#!/usr/bin/perl -w

###########################################################################
#
# gti.pl
#
# A component of the Greenstone digital library software
# from the New Zealand Digital Library Project at the 
# University of Waikato, New Zealand.
#
# Copyright (C) 2005 New Zealand Digital Library Project
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
#
###########################################################################


BEGIN {
    die "GSDLHOME not set\n" unless defined $ENV{'GSDLHOME'};
    unshift (@INC, "$ENV{'GSDLHOME'}/perllib");
}


use iso639;
use strict;
use util;


my $anonymous_cvs_root = ":pserver:cvs_anon\@cvs.scms.waikato.ac.nz:2402/usr/local/global-cvs/gsdl-src";
my $gsdl_root_directory = "$ENV{'GSDLHOME'}";
my $gti_log_file = &util::filename_cat($gsdl_root_directory, "etc", "gti.log");
my $source_language_code = "en";  # This is non-negiotable

my $gti_translation_files =
    [ # Greenstone macrofiles
      { 'key' => "coredm",
	'file_type' => "macrofile",
	'source_file' => "macros/english.dm",
	'target_file' => "macros/{bn:bengali;fa:farsi;gd:gaelic;id:indo;lv:latvian;pt-br:port-br;pt-pt:port-pt;zh-tr:chinese-trad;iso_639_1_target_language_name}.dm" },
      { 'key' => "auxdm",
	'file_type' => "macrofile",
	'source_file' => "macros/english2.dm",
	'target_file' => "macros/{bn:bengali;fa:farsi;gd:gaelic;id:indo;lv:latvian;pt-br:port-br;pt-pt:port-pt;zh-tr:chinese-trad;iso_639_1_target_language_name}2.dm" },

      # GLI dictionary
      { 'key' => "glidict",
	'file_type' => "resource_bundle",
	'source_file' => "gli/classes/dictionary.properties",
	'target_file' => "gli/classes/dictionary_{target_language_code}.properties" },

      # GLI help
      { 'key' => "glihelp",
	'file_type' => "greenstone_xml",
	'source_file' => "gli/help/en/help.xml",
	'target_file' => "gli/help/{target_language_code}/help.xml" },

      # Greenstone Perl modules
      { 'key' => "perlmodules",
	'file_type' => "resource_bundle",
	'source_file' => "perllib/strings.properties",
	'target_file' => "perllib/strings_{target_language_code}.properties" },

      # Greenstone tutorial exercises
      # { 'key' => "tutorials",
	# 'file_type' => "greenstone_xml",
	# 'source_file' => "gsdl-tutorials/tutorial_en.xml",
	# 'target_file' => "gsdl-tutorials/tutorial_{target_language_code}.xml" },

      # Greenstone.org
      # { 'key' => "greenorg",
	# 'file_type' => "macrofile",
	# 'source_file' => "greenorg/macros/english.dm",
	# 'target_file' => "greenorg/macros/{iso_639_1_target_language_name}.dm" }
    ];


sub main
{
    # Get the command to process, and any arguments
    my $gti_command = shift(@_);
    my @gti_command_arguments = @_;

    # Open the GTI log file for appending, or write to STDERR if that fails
    if (!open(GTI_LOG, ">>$gti_log_file")) {
	open(GTI_LOG, ">&STDERR");
    }

    # Log the command that launched this script
    &log_message("Command: $0 @ARGV");

    # Check that a command was supplied
    if (!$gti_command) {
	&throw_fatal_error("Missing command.");
    }

    # Process the command
    if ($gti_command =~ /^get-first-n-chunks-requiring-work$/i) {
	print &get_first_n_chunks_requiring_work(@gti_command_arguments);
    }
    if ($gti_command =~ /^get-language-status$/i) {
	print &get_language_status(@gti_command_arguments);
    }
    if ($gti_command =~ /^search-chunks$/i) {
	print &search_chunks(@gti_command_arguments);
    }
    if ($gti_command =~ /^submit-translations$/i) {
	# This command cannot produce any output since it reads input
	&submit_translations(@gti_command_arguments);
    }

    # The command was not recognized
    # &throw_fatal_error("Unknown command \"$gti_command\".");
}


sub throw_fatal_error
{
    my $error_message = shift(@_);

    # Write an XML error response
    print "<?xml version=\"1.0\" encoding=\"UTF-8\" ?>\n";
    print "<GTIResponse>\n";
    print "  <GTIError time=\"" . time() . "\">" . $error_message . "</GTIError>\n";
    print "</GTIResponse>\n";

    # Log the error message, then die
    &log_message("Error: $error_message");
    die "\n";
}


sub log_message
{
    my $log_message = shift(@_);
    print GTI_LOG time() . " -- " . $log_message . "\n";
}


sub get_first_n_chunks_requiring_work
{
    # The code of the target language (ensure it is lowercase)
    my $target_language_code = lc(shift(@_));
    # The key of the file to translate (ensure it is lowercase)
    my $translation_file_key = lc(shift(@_));
    # The number of chunks to return (defaults to one if not specified)
    my $num_chunks_to_return = shift(@_) || "1";

    # Check that the necessary arguments were supplied
    if (!$target_language_code || !$translation_file_key) {
	&throw_fatal_error("Missing command argument.");
    }

    # Get (and check) the translation configuration
    my ($source_file, $target_file, $translation_file_type)
	= &get_translation_configuration($target_language_code, $translation_file_key);

    # Parse the source language and target language files
    my $source_file_path = &util::filename_cat($gsdl_root_directory, $source_file);
    my @source_file_lines = &read_file_lines($source_file_path);
    my %source_file_key_to_line_mapping = &build_key_to_line_mapping(\@source_file_lines, $translation_file_type);

    my $target_file_path = &util::filename_cat($gsdl_root_directory, $target_file);
    my @target_file_lines = &read_file_lines($target_file_path);
    my %target_file_key_to_line_mapping = &build_key_to_line_mapping(\@target_file_lines, $translation_file_type);

    # Filter out any automatically translated chunks
    foreach my $chunk_key (keys(%source_file_key_to_line_mapping)) {
	if (&is_chunk_automatically_translated($chunk_key, $translation_file_type)) {
	    delete $source_file_key_to_line_mapping{$chunk_key};
	    delete $target_file_key_to_line_mapping{$chunk_key};
	}
    }

    my %source_file_key_to_text_mapping = &build_key_to_text_mapping(\@source_file_lines, \%source_file_key_to_line_mapping, $translation_file_type);
    my %target_file_key_to_text_mapping = &build_key_to_text_mapping(\@target_file_lines, \%target_file_key_to_line_mapping, $translation_file_type);
    &log_message("Number of source chunks: " . scalar(keys(%source_file_key_to_text_mapping)));
    &log_message("Number of target chunks: " . scalar(keys(%target_file_key_to_text_mapping)));

    # Determine the target file chunks requiring translation
    my @target_file_keys_requiring_translation = &determine_chunks_requiring_translation(\%source_file_key_to_text_mapping, \%target_file_key_to_text_mapping);
    &log_message("Number of target chunks requiring translation: " . scalar(@target_file_keys_requiring_translation));

