Word document generator? (Open source)
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I have looked around for an open source document generation libraries but haven't really found anything.

I am looking for an easy to use word document generation tool for generating documents from templates. 

The main features that I need are:

 - Merge fields for text.
 - Merge fields for images.
 - Conversion of generated documents to pdf.

What I want to do is be able to create word document templates with merge fields for text and images and then dynamically merge data and images into the templates. After a document has been generated I also require the ability to convert it to pdf.

Preferably I would like to use a library or a set of libraries that are open source. Or something where I can buy the source code.

Mono support is also required.

Is there any good libraries out there with these features?