#!/usr/bin/env python

def parse_keyfile(f, d, constructor = lambda x: x):
    for line in f:
        kv = [s.strip() for s in line.split(':')]
        if not len(kv) == 2:
            continue
        d[kv[0]] = constructor(kv[1])

def merge_dicts(d1, d2):
    d = {}
    for k in d1:
        d[k] = (d1[k], d2[k] if k in d2 else None)
    for k in d2:
        if not k in d:
            d[k] = (None, d2[k])
    return d

def main(fname1, fname2, verbose = True):
    if verbose:
        print('opening ' + fname1 + ' as base key/value store')
        print('opening ' + fname2 + ' as target key/value store')

    d1 = {}
    d2 = {}
    with open(fname1, 'rt') as f1:
        parse_keyfile(f1, d1, int)
    with open(fname2, 'rt') as f2:
        parse_keyfile(f2, d2, int)
    
    tot1 = sum(d1.values())
    tot2 = sum(d2.values())

    if verbose:
        print('  ' + fname1 + ': ' + str(len(d1)) + ', total ' + str(tot1))
        print('  ' + fname2 + ': ' + str(len(d2)) + ', total ' + str(tot2))

    d_merged = merge_dicts(d1, d2)

    ratios = {}
    only_1 = {}
    only_2 = {}
    for k in d_merged:
        (v1, v2) = d_merged[k]
        if v1 is None:
            only_2[k] = v2
        elif v2 is None:
            only_1[k] = v1
        else:
            ratios[k] = float(v2 * tot1) / float(v1 * tot2)

    print('shared: ' + str(len(ratios)))
    for k in sorted(ratios, key=lambda x: d2[x], reverse=True):
        print('  ' + k + ': ' + str(d2[k]) + '/' +
              str(d1[k]) + ' (' + str(ratios[k]) + ')')
    print('')

    print('1 only: ' + str(len(only_1)))
    for k in sorted(only_1, key=lambda x: d1[x], reverse=True):
        print('  ' + k + ': ' + str(d1[k]))
    print('')

    print('2 only: ' + str(len(only_2)))
    for k in sorted(only_2, key=lambda x: d2[x], reverse=True):
        print('  ' + k + ': ' + str(d2[k]))
    print('')

if __name__ == '__main__':
    
    import argparse
    parser = argparse.ArgumentParser()
    
    parser.add_argument('file1', #nargs='?'. default=None,
                        help='base key file to diff against')
    parser.add_argument('file2', nargs='?', default=None,
                        help='other file to compare against the baseline')
    parser.add_argument('-v', '--verbose', action='store_true', 
                        help='verbose output')

    args = parser.parse_args()
    main(args.file1, args.file2, verbose=args.verbose)
    exit(0)