    # Determine the target file chunks requiring updating
    my %source_file_key_to_last_update_date_mapping = &build_key_to_last_update_date_mapping($source_file, \@source_file_lines, \%source_file_key_to_line_mapping, $translation_file_type);
    my %target_file_key_to_last_update_date_mapping = &build_key_to_last_update_date_mapping($target_file, \@target_file_lines, \%target_file_key_to_line_mapping, $translation_file_type);
    my @target_file_keys_requiring_updating = &determine_chunks_requiring_updating(\%source_file_key_to_last_update_date_mapping, \%target_file_key_to_last_update_date_mapping);
    &log_message("Number of target chunks requiring updating: " . scalar(@target_file_keys_requiring_updating));

    # Form an XML response to the command
    my $xml_response = "<?xml version=\"1.0\" encoding=\"UTF-8\" ?>\n";
    $xml_response .= "<GTIResponse>\n";
    $xml_response .= "  <TranslationFile"
	. " key=\"" . $translation_file_key . "\""
	. " target_file_path=\"" . $target_file . "\""
	. " num_chunks_translated=\"" . (scalar(keys(%source_file_key_to_text_mapping)) - scalar(@target_file_keys_requiring_translation)) . "\""
	. " num_chunks_requiring_translation=\"" . scalar(@target_file_keys_requiring_translation) . "\""
	. " num_chunks_requiring_updating=\"" . scalar(@target_file_keys_requiring_updating) . "\"\/>\n";

    # Do chunks requiring translation first
    if ($num_chunks_to_return > scalar(@target_file_keys_requiring_translation)) {
	$xml_response .= "  <ChunksRequiringTranslation size=\"" . scalar(@target_file_keys_requiring_translation) . "\">\n";
    }
    else {
	$xml_response .= "  <ChunksRequiringTranslation size=\"" . $num_chunks_to_return . "\">\n";
    }

    foreach my $chunk_key (@target_file_keys_requiring_translation) {
	last if ($num_chunks_to_return == 0);

	my $source_file_chunk_date = $source_file_key_to_last_update_date_mapping{$chunk_key};
	my $source_file_chunk_text = &make_text_xml_safe($source_file_key_to_text_mapping{$chunk_key});

	$xml_response .= "    <Chunk key=\"" . &make_text_xml_safe($chunk_key) . "\">\n";
	$xml_response .= "      <SourceFileText date=\"$source_file_chunk_date\">$source_file_chunk_text</SourceFileText>\n";
	$xml_response .= "      <TargetFileText></TargetFileText>\n";
	$xml_response .= "    </Chunk>\n";

	$num_chunks_to_return--;
    }

    $xml_response .= "  </ChunksRequiringTranslation>\n";

    # Then do chunks requiring updating
    if ($num_chunks_to_return > scalar(@target_file_keys_requiring_updating)) {
	$xml_response .= "  <ChunksRequiringUpdating size=\"" . scalar(@target_file_keys_requiring_updating) . "\">\n";
    }
    else {
	$xml_response .= "  <ChunksRequiringUpdating size=\"" . $num_chunks_to_return . "\">\n";
    }

    foreach my $chunk_key (@target_file_keys_requiring_updating) {
	last if ($num_chunks_to_return == 0);

	my $source_file_chunk_date = $source_file_key_to_last_update_date_mapping{$chunk_key};
	my $source_file_chunk_text = &make_text_xml_safe($source_file_key_to_text_mapping{$chunk_key});
	my $target_file_chunk_date = $target_file_key_to_last_update_date_mapping{$chunk_key};
	my $target_file_chunk_text = &make_text_xml_safe($target_file_key_to_text_mapping{$chunk_key});

	$xml_response .= "    <Chunk key=\"" . &make_text_xml_safe($chunk_key) . "\">\n";
	$xml_response .= "      <SourceFileText date=\"$source_file_chunk_date\">$source_file_chunk_text</SourceFileText>\n";
	$xml_response .= "      <TargetFileText date=\"$target_file_chunk_date\">$target_file_chunk_text</TargetFileText>\n";
	$xml_response .= "    </Chunk>\n";

	$num_chunks_to_return--;
    }

    $xml_response .= "  </ChunksRequiringUpdating>\n";

    $xml_response .= "</GTIResponse>\n";
    return $xml_response;
}


sub get_language_status
{
    # The code of the target language (ensure it is lowercase)
    my $target_language_code = lc(shift(@_));

    # Check that the necessary arguments were supplied
    if (!$target_language_code) {
	&throw_fatal_error("Missing command argument.");
    }

    # Form an XML response to the command
    my $xml_response = "<?xml version=\"1.0\" encoding=\"UTF-8\" ?>\n";
    $xml_response .= "<GTIResponse>\n";
    $xml_response .= "  <LanguageStatus code=\"$target_language_code\">\n";

    foreach my $translation_file (@$gti_translation_files) {
	# Get (and check) the translation configuration
	my ($source_file, $target_file, $translation_file_type)
	    = &get_translation_configuration($target_language_code, $translation_file->{'key'});

	# Parse the source language and target language files
	my $source_file_path = &util::filename_cat($gsdl_root_directory, $source_file);
	my @source_file_lines = &read_file_lines($source_file_path);
	my %source_file_key_to_line_mapping = &build_key_to_line_mapping(\@source_file_lines, $translation_file_type);

	my $target_file_path = &util::filename_cat($gsdl_root_directory, $target_file);
	my @target_file_lines = &read_file_lines($target_file_path);
	my %target_file_key_to_line_mapping = &build_key_to_line_mapping(\@target_file_lines, $translation_file_type);

	# Filter out any automatically translated chunks
	foreach my $chunk_key (keys(%source_file_key_to_line_mapping)) {
	    if (&is_chunk_automatically_translated($chunk_key, $translation_file_type)) {
		delete $source_file_key_to_line_mapping{$chunk_key};
		delete $target_file_key_to_line_mapping{$chunk_key};
	    }
	}

	my %source_file_key_to_text_mapping = &build_key_to_text_mapping(\@source_file_lines, \%source_file_key_to_line_mapping, $translation_file_type);
	my %target_file_key_to_text_mapping = &build_key_to_text_mapping(\@target_file_lines, \%target_file_key_to_line_mapping, $translation_file_type);
	&log_message("Number of source chunks: " . scalar(keys(%source_file_key_to_text_mapping)));
	&log_message("Number of target chunks: " . scalar(keys(%target_file_key_to_text_mapping)));

	# Determine the target file chunks requiring translation
	my @target_file_keys_requiring_translation = &determine_chunks_requiring_translation(\%source_file_key_to_text_mapping, \%target_file_key_to_text_mapping);
	&log_message("Number of target chunks requiring translation: " . scalar(@target_file_keys_requiring_translation));

	# Determine the target file chunks requiring updating
	my @target_file_keys_requiring_updating = ();
	if (-e $target_file_path) {
	    my %source_file_key_to_last_update_date_mapping = &build_key_to_last_update_date_mapping($source_file, \@source_file_lines, \%source_file_key_to_line_mapping, $translation_file_type);
	    my %target_file_key_to_last_update_date_mapping = &build_key_to_last_update_date_mapping($target_file, \@target_file_lines, \%target_file_key_to_line_mapping, $translation_file_type);
	    @target_file_keys_requiring_updating = &determine_chunks_requiring_updating(\%source_file_key_to_last_update_date_mapping, \%target_file_key_to_last_update_date_mapping);
	    &log_message("Number of target chunks requiring updating: " . scalar(@target_file_keys_requiring_updating));
	}

