function () {
         if (this.paste_enabled) {
             $('#paste_cell').addClass('ui-state-disabled').off('click');
             $('#paste_cell_above').addClass('ui-state-disabled').off('click');
             $('#paste_cell_below').addClass('ui-state-disabled').off('click');
             this.paste_enabled = false;
         };
     };
 
 
     Notebook.prototype.cut_cell = function () {
         this.copy_cell();
         this.delete_cell();
     }
 
     Notebook.prototype.copy_cell = function () {
-        var cell = this.selected_cell();
+        var cell = this.get_selected_cell();
         this.clipboard = cell.toJSON();
         this.enable_paste();
     };
 
 
     Notebook.prototype.paste_cell = function () {
         if (this.clipboard !== null && this.paste_enabled) {
             var cell_data = this.clipboard;
-            if (cell_data.cell_type == 'code') {
-                new_cell = this.insert_code_cell_above();
-            } else if (cell_data.cell_type === 'html') {
-                new_cell = this.insert_html_cell_above();
-            } else if (cell_data.cell_type === 'markdown') {
-                new_cell = this.insert_markdown_cell_above();
-            };
+            var new_cell = this.insert_cell_above(cell_data.cell_type);
             new_cell.fromJSON(cell_data);
-            this.select_next();
-            this.delete_cell();
+            old_cell = this.get_next_cell(new_cell);
+            this.delete_cell(this.find_cell_index(old_cell));
+            this.select(this.find_cell_index(new_cell));
         };
     };
 
 
     Notebook.prototype.paste_cell_above = function () {
         if (this.clipboard !== null && this.paste_enabled) {
             var cell_data = this.clipboard;
-            if (cell_data.cell_type == 'code') {
-                new_cell = this.insert_code_cell_above();
-            } else if (cell_data.cell_type === 'html') {
-                new_cell = this.insert_html_cell_above();
-            } else if (cell_data.cell_type === 'markdown') {
-                new_cell = this.insert_markdown_cell_above();
-            };
+            var new_cell = this.insert_cell_above(cell_data.cell_type);
             new_cell.fromJSON(cell_data);
         };
     };
 
 
     Notebook.prototype.paste_cell_below = function () {
         if (this.clipboard !== null && this.paste_enabled) {
             var cell_data = this.clipboard;
-            if (cell_data.cell_type == 'code') {
-                new_cell = this.insert_code_cell_below();
-            } else if (cell_data.cell_type === 'html') {
-                new_cell = this.insert_html_cell_below();
-            } else if (cell_data.cell_type === 'markdown') {
-                new_cell = this.insert_markdown_cell_below();
-            };
+            var new_cell = this.insert_cell_below(cell_data.cell_type);
             new_cell.fromJSON(cell_data);
         };
     };
 
 
+    // Split/merge
+
     Notebook.prototype.split_cell = function () {
         // Todo: implement spliting for other cell types.
-        var cell = this.selected_cell();
+        var cell = this.get_selected_cell();
         if (cell instanceof IPython.CodeCell) {
             var cursor = cell.code_mirror.getCursor();
             var last_line_num = cell.code_mirror.lineCount()-1;
             var last_line_len = cell.code_mirror.getLine(last_line_num).length;
             var end = {line:last_line_num, ch:last_line_len}
             var texta = cell.code_mirror.getRange({line:0,ch:0}, cursor);
             var textb = cell.code_mirror.getRange(cursor, end);
             texta = texta.replace(/^\n+/, '').replace(/\n+$/, '');
             textb = textb.replace(/^\n+/, '').replace(/\n+$/, '');
             cell.set_text(texta);
-            var new_cell = this.insert_code_cell_below();
+            var new_cell = this.insert_cell_below('code');
             new_cell.set_text(textb);
         };
     };
 
 
     Notebook.prototype.merge_cell_above = function () {
         // Todo: implement merging for other cell types.
-        var cell = this.selected_cell();
-        var index = this.selected_index();
+        var cell = this.get_selected_cell();
+        var index = this.get_selected_index();
         if (index > 0) {
-            upper_cell = this.cells()[index-1];
-            lower_cell = this.cells()[index];
+            upper_cell = this.get_cell(index-1);
+            lower_cell = this.get_cell(index);
             if (upper_cell instanceof IPython.CodeCell && lower_cell instanceof IPython.CodeCell) {
                 upper_text = upper_cell.get_text();
                 lower_text = lower_cell.get_text();
                 lower_cell.set_text(upper_text+'\n'+lower_text);
                 this.delete_cell(index-1);
             };
         };
     };
 
