use strict;
use utf8;

my $data_dir_name = q[data/];
my $data2_dir_name = q[data2/];
my $data2_suffix = q[.dat];
my $lock_suffix = q[.lock];

## SEE ALSO: |Makefile|.
my $fallback_file_name = $data2_dir_name . 'fallback' . $data2_suffix;

## SEE ALSO: |Makefile|.
my $patch_file_name = $data2_dir_name . 'modified.txt';

our $UseCVS //= 1;

sub normalize ($) {
  my $s = shift;
  $s =~ s/\s+/ /g;
  $s =~ s/^ //;
  $s =~ s/ $//g;
  return $s;
} # normalize

sub get_hash ($) {
  require Digest::MD5;
  require Encode;
  return Digest::MD5::md5_hex (Encode::encode ('utf8', normalize ($_[0])));
} # get_hash

sub create_pattern1 ($) {
  my $s = quotemeta shift;
  $s =~ s/\\\*/(.+)/g;
  return $s;
} # create_pattern1

sub replace_pattern2 ($@) {
  my $s = shift;
  my @arg = @_;
  $s =~ s/\$(\d+)/$arg[$1 - 1]/g;
  return $s;
} # replace_pattern2

sub read_data_file ($) {
  my $file_name = shift;
  if (-f $file_name) {
    warn "Loading $file_name...\n";
    return do $file_name;
  } else {
    warn "File $file_name not found\n";
    return {};
  }
} # read_data_file

sub write_data_file ($$) {
  my ($file_name, $data) = @_;

  require Data::Dumper;
  local $Data::Dumper::Sortkeys = 1;
  local $Data::Dumper::Useqq = 1;
  local *Data::Dumper::qquote = sub {
    my $s = shift;
    $s =~ s/([\x24\x27\x40\x5C])/sprintf '\x%02X', ord $1/ge;
    return q<qq'> . $s . q<'>;
  }; # Data::Dumper::qquote
  
  my $had_file = -f $file_name;
  open my $file, '>:encoding(utf8)', $file_name or die "$0: $file_name: $!";
  print $file "use utf8;\n";
  print $file Data::Dumper::Dumper ($data);
  close $file;
  unless ($had_file) {
    system_ ('cvs', 'add', $file_name) if $UseCVS;
  }
} # write_data_file

sub hash_to_file_name ($) {
  return $data2_dir_name . substr ($_[0], 0, 2) . $data2_suffix;
} # hash_to_file_name

my $Entry = {};
my $ModifiedHash = {};

sub get_entry ($) {
  my $hash = shift;
  
  my $file_name = hash_to_file_name ($hash);
  unless ($Entry->{$file_name}) {
    $Entry->{$file_name} = read_data_file ($file_name);
  }
  
  if ($Entry->{$file_name}->{exact}->{$hash}) {
    return (0, $Entry->{$file_name}->{exact}->{$hash});
  } elsif ($Entry->{$file_name}->{pattern}->{$hash}) {
    return (1, $Entry->{$file_name}->{pattern}->{$hash});
  } else {
    return (undef, undef);
  }
} # get_entry

sub set_entry ($$$) {
  my ($hash, $is_pattern, $value) = @_;
  
  my $file_name = hash_to_file_name ($hash);
  unless ($Entry->{$file_name}) {
    $Entry->{$file_name} = read_data_file ($file_name);    
  }

  unless ($value) {
    delete $Entry->{$file_name}->{exact}->{$hash};
    delete $Entry->{$file_name}->{pattern}->{$hash};
  } elsif ($is_pattern) {
    delete $Entry->{$file_name}->{exact}->{$hash};
    $Entry->{$file_name}->{pattern}->{$hash} = $value;
  } else {
    $Entry->{$file_name}->{exact}->{$hash} = $value;
    delete $Entry->{$file_name}->{pattern}->{$hash};
  }
  $Entry->{$file_name}->{modified} = 1;
  $ModifiedHash->{$hash} = 1;
} # set_entry

use Fcntl ':flock';
my $Lock;

sub lock_entry ($) {
  if ($Lock) {
    die "$0: lock_entry: Another entry is locked";
  }

  my $hash = shift;
  my $file_name = hash_to_file_name ($hash) . $lock_suffix;
  open $Lock, '>', $file_name or die "$0: $file_name: $!";
  flock $Lock, LOCK_EX;
} # lock_entry

