--- trunk/lib/WebPAC/Input.pm	2005/07/16 20:35:30	10
+++ trunk/lib/WebPAC/Input.pm	2006/10/25 15:56:44	760
@@ -3,39 +3,56 @@
 use warnings;
 use strict;
 
+use blib;
+
+use WebPAC::Common;
+use base qw/WebPAC::Common/;
+use Data::Dumper;
+use Encode qw/from_to/;
+
 =head1 NAME
 
-WebPAC::Input - core module for input file format
+WebPAC::Input - read different file formats into WebPAC
 
 =head1 VERSION
 
-Version 0.01
+Version 0.13
 
 =cut
 
-our $VERSION = '0.01';
+our $VERSION = '0.13';
 
 =head1 SYNOPSIS
 
-This module will load particular loader module and execute it's functions.
+This module implements input as database which have fixed and known
+I<size> while indexing and single unique numeric identifier for database
+position ranging from 1 to I<size>.
+
+Simply, something that is indexed by unmber from 1 .. I<size>.
+
+Examples of such databases are CDS/ISIS files, MARC files, lines in
+text file, and so on.
+
+Specific file formats are implemented using low-level interface modules,
+located in C<WebPAC::Input::*> namespace which export C<open_db>,
+C<fetch_rec> and optional C<init> functions.
 
 Perhaps a little code snippet.
 
-    use WebPAC::Input;
+	use WebPAC::Input;
+
+	my $db = WebPAC::Input->new(
+		module => 'WebPAC::Input::ISIS',
+		low_mem => 1,
+	);
+
+	$db->open( path => '/path/to/database' );
+	print "database size: ",$db->size,"\n";
+	while (my $rec = $db->fetch) {
+		# do something with $rec
+	}
 
-    my $db = WebPAC::Input->new(
-    	format => 'NULL',
-	config => $config,
-	lookup => $lookup_obj,
-	low_mem => 1,
-    );
 
-    $db->open('/path/to/database');
-    print "database size: ",$db->size,"\n";
-    while (my $row = $db->fetch) {
-	...
-    }
-    $db->close;
 
 =head1 FUNCTIONS
 
@@ -44,28 +61,210 @@
 Create new input database object.
 
   my $db = new WebPAC::Input(
-  	format => 'NULL'
-	code_page => 'ISO-8859-2',
+	module => 'WebPAC::Input::MARC',
+	encoding => 'ISO-8859-2',
 	low_mem => 1,
+	recode => 'char pairs',
+	no_progress_bar => 1,
   );
 
-Optional parametar C<code_page> specify application code page (which will be
+C<module> is low-level file format module. See L<WebPAC::Input::ISIS> and
+L<WebPAC::Input::MARC>.
+
+Optional parametar C<encoding> specify application code page (which will be
 used internally). This should probably be your terminal encoding, and by
 default, it C<ISO-8859-2>.
 
 Default is not to use C<low_mem> options (see L<MEMORY USAGE> below).
 
+C<recode> is optional string constisting of character or words pairs that
+should be replaced in input stream.
+
+C<no_progress_bar> disables progress bar output on C<STDOUT>
+
+This function will also call low-level C<init> if it exists with same
+parametars.
+
 =cut
 
 sub new {
-        my $class = shift;
-        my $self = {@_};
+	my $class = shift;
+	my $self = {@_};
 	bless($self, $class);
 
-	$self->{'code_page'} ||= 'ISO-8859-2';
-
 	my $log = $self->_get_logger;
 