 
     Notebook.prototype.merge_cell_below = function () {
         // Todo: implement merging for other cell types.
-        var cell = this.selected_cell();
-        var index = this.selected_index();
+        var cell = this.get_selected_cell();
+        var index = this.get_selected_index();
         if (index < this.ncells()-1) {
-            upper_cell = this.cells()[index];
-            lower_cell = this.cells()[index+1];
+            upper_cell = this.get_cell(index);
+            lower_cell = this.get_cell(index+1);
             if (upper_cell instanceof IPython.CodeCell && lower_cell instanceof IPython.CodeCell) {
                 upper_text = upper_cell.get_text();
                 lower_text = lower_cell.get_text();
                 upper_cell.set_text(upper_text+'\n'+lower_text);
                 this.delete_cell(index+1);
             };
         };
     };
 
     // Cell collapsing and output clearing
 
     Notebook.prototype.collapse = function (index) {
         var i = this.index_or_selected(index);
-        this.cells()[i].collapse();
+        this.get_cell(i).collapse();
         this.dirty = true;
     };
 
 
     Notebook.prototype.expand = function (index) {
         var i = this.index_or_selected(index);
-        this.cells()[i].expand();
+        this.get_cell(i).expand();
         this.dirty = true;
     };
 
 
     Notebook.prototype.toggle_output = function (index) {
         var i = this.index_or_selected(index);
-        this.cells()[i].toggle_output();
+        this.get_cell(i).toggle_output();
         this.dirty = true;
     };
 
 
     Notebook.prototype.set_timebeforetooltip = function (time) {
         this.time_before_tooltip = time;
     };
 
     Notebook.prototype.set_tooltipontab = function (state) {
         this.tooltip_on_tab = state;
     };
 
     Notebook.prototype.set_smartcompleter = function (state) {
         this.smart_completer = state;
     };
 
     Notebook.prototype.set_autoindent = function (state) {
-        var cells = this.cells();
+        var cells = this.get_cells();
         len = cells.length;
         for (var i=0; i<len; i++) {
             cells[i].set_autoindent(state);
         };
     };
 
 
     Notebook.prototype.clear_all_output = function () {
         var ncells = this.ncells();
-        var cells = this.cells();
+        var cells = this.get_cells();
         for (var i=0; i<ncells; i++) {
             if (cells[i] instanceof IPython.CodeCell) {
                 cells[i].clear_output(true,true,true);
             }
         };
         this.dirty = true;
     };
 
     // Other cell functions: line numbers, ...
 
     Notebook.prototype.cell_toggle_line_numbers = function() {
-        this.selected_cell().toggle_line_numbers();
+        this.get_selected_cell().toggle_line_numbers();
     };
 
     // Kernel related things
 
     Notebook.prototype.start_kernel = function () {
         this.kernel = new IPython.Kernel();
         var notebook_id = IPython.save_widget.get_notebook_id();
         this.kernel.start(notebook_id, $.proxy(this.kernel_started, this));
     };
 
 
     Notebook.prototype.restart_kernel = function () {
         var that = this;
         var notebook_id = IPython.save_widget.get_notebook_id();
 
         var dialog = $('<div/>');
         dialog.html('Do you want to restart the current kernel?  You will lose all variables defined in it.');
         $(document).append(dialog);
         dialog.dialog({
             resizable: false,
             modal: true,
             title: "Restart kernel or continue running?",
             closeText: '',
             buttons : {
                 "Restart": function () {
                     that.kernel.restart($.proxy(that.kernel_started, that));
                     $(this).dialog('close');
                 },
                 "Continue running": function () {
                     $(this).dialog('close');
                 }
             }
         });
     };
 
 
     Notebook.prototype.kernel_started = function () {
         console.log("Kernel started: ", this.kernel.kernel_id);
         this.kernel.shell_channel.onmessage = $.proxy(this.handle_shell_reply,this);
         this.kernel.iopub_channel.onmessage = $.proxy(this.handle_iopub_reply,this);
     };
 
