This is C# coding test app.

• Common application architecture in Reactive Style
• Basic simple WPF UI
• 3 simple plugins for csv, txt and xml parsing
• Basic Unit tests
• Simple config in App.config

• Processing files is moved to "Processed" folder to avoid double processing. Requirements doesn't cover this case.
• I batch(buffer) input file content per 100 lines, to IO performance and reduce thread overhead

• File can be open due to processing, need to skip it
• Logging. Because logging depends on you local preferences and styles. I maked critical section for logging as TODO
• Plugins can be in Reactive Style too, with async reading. I skipped this for simplicity reason
• File content parsing as datetime, int and so on. Requirements doesn't cover this case and for simplicity reason
• Nice UI
• 99.9% unit test coverage and input with errors and mistakes
• Unit tests for directory watcher
• Coding style, method cases and other things let's leave for haters