Creating Text Editor in Unity

Hi Guys, I am creating an app like text editor (same as Unity’s question editor where I typed this question), with features bold,italic,underline,font,color,alignment etc.

My problems are-

I am unable to get selected text from
Unable to get cursor position in Text Area
How can I put some characters middle of the text, suppose the text is “EDUATION” and it should be “EDUCATION” so I need to insert “C” after “U” how can I achieve this without deleting “ATION”?
How can I make perticular text BOLD by selecting the text and press on bold button(for example see above line in this question where C U etc are bold)
If you know any plugin to do this so please let me know, I will be very thankful to you.

Thanks!

Have you even checked the scripting reference for Unity before you posted your question?

all ways of adressing and getting information from 3dtext is in the documentation

http://docs.unity3d.com/Documentation/ScriptReference/GUIText.html

Yes I have checked it, and its not my solution, please read my question again.

My requirement is how to selected a part of a word(text) and make bold selected part only.