Redesign unique encoding to int mapping

[dan1994]

I'm not satisfied with the current solution, as it feels awkward and provides no good guarantees that there won't be duplicates.
I have researched a bit and found this post about type maps, so I'll try to redesign using that as a building block.

[dan1994]

Blocked on this issue, since It's hard to find a good design for a two-way conversion (not only type->int but also int->type). For now, will proceed with implementation as if Huffman is the only type of encoding.