#!/usr/bin/env perl
use 5.014;
use warnings;
use Encode qw/decode_utf8 encode_utf8/;
use Unicode::Normalize qw/NFC/;
use File::Basename qw/basename dirname/;
use File::Copy qw/move/;
use File::Spec;

for my $file (@ARGV) {
    die "file not found: $file\n" unless -e $file;

    my $dir = dirname $file;
    opendir my $dh, $dir or die $!;
    my $fname = decode_utf8 basename $file;

    # readdir しないと 生のファイル名が取れない
    # (NFC/NFDどちらでもファイルの実体を解決できるため)
    while (my $f = readdir $dh) {
        my $fbase = decode_utf8 $f;
        # NFC subroutine expects perl string
        if (NFC($fname) eq NFC($fbase)) {
            try_move( File::Spec->catfile($dir, $f) );
        }
    }
}

sub try_move {
    my $file = shift;
    $file = decode_utf8 $file;
    my $nfc = NFC($file);
    if ($nfc ne $file) {
        my $raw_nfc = encode_utf8 $nfc;
        move($file, $nfc) or die "Move $raw_nfc failed: $!\n";
        printf "moved: %s", $raw_nfc;
    }
}