'''List all tags used in current directory and subdirectories.'''

import os
from lib.tagfiles import TagCollection
from lib.dl_editdistance import dameraulevenshtein

def find_similar_tags(tagnames):
    '''Find tag name pairs that have edit distance of 2 or less.'''
    for i, tagname1 in enumerate(tagnames):
        for tagname2 in tagnames[i+1:]:
            if dameraulevenshtein(tagname1, tagname2) <= 2:
                yield (tagname1, tagname2)

def check_files_exist(path, tagcollection):
    '''Check for obscure syntax errors causing links to non-existing files.'''
    for tagname, targets in tagcollection.tags.items():
        for relpath in targets:
            if not os.path.exists(os.path.join(path, relpath)):
                yield tagname, relpath

def main(path, print_all):
    tc = TagCollection()
    tc.import_recursively(path, 'Merkinnat.txt')
    
    if tc.msgs:
        print "Import messages (%d):" % len(tc.msgs)
        for msg in tc.msgs:
            print msg
            print '-' * 20
        print
    
    tagnames = tc.tags.keys()
    tagnames.sort()
    tagnamewidth = max([len(t) for t in tagnames])
    
    if print_all:
        print "Tag name".ljust(tagnamewidth), "Use count"
        use_counts = [(tagname, len(tc.tags[tagname])) for tagname in tagnames]
        use_counts.sort(key = lambda t: t[1])
        for tagname, count in use_counts:
            print tagname.ljust(tagnamewidth), count
        print

    similar = find_similar_tags(tagnames)
    for i, (tag1, tag2) in enumerate(similar):
        if min(len(tc.tags[tag1]), len(tc.tags[tag2])) >= 3:
            continue
        
        if i == 0: print "Similar tags:"
        print repr(tag1).ljust(tagnamewidth), ', '.join(tc.tags[tag1])
        print repr(tag2).ljust(tagnamewidth), ', '.join(tc.tags[tag2])
        print
    
    for tagname, relpath in check_files_exist(path, tc):
        print ("ERROR: file " + relpath + " for tag " + tagname +
            " does not exist!")

if __name__ == '__main__':
    import sys
    main(os.getcwd(), '--all' in sys.argv)