package Ernad::Files;

use strict;
use warnings;

use Carp qw(confess);
use Cwd 'abs_path';
use Data::Dumper;
use File::Basename;
use File::Copy;
use File::Compare;
use File::Path;
use File::Temp qw/ tempfile tempdir /;
use File::Slurper;
use File::Slurp;
use IO::Compress::Gzip qw(gzip $GzipError);

use Ernad::Constant;
use Krichel::File;

sub exist {
  my $glob=shift // confess "I need a glob here.";
  my @globs = glob($glob);
  if( scalar( @globs ) > 0 ) {
    return 1;
  }
  return 0;
}

sub get_abs_path {
  my $file=shift or return '';
  my $abs_path;
  #if( -f $file && -l $file ) {
  $abs_path=abs_path($file);
  #}
  #print "abs_path is $abs_path\n";
  return $abs_path;
}

sub save_xml_with_temp {
  my $dest_file=shift;
  my $doc=shift;
  my ($fh, $temp_file) = tempfile();
  #print $doc->toString;
  $doc->toFile($temp_file,2);
  if(not -f $dest_file or
     compare($dest_file,$temp_file)) {
    copy($temp_file,$dest_file);
    return 1;
  }
  unlink $temp_file;
  return 0;
}

## new function, saves both text and xml
sub save_if_diff {
  my $file=shift;
  my $in=shift;
  my $ref_in=ref($in);
  if($ref_in eq 'XML::LibXML::Document') {
    my $has_saved=&save_xml_with_temp($file,$in);
    return $has_saved;
  }
  if(not $ref_in) {
    my $has_saved=&save_text_with_temp($file,$in);
    return $has_saved;
  }
  confess "I can't deal with your input of time $ref_in.";
}

sub save_text_with_temp {
  my $dest_file=shift;
  my $txt=shift;
  my ($fh, $temp_file) = tempfile();
  &File::Slurper::write_text($temp_file,$txt);
  my $status=0;
  if(not -f $dest_file or
     compare($dest_file,$temp_file)) {
    copy($temp_file,$dest_file);
    $status=1;
  }
  unlink $temp_file;
  return $status;
}

sub write_doc {
  my $arg_1=shift // confess "I need two arguments here";
  my $arg_2=shift // confess "I need two arguments here";
  my $ref_1=ref $arg_1;
  my $ref_2=ref $arg_2;
  my $file;
  my $doc;
  if($ref_1 eq 'XML::LibXML::Document' and not $ref_2) {
    $file=$arg_2;
    $doc=$arg_1;
  }
  elsif($ref_2 eq 'XML::LibXML::Document' and not $ref_2) {
    $file=$arg_1;
    $doc=$arg_2;
  }
  if(not -f $file) {
    if(substr($file,-3) eq '.gz') {
      $file=substr($file,0,length($file)-3);
      $doc->toFile($file);
      system("/bin/gzip $file");
      return "$file.gz";
    }
    $doc->toFile($file);
    return $file;
  }
  my $status=0;
  my ($fh, $temp_file) = tempfile();
  $doc->toFile($temp_file);
  if(substr($file,-3) eq '.gz') {
    system("/bin/gzip $temp_file");
    $temp_file.='.gz';
  }
  if(compare($file,$temp_file)) {
    copy($temp_file,$file);
    $status=1;
  }
  unlink $temp_file;
  return $status;
}


sub write_string {
  my $file=shift // confess "I need a file here";
  &Krichel::File::prepare($file);
  my $txt=shift // confess "I need a string here.";
  if(ref($txt)) {
    confess "I need as string, not an object.";
  }
  if(not $txt) {
    confess "I don't write an empty string to a file.";
  }
  if($file=~m|\.gz$|) {
    my $fh;
    $fh = IO::Compress::Gzip->new($file)
      or confess "I not write to $file: $GzipError";
    $fh->print($txt);
    $fh->close();
    return 1;
  }
  &File::Slurp::write_file($file,$txt);
  return 1;
}



sub read_string {
  my $file=shift;
  my $txt;
  if($file=~m|\.gz$|) {
    my $input = new IO::File "< $file"
      or confess "I can not open '$file': $!" ;
    gzip $input => \$txt or confess
      "I could not read the compressid file $file $GzipError\n";
    return $txt;
  }
  $txt=&File::Slurp::read_file($file);
  return $txt;
}