+	$log->logconfess("code_page argument is not suppored any more. change it to encoding") if ($self->{lookup});
+	$log->logconfess("lookup argument is not suppored any more. rewrite call to lookup_ref") if ($self->{lookup});
+
+	$log->logconfess("specify low-level file format module") unless ($self->{module});
+	my $module_path = $self->{module};
+	$module_path =~ s#::#/#g;
+	$module_path .= '.pm';
+	$log->debug("require low-level module $self->{module} from $module_path");
+
+	require $module_path;
+
+	# check if required subclasses are implemented
+	foreach my $subclass (qw/open_db fetch_rec init dump_rec/) {
+		# FIXME
+	}
+
+	$self->{'encoding'} ||= 'ISO-8859-2';
+
+	$self ? return $self : return undef;
+}
+
+=head2 open
+
+This function will read whole database in memory and produce lookups.
+
+ $input->open(
+ 	path => '/path/to/database/file',
+	code_page => 'cp852',
+	limit => 500,
+	offset => 6000,
+	stats => 1,
+	lookup_coderef => sub {
+		my $rec = shift;
+		# store lookups
+	},
+	modify_records => {
+		900 => { '^a' => { ' : ' => '^b' } },
+		901 => { '*' => { '^b' => ' ; ' } },
+	},
+	modify_file => 'conf/modify/mapping.map',
+ );
+
+By default, C<code_page> is assumed to be C<cp852>.
+
+C<offset> is optional parametar to position at some offset before reading from database.
+
+C<limit> is optional parametar to read just C<limit> records from database
+
+C<stats> create optional report about usage of fields and subfields
+
+C<lookup_coderef> is closure to called to save data into lookups
+
+C<modify_records> specify mapping from subfields to delimiters or from
+delimiters to subfields, as well as oprations on fields (if subfield is
+defined as C<*>.
+
+C<modify_file> is alternative for C<modify_records> above which preserves order and offers
+(hopefully) simplier sintax than YAML or perl (see L</modify_file_regex>). This option
+overrides C<modify_records> if both exists for same input.
+
+Returns size of database, regardless of C<offset> and C<limit>
+parametars, see also C<size>.
+
+=cut
+
+sub open {
+	my $self = shift;
+	my $arg = {@_};
+
+	my $log = $self->_get_logger();
+
+	$log->logconfess("lookup argument is not suppored any more. rewrite call to lookup_coderef") if ($arg->{lookup});
+	$log->logconfess("lookup_coderef must be CODE, not ",ref($arg->{lookup_coderef}))
+		if ($arg->{lookup_coderef} && ref($arg->{lookup_coderef}) ne 'CODE');
+
+	$log->debug( $arg->{lookup_coderef} ? '' : 'not ', "using lookup_coderef");
+
+	$log->logcroak("need path") if (! $arg->{'path'});
+	my $code_page = $arg->{'code_page'} || 'cp852';
+
+	# store data in object
+	$self->{'input_code_page'} = $code_page;
+	foreach my $v (qw/path offset limit/) {
+		$self->{$v} = $arg->{$v} if ($arg->{$v});
+	}
+
+	my $filter_ref;
+	my $recode_regex;
+	my $recode_map;
+
+	if ($self->{recode}) {
+		my @r = split(/\s/, $self->{recode});
+		if ($#r % 2 != 1) {
+			$log->logwarn("recode needs even number of elements (some number of valid pairs)");
+		} else {
+			while (@r) {
+				my $from = shift @r;
+				my $to = shift @r;
+				$recode_map->{$from} = $to;
+			}
+
+			$recode_regex = join '|' => keys %{ $recode_map };
+
+			$log->debug("using recode regex: $recode_regex");
+		}
+
+	}
+
+	my $rec_regex;
+	if (my $p = $arg->{modify_file}) {
+		$log->debug("using modify_file $p");
+		$rec_regex = $self->modify_file_regexps( $p );
+	} elsif (my $h = $arg->{modify_records}) {
+		$log->debug("using modify_records ", Dumper( $h ));
+		$rec_regex = $self->modify_record_regexps(%{ $h });
+	}
+	$log->debug("rec_regex: ", Dumper($rec_regex)) if ($rec_regex);
+
+	my $class = $self->{module} || $log->logconfess("can't get low-level module name!");
+
+	my $ll_db = $class->new(
+		path => $arg->{path},
+#		filter => sub {
+#			my ($l,$f_nr) = @_;
+#			return unless defined($l);
+#			from_to($l, $code_page, $self->{'encoding'});
+#			$l =~ s/($recode_regex)/$recode_map->{$1}/g if ($recode_regex && $recode_map);
+#			return $l;
+#		},
+		%{ $arg },
+	);
+
+	unless (defined($ll_db)) {
+		$log->logwarn("can't open database $arg->{path}, skipping...");
+		return;
+	}
+
+	my $size = $ll_db->size;
+
+	unless ($size) {
+		$log->logwarn("no records in database $arg->{path}, skipping...");
+		return;
+	}
+
+	my $from_rec = 1;
+	my $to_rec = $size;
+
+	if (my $s = $self->{offset}) {
+		$log->debug("skipping to MFN $s");
+		$from_rec = $s;
+	} else {
+		$self->{offset} = $from_rec;
+	}
+
+	if ($self->{limit}) {
+		$log->debug("limiting to ",$self->{limit}," records");
+		$to_rec = $from_rec + $self->{limit} - 1;
+		$to_rec = $size if ($to_rec > $size);
+	}
+
+	# store size for later
+	$self->{size} = ($to_rec - $from_rec) ? ($to_rec - $from_rec + 1) : 0;
+
+	$log->info("processing $self->{size}/$size records [$from_rec-$to_rec] convert $code_page -> $self->{encoding}", $self->{stats} ? ' [stats]' : '');
+
+	# turn on low_mem for databases with more than 100000 records!
+	if (! $self->{low_mem} && $size > 100000) {
+		$log->warn("Using on-disk storage instead of memory for input data. This will affect performance.");
+		$self->{low_mem}++;
+	}
+
 	# running with low_mem flag? well, use DBM::Deep then.
 	if ($self->{'low_mem'}) {
 		$log->info("running with low_mem which impacts performance (<32 Mb memory usage)");
@@ -92,7 +291,384 @@
 		$self->{'db'} = $db;
 	}
 
