Create an assembly graph with the reference as template.
Take each read and match it to graph segments. Add new nodes if a part does not match.
Keep track how many reads support each path segment and determine the most likely paths.
Build haplotype sequences from likely paths.
For an active region:
Create an assembly graph with the reference as template. Take each read and match it to graph segments. Add new nodes if a part does not match. Keep track how many reads support each path segment and determine the most likely paths. Build haplotype sequences from likely paths.