sub commit_entries ($) {
  for my $file_name (keys %{$Entry}) {
    if ($Entry->{$file_name}->{modified}) {
      delete $Entry->{$file_name}->{modified};
      write_data_file ($file_name => $Entry->{$file_name});
    }
  }

  open my $file, '>>', $patch_file_name or die "$0: $patch_file_name: $!";
  for (keys %$ModifiedHash) {
    print $file "$_\n";
  }
  close $file;

  my $msg = shift // $0;
  system_ ('cvs', 'commit', -m => $msg, $data2_dir_name) if $UseCVS;
} # commit_entries

sub get_all_entries () {
  opendir my $dir, $data2_dir_name or die "$0: $data2_dir_name: $!";
  for (readdir $dir) {
    next unless /\Q$data2_suffix\E$/;
    my $file_name = $data2_dir_name . $_;
    next if $Entry->{$file_name};

    $Entry->{$file_name} = read_data_file ($file_name);
  }

  return $Entry;
} # get_all_entries

sub for_each_entry_set ($;$) {
  my $code = shift;
  my $on_the_fly = shift;
  
  opendir my $dir, $data2_dir_name or die "$0: $data2_dir_name: $!";
  for (readdir $dir) {
    next unless /\Q$data2_suffix\E$/;
    my $file_name = $data2_dir_name . $_;
    next if $file_name eq $fallback_file_name;

    if ($Entry->{$file_name}) {
      $code->($file_name, $Entry->{$file_name});
    } elsif ($on_the_fly) {
      $code->($file_name, read_data_file ($file_name));
    } else {
      $Entry->{$file_name} = read_data_file ($file_name);
      $code->($file_name, $Entry->{$file_name});
    }
  }
} # for_each_entry_set

my $FallbackEntry;
sub get_fallback_entry ($) {
  my $hash = shift;
  unless (defined $FallbackEntry) {
    $FallbackEntry = read_data_file ($fallback_file_name);
  }
  return $FallbackEntry->{$hash} // {};
} # get_fallback_entry

sub get_entry_or_fallback_entry ($) {
  my $hash = shift;

  my ($is_pattern, $entry) = get_entry ($hash);
  unless (defined $entry->{en}) {
    $entry = get_fallback_entry ($hash);
  }
  $entry->{tags} ||= [];
  $entry->{isPattern} = 1 if $is_pattern;

  return $entry;
} # get_entry_or_fallback_entry

sub set_fallback_entry ($$) {
  my ($hash, $value) = @_;
  unless (defined $FallbackEntry) {
    $FallbackEntry = read_data_file ($fallback_file_name);
  }
  $FallbackEntry->{$hash} = $value;
} # set_fallback_entry

sub get_fallback_entries () {
  unless (defined $FallbackEntry) {
    $FallbackEntry = read_data_file ($fallback_file_name);
  }
  
  return $FallbackEntry;
} # get_fallback_entries

sub save_fallback_entries () {
  write_data_file ($fallback_file_name => $FallbackEntry)
      if defined $FallbackEntry;
} # save_fallback_entries

sub get_modified_hashes () {
  open my $file, '<', $patch_file_name or die "$0: $patch_file_name: $!";
  return map {tr/\x0D\x0A//d; $_} <$file>;
} # get_modified_hashes

sub normalize_width ($) {
  my $s = shift;
  $s =~ tr{\x{3000}\x{FF01}-\x{FF5E}\x{FF61}-\x{FF9F}\x{FFE0}-\x{FFE6}}
          { !-~。「」、・ヲァィゥェォャュョッーアイウエオカキクケコサシスセソタチツテトナニヌネノハヒフヘホマミムメモヤユヨラリルレロワン\x{3099}\x{309A}\xA2\xA3\xAC\xAF\xA6\xA5\x{20A9}};
  return $s;
} # normalize_width

sub htescape ($) {
  my $s = shift;
  $s =~ s/&/&amp;/g;
  $s =~ s/</&lt;/g;
  $s =~ s/"/&quot;/g;
  return $s;
} # htescape

sub system_ (@) {
  (system join (' ', map {quotemeta $_} @_) . " > /dev/null") == 0
      or die "$0: $?";
} # system_

1;

## Author: Wakaba <w@suika.fam.cx>.
## License: Copyright 2008 Wakaba.  You are granted a license to use,
##     reproduce and create derivative works of this script.
## $Date: 2008/11/05 01:29:08 $