## seems wrong because it does not account for gz
sub save_xml_with_temp_and_time {
  my $dest_file=shift;
  my $doc=shift;
  my ($fh, $temp_file) = tempfile();
  $doc->toFile($temp_file,2);
  my $dir=dirname($dest_file);
  if(not -d $dir) {
    mkpath $dir;
    copy($temp_file,$dest_file);
    unlink $temp_file;
    return 1;
  }
  my $bana=basename($dest_file);
  $bana=~m|([^.]+)\.(.*)|;
  my $main=$1;
  my $ext=$2;
  ## old way to do time
  if($main=~m|(.*_)\d{10}$|) {
    my $b4digit=$1;
    my $search="$dir/$b4digit*.$ext";
    my @allready_there_files=glob($search);
    if(scalar @allready_there_files) {
      foreach my $candidate (@allready_there_files) {
        if(compare($candidate,$temp_file)==0) {
          ## a copy of this is already there
          #print "found an eearlier copy $candidate\n";
          return 0;
        }
      }
    }
  }
  ## new way to do time
  if($main=~m|(.*_)[0-9a-z]{6}$|) {
    my $b4digit=$1;
    my $search="$dir/$b4digit*.$ext";
    my @allready_there_files=glob($search);
    if(scalar @allready_there_files) {
      foreach my $candidate (@allready_there_files) {
        if(compare($candidate,$temp_file)==0) {
          ## a copy of this is already there
          #print "found an eearlier copy $candidate\n";
          return 0;
        }
      }
    }
  }
  copy($temp_file,$dest_file);
  unlink $temp_file;
  return 1;
}

## fixme prepare should be an alias and all references
## to prepare_for_file should be changed


#sub prepare {
#  my $file=shift // '';
#  if(not $file) {
#    confess "I need a file here.";
#  }
#  my $dir=dirname($file);
#  if(-d $dir) {
#    return;
#  }
#  #print "Trying to make $dir\n";
#  my $target=readlink($dir) // '';
#  #print "target is $target\n";
#  if($target) {
#    mkpath($target);
#    return;
#  }
#  #print "directory $dir is not a link\n";
#  #print `ls $dir`;
#  if(not -d $dir) {
#    unlink $dir;
#    mkpath($dir);
#  }
#}
#
# sub prepare_for_file {
#   my $file=shift // '';
#   if(not $file) {
#     confess "I need a file here.";
#   }
#   my $dir=dirname($file);
#   if(-d $dir) {
#     return;
#   }
#   #print "Trying to make $dir\n";
#   my $target=readlink($dir) // '';
#   #print "target is $target\n";
#   if($target) {
#     mkpath($target);
#     return;
#   }
#   #print "directory $dir is not a link\n";
#   #print `ls $dir`;
#   if(not -d $dir) {
#     unlink $dir;
#     mkpath($dir);
#   }
# }

sub xml_to_html {
  my $xml_file=shift;
  my $dir=shift // '';
  my $xml_bana=basename($xml_file);
  my $html_bana=substr($xml_bana,0,length($xml_bana)-4);
  my $html_fufi="$dir/$html_bana.html";
  return $html_fufi;
}

sub is_emacs_file {
  my $file=shift;
  ## emacs backups
  if($file=~m|~|) {
    return 1;
  }
  ## emacs autosaves
  my $bana=basename($file);
  if($bana=~m|^#| and $bana=~m|#$|) {
    return 1;
  }
}

sub check_link {
  my $in_link=shift;
  my $verbose=0;
  if(not -l $in_link) {
    return;
  }
  my $dir=&dirname($in_link);
  if($verbose) {
    print "in_link is $in_link\n";
  }
  my $target=$dir.'/'.readlink $in_link;
  if($verbose) {
    print "target is $target\n";
  }
  if(not -f $target) {
    warn "broken link $in_link";
    system("rm $in_link");
  }
}

sub remove_dangling_opt_link_to_file {
  my $in=shift;
  my $verbose=0;
  if(-f $in) {
    return;
  }
  if(-l $in) {
    return;
  }
  my $no_opt_out_file=Ernad::Files::remove_opt($in);
  if(-l $no_opt_out_file) {
    &Ernad::Files::check_link($no_opt_out_file);
    if($verbose) {
      print "I delete the link $no_opt_out_file\n";
    }
    system("rm $no_opt_out_file");
  }
}

sub check_links_in_dir {
  my $dir=shift or die;
  my $verbose=0;
  if(not -d $dir) {
    die "no such directory '$dir'";
  }
  my $file;
  my $dh;
  opendir(DH, $dir);
  while ($file = readdir DH ) {
    if(not -l $file) {
      next;
    }
    if($verbose) {
      print "$file\n";
    }
    my $link="$dir/$file";
    &check_link($link);
  }
}


sub remove_opt {
  my $in=shift;
  my $opt=$Ernad::Constant::c->{'opt_dir'};
  my $no_opt=$in;
  $no_opt=~s|(.*)/$opt/(.*)|$1/$2|;
  if(not $in=~m|/$opt/|) {
    return '';
  }
  return $no_opt;
}