 
     Notebook.prototype.handle_shell_reply = function (e) {
         reply = $.parseJSON(e.data);
         var header = reply.header;
         var content = reply.content;
         var msg_type = header.msg_type;
         // console.log(reply);
         var cell = this.cell_for_msg(reply.parent_header.msg_id);
         if (msg_type === "execute_reply") {
             cell.set_input_prompt(content.execution_count);
             cell.element.removeClass("running");
             this.dirty = true;
         } else if (msg_type === "complete_reply") {
             cell.finish_completing(content.matched_text, content.matches);
         } else if (msg_type === "object_info_reply"){
             //console.log('back from object_info_request : ')
             rep = reply.content;
             if(rep.found)
             {
                 cell.finish_tooltip(rep);
             }
         } else {
           //console.log("unknown reply:"+msg_type);
         }
         // when having a rely from object_info_reply,
         // no payload so no nned to handle it
         if(typeof(content.payload)!='undefined') {
             var payload = content.payload || [];
             this.handle_payload(cell, payload);
         }
     };
 
 
     Notebook.prototype.handle_payload = function (cell, payload) {
         var l = payload.length;
         for (var i=0; i<l; i++) {
             if (payload[i].source === 'IPython.zmq.page.page') {
                 if (payload[i].text.trim() !== '') {
                     IPython.pager.clear();
                     IPython.pager.expand();
                     IPython.pager.append_text(payload[i].text);
                 }
             } else if (payload[i].source === 'IPython.zmq.zmqshell.ZMQInteractiveShell.set_next_input') {
                 var index = this.find_cell_index(cell);
-                var new_cell = this.insert_code_cell_below(index);
+                var new_cell = this.insert_cell_below('code',index);
                 new_cell.set_text(payload[i].text);
                 this.dirty = true;
             }
         };
     };
 
 
     Notebook.prototype.handle_iopub_reply = function (e) {
         reply = $.parseJSON(e.data);
         var content = reply.content;
         // console.log(reply);
         var msg_type = reply.header.msg_type;
         var cell = this.cell_for_msg(reply.parent_header.msg_id);
         if (msg_type !== 'status' && !cell){
             // message not from this notebook, but should be attached to a cell
             console.log("Received IOPub message not caused by one of my cells");
             console.log(reply);
             return;
         }
         var output_types = ['stream','display_data','pyout','pyerr'];
         if (output_types.indexOf(msg_type) >= 0) {
             this.handle_output(cell, msg_type, content);
         } else if (msg_type === 'status') {
             if (content.execution_state === 'busy') {
                 IPython.kernel_status_widget.status_busy();
             } else if (content.execution_state === 'idle') {
                 IPython.kernel_status_widget.status_idle();
             } else if (content.execution_state === 'dead') {
                 this.handle_status_dead();
             };
         } else if (msg_type === 'clear_output') {
             cell.clear_output(content.stdout, content.stderr, content.other);
         };
     };
 
 
     Notebook.prototype.handle_status_dead = function () {
         var that = this;
         this.kernel.stop_channels();
         var dialog = $('<div/>');
         dialog.html('The kernel has died, would you like to restart it? If you do not restart the kernel, you will be able to save the notebook, but running code will not work until the notebook is reopened.');
         $(document).append(dialog);
         dialog.dialog({
             resizable: false,
             modal: true,
             title: "Dead kernel",
             buttons : {
                 "Restart": function () {
                     that.start_kernel();
                     $(this).dialog('close');
                 },
                 "Continue running": function () {
                     $(this).dialog('close');
                 }
             }
         });
     };
 
 
     Notebook.prototype.handle_output = function (cell, msg_type, content) {
         var json = {};
         json.output_type = msg_type;
         if (msg_type === "stream") {
             json.text = utils.fixConsole(content.data);
             json.stream = content.name;
         } else if (msg_type === "display_data") {
             json = this.convert_mime_types(json, content.data);
         } else if (msg_type === "pyout") {
             json.prompt_number = content.execution_count;
             json = this.convert_mime_types(json, content.data);
         } else if (msg_type === "pyerr") {
             json.ename = content.ename;
             json.evalue = content.evalue;
             var traceback = [];
             for (var i=0; i<content.traceback.length; i++) {
                 traceback.push(utils.fixConsole(content.traceback[i]));
             }
             json.traceback = traceback;
         };
         cell.append_output(json);
         this.dirty = true;
     };
 