	$xml_response .= "    <TranslationFile"
	    . " key=\"" . $translation_file->{'key'} . "\""
	    . " target_file_path=\"" . $target_file . "\""
	    . " num_chunks_translated=\"" . (scalar(keys(%source_file_key_to_text_mapping)) - scalar(@target_file_keys_requiring_translation)) . "\""
	    . " num_chunks_requiring_translation=\"" . scalar(@target_file_keys_requiring_translation) . "\""
	    . " num_chunks_requiring_updating=\"" . scalar(@target_file_keys_requiring_updating) . "\"\/>\n";
    }

    $xml_response .= "  </LanguageStatus>\n";

    $xml_response .= "</GTIResponse>\n";
    return $xml_response;
}


sub search_chunks
{
    # The code of the target language (ensure it is lowercase)
    my $target_language_code = lc(shift(@_));
    # The key of the file to translate (ensure it is lowercase)
    my $translation_file_key = lc(shift(@_));
    # The query string
    my $query_string = join(' ', @_);

    # Check that the necessary arguments were supplied
    if (!$target_language_code || !$translation_file_key || !$query_string) {
	&throw_fatal_error("Missing command argument.");
    }

    # Get (and check) the translation configuration
    my ($source_file, $target_file, $translation_file_type)
	= &get_translation_configuration($target_language_code, $translation_file_key);

    # Parse the source language and target language files
    my $source_file_path = &util::filename_cat($gsdl_root_directory, $source_file);
    my @source_file_lines = &read_file_lines($source_file_path);
    my %source_file_key_to_line_mapping = &build_key_to_line_mapping(\@source_file_lines, $translation_file_type);

    my $target_file_path = &util::filename_cat($gsdl_root_directory, $target_file);
    my @target_file_lines = &read_file_lines($target_file_path);
    my %target_file_key_to_line_mapping = &build_key_to_line_mapping(\@target_file_lines, $translation_file_type);

    # Filter out any automatically translated chunks
    foreach my $chunk_key (keys(%source_file_key_to_line_mapping)) {
	if (&is_chunk_automatically_translated($chunk_key, $translation_file_type)) {
	    delete $source_file_key_to_line_mapping{$chunk_key};
	    delete $target_file_key_to_line_mapping{$chunk_key};
	}
    }

    my %source_file_key_to_text_mapping = &build_key_to_text_mapping(\@source_file_lines, \%source_file_key_to_line_mapping, $translation_file_type);
    my %target_file_key_to_text_mapping = &build_key_to_text_mapping(\@target_file_lines, \%target_file_key_to_line_mapping, $translation_file_type);
    &log_message("Number of source chunks: " . scalar(keys(%source_file_key_to_text_mapping)));
    &log_message("Number of target chunks: " . scalar(keys(%target_file_key_to_text_mapping)));

    # Determine the target file chunks matching the query
    my @target_file_keys_matching_query = ();
    foreach my $chunk_key (keys(%target_file_key_to_text_mapping)) {
	my $target_file_text = $target_file_key_to_text_mapping{$chunk_key};
	if ($target_file_text =~ /$query_string/i) {
	    # &log_message("Chunk with key $chunk_key matches query.");
	    push(@target_file_keys_matching_query, $chunk_key);
	}
    }

    # Form an XML response to the command
    my $xml_response = "<?xml version=\"1.0\" encoding=\"UTF-8\" ?>\n";
    $xml_response .= "<GTIResponse>\n";

    $xml_response .= "  <ChunksMatchingQuery size=\"" . scalar(@target_file_keys_matching_query) . "\">\n";
    foreach my $chunk_key (@target_file_keys_matching_query) {
 	my $target_file_chunk_text = &make_text_xml_safe($target_file_key_to_text_mapping{$chunk_key});

 	$xml_response .= "    <Chunk key=\"$chunk_key\">\n";
 	$xml_response .= "      <TargetFileText>$target_file_chunk_text</TargetFileText>\n";
 	$xml_response .= "    </Chunk>\n";
    }
    $xml_response .= "  </ChunksMatchingQuery>\n";

    $xml_response .= "</GTIResponse>\n";
    return $xml_response;
}


sub submit_translations
{
    # The code of the target language (ensure it is lowercase)
    my $target_language_code = lc(shift(@_));
    # The key of the file to translate (ensure it is lowercase)
    my $translation_file_key = lc(shift(@_));
    # The username of the translation submitter
    my $submitter_username = shift(@_);
    # Whether to submit a target chunk even if it hasn't changed
    my $force_submission_flag = shift(@_);

    # Check that the necessary arguments were supplied
    if (!$target_language_code || !$translation_file_key || !$submitter_username) {
	&log_message("Fatal error (but cannot be thrown): Missing command argument.");
	die "\n";
    }

    # Get (and check) the translation configuration
    my ($source_file, $target_file, $translation_file_type)
	= &get_translation_configuration($target_language_code, $translation_file_key);

    # Parse the source language and target language files
    my @source_file_lines = &read_file_lines(&util::filename_cat($gsdl_root_directory, $source_file));
    my %source_file_key_to_line_mapping = &build_key_to_line_mapping(\@source_file_lines, $translation_file_type);
    my %source_file_key_to_text_mapping = &build_key_to_text_mapping(\@source_file_lines, \%source_file_key_to_line_mapping, $translation_file_type);
    my %source_file_key_to_gti_comment_mapping = &build_key_to_gti_comment_mapping(\@source_file_lines, \%source_file_key_to_line_mapping, $translation_file_type);
    &log_message("Number of source chunks: " . scalar(keys(%source_file_key_to_text_mapping)));

    my @target_file_lines = &read_file_lines(&util::filename_cat($gsdl_root_directory, $target_file));
    my %target_file_key_to_line_mapping = &build_key_to_line_mapping(\@target_file_lines, $translation_file_type);
    my %target_file_key_to_text_mapping = &build_key_to_text_mapping(\@target_file_lines, \%target_file_key_to_line_mapping, $translation_file_type);
    my %target_file_key_to_gti_comment_mapping = &build_key_to_gti_comment_mapping(\@target_file_lines, \%target_file_key_to_line_mapping, $translation_file_type);
    &log_message("Number of target chunks: " . scalar(keys(%target_file_key_to_text_mapping)));

    # Submission date
    my $day = (localtime)[3];
    my $month = ("Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec")[(localtime)[4]];
    my $year = (localtime)[5] + 1900;
    my $submission_date = "$day-$month-$year";

    open(SUBMISSION, "-");
    my @submission_lines = <SUBMISSION>;
    close(SUBMISSION);

    # Remove any nasty carriage returns
    &log_message("Submission:");
    foreach my $submission_line (@submission_lines) {
	$submission_line =~ s/\r$//;
	&log_message("  $submission_line");
    }

    my %source_file_key_to_submission_mapping = ();
    my %target_file_key_to_submission_mapping = ();
    for (my $i = 0; $i < scalar(@submission_lines); $i++) {
	# Read source file part of submission
	if ($submission_lines[$i] =~ /^\<SourceFileText key=\"(.+)\"\>/) {
	    my $chunk_key = $1;