sub make_opt_link {
  my $in=shift;
  my $no_opt=$in;
  my $verbose=0;
  my $opt=$Ernad::Constant::c->{'opt_dir'};
  if(not $in=~m|/$opt/|) {
    return;
  }
  $no_opt=~s|(.*)/$opt/(.*)|$1/$2|;
  my $before_opt=$1;
  my $after_opt=$2;
  if(-f $no_opt and not -l $no_opt) {
    if($verbose) {
      print "an extra non-opt file $no_opt is there\n";
    }
    return;
  }
  if(-f $no_opt) {
    if($verbose) {
      print "file $no_opt is there\n";
    }
    return;
  }
  if(-r $no_opt) {
    if($verbose) {
      print "link $no_opt is there\n";
    }
    return;
  }
  my $sys="cd $before_opt; ln -s $opt/$after_opt $after_opt";
  if($verbose) {
    print "running '$sys'\n";
  }
  system($sys);
}


sub check_text_link {
  my $in_file=shift;
  my $out_dir=shift;
  my $verbose=0;
  my $in_dir=dirname($in_file);
  my $fina=basename($in_file);
  my $out_file="$out_dir/$fina";
  if(-l "$in_file.txt" and not -l "$out_file.txt") {
    unlink "$out_file.txt";
    my $out_fina=basename($out_file);
    my $s="cd $out_dir; ln -s $fina $fina.txt";
    if($verbose) {
      print "linking $s\n";
    }
    system($s);
  }
}


sub does_file_need_renewal {
  my $in_file=shift;
  my @others=@_;
  my $verbose=0;
  my $now=time;
  if(not -f $in_file) {
    if($verbose) {
      print "file $in_file is not there, it needs renewing.\n";
    }
    return $now;
  }
  if($verbose) {
    print "file $in_file is there ... ";
  }
  if(-z $in_file) {
    if($verbose) {
      print "file $in_file is empty, it needs renewing.\n";
    }
    return time;
  }
  ## -M  Script start time minus file modification time, in days.
  my $target_time=-M $in_file;
  if($verbose) {
    print "target_time is $target_time\n";
  }
  if($verbose) {
    print Dumper @others;
  }
  my $min_ago=time;
  foreach my $file (@others) {
    if($verbose) {
      print "considering $file as renewal target\n";
    }
    if(not $file) {
      confess "I don't have the file $file";
    }
    if(-d $file) {
      ## directory case, not treated recursively
      my $dirname=$file;
      opendir( my $dir, $dirname ) or die "Error: can't open dir $dirname";
      my $file;
      while ($file = readdir $dir ) {
        ## skipping "." and ".."
        if ( ($file eq "." ) or ( $file eq ".." )) {
          next;
        }
        $file="$dirname/$file";
        if(not -M $file) {
          die "can not find time on file $file";
        }
        my $ago=-M $file;
        if($ago < $min_ago) {
          $min_ago=$ago;
        }
      }
      ## finished with this
      next;
    }
    if(not -f $file) {
      confess "I can not find the file '$file'";
    }
    #if(not -M $file) {
    #  confess "I can not find the time on file '$file'";
    #}
    my $ago=-M $file;
    if($verbose) {
      print "time on file $file is $ago\n";
    }
    if($ago < $min_ago) {
      $min_ago=$ago;
    }
  }
  if($min_ago < $target_time) {
    if($verbose) {
      print " but $in_file is newer, renewal required\n";
    }
    my $time=time()+$min_ago;
    return $time;
  }
  if($verbose) {
    print " no reed to renew $in_file\n";
  }
  return 0;
}


sub check_opt_links {
  my $web_opt_dir=shift;
  my $verbose=0;
  foreach my $file (`find $web_opt_dir`) {
    chomp $file;
    if(not $file) {
      next;
    }
    my $no_opt=&Ernad::Files::remove_opt($file);
    if(not $no_opt) {
      if($verbose) {
        print "found no no_opt file\n";
      }
      next;
    }
    if(-l $no_opt) {
      if($verbose) {
        print "$no_opt link is there.\n";
      }
      next;
    }
    if(&Ernad::Files::get_abs_path($no_opt) eq $file) {
      if($verbose) {
        print "$no_opt is the same as $file\n";
      }
      next;
    }
    if(-d $no_opt) {
      next;
    }
    print "no_opt '$no_opt'\n";
    &make_opt_link($file,$no_opt);
  }
}

##
sub mtime {
  my $file=shift // confess "I need a file here.";
  if(not -f $file) {
    confess "I can't see the file $file";
  }
  my ($dev,$ino,$mode,$nlink,$uid,$gid,$rdev,$size,
      $atime,$mtime,$ctime,$blksize,$blocks)
    = stat($file);
  return $mtime;
}


###

sub count_amf_files_in_dir {
  my $dir=shift;
  opendir(DH, $dir) or
    confess "I can't open the directory $dir";
  my $ext=$Ernad::Constant::c->{'amf_ext'};
  my $count=0;
  my $file;
  my $debug=0;
  while ($file = readdir DH ) {
    if($debug) {
      print "I look at file $file, looking for $ext.\n";
    }
    if($file=~m|\Q$ext\E$|) {
      if($debug) {
        print "found file $file\n";
      }
      $count++;
    }
  }
  return $count;
}


1;