#!/usr/bin/perl
use Image::ExifTool;
use POSIX;
use AppConfig;
use Getopt::Long;
use strict;

# TODO: filename.txt for file comments
# TODO: Templating of EXIF
# TODO: Priority/sorting of EXFI tags
# TODO: Possibility for hide/show EXIF
# TODO: RSS support? Delegate that to frontend?
# TODO: Save reference to main-index thumbnail.
# TODO: Clear old generated files and meta on regen
# TODO: Use perlmagick et. al instead of convert/jhead..

# Runtime data
my $title = undef;
my $htmlonly = 0;
my $configfile = undef;
my $halp = undef;

GetOptions (
	"title=s"	=> \$title,
	"htmlonly!"	=> \$htmlonly,
	"config=s"	=> \$configfile,
	"help"		=> \$halp
);
if ( $halp )
{
	print "\nplsgen version 0.1\n";
	print "Copyright Jon Langseth, BSD lisence\n\n";
	print " --title='Your album title'\n";
	print "     Sets the album title. Title will be stored in .title\n";
	print "     If no title is given, it will be read from .title, if present\n";
	print " --htmlonly\n";
	print "     Add this option to only generate HTML files\n";
	print "     No image operations will be performed with this option\n";
	print " --config=/path/to/config\n";
	print "     Overrides default config file location.\n";
	print "     Default is to look for ./plsgen.cfg, then ../plsgen.cfg\n";
	print "     and finally /etc/plsgen.cfg.\n";
	print "\n";
	exit;
}

# Configuration data
my $config = get_config( $configfile );
my $full_tpl_file 	= $config->full_tpl_file;
my $index_tpl_file 	= $config->index_tpl_file;
my $css_file 		= $config->css_file;
my $navigation_script 	= $config->navigation_script;
my $columns 		= $config->columns;
my $rows 		= $config->rows;
my $thumb_pre 		= $config->thumb_pre;
my $thumb_post 		= $config->thumb_post;
my $idx_prev_text 	= $config->idx_prev_text;
my $idx_next_text 	= $config->idx_next_text;
my $idx_ret_text 	= $config->idx_ret_text;
my $footer_tag 		= $config->footer_tag;

# Get or save the title, depending..
if ( (not $title) && ( -f ".title" ) )
{
	open TF, "<.title";
	$title = <TF>;
	chomp($title);
	close TF;
}
elsif ( $title )
{
	open TF, ">.title";
	print TF $title . "\n";
	close TF;
}

mkdir "thumb";
mkdir "view";

# Glob file names to an array
my @images = glob("*png *.jpg *.JPG *.gif *.GIF");
# Keep count of total number of images
my $imagecount = $#images;

my ($current, $previous, $next);
my $indexcount = 1;
my $indexfile;

my $main_meta = "<link rel='stylesheet' href='" . $css_file . "' type='text/css' />";
my $navigation_header = "<script type='text/javascript' src='" . $navigation_script . "'></script>";

my $thumbs = "<div class='thumbnails'>";

my $indexes = ceil( $imagecount/($rows*$columns) );
my $gentime = localtime;

# In groups of N ( X rows x Y colums of index):
# - Step through image array:
for ( my $i = 1; $i <= $imagecount; $i++)
{
	$current = $images[$i-1];
# - -   Previous image is previous location in array, unless cur=first
	$previous = $images[$i-2] if $i > 1;
	$previous = undef if  $i == 1;
# - -   Next image is next location in array, unless cur=last.
	$next = $images[$i] if $i < ( $imagecount);
	$next = undef if $i >= ( $imagecount);

	#Set up text-strings for template replacement
	if ( $indexcount == 1 ) { $indexfile = "index.html"; } 
	else { $indexfile = "index" . $indexcount . ".html"; }
	my $navscript = gen_navscript( $previous, $next, $indexfile );
	my $position = $i . " of " . $imagecount;
	my $prev_text = "<a href='" . $previous . ".html'><img src='thumb/" . $previous . "' /></a>";
	my $next_text = "<a href='" . $next . ".html'><img src='thumb/" . $next . "' /></a>";
	my $cur_index_text = "<a href='". $indexfile ."'>" . $idx_ret_text . "</a>";
	my $current_display = "view/" . $current;

	printf ("Processing image %s: %s\n", $position, $current);

# - - If rotated according to EXIF, do rotation
	my $exif = get_exifdata( $current );
	if ( $exif->{'Orientation'} =~ m/rotate/i )
	{
		system("jhead -autorot " . $current . ">/dev/null") unless $htmlonly;
	}
	my $exif_text = get_exifblock($exif);