	    # Read the source file text
	    my $source_file_chunk_text = "";
	    $i++;
	    while ($i < scalar(@submission_lines) && $submission_lines[$i] !~ /^\<\/SourceFileText\>/) {
		$source_file_chunk_text .= $submission_lines[$i];
 		$i++;
	    }
	    $source_file_chunk_text =~ s/\n$//;  # Strip the extra newline character added
	    $source_file_chunk_text = &unmake_text_xml_safe($source_file_chunk_text);

	    &log_message("Source file key: $chunk_key");
	    &log_message("Source file text: $source_file_chunk_text");
	    $source_file_key_to_submission_mapping{$chunk_key} = $source_file_chunk_text;
	}

	# Read target file part of submission
	if ($submission_lines[$i] =~ /^\<TargetFileText key=\"(.+)\"\>/) {
	    my $chunk_key = $1;

	    # Read the target file text
	    my $target_file_chunk_text = "";
	    $i++;
	    while ($i < scalar(@submission_lines) && $submission_lines[$i] !~ /^\<\/TargetFileText\>/) {
		$target_file_chunk_text .= $submission_lines[$i];
 		$i++;
	    }
	    $target_file_chunk_text =~ s/\n$//;  # Strip the extra newline character added
	    $target_file_chunk_text = &unmake_text_xml_safe($target_file_chunk_text);

	    &log_message("Target file key: $chunk_key");
	    &log_message("Target file text: $target_file_chunk_text");
	    $target_file_key_to_submission_mapping{$chunk_key} = $target_file_chunk_text;
	}
    }

    # -----------------------------------------
    #   Validate the translation submissions
    # -----------------------------------------

    # Check that the translations are valid
    foreach my $chunk_key (keys(%source_file_key_to_submission_mapping)) {
	# Make sure the submitted chunk still exists in the source file
	if (!defined($source_file_key_to_text_mapping{$chunk_key})) {
	    &log_message("Warning: Source chunk $chunk_key no longer exists (ignoring submission).");
	    delete $source_file_key_to_submission_mapping{$chunk_key};
	    delete $target_file_key_to_submission_mapping{$chunk_key};
	    next;
	}

	# Make sure the submitted source chunk matches the source file chunk
	if ($source_file_key_to_submission_mapping{$chunk_key} ne $source_file_key_to_text_mapping{$chunk_key}) {
	    &log_message("Warning: Source chunk $chunk_key has changed (ignoring submission).");
	    &log_message("Submission source: $source_file_key_to_submission_mapping{$chunk_key}");
	    &log_message("      Source text: $source_file_key_to_text_mapping{$chunk_key}");
	    delete $source_file_key_to_submission_mapping{$chunk_key};
	    delete $target_file_key_to_submission_mapping{$chunk_key};
	    next;
	}
    }

    # Apply the submitted translations
    foreach my $chunk_key (keys(%target_file_key_to_submission_mapping)) {
	# Only apply the submission if it is a change, unless -force_submission has been specified
	if ($force_submission_flag || !defined($target_file_key_to_text_mapping{$chunk_key}) || $target_file_key_to_submission_mapping{$chunk_key} ne $target_file_key_to_text_mapping{$chunk_key}) {
	    $target_file_key_to_text_mapping{$chunk_key} = $target_file_key_to_submission_mapping{$chunk_key};
	    $target_file_key_to_gti_comment_mapping{$chunk_key} = "Updated $submission_date by $submitter_username";
	}
    }

    eval "&write_translated_${translation_file_type}(\$source_file, \\\@source_file_lines, \\\%source_file_key_to_text_mapping, \$target_file, \\\@target_file_lines, \\\%target_file_key_to_text_mapping, \\\%target_file_key_to_gti_comment_mapping, \$target_language_code)";
}


sub get_translation_configuration
{
    # Get the code of the target language
    my $target_language_code = shift(@_);
    # Get the key of the file to translate
    my $translation_file_key = shift(@_);

    # Read the translation data from the gti.cfg file
    my ($source_file, $target_file, $translation_file_type) =
	&get_translation_data_for($target_language_code, $translation_file_key);

    # Check that the file to translate is defined in the gti.cfg file
    if (!$source_file || !$target_file || !$translation_file_type) {
	&throw_fatal_error("Missing or incomplete specification for translation file \"$translation_file_key\" in gti.pl.");
    }

    # Check that the source file exists
    my $source_file_path = &util::filename_cat($gsdl_root_directory, $source_file);
    if (!-e $source_file_path) {
	&throw_fatal_error("Source file $source_file_path does not exist.");
    }

    # Check that the source file is up to date
    # The "2>/dev/null" is very important! If it is missing this will never return when run from the receptionist
    # unless ($translation_file_is_not_in_cvs) {
	my $source_file_cvs_status = `cd $gsdl_root_directory; cvs -d $anonymous_cvs_root update $source_file 2>/dev/null`;
	if ($source_file_cvs_status =~ /^C /) {
	    &throw_fatal_error("Source file $source_file_path conflicts with the repository.");
	}
	if ($source_file_cvs_status =~ /^M /) {
	    &throw_fatal_error("Source file $source_file_path contains uncommitted changes.");
	}
    # }

    return ($source_file, $target_file, $translation_file_type);
}


sub get_translation_data_for
{
    my ($target_language_code, $translation_file_key) = @_;

    foreach my $translation_file (@$gti_translation_files) {
	# If this isn't the correct translation file, move onto the next one
	next if ($translation_file_key ne $translation_file->{'key'});

	# Resolve the target language file
	my $target_language_file = $translation_file->{'target_file'};
	if ($target_language_file =~ /(\{.+\;.+\})/) {
	    my $unresolved_target_language_file_part = $1;

	    # Check for a special case for the target language code
	    if ($unresolved_target_language_file_part =~ /(\{|\;)$target_language_code:([^\;]+)(\;|\})/) {
		my $resolved_target_language_file_part = $2;
		$target_language_file =~ s/$unresolved_target_language_file_part/$resolved_target_language_file_part/;
	    }
	    # Otherwise use the last part as the default value
	    else {
		my ($default_target_language_file_part) = $unresolved_target_language_file_part =~ /([^\;]+)\}/;
		$target_language_file =~ s/$unresolved_target_language_file_part/\{$default_target_language_file_part\}/;		    
	    }
	}

	# Resolve instances of {iso_639_1_target_language_name}
	my $iso_639_1_target_language_name = $iso639::fromiso639{$target_language_code};
	$iso_639_1_target_language_name =~ tr/A-Z/a-z/ if $iso_639_1_target_language_name;
	$target_language_file =~ s/\{iso_639_1_target_language_name\}/$iso_639_1_target_language_name/g;