-	$self ? return $self : return undef;
+	# read database
+	for (my $pos = $from_rec; $pos <= $to_rec; $pos++) {
+
+		$log->debug("position: $pos\n");
+
+		my $rec = $ll_db->fetch_rec($pos, sub {
+				my ($l,$f_nr) = @_;
+#				return unless defined($l);
+#				return $l unless ($rec_regex && $f_nr);
+
+				$log->debug("-=> $f_nr ## $l");
+
+				# codepage conversion and recode_regex
+				from_to($l, $code_page, $self->{'encoding'});
+				$l =~ s/($recode_regex)/$recode_map->{$1}/g if ($recode_regex && $recode_map);
+
+				# apply regexps
+				if ($rec_regex && defined($rec_regex->{$f_nr})) {
+					$log->logconfess("regexps->{$f_nr} must be ARRAY") if (ref($rec_regex->{$f_nr}) ne 'ARRAY');
+					my $c = 0;
+					foreach my $r (@{ $rec_regex->{$f_nr} }) {
+						my $old_l = $l;
+						eval '$l =~ ' . $r;
+						if ($old_l ne $l) {
+							$log->debug("REGEX on $f_nr eval \$l =~ $r\n## old l: [$old_l]\n## new l: [$l]");
+						}
+						$log->error("error applying regex: $r") if ($@);
+					}
+				}
+
+				$log->debug("<=- $f_nr ## $l");
+				return $l;
+		});
+
+		$log->debug(sub { Dumper($rec) });
+
+		if (! $rec) {
+			$log->warn("record $pos empty? skipping...");
+			next;
+		}
+
+		# store
+		if ($self->{low_mem}) {
+			$self->{db}->put($pos, $rec);
+		} else {
+			$self->{data}->{$pos} = $rec;
+		}
+
+		# create lookup
+		$arg->{'lookup_coderef'}->( $rec ) if ($rec && $arg->{'lookup_coderef'});
+
+		# update counters for statistics
+		if ($self->{stats}) {
+
+			# fetch clean record with regexpes applied for statistics
+			my $rec = $ll_db->fetch_rec($pos);
+
+			foreach my $fld (keys %{ $rec }) {
+				$self->{_stats}->{fld}->{ $fld }++;
+
+				$log->logdie("invalid record fild $fld, not ARRAY")
+					unless (ref($rec->{ $fld }) eq 'ARRAY');
+	
+				foreach my $row (@{ $rec->{$fld} }) {
+
+					if (ref($row) eq 'HASH') {
+
+						foreach my $sf (keys %{ $row }) {
+							next if ($sf eq 'subfields');
+							$self->{_stats}->{sf}->{ $fld }->{ $sf }->{count}++;
+							$self->{_stats}->{sf}->{ $fld }->{ $sf }->{repeatable}++
+									if (ref($row->{$sf}) eq 'ARRAY');
+						}
+
+					} else {
+						$self->{_stats}->{repeatable}->{ $fld }++;
+					}
+				}
+			}
+		}
+
+		$self->progress_bar($pos,$to_rec) unless ($self->{no_progress_bar});
+
+	}
+
+	$self->{pos} = -1;
+	$self->{last_pcnt} = 0;
+
+	# store max mfn and return it.
+	$self->{max_pos} = $to_rec;
+	$log->debug("max_pos: $to_rec");
+
+	# save for dump
+	$self->{ll_db} = $ll_db;
+
+	return $size;
+}
+
+=head2 fetch
+
+Fetch next record from database. It will also displays progress bar.
+
+ my $rec = $isis->fetch;
+
+Record from this function should probably go to C<data_structure> for
+normalisation.
+
+=cut
+
+sub fetch {
