# 
# PERL mapweaver module by gary68
#
#
#
#
# Copyright(C)2011, Gerhard Schwanz
#
# 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 3 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, see <http://www.gnu.org/licenses/>
#


package mwOccupy; 

use strict;
use warnings;

use List::Util qw[min max];

use mwMap;

use vars qw($VERSION @ISA @EXPORT @EXPORT_OK);

require Exporter;

@ISA = qw(Exporter AutoLoader);

@EXPORT = qw(boxOccupyLines
		boxOccupyArea
		boxLinesOccupied
		boxAreaOccupied
		boxDrawOccupiedAreas
	);


my $boxSize = 5;

my %box =();


# -------------------------------------------------------------

sub boxOccupyLines{	my($refCoords, $buffer, $value)= @_;
	my @coordinates = @$refCoords;
	my @lines =();

	for(my $i = 0; $i < $#coordinates-2; $i += 2){		push @lines, [$coordinates[$i], $coordinates[$i+1], $coordinates[$i+2], $coordinates[$i+3]];
}
	foreach my $line(@lines){		my $x1 = $line->[0];
		my $y1 = $line->[1];
		my $x2 = $line->[2];
		my $y2 = $line->[3];


		# print "$x1, $y1, $x2, $y2\n";

		if($x1 != $x2){
			my $m =($y2 - $y1)/($x2 - $x1);
			my $b = $y1 - $m * $x1;

			if(abs($x1 - $x2)> abs($y1 - $y2)){
				# calc points on x axis
				my $x = $x1;
				my $stepX = $boxSize;
				if($x2 < $x1){$stepX = - $boxSize;}				while(($x >= min($x1, $x2))and($x <= max($x1, $x2))){
					my $y = $m * $x + $b;

					# ACTUAL COORDINATE $x, $y
					my $ax1 = $x - $buffer;
					my $ax2 = $x + $buffer;
					my $ay1 = $y - $buffer;
					my $ay2 = $y + $buffer;
					boxOccupyArea($ax1, $ay1, $ax2, $ay2, 0, $value);
					$x += $stepX;	
			}
		}			else{	

				# calc points on y axis
				my $y = $y1;
				my $stepY = $boxSize;
				if($y2 < $y1){$stepY = - $boxSize;}				while(($y >= min($y1, $y2))and($y <= max($y1, $y2))){
					my $x =($y - $b)/ $m;

					# ACTUAL COORDINATE $x, $y
					my $ax1 = $x - $buffer;
					my $ax2 = $x + $buffer;
					my $ay1 = $y - $buffer;
					my $ay2 = $y + $buffer;
					boxOccupyArea($ax1, $ay1, $ax2, $ay2, 0, $value);

					$y += $stepY;	
			}
		}# abs	

	}		else{			my $x = $x1;

			# calc points on y axis
			my $y = $y1;
			my $stepY = $boxSize;
			if($y2 < $y1){$stepY = - $boxSize;}			while(($y >= min($y1, $y2))and($y <= max($y1, $y2))){
				# ACTUAL COORDINATE $x, $y
				my $ax1 = $x - $buffer;
				my $ax2 = $x + $buffer;
				my $ay1 = $y - $buffer;
				my $ay2 = $y + $buffer;
				boxOccupyArea($ax1, $ay1, $ax2, $ay2, 0, $value);

				$y += $stepY;	
		}	}

}}

sub boxLinesOccupied{	my($refCoords, $buffer)= @_;
	my @coordinates = @$refCoords;
	my @lines =();
	my $result = 0;

	for(my $i = 0; $i < $#coordinates-2; $i += 2){		push @lines, [$coordinates[$i], $coordinates[$i+1], $coordinates[$i+2], $coordinates[$i+3]];
}
	foreach my $line(@lines){		my $x1 = $line->[0];
		my $y1 = $line->[1];
		my $x2 = $line->[2];
		my $y2 = $line->[3];


		# print "$x1, $y1, $x2, $y2\n";

		if($x1 != $x2){
			my $m =($y2 - $y1)/($x2 - $x1);
			my $b = $y1 - $m * $x1;

			if(abs($x1 - $x2)> abs($y1 - $y2)){
				# calc points on x axis
				my $x = $x1;
				my $stepX = $boxSize;
				if($x2 < $x1){$stepX = - $boxSize;}				while(($x >= min($x1, $x2))and($x <= max($x1, $x2))){
					my $y = $m * $x + $b;