	# Resolve instances of {target_language_code}
	$target_language_file =~ s/\{target_language_code\}/$target_language_code/g;

	return ($translation_file->{'source_file'}, $target_language_file, $translation_file->{'file_type'});
    }

    return ();
}


sub read_file_lines
{
    my ($file_path) = @_;

    if (!open(FILE_IN, "<$file_path")) {
	&log_message("Note: Could not open file $file_path.");
	return ();
    }
    my @file_lines = <FILE_IN>;
    close(FILE_IN);

    return @file_lines;
}


sub build_key_to_line_mapping
{
    my ($file_lines, $translation_file_type) = @_;
    eval "return &build_key_to_line_mapping_for_${translation_file_type}(\@\$file_lines)";
}


sub build_key_to_text_mapping
{
    my ($file_lines, $key_to_line_mapping, $translation_file_type) = @_;

    my %key_to_text_mapping = ();
    foreach my $chunk_key (keys(%$key_to_line_mapping)) {
	my $chunk_starting_line = (split(/-/, $key_to_line_mapping->{$chunk_key}))[0];
	my $chunk_finishing_line = (split(/-/, $key_to_line_mapping->{$chunk_key}))[1];

	my $chunk_text = @$file_lines[$chunk_starting_line];
	for (my $l = ($chunk_starting_line + 1); $l <= $chunk_finishing_line; $l++) {
	    $chunk_text .= @$file_lines[$l];
	}

	# Map from chunk key to text
	eval "\$key_to_text_mapping{\${chunk_key}} = &import_chunk_from_${translation_file_type}(\$chunk_text)";
    }

    return %key_to_text_mapping;
}


sub build_key_to_last_update_date_mapping
{
    my ($file, $file_lines, $key_to_line_mapping, $translation_file_type) = @_;

    # If the files aren't in CVS then we can't tell anything about what needs updating
    # return () if ($translation_file_is_not_in_cvs);

    # Build a mapping from key to CVS date
    # Need to be careful with this mapping because the chunk keys won't necessarily all be valid
    my %key_to_cvs_date_mapping = &build_key_to_cvs_date_mapping($file, $translation_file_type);

    # Build a mapping from key to comment date
    my %key_to_gti_comment_mapping = &build_key_to_gti_comment_mapping($file_lines, $key_to_line_mapping, $translation_file_type);

    # Build a mapping from key to last update date (the latter of the CVS date and comment date)
    my %key_to_last_update_date_mapping = ();
    foreach my $chunk_key (keys(%$key_to_line_mapping)) {
	# Use the CVS date as a starting point
	my $chunk_cvs_date = $key_to_cvs_date_mapping{$chunk_key};
	$key_to_last_update_date_mapping{$chunk_key} = $chunk_cvs_date;

	# If a comment date exists and it is after the CVS date, use that instead
	my $chunk_gti_comment = $key_to_gti_comment_mapping{$chunk_key};
	if (defined($chunk_gti_comment) && $chunk_gti_comment =~ /(\d?\d-\D\D\D-\d\d\d\d)/) {
	    my $chunk_comment_date = $1;
	    if ((!defined($chunk_cvs_date) || &is_date_after($chunk_comment_date, $chunk_cvs_date))) {
		$key_to_last_update_date_mapping{$chunk_key} = $chunk_comment_date;
	    }
	}
    }

    return %key_to_last_update_date_mapping;
}


sub build_key_to_cvs_date_mapping
{
    my ($filename, $translation_file_type) = @_;

    # Use CVS to annotate each line of the file with the date it was last edited
    # The "2>/dev/null" is very important! If it is missing this will never return when run from the receptionist
    my $cvs_annotated_file = `cd $gsdl_root_directory; cvs -d $anonymous_cvs_root annotate -F $filename 2>/dev/null`;
    my @cvs_annotated_file_lines = split(/\n/, $cvs_annotated_file);

    my @cvs_annotated_file_lines_date = ();
    foreach my $cvs_annotated_file_line (@cvs_annotated_file_lines) {
	# Extract the date from the CVS annotation at the front
	$cvs_annotated_file_line =~ s/^\S+\s+\(\S+\s+(\S+)\):\s//;
	push(@cvs_annotated_file_lines_date, $1);
    }

    # Build a key to line mapping for the CVS annotated file, for matching the chunk key to the CVS date
    my %key_to_line_mapping = &build_key_to_line_mapping(\@cvs_annotated_file_lines, $translation_file_type);

    my %key_to_cvs_date_mapping = ();
    foreach my $chunk_key (keys(%key_to_line_mapping)) {
 	my $chunk_starting_line = (split(/-/, $key_to_line_mapping{$chunk_key}))[0];
 	my $chunk_finishing_line = (split(/-/, $key_to_line_mapping{$chunk_key}))[1];

 	# Find the date this chunk was last edited, from the CVS annotation
 	my $chunk_date = $cvs_annotated_file_lines_date[$chunk_starting_line];
 	for (my $l = ($chunk_starting_line + 1); $l <= $chunk_finishing_line; $l++) {
 	    if (&is_date_after($cvs_annotated_file_lines_date[$l], $chunk_date)) {
 		# This part of the chunk has been updated more recently
 		$chunk_date = $cvs_annotated_file_lines_date[$l];
 	    }
 	}

 	# Map from chunk key to CVS date
 	$key_to_cvs_date_mapping{$chunk_key} = $chunk_date;
    }

    return %key_to_cvs_date_mapping;
}


sub build_key_to_gti_comment_mapping
{
    my ($file_lines, $key_to_line_mapping, $translation_file_type) = @_;

    my %key_to_gti_comment_mapping = ();
    foreach my $chunk_key (keys(%$key_to_line_mapping)) {
	my $chunk_starting_line = (split(/-/, $key_to_line_mapping->{$chunk_key}))[0];
	my $chunk_finishing_line = (split(/-/, $key_to_line_mapping->{$chunk_key}))[1];

	my $chunk_text = @$file_lines[$chunk_starting_line];
	for (my $l = ($chunk_starting_line + 1); $l <= $chunk_finishing_line; $l++) {
	    $chunk_text .= @$file_lines[$l];
	}

	# Map from chunk key to GTI comment
	my $chunk_gti_comment;
	eval "\$chunk_gti_comment = &get_${translation_file_type}_chunk_gti_comment(\$chunk_text)";
	$key_to_gti_comment_mapping{$chunk_key} = $chunk_gti_comment if (defined($chunk_gti_comment));
    }

    return %key_to_gti_comment_mapping;
}


sub determine_chunks_requiring_translation
{
    my $source_file_key_to_text_mapping = shift(@_);
    my $target_file_key_to_text_mapping = shift(@_);

    # Chunks needing translation are those in the source file with no translation in the target file
    my @target_file_keys_requiring_translation = ();
    foreach my $chunk_key (keys(%$source_file_key_to_text_mapping)) {
	if ($source_file_key_to_text_mapping->{$chunk_key} && !$target_file_key_to_text_mapping->{$chunk_key}) {
	    # &log_message("Chunk with key $chunk_key needs translating.");
	    push(@target_file_keys_requiring_translation, $chunk_key);
	}
    }

    return @target_file_keys_requiring_translation;
}


sub determine_chunks_requiring_updating
{
    my $source_file_key_to_last_update_date_mapping = shift(@_);
    my $target_file_key_to_last_update_date_mapping = shift(@_);