# - - Create thumbnail image (resize to new image)
	system("convert " . $current . " -geometry '160x120>' thumb/" . $current) unless $htmlonly;
# - - Create normal display image (resize to new image)
	system("convert " . $current . " -geometry '800x600>' view/" . $current) unless $htmlonly;

# - - Create full view HTML file
	my $cur_html;
	open TEMPLATE, "<" . $full_tpl_file or die "UNABLE TO LOAD TEMPLATE $full_tpl_file\n";
	while (<TEMPLATE>)
	{
		if ( $previous ) { $_ =~ s/%\{previous\}/$prev_text/; } 
		else { $_ =~ s/%\{previous\}//; } 

		if ( $next ) { $_ =~ s/%\{next\}/$next_text/; }
		else { $_ =~ s/%\{next\}//; }

		$_ =~ s/%\{index\}/$cur_index_text/;
		$_ =~ s/%\{title\}/$title/;
		$_ =~ s/%\{main_meta\}/$main_meta/;
		$_ =~ s/%\{navigation_script\}/$navigation_header/;
		$_ =~ s/%\{position\}/$position/;
		$_ =~ s/%\{current\}/$current/;
		$_ =~ s/%\{current_display\}/$current_display/;
		$_ =~ s/%\{exif\}/$exif_text/;
		$_ =~ s/%\{gallery_timestamp\}/$gentime/;
		$_ =~ s/%\{navscript\}/$navscript/;
		$_ =~ s/%\{footer_tag\}/$footer_tag/;
		$cur_html .= $_;
	}
	close TEMPLATE;
	open HTML, ">" . $current . ".html" or die "UNABLE TO WRITE\n";
	print HTML $cur_html;
	close HTML;

# - -   Append image thumbnail code to current index content
	$thumbs .= $thumb_pre . "<a href='" . $current . ".html'><img src='thumb/" . $current . "' /></a>" . $thumb_post;
	if ( $i % ($rows*$columns) == 0 )
	{
		$thumbs .= "</div>";
# - - On each Y, terminate index file/group:
		make_index( $index_tpl_file, $indexcount, $indexes, $thumbs);
		$thumbs = "<div class='thumbnails'>";
		$indexcount++;
	}
	elsif ( $i % ($columns) == 0 )
	{
# - - On each X, terminate index content row 
		$thumbs .= "\n</div>\n<div class='thumbnails'>";
	}
}
$thumbs .= "</div>";
make_index( $index_tpl_file, $indexcount, $indexes, $thumbs);
# Done.


# -------------- Functions supporting above code -----------------------
sub make_index
{
	my $tpl = shift;
	my $idxcount = shift;
	my $lastidx = shift;
	my $thumbs = shift;

	my $gentime = localtime;
	my $html;

	my $prev_file;
	my $prev_text;
	my $next_file;
	my $next_text;
	my $indexfile;

	# If index counter is 1, filename is index.html
	$indexfile = ( $indexcount ==1 ) ? "index.html" : "index" . $idxcount . ".html";

	# If index counter is > 1, add previous index link.
	if ( $idxcount > 1 ) 
	{
		$prev_file = "index" . ($idxcount-1) . ".html";
		$prev_file = "index.html" if ( $idxcount == 2 );
		$prev_text = "<a href='$prev_file'>" . $idx_prev_text . "</a>";
	} 

	# If current image is last in array, do not add nex-index link
	if ( $idxcount < $lastidx ) 
	{
		$next_file = "index" . ($idxcount+1) . ".html";
		$next_text = "<a href='" . $next_file . "'>" . $idx_next_text . "</a>";
	}

	my $position = $indexcount . " of " . $lastidx;
	my $navscript = gen_navscript( $prev_file, $next_file );

	open TEMPLATE, "<" . $tpl or die "UNABLE TO LOAD TEMPLATE\n";
	while (<TEMPLATE>)
	{
		$_ =~ s/%\{previous\}/$prev_text/;
		$_ =~ s/%\{next\}/$next_text/;
		$_ =~ s/%\{title\}/$title/;
		$_ =~ s/%\{position\}/$position/;
		$_ =~ s/%\{main_meta\}/$main_meta/;
		$_ =~ s/%\{navigation_script\}/$navigation_header/;
		$_ =~ s/%\{thumbnails\}/$thumbs/;
		$_ =~ s/%\{gallery_timestamp\}/$gentime/;
		$_ =~ s/%\{navscript\}/$navscript/;
		$_ =~ s/%\{footer_tag\}/$footer_tag/;
		$html .= $_;
	}
	close TEMPLATE;
	open HTML, ">" . $indexfile or die "UNABLE TO WRITE\n";
	print HTML $html;
	close HTML;

