#!/usr/bin/env python3
import os
import sys

def reduce_string(string, min_len):
    versions = []
    for i in range(min_len, len(string) + 1):
        versions.append(string[:i])
    versions.reverse()
    return versions

def maximum_common_string(listofstrings, min_len):
    '''compare items of a list, grouping by common strings, keeping groups as small as possible'''
    for filepath in listofstrings:
        base = os.path.splitext(os.path.basename(filepath))[0]
        string_versions = reduce_string(base, min_len)
        for string in string_versions:
            common_strings = [x for x in listofstrings if string in x]
            if len(common_strings) > 2:
                return (string, common_strings)
    return

def safe_move(files, directory):
    if not os.path.exists(directory):
        os.makedirs(directory)
    for item in files:
        newPath = os.path.join(directory, item)
        if not os.path.exists(newPath):
            currentPath = os.path.join(os.path.dirname(directory), item)
            print(f"moving {os.path.join(os.path.dirname(directory), item)} to {os.path.join(directory, item)}")
            os.rename(currentPath, newPath)
        else:
            print("file exists, skipping")
    return

def main():
    if len(sys.argv) > 1:
        workingPath = os.path.abspath(sys.argv[1])
    else:
        print("need directory")
        sys.exit()
    filepaths = os.listdir(workingPath)
    while strings := maximum_common_string(filepaths, 6):
        for x in strings[1]:
            filepaths.pop(filepaths.index(x))
        safe_move(strings[1], os.path.join(workingPath, strings[0]))
    return

if __name__ == "__main__":
    main()