    # Chunks needing updating are those in the target file that have been more recently edited in the source file
    my @target_file_keys_requiring_updating = ();
    foreach my $chunk_key (keys(%$source_file_key_to_last_update_date_mapping)) {
	my $source_chunk_last_update_date = $source_file_key_to_last_update_date_mapping->{$chunk_key};
 	my $target_chunk_last_update_date = $target_file_key_to_last_update_date_mapping->{$chunk_key};
	if (defined($target_chunk_last_update_date) && &is_date_after($source_chunk_last_update_date, $target_chunk_last_update_date)) {
	    # &log_message("Chunk with key $chunk_key needs updating.");
	    push(@target_file_keys_requiring_updating, $chunk_key);
 	}
    }

    return @target_file_keys_requiring_updating;
}


sub is_chunk_automatically_translated
{
    my ($chunk_key, $translation_file_type) = @_;
    eval "return &is_${translation_file_type}_chunk_automatically_translated(\$chunk_key)";
}


sub make_text_xml_safe
{
    my $text = shift(@_);
    $text =~ s/\&/\&amp\;/g;
    $text =~ s/\&amp\;lt\;/\&amp\;amp\;lt\;/g;
    $text =~ s/\&amp\;gt\;/\&amp\;amp\;gt\;/g;
    $text =~ s/\&amp\;rarr\;/\&amp\;amp\;rarr\;/g;
    $text =~ s/\&amp\;mdash\;/\&amp\;amp\;mdash\;/g;
    $text =~ s/</\&lt\;/g;
    $text =~ s/>/\&gt\;/g;
    return $text;
}


sub unmake_text_xml_safe
{
    my $text = shift(@_);
    $text =~ s/\&lt\;/</g;
    $text =~ s/\&gt\;/>/g;
    $text =~ s/\&amp\;/\&/g;
    return $text;
}


# Returns 1 if $date1 is after $date2, 0 otherwise
sub is_date_after
{
    my ($date1, $date2) = @_;
    my %months = ("Jan", 1, "Feb", 2, "Mar", 3, "Apr",  4, "May",  5, "Jun",  6,
		  "Jul", 7, "Aug", 8, "Sep", 9, "Oct", 10, "Nov", 11, "Dec", 12);

    my @date1parts = split(/-/, $date1);
    my @date2parts = split(/-/, $date2);

    # Compare year - nasty because we have rolled over into a new century
    my $year1 = $date1parts[2];
    if ($year1 < 80) {
	$year1 += 2000;
    }
    my $year2 = $date2parts[2];
    if ($year2 < 80) {
	$year2 += 2000;
    }

    # Compare year
    if ($year1 > $year2) {
	return 1;
    }
    elsif ($year1 == $year2) {
	# Year is the same, so compare month
	if ($months{$date1parts[1]} > $months{$date2parts[1]}) {
	    return 1;
	}
	elsif ($months{$date1parts[1]} == $months{$date2parts[1]}) {
	    # Month is the same, so compare day
	    if ($date1parts[0] > $date2parts[0]) {
		return 1;
	    }
	}
    }

    return 0;
}


# ==========================================================================================
#   MACROFILE FUNCTIONS

sub build_key_to_line_mapping_for_macrofile
{
    my (@file_lines) = @_;

    my $macro_package;
    my %chunk_key_to_line_mapping = ();
    # Process the contents of the file, line by line
    for (my $i = 0; $i < scalar(@file_lines); $i++) {
	my $line = $file_lines[$i];
	$line =~ s/(\s*)$//;  # Remove any nasty whitespace, carriage returns etc.

	# Check if a new package is being defined
	if ($line =~ m/^package\s+(.+)/) {
	    $macro_package = $1;
	}

	# Line contains a macro name
	elsif ($line =~ m/^(_\w+_)/) {
	    my $macro_key = $1;
	    $line =~ s/\s*([^\\]\#[^\}]+)?$//;  # Remove any comments and nasty whitespace

	    # While there is still text of the macro to go...
	    my $startline = $i;
	    while ($line !~ /\}$/) {
		$i++;
		if ($i == scalar(@file_lines)) {
		    &throw_fatal_error("Could not find end of macro $macro_key.");
		}
		$line = $file_lines[$i];
		$line =~ s/\s*([^\\]\#[^\}]+)?$//;  # Remove any comments and nasty whitespace
	    }

	    # The chunk key consists of the package name and the macro key
	    my $chunk_key = $macro_package . "." . $macro_key;
	    # Map from chunk key to line
	    $chunk_key_to_line_mapping{$chunk_key} = $startline . "-" . $i;
	}

	# Icon: line in format ## "image text" ## image_type ## macro_name ##
	elsif ($line =~ m/^\#\# .* \#\# .* \#\# (.*) \#\#/) {
	    # The chunk key consists of package name and macro key
	    my $chunk_key = $macro_package . "." . $1;
	    # Map from chunk key to line
	    $chunk_key_to_line_mapping{$chunk_key} = $i . "-" . $i;
	}
    }

    return %chunk_key_to_line_mapping;
}


sub import_chunk_from_macrofile
{
    my ($chunk_text) = @_;

    # Is this an icon macro??
    if ($chunk_text =~ /^\#\# (.*)/) {
	# Extract image macro text
	$chunk_text =~ /^\#\#\s+([^\#]+)\s+\#\#/;
	$chunk_text = $1;

	# Remove enclosing quotes
	$chunk_text =~ s/^\"//;
	$chunk_text =~ s/\"$//;
    }

    # No, so it must be a text macro
    else {
	# Remove macro key
	$chunk_text =~ s/^_([^_]+)_(\s*)//;

	# Remove language specifier
	$chunk_text =~ s/^\[l=.*\](\s*)//;

	# Remove braces enclosing text
	$chunk_text =~ s/^{(\s*)((.|\n)*)}(\s*)(\#.+\s*)?/$2/;
    }

    return $chunk_text;
}


sub get_macrofile_chunk_gti_comment
{
    my ($chunk_text) = @_;

    # Check for an "Updated DD-MMM-YYYY" comment at the end of the chunk
    if ($chunk_text =~ /\#\s+(Updated\s+\d?\d-\D\D\D-\d\d\d\d.*)\s*$/i) {
	return $1;
    }

    return undef;
}


sub is_macrofile_chunk_automatically_translated
{
    my ($chunk_key) = @_;

    # The _httpiconX_, _widthX_ and _heightX_ image macros are automatically translated
    if ($chunk_key =~ /\._(httpicon|width|height)/) {
	return 1;
    }

    return 0;
}


# Use the source file to generate a target file that is formatted the same
sub write_translated_macrofile
{
    my $source_file = shift(@_);  # Not used
    my @source_file_lines = @{shift(@_)};
    my $source_file_key_to_text_mapping = shift(@_);
    my $target_file = shift(@_);
    my @target_file_lines = @{shift(@_)};
    my $target_file_key_to_text_mapping = shift(@_);
    my $target_file_key_to_gti_comment_mapping = shift(@_);
    my $target_language_code = shift(@_);

    # Build a mapping from source file line to chunk key
    my %source_file_key_to_line_mapping = &build_key_to_line_mapping_for_macrofile(@source_file_lines);
    my %source_file_line_to_key_mapping = ();
    foreach my $chunk_key (keys(%source_file_key_to_line_mapping)) {
	$source_file_line_to_key_mapping{$source_file_key_to_line_mapping{$chunk_key}} = $chunk_key;
    }
    my @source_file_line_keys = (sort sort_by_line (keys(%source_file_line_to_key_mapping)));
    my $source_file_line_number = 0;

