Combining .txt files with applescript, shell, sed, grep on Mac Os.

Merging and working on .txt files. Project details: You can make this application with whatever software from xcode to python but it is preferred the use of Applescript. The project must be easily compiled and launched from within Hazel. Application must do the following: merge some .txt files inside a directory choosing some of them following a rule. All files are .txt. All files are incrementally numbered. The resulting .txt must have the content of the requested files plus content coming from some variables and other filenames. A good developer should do this quite fast. Read the file for a full description.