 
     Notebook.prototype.convert_mime_types = function (json, data) {
         if (data['text/plain'] !== undefined) {
             json.text = utils.fixConsole(data['text/plain']);
         };
         if (data['text/html'] !== undefined) {
             json.html = data['text/html'];
         };
         if (data['image/svg+xml'] !== undefined) {
             json.svg = data['image/svg+xml'];
         };
         if (data['image/png'] !== undefined) {
             json.png = data['image/png'];
         };
         if (data['image/jpeg'] !== undefined) {
             json.jpeg = data['image/jpeg'];
         };
         if (data['text/latex'] !== undefined) {
             json.latex = data['text/latex'];
         };
         if (data['application/json'] !== undefined) {
             json.json = data['application/json'];
         };
         if (data['application/javascript'] !== undefined) {
             json.javascript = data['application/javascript'];
         }
         return json;    
     };
 
 
     Notebook.prototype.execute_selected_cell = function (options) {
         // add_new: should a new cell be added if we are at the end of the nb
         // terminal: execute in terminal mode, which stays in the current cell
         default_options = {terminal: false, add_new: true};
         $.extend(default_options, options);
         var that = this;
-        var cell = that.selected_cell();
+        var cell = that.get_selected_cell();
         var cell_index = that.find_cell_index(cell);
         if (cell instanceof IPython.CodeCell) {
             cell.clear_output(true, true, true);
             cell.set_input_prompt('*');
             cell.element.addClass("running");
             var code = cell.get_text();
             var msg_id = that.kernel.execute(cell.get_text());
             that.msg_cell_map[msg_id] = cell.cell_id;
         } else if (cell instanceof IPython.HTMLCell) {
             cell.render();
         }
         if (default_options.terminal) {
             cell.select_all();
         } else {
             if ((cell_index === (that.ncells()-1)) && default_options.add_new) {
-                that.insert_code_cell_below();
+                that.insert_cell_below('code');
                 // If we are adding a new cell at the end, scroll down to show it.
                 that.scroll_to_bottom();
             } else {
                 that.select(cell_index+1);
             };
         };
         this.dirty = true;
     };
 
 
     Notebook.prototype.execute_all_cells = function () {
         var ncells = this.ncells();
         for (var i=0; i<ncells; i++) {
             this.select(i);
-            this.execute_selected_cell({add_new:false});
+            this.execute_get_selected_cell({add_new:false});
         };
         this.scroll_to_bottom();
     };
 
 
     Notebook.prototype.request_tool_tip = function (cell,func) {
         // Feel free to shorten this logic if you are better
         // than me in regEx
         // basicaly you shoul be able to get xxx.xxx.xxx from 
         // something(range(10), kwarg=smth) ; xxx.xxx.xxx( firstarg, rand(234,23), kwarg1=2, 
         // remove everything between matchin bracket (need to iterate)
         matchBracket = /\([^\(\)]+\)/g;
         oldfunc = func;
         func = func.replace(matchBracket,"");
         while( oldfunc != func )
         {
         oldfunc = func;
         func = func.replace(matchBracket,"");
         }
         // remove everythin after last open bracket
         endBracket = /\([^\(]*$/g;
         func = func.replace(endBracket,"");
         var re = /[a-zA-Z._]+$/g;
         var msg_id = this.kernel.object_info_request(re.exec(func));
         if(typeof(msg_id)!='undefined'){
             this.msg_cell_map[msg_id] = cell.cell_id;
             }
     };
 
     Notebook.prototype.complete_cell = function (cell, line, cursor_pos) {
         var msg_id = this.kernel.complete(line, cursor_pos);
         this.msg_cell_map[msg_id] = cell.cell_id;
     };
 