    # Build a mapping from target file line to chunk key
    my %target_file_key_to_line_mapping = &build_key_to_line_mapping_for_macrofile(@target_file_lines);
    my %target_file_line_to_key_mapping = ();
    foreach my $chunk_key (keys(%target_file_key_to_line_mapping)) {
	$target_file_line_to_key_mapping{$target_file_key_to_line_mapping{$chunk_key}} = $chunk_key;
    }
    my @target_file_line_keys = (sort sort_by_line (keys(%target_file_line_to_key_mapping)));

    # Write the new target file
    my $target_file_path = &util::filename_cat($gsdl_root_directory, $target_file);
    if (!open(TARGET_FILE, ">$target_file_path")) {
	&throw_fatal_error("Could not write target file $target_file_path.");
    }

    # Use the header from the target file, to keep language and author information
    if (scalar(@target_file_line_keys) > 0) {
	my $target_file_line_number = 0;
 	my $target_file_chunk_starting_line_number = (split(/-/, $target_file_line_keys[0]))[0];
 	while ($target_file_line_number < $target_file_chunk_starting_line_number) {
	    my $target_file_line = $target_file_lines[$target_file_line_number];
	    last if ($target_file_line =~ /^\# -- Missing translation: /);  # We don't want to get into the macros
 	    print TARGET_FILE $target_file_line;
 	    $target_file_line_number++;
 	}

	$source_file_line_number = (split(/-/, $source_file_line_keys[0]))[0];
    }

    # Model the new target file on the source file, with the target file translations
    foreach my $line_key (@source_file_line_keys) {
 	# Fill in the gaps before this chunk starts
 	my $source_file_chunk_starting_line_number = (split(/-/, $line_key))[0];
 	my $source_file_chunk_finishing_line_number = (split(/-/, $line_key))[1];
 	while ($source_file_line_number < $source_file_chunk_starting_line_number) {
 	    print TARGET_FILE $source_file_lines[$source_file_line_number];
 	    $source_file_line_number++;
 	}
 	$source_file_line_number = $source_file_chunk_finishing_line_number + 1;

	my $chunk_key = $source_file_line_to_key_mapping{$line_key};
	my $source_file_chunk_text = $source_file_key_to_text_mapping->{$chunk_key};
	my $target_file_chunk_text = $target_file_key_to_text_mapping->{$chunk_key} || "";

	my $macrofile_key = $chunk_key;
	$macrofile_key =~ s/^(.+?)\.//;

	# If no translation exists for this chunk, show this, and move on
	if ($source_file_chunk_text ne "" && $target_file_chunk_text eq "") {
	    print TARGET_FILE "# -- Missing translation: $macrofile_key\n";
	    next;
	}

 	# Grab the source chunk text
 	my $source_file_chunk = $source_file_lines[$source_file_chunk_starting_line_number];
 	for (my $l = ($source_file_chunk_starting_line_number + 1); $l <= $source_file_chunk_finishing_line_number; $l++) {
 	    $source_file_chunk .= $source_file_lines[$l];
 	}

 	# Is this an icon macro??
 	if ($source_file_chunk =~ /^\#\# (.*)/) {
 	    # Escape any newline and question mark characters so the source text is replaced correctly
 	    $source_file_chunk_text =~ s/\\/\\\\/g;
	    $source_file_chunk_text =~ s/\?/\\\?/g;

	    # Build the new target chunk from the source chunk
	    my $target_file_chunk = $source_file_chunk;
	    $target_file_chunk =~ s/$source_file_chunk_text/$target_file_chunk_text/;
	    $target_file_chunk =~ s/(\s)*$//;
	    print TARGET_FILE "$target_file_chunk";
 	}

 	# No, it is just a normal text macro
 	else {
 	    print TARGET_FILE "$macrofile_key [l=$target_language_code] {$target_file_chunk_text}";
 	}

	# Add the "updated" comment, if one exists
	if ($target_file_key_to_gti_comment_mapping->{$chunk_key}) {
	    print TARGET_FILE "  # " . $target_file_key_to_gti_comment_mapping->{$chunk_key};
	}
	print TARGET_FILE "\n";
    }

    close(TARGET_FILE);
}


sub sort_by_line
{
    return ((split(/-/, $a))[0] <=> (split(/-/, $b))[0]);
}


# ==========================================================================================
#   RESOURCE BUNDLE FUNCTIONS

sub build_key_to_line_mapping_for_resource_bundle
{
    my (@file_lines) = @_;

    my %chunk_key_to_line_mapping = ();
    for (my $i = 0; $i < scalar(@file_lines); $i++) {
	my $line = $file_lines[$i];
	$line =~ s/(\s*)$//;  # Remove any nasty whitespace, carriage returns etc.

	# Line contains a dictionary string
	if ($line =~ /^(\S+?):(.*)$/) {
	    my $chunk_key = $1;

	    # Map from chunk key to line
	    $chunk_key_to_line_mapping{$chunk_key} = $i . "-" . $i;
	}
    }

    return %chunk_key_to_line_mapping;
}


sub import_chunk_from_resource_bundle
{
    my ($chunk_text) = @_;

    # Simple: just remove string key
    $chunk_text =~ s/^(\S+?):(\s*)//;
    $chunk_text =~ s/(\s*)$//;  # Remove any nasty whitespace, carriage returns etc.
    $chunk_text =~ s/(\s*)\#\s+Updated\s+(\d?\d-\D\D\D-\d\d\d\d.*)\s*$//i;

    return $chunk_text;
}


sub get_resource_bundle_chunk_gti_comment
{
    my ($chunk_text) = @_;

    # Check for an "Updated DD-MMM-YYYY" comment at the end of the chunk
    if ($chunk_text =~ /\#\s+(Updated\s+\d?\d-\D\D\D-\d\d\d\d.*)\s*$/i) {
	return $1;
    }

    return undef;
}


sub is_resource_bundle_chunk_automatically_translated
{
    # No resource bundle chunks are automatically translated
    return 0;
}


sub write_translated_resource_bundle
{
    my $source_file = shift(@_);  # Not used
    my @source_file_lines = @{shift(@_)};
    my $source_file_key_to_text_mapping = shift(@_);
    my $target_file = shift(@_);
    my @target_file_lines = @{shift(@_)};  # Not used
    my $target_file_key_to_text_mapping = shift(@_);
    my $target_file_key_to_gti_comment_mapping = shift(@_);
    my $target_language_code = shift(@_);  # Not used

    # Build a mapping from chunk key to source file line, and from source file line to chunk key
    my %source_file_key_to_line_mapping = &build_key_to_line_mapping_for_resource_bundle(@source_file_lines);
    my %source_file_line_to_key_mapping = ();
    foreach my $chunk_key (keys(%source_file_key_to_line_mapping)) {
	$source_file_line_to_key_mapping{$source_file_key_to_line_mapping{$chunk_key}} = $chunk_key;
    }

    # Write the new target file
    my $target_file_path = &util::filename_cat($gsdl_root_directory, $target_file);
    if (!open(TARGET_FILE, ">$target_file_path")) {
	&throw_fatal_error("Could not write target file $target_file_path.");
    }