+	my $self = shift;
+
+	my $log = $self->_get_logger();
+
+	$log->logconfess("it seems that you didn't load database!") unless ($self->{pos});
+
+	if ($self->{pos} == -1) {
+		$self->{pos} = $self->{offset};
+	} else {
+		$self->{pos}++;
+	}
+
+	my $mfn = $self->{pos};
+
+	if ($mfn > $self->{max_pos}) {
+		$self->{pos} = $self->{max_pos};
+		$log->debug("at EOF");
+		return;
+	}
+
+	$self->progress_bar($mfn,$self->{max_pos}) unless ($self->{no_progress_bar});
+
+	my $rec;
+
+	if ($self->{low_mem}) {
+		$rec = $self->{db}->get($mfn);
+	} else {
+		$rec = $self->{data}->{$mfn};
+	}
+
+	$rec ||= 0E0;
+}
+
+=head2 pos
+
+Returns current record number (MFN).
+
+ print $isis->pos;
+
+First record in database has position 1.
+
+=cut
+
+sub pos {
+	my $self = shift;
+	return $self->{pos};
+}
+
+
+=head2 size
+
+Returns number of records in database
+
+ print $isis->size;
+
+Result from this function can be used to loop through all records
+
+ foreach my $mfn ( 1 ... $isis->size ) { ... }
+
+because it takes into account C<offset> and C<limit>.
+
+=cut
+
+sub size {
+	my $self = shift;
+	return $self->{size};
+}
+
+=head2 seek
+
+Seek to specified MFN in file.
+
+ $isis->seek(42);
+
+First record in database has position 1.
+
+=cut
+
+sub seek {
+	my $self = shift;
+	my $pos = shift || return;
+
+	my $log = $self->_get_logger();
+
+	if ($pos < 1) {
+		$log->warn("seek before first record");
+		$pos = 1;
+	} elsif ($pos > $self->{max_pos}) {
+		$log->warn("seek beyond last record");
+		$pos = $self->{max_pos};
+	}
+
+	return $self->{pos} = (($pos - 1) || -1);
+}
+
+=head2 stats
+
+Dump statistics about field and subfield usage
+
+  print $input->stats;
+
+=cut
+
+sub stats {
+	my $self = shift;
+
+	my $log = $self->_get_logger();
+
+	my $s = $self->{_stats};
+	if (! $s) {
+		$log->warn("called stats, but there is no statistics collected");
+		return;
+	}
+
+	my $max_fld = 0;
+
+	my $out = join("\n",
+		map {
+			my $f = $_ || die "no field";
+			my $v = $s->{fld}->{$f} || die "no s->{fld}->{$f}";
+			$max_fld = $v if ($v > $max_fld);
+
+			my $o = sprintf("%4s %d ~", $f, $v);
+
+			if (defined($s->{sf}->{$f})) {
+				map {
+					$o .= sprintf(" %s:%d%s", $_, 
+						$s->{sf}->{$f}->{$_}->{count},
+						$s->{sf}->{$f}->{$_}->{repeatable} ? '*' : '',
+					);
+				} sort keys %{ $s->{sf}->{$f} };
+			}
+
+			if (my $v_r = $s->{repeatable}->{$f}) {
+				$o .= " ($v_r)" if ($v_r != $v);
+			}
+
+			$o;
+		} sort { $a cmp $b } keys %{ $s->{fld} }
+	);
+
+	$log->debug( sub { Dumper($s) } );
+
+	return $out;
+}
+
+=head2 dump
+
+Display humanly readable dump of record
+
+=cut
+
+sub dump {
+	my $self = shift;
+
+	return $self->{ll_db}->dump_rec( $self->{pos} );
+
+}
+
+=head2 modify_record_regexps
+
