Editor with widgets

Propose

The target of the article is to specify the behavior of Mozilla editor in case of using it in containers with contentEditable=true and with widgets inside of the editable area.

Application area

Development gecko based WYSIWYG XForms editors. An example of WYSIWYG XForms editor is Microsoft Office InfoPath.
Editor of not fully structured forms.

Необходимость в таких формах возникает при формировании Clinical Documents.

The specification is corresponding with behavior of Microsoft Internet Explorer 6,7,8 and Microsoft Office InfoPath.

Examples

Medical Document
Simple WYSIWYG XForms editors

Widgets in containers with contentEditable attribute

The common approach - the behavior of widgets is the same with the HTML specification. But in HTML widgets are in the static place and in the editor widgets is a part of editing text, it is possible to cut, copy and paste widgets by clipboard.

Common behavior for all type of widgets in editing fields

if the caret is directly before/after the widget then instead of next right/left caret's position the focus is on the widget.
if the caret is directly before/after a widget then pressing of delete/backspace key is removing the widget
if the widget has focus then pressing of delete/backspace key is removing the widget
widget has to receive all events (onclick, onchange etc)
if widget has focus or widget is in the editor's selection then it is possible to copy (cut) the widget to clipboard and paste it to other place of the editing field or other field

SELECT

if the widget has focus then pressing down/up key should change current value of widget's text field from widgets list. When the last/first list's value is achieved then the following pressing up/down key has no affects.
mouse click on widget's text field should move focus to it and open widget's menu
double click should open and close widget's menu

BUTTON

if the button has focus and widget has onclick handler then pressing enter key should perform onlick handler
if button has no focus then mouse click on button should move focus to button
double click on button moves focus to button and performs onclick handler

INPUT type="text"

if caret is directly before/after the text field then pressing right/left key should move caret into widget's text field in the first/last position of the field's content. If the widget's content is larger then text field should be scrolled
if caret is in the first/last position of the field's content then pressing left/right key moves caret to directly before/after the widget.
if caret is in the widget then pressing end/home key should move caret to

the last/first position of the field's content

if caret is in the widget then pressing delete/backspace key can remove only field's content. If content is empty then nothing happens.
mouse click on text field moves focus to widget and moves caret on field's content. If mouse click is on the field but there is no content in this place then the caret moves to the last position of the content.
when the focus leaves the text field then onchange handler should be performed
double click and click on text field should moves the focus to widget

INPUT type="radio"

if the widget has focus then pressing space key sets the value of 'checked' attribute to 'true'
double click and click on the widget moves focus to widget and sets the value of 'checked' attribute to 'true'
if the widget has focus then pressing delete/backspace key the widget should be removed

INPUT type="checkbox"

if the widget has focus then pressing Space key sets the value of 'checked' to inverse value
double click and click on the widget moves focus to widget and sets the value of 'checked' attribute to inverse value
if the widget has focus then pressing Delete/Backspace key the widget should be removed