     // Persistance and loading
 
 
     Notebook.prototype.fromJSON = function (data) {
         var ncells = this.ncells();
         var i;
         for (i=0; i<ncells; i++) {
             // Always delete cell 0 as they get renumbered as they are deleted.
             this.delete_cell(0);
         };
         // Save the metadata
         this.metadata = data.metadata;
         // Only handle 1 worksheet for now.
         var worksheet = data.worksheets[0];
         if (worksheet !== undefined) {
             var new_cells = worksheet.cells;
             ncells = new_cells.length;
             var cell_data = null;
             var new_cell = null;
             for (i=0; i<ncells; i++) {
                 cell_data = new_cells[i];
-                if (cell_data.cell_type == 'code') {
-                    new_cell = this.insert_code_cell_below();
-                    new_cell.fromJSON(cell_data);
-                } else if (cell_data.cell_type === 'html') {
-                    new_cell = this.insert_html_cell_below();
+                new_cell = this.insert_cell_below(cell_data.cell_type);
                     new_cell.fromJSON(cell_data);
-                } else if (cell_data.cell_type === 'markdown') {
-                    new_cell = this.insert_markdown_cell_below();
-                    new_cell.fromJSON(cell_data);
-                };
             };
         };
     };
 
 
     Notebook.prototype.toJSON = function () {
-        var cells = this.cells();
+        var cells = this.get_cells();
         var ncells = cells.length;
         cell_array = new Array(ncells);
         for (var i=0; i<ncells; i++) {
             cell_array[i] = cells[i].toJSON();
         };
         data = {
             // Only handle 1 worksheet for now.
             worksheets : [{cells:cell_array}],
             metadata : this.metadata
         };
         return data;
     };
 
     Notebook.prototype.save_notebook = function () {
         if (IPython.save_widget.test_notebook_name()) {
             var notebook_id = IPython.save_widget.get_notebook_id();
             var nbname = IPython.save_widget.get_notebook_name();
             // We may want to move the name/id/nbformat logic inside toJSON?
             var data = this.toJSON();
             data.metadata.name = nbname;
             data.nbformat = 2;
             // We do the call with settings so we can set cache to false.
             var settings = {
                 processData : false,
                 cache : false,
                 type : "PUT",
                 data : JSON.stringify(data),
                 headers : {'Content-Type': 'application/json'},
                 success : $.proxy(this.notebook_saved,this),
                 error : $.proxy(this.notebook_save_failed,this)
             };
             IPython.save_widget.status_saving();
             var url = $('body').data('baseProjectUrl') + 'notebooks/' + notebook_id;
             $.ajax(url, settings);
         };
     };
 
 
     Notebook.prototype.notebook_saved = function (data, status, xhr) {
         this.dirty = false;
         IPython.save_widget.notebook_saved();
         IPython.save_widget.status_last_saved();
     };
 
 
     Notebook.prototype.notebook_save_failed = function (xhr, status, error_msg) {
         IPython.save_widget.status_save_failed();
     };
 
 
     Notebook.prototype.load_notebook = function (callback) {
         var that = this;
         var notebook_id = IPython.save_widget.get_notebook_id();
         // We do the call with settings so we can set cache to false.
         var settings = {
             processData : false,
             cache : false,
             type : "GET",
             dataType : "json",
             success : function (data, status, xhr) {
                 that.notebook_loaded(data, status, xhr);
                 if (callback !== undefined) {
                     callback();
                 };
             }
         };
         IPython.save_widget.status_loading();
         var url = $('body').data('baseProjectUrl') + 'notebooks/' + notebook_id;
         $.ajax(url, settings);
     };
 
 
     Notebook.prototype.notebook_loaded = function (data, status, xhr) {
         var allowed = xhr.getResponseHeader('Allow');
         this.fromJSON(data);
         if (this.ncells() === 0) {
-            this.insert_code_cell_below();
+            this.insert_cell_below('code');
         };
         IPython.save_widget.status_last_saved();
         IPython.save_widget.set_notebook_name(data.metadata.name);
         this.dirty = false;
         if (! this.read_only) {
             this.start_kernel();
         }
         // fromJSON always selects the last cell inserted. We need to wait
         // until that is done before scrolling to the top.
         setTimeout(function () {
             IPython.notebook.select(0);
             IPython.notebook.scroll_to_top();
         }, 50);
     };
 
     IPython.Notebook = Notebook;
 
 
     return IPython;
 
 }(IPython));