					# ACTUAL COORDINATE $x, $y
					my $ax1 = $x - $buffer;
					my $ax2 = $x + $buffer;
					my $ay1 = $y - $buffer;
					my $ay2 = $y + $buffer;
					my $tmp = boxAreaOccupied($ax1, $ay1, $ax2, $ay2);
					if($tmp > $result){$result = $tmp;}					$x += $stepX;	
			}
		}			else{	

				# calc points on y axis
				my $y = $y1;
				my $stepY = $boxSize;
				if($y2 < $y1){$stepY = - $boxSize;}				while(($y >= min($y1, $y2))and($y <= max($y1, $y2))){
					my $x =($y - $b)/ $m;

					# ACTUAL COORDINATE $x, $y
					my $ax1 = $x - $buffer;
					my $ax2 = $x + $buffer;
					my $ay1 = $y - $buffer;
					my $ay2 = $y + $buffer;
					my $tmp = boxAreaOccupied($ax1, $ay1, $ax2, $ay2);
					if($tmp > $result){$result = $tmp;}
					$y += $stepY;	
			}
		}# abs	

	}		else{			my $x = $x1;

			# calc points on y axis
			my $y = $y1;
			my $stepY = $boxSize;
			if($y2 < $y1){$stepY = - $boxSize;}			while(($y >= min($y1, $y2))and($y <= max($y1, $y2))){
				# ACTUAL COORDINATE $x, $y
				my $ax1 = $x - $buffer;
				my $ax2 = $x + $buffer;
				my $ay1 = $y - $buffer;
				my $ay2 = $y + $buffer;
				my $tmp = boxAreaOccupied($ax1, $ay1, $ax2, $ay2);
				if($tmp > $result){$result = $tmp;}
				$y += $stepY;	
		}	}

}	return $result; 
}

# -------------------------------------------------------------

sub boxOccupyArea{	my($x1, $y1, $x2, $y2, $buffer, $value)= @_;

	if($x2 < $x1){		my $tmp = $x1;
		$x1 = $x2;
		$x2 = $tmp;
}	if($y2 < $y1){		my $tmp = $y1;
		$y1 = $y2;
		$y2 = $tmp;
}
	$x1 -= $buffer;
	$x2 += $buffer;
	$y1 -= $buffer;
	$y2 += $buffer;

	for(my $x = $x1; $x <= $x2; $x += $boxSize){		for(my $y = $y1; $y <= $y2; $y += $boxSize){			my $bx = int($x / $boxSize);
			my $by = int($y / $boxSize);
			$box{$bx}{$by}= $value;
			# print "box $bx, $by occupied\n";
	}}
	return;
}

sub boxAreaOccupied{	my($x1, $y1, $x2, $y2)= @_;
	my $result = 0;

	if($x2 < $x1){		my $tmp = $x1;
		$x1 = $x2;
		$x2 = $tmp;
}	if($y2 < $y1){		my $tmp = $y1;
		$y1 = $y2;
		$y2 = $tmp;
}
	for(my $x = $x1; $x <= $x2; $x += $boxSize){		my $bx = int($x / $boxSize);
		for(my $y = $y1; $y <= $y2; $y += $boxSize){			my $by = int($y / $boxSize);
			# print "  $bx, $by\n";
			if(defined $box{$bx}{$by}){				if($box{$bx}{$by}> $result){					# print "check box $bx, $by\n";
					$result = $box{$bx}{$by};
			}		}	}}	return $result;
}

# -------------------------------------------------------------


sub boxDrawOccupiedAreas{	my $format1 = "fill=\"red\" fill-opacity=\"0.3\" ";
	my $format2 = "fill=\"blue\" fill-opacity=\"0.3\" ";
	my $format3 = "fill=\"green\" fill-opacity=\"0.5\" ";
	foreach my $bx(sort{$a <=> $b}keys %box){		foreach my $by(sort{$a <=> $b}keys %{$box{$bx}}){			my $x1 = $bx * $boxSize;
			my $x2 = $x1 + $boxSize;
			my $y1 = $by * $boxSize;
			my $y2 = $y1 + $boxSize;

			if($box{$bx}{$by}== 1){				drawRect($x1, $y1, $x2, $y2, 0, $format1, "occupied");
		}			elsif($box{$bx}{$by}== 2){				drawRect($x1, $y1, $x2, $y2, 0, $format2, "occupied");
		}			else {				drawRect($x1, $y1, $x2, $y2, 0, $format3, "occupied");
		}			# print "occupied $bx, $by\n";
	}}
}

1;