    # Model the new target file on the source file, with the target file translations
    my $source_file_line_number = 0;
    foreach my $line_key (sort sort_by_line (keys(%source_file_line_to_key_mapping))) {
 	# Fill in the gaps before this chunk starts
 	my $source_file_chunk_starting_line_number = (split(/-/, $line_key))[0];
 	my $source_file_chunk_finishing_line_number = (split(/-/, $line_key))[1];
 	while ($source_file_line_number < $source_file_chunk_starting_line_number) {
 	    print TARGET_FILE $source_file_lines[$source_file_line_number];
 	    $source_file_line_number++;
 	}
 	$source_file_line_number = $source_file_chunk_finishing_line_number + 1;

	my $chunk_key = $source_file_line_to_key_mapping{$line_key};
	my $source_file_chunk_text = $source_file_key_to_text_mapping->{$chunk_key};
	my $target_file_chunk_text = $target_file_key_to_text_mapping->{$chunk_key} || "";

	# If no translation exists for this chunk, show this, and move on
	if ($source_file_chunk_text ne "" && $target_file_chunk_text eq "") {
	    print TARGET_FILE "# -- Missing translation: $chunk_key\n";
	    next;
	}

	print TARGET_FILE "$chunk_key:$target_file_chunk_text";
	if ($target_file_key_to_gti_comment_mapping->{$chunk_key}) {
	    print TARGET_FILE "  # " . $target_file_key_to_gti_comment_mapping->{$chunk_key};
	}
	print TARGET_FILE "\n";
    }

    close(TARGET_FILE);
}


# ==========================================================================================
#   GREENSTONE XML FUNCTIONS

sub build_key_to_line_mapping_for_greenstone_xml
{
    my (@file_lines) = @_;

    my %chunk_key_to_line_mapping = ();
    for (my $i = 0; $i < scalar(@file_lines); $i++) {
	my $line = $file_lines[$i];
	$line =~ s/(\s*)$//;  # Remove any nasty whitespace, carriage returns etc.

	# Line contains a string to translate
	if ($line =~ /^\s*<Text id=\"(.*?)\">/) {
	    my $chunk_key = $1;
	    $line =~ s/\s*$//;  # Remove any nasty whitespace
	    $line =~ s/<Updated date=\"\d?\d-\D\D\D-\d\d\d\d.*\"\/>$//;

	    # While there is still text of the string to go...
	    my $startline = $i;
	    while ($line !~ /<\/Text>$/) {
		$i++;
		if ($i == scalar(@file_lines)) {
		    &throw_fatal_error("Could not find end of string $chunk_key.");
		}
		$line = $file_lines[$i];
		$line =~ s/\s*$//;  # Remove any nasty whitespace
		$line =~ s/<Updated date=\"\d?\d-\D\D\D-\d\d\d\d.*\"\/>$//;
	    }

	    # Map from chunk key to line
	    if (!defined($chunk_key_to_line_mapping{$chunk_key})) {
		$chunk_key_to_line_mapping{$chunk_key} = $startline . "-" . $i;
	    }
	    else {
		&throw_fatal_error("Duplicate key $chunk_key.");
	    }
	}
    }

    return %chunk_key_to_line_mapping;
}


sub import_chunk_from_greenstone_xml
{
    my ($chunk_text) = @_;

    # Simple: just remove the Text tags
    $chunk_text =~ s/^\s*<Text id=\"(.*?)\">(\s*)//;
    $chunk_text =~ s/<Updated date=\"\d?\d-\D\D\D-\d\d\d\d.*\"\/>$//;
    $chunk_text =~ s/<\/Text>$//;

    return $chunk_text;
}


sub get_greenstone_xml_chunk_gti_comment
{
    my ($chunk_text) = @_;

    # Check for an "Updated DD-MMM-YYYY" comment at the end of the chunk
    if ($chunk_text =~ /<Updated date=\"(\d?\d-\D\D\D-\d\d\d\d.*)\"\/>$/i) {
	return $1;
    }

    return undef;
}


sub is_greenstone_xml_chunk_automatically_translated
{
    # No greenstone XML chunks are automatically translated
    return 0;
}


sub write_translated_greenstone_xml
{
    my $source_file = shift(@_);  # Not used
    my @source_file_lines = @{shift(@_)};
    my $source_file_key_to_text_mapping = shift(@_);
    my $target_file = shift(@_);
    my @target_file_lines = @{shift(@_)};  # Not used
    my $target_file_key_to_text_mapping = shift(@_);
    my $target_file_key_to_gti_comment_mapping = shift(@_);
    my $target_language_code = shift(@_);  # Not used

    # Build a mapping from chunk key to source file line, and from source file line to chunk key
    my %source_file_key_to_line_mapping = &build_key_to_line_mapping_for_greenstone_xml(@source_file_lines);
    my %source_file_line_to_key_mapping = ();
    foreach my $chunk_key (keys(%source_file_key_to_line_mapping)) {
	$source_file_line_to_key_mapping{$source_file_key_to_line_mapping{$chunk_key}} = $chunk_key;
    }

    # Write the new target file
    my $target_file_path = &util::filename_cat($gsdl_root_directory, $target_file);
    if (!open(TARGET_FILE, ">$target_file_path")) {
	&throw_fatal_error("Could not write target file $target_file_path.");
    }

    # Model the new target file on the source file, with the target file translations
    my $source_file_line_number = 0;
    foreach my $line_key (sort sort_by_line (keys(%source_file_line_to_key_mapping))) {
 	# Fill in the gaps before this chunk starts
 	my $source_file_chunk_starting_line_number = (split(/-/, $line_key))[0];
 	my $source_file_chunk_finishing_line_number = (split(/-/, $line_key))[1];
 	while ($source_file_line_number < $source_file_chunk_starting_line_number) {
 	    print TARGET_FILE $source_file_lines[$source_file_line_number];
 	    $source_file_line_number++;
 	}
 	$source_file_line_number = $source_file_chunk_finishing_line_number + 1;

	my $chunk_key = $source_file_line_to_key_mapping{$line_key};
	my $source_file_chunk_text = $source_file_key_to_text_mapping->{$chunk_key};
	my $target_file_chunk_text = $target_file_key_to_text_mapping->{$chunk_key} || "";
	$target_file_chunk_text =~ s/(\n)*$//g;

	# If no translation exists for this chunk, show this, and move on
	if ($source_file_chunk_text ne "" && $target_file_chunk_text eq "") {
	    print TARGET_FILE "<!-- Missing translation: $chunk_key -->\n";
	    next;
	}

	print TARGET_FILE "<Text id=\"$chunk_key\">$target_file_chunk_text</Text>";
	if ($target_file_key_to_gti_comment_mapping->{$chunk_key}) {
	    my $chunk_gti_comment = $target_file_key_to_gti_comment_mapping->{$chunk_key};
	    $chunk_gti_comment =~ s/^Updated //;
	    print TARGET_FILE "<Updated date=\"" . $chunk_gti_comment . "\"\/>";
	}
	print TARGET_FILE "\n";
    }

    # Fill in the end of the file
    while ($source_file_line_number < scalar(@source_file_lines)) {
	print TARGET_FILE $source_file_lines[$source_file_line_number];
	$source_file_line_number++;
    }

    close(TARGET_FILE);
}


&main(@ARGV);