+Generate hash with regexpes to be applied using l<filter>.
+
+  my $regexpes = $input->modify_record_regexps(
+		900 => { '^a' => { ' : ' => '^b' } },
+		901 => { '*' => { '^b' => ' ; ' } },
+  );
+
+=cut
+
+sub _get_regex {
+	my ($sf,$from,$to) = @_;
+	if ($sf =~ /^\^/) {
+		return
+			's/\Q'. $sf .'\E([^\^]*?)\Q'. $from .'\E([^\^]*?)/'. $sf .'$1'. $to .'$2/';
+	} else {
+		return
+			's/\Q'. $from .'\E/'. $to .'/g';
+	}
+}
+
+sub modify_record_regexps {
+	my $self = shift;
+	my $modify_record = {@_};
+
+	my $regexpes;
+
+	my $log = $self->_get_logger();
+
+	foreach my $f (keys %$modify_record) {
+		$log->debug("field: $f");
+
+		foreach my $sf (keys %{ $modify_record->{$f} }) {
+			$log->debug("subfield: $sf");
+
+			foreach my $from (keys %{ $modify_record->{$f}->{$sf} }) {
+				my $to = $modify_record->{$f}->{$sf}->{$from};
+				#die "no field?" unless defined($to);
+				$log->debug("transform: |$from| -> |$to|");
+
+				my $regex = _get_regex($sf,$from,$to);
+				push @{ $regexpes->{$f} }, $regex;
+				$log->debug("regex: $regex");
+			}
+		}
+	}
+
+	return $regexpes;
+}
+
+=head2 modify_file_regexps
+
+Generate hash with regexpes to be applied using l<filter> from
+pseudo hash/yaml format for regex mappings.
+
+It should be obvious:
+
+	200
+	  '^a'
+	    ' : ' => '^e'
+	    ' = ' => '^d'
+
+In field I<200> find C<'^a'> and then C<' : '>, and replace it with C<'^e'>.
+In field I<200> find C<'^a'> and then C<' = '>, and replace it with C<'^d'>.
+
+  my $regexpes = $input->modify_file_regexps( 'conf/modify/common.pl' );
+
+On undef path it will just return.
+
+=cut
+
+sub modify_file_regexps {
+	my $self = shift;
+
+	my $modify_path = shift || return;
+
+	my $log = $self->_get_logger();
+
+	my $regexpes;
+
+	CORE::open(my $fh, $modify_path) || $log->logdie("can't open modify file $modify_path: $!");
+
+	my ($f,$sf);
+
+	while(<$fh>) {
+		chomp;
+		next if (/^#/ || /^\s*$/);
+
+		if (/^\s*(\d+)\s*$/) {
+			$f = $1;
+			$log->debug("field: $f");
+			next;
+		} elsif (/^\s*'([^']*)'\s*$/) {
+			$sf = $1;
+			$log->die("can't define subfiled before field in: $_") unless ($f);
+			$log->debug("subfield: $sf");
+		} elsif (/^\s*'([^']*)'\s*=>\s*'([^']*)'\s*$/) {
+			my ($from,$to) = ($1, $2);
+
+			$log->debug("transform: |$from| -> |$to|");
+
+			my $regex = _get_regex($sf,$from,$to);
+			push @{ $regexpes->{$f} }, $regex;
+			$log->debug("regex: $regex");
+		}
+	}
+
+	return $regexpes;
 }
 
 =head1 MEMORY USAGE
@@ -132,7 +708,7 @@
 
 =head1 COPYRIGHT & LICENSE
 
-Copyright 2005 Dobrica Pavlinusic, All Rights Reserved.
+Copyright 2005-2006 Dobrica Pavlinusic, All Rights Reserved.
 
 This program is free software; you can redistribute it and/or modify it
 under the same terms as Perl itself.