}

sub get_exifdata ($)
{
	my $image = shift;
	my $exifTool = new Image::ExifTool;
	$exifTool->Options(Unknown => 1);

	my $exif;
    	my $info = $exifTool->ImageInfo($image);
	$exif->{'Make'} = $info->{'Make'};
	$exif->{'Model'} = $info->{'Model'};
	#$exif->{'Orientation'} = $info->{'Orientation'};
	$exif->{'ExposureTime'} = $info->{'ExposureTime'};
	$exif->{'FNumber'} = $info->{'FNumber'};
	$exif->{'ISO'} = $info->{'ISO'};
	$exif->{'CreateDate'} = $info->{'CreateDate'};
	$exif->{'ExposureCompensation'} = $info->{'ExposureCompensation'};
	$exif->{'Flash'} = $info->{'Flash'};
	$exif->{'FocalLength'} = $info->{'FocalLength'};
	#$exif->{'ColorSpace'} = $info->{'ColorSpace'};
	#$exif->{'FileSource'} = $info->{'FileSource'};
	$exif->{'ExposureMode'} = $info->{'ExposureMode'};
	$exif->{'Macro'} = $info->{'Macro'};
	$exif->{'LensType'} = $info->{'LensType'};
	return $exif;
}

sub get_exifblock 
{
	my $exif = shift;
	my $exifTool = new Image::ExifTool;
	my $block = "<table id='exifdata' cellspacing='0'>\n";
	$block .= "<tr class='exifhead'><td>EXIF Parameter</td><td>Value</td></tr>\n";
	my $tagcount = 0;
	my $flipflop = 0;
	foreach my $tag ( keys %$exif )
	{
		my $val = $exif->{$tag};
		next unless $val;
		$block .= "<tr class='exiflight'>" if $flipflop;
		$block .= "<tr class='exifdark'>"  if not $flipflop;
		$block .= "\t<td>";
		$block .= $exifTool->GetDescription($tag);
		$block .= "</td>\n";
		$block .= "\t<td>";
		$block .= $val;
		$block .= "</td>\n";
		$block .= "</tr>\n";
		$flipflop = not $flipflop;
		$tagcount++;
	}
	$block .= "</table>";
	$block = undef if not $tagcount;
	return $block;
}

sub gen_navscript
{
	my $prev = shift;
	my $next = shift;
	my $index = shift;

	$prev =~ s/\.html//;
	$next =~ s/\.html//;

	my $scriptbuffer = "<script type='text/javascript'>\n";
	$scriptbuffer .= "\tnav_reg_prev('" . $prev . "');\n" if $prev;
	$scriptbuffer .= "\tnav_reg_next('" . $next . "');\n" if $next;
	$scriptbuffer .= "\tnav_reg_index('" . $index . "');\n" if $index;
	$scriptbuffer .= "\tnav_reg_onkeypress();\n";
	$scriptbuffer .= "</script>\n";
	return $scriptbuffer;
}

sub get_config
{
	# My standard way of implementing AppConfig use ...
	my $filename = shift;
	if ( not $filename )
	{
		my @files = ( "./plsgen.cfg", "../plsgen.cfg", "/etc/plsgen.cfg" );
		foreach my $file ( @files ) {
			$filename = $file;
			last if ( -f $filename );
		}
	}

	my $cfg = AppConfig->new(
		{
		    CASE   => 1,
		    ERROR  => \&cfg_error,
		    GLOBAL => {
			DEFAULT  => "<unset>",
			ARGCOUNT => AppConfig::ARGCOUNT_ONE
		    },
		}

	);
	$cfg->define('full_tpl_file');
	$cfg->full_tpl_file("/usr/local/share/plsgen/full.tpl");
	$cfg->define('index_tpl_file');
	$cfg->index_tpl_file("/usr/local/share/plsgen/index.tpl");
	$cfg->define('css_file');
	$cfg->css_file("../style.css");
	$cfg->define('navigation_script');
	$cfg->navigation_script("../nav.js");
	$cfg->define('columns');
	$cfg->columns(4);
	$cfg->define('rows');
	$cfg->rows(3);
	$cfg->define('thumb_pre');
	$cfg->thumb_pre("<div class='thumb'>");
	$cfg->define('thumb_post');
	$cfg->thumb_post("</div>");
	$cfg->define('idx_prev_text');
	$cfg->idx_prev_text("&larr; Back");
	$cfg->define('idx_next_text');
	$cfg->idx_next_text("Next &rarr;");
	$cfg->define('idx_ret_text');
	$cfg->idx_ret_text("To index");
	$cfg->define('footer_tag');
	$cfg->footer_tag('plsgen : Perl Simple Gallery Generator 0.1');

	$cfg->file($filename) if -f $filename;
	return $cfg;
}

sub cfg_error {
    die "Error occured in config-handling: $_\n";
}