<?php

# -----------------------------------------------------------------------------
#
# Creates a simple vertical bar graph
#
# -----------------------------------------------------------------------------
#
# Copyright (C) 2004 Christian Eheim
#
# This file is part of TVEz (tvez.sourceforge.net).
#
# TVEz 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.
#
# TVEz 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 TVEz; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
# -----------------------------------------------------------------------------
#
# Created on 02/01/2004 by Christian Eheim (hide@address.com)
#
# LAST MODIFIED:
# $Date: 2004/02/03 00:02:17 $
# $Revision: 1.2 $
# $Author: eheim $
#
# -----------------------------------------------------------------------------

/*
-------------------------------------------------------------------------------
TODO:
	- In the gradient, the bar spacing is off by a little bit
-------------------------------------------------------------------------------
*/


include("Graph.php");

class BarGraph extends Graph {
	
	var $_sum;

	var $_barSpacing;
	var $_barBorder;
	var $_gradient;

	var $_graphLeft;
	var $_graphTop;
	var $_graphWidth;
	var $_graphHeight;

	function BarGraph($width,$height,$title=null) {
		# Instantiate the base class
		$this->Graph($width,$height,$title);

		# Set the base class properties
		$this->legend_show(false);
		$this->set_label_type("percent");
		$this->set_bgcolor("#dddddd");
		
		$this->set_margin(1,5,1,1);
		$this->_barSpacing	= 5;
		$this->_barBorder	= true;
		$this->_borderColor	= "black";
		$this->_gradient	= true;
		$this->set_x_axis_title_margin(3);
		$this->set_y_axis_title_margin(3);
	}

	function set_bar_spacing($val) {
		$this->_barSpacing = $val;
	}
	function set_bar_gradient($bool) {
		$this->_gradient = $bool;
	}
	function set_bar_border_color($col) {
		$this->_borderColor = $col;
	}
	function show_bar_border($bool) {
		$this->_barBorder = $bool;
	}

	#
	# Generate the legend items
	# There is no legend for a bar graph
	#
	function generate_legend() {
		;
	}
	#
	# Generate the axes
	#
	function generate_axes() {

		list($min,$max) = $this->minmax();
		list($lx,$ly) = $this->get_longest();

		if ($this->get_y_axis_min_value() === "unset")
			$this->set_y_axis_min_value($min);
		if ($this->get_y_axis_max_value() === "unset")
			$this->set_y_axis_max_value($max);

		if (! $this->get_x_axis_num_ticks()) {
			$l = array();
			foreach ($this->_data as $label => $value) {
				array_push($l,$label);
			}
			$this->set_x_axis_labels($l);
		}
		else {
			# This is not good
			$lx = $this->get_x_axis_min_value();
		}

		$this->set_x_axis_longest($lx);
		$this->set_y_axis_longest($ly);
	}
	#
	# Draw the Bar Graph
	#
	function create_graph() {

		$min = $this->get_y_axis_min_value();
		$max = $this->get_y_axis_max_value();
		$this->_sum = $this->sum();
		
		$this->compute();

		$count = count($this->_data);
		# Compute the bar width
		$bwidth = ($this->_graphWidth - ($count)*$this->_barSpacing) / $count;

		$left = ($this->_barSpacing/2+$this->_graphLeft);
		foreach ($this->_data as $label => $value) {
			$top = $this->_graphTop + $this->_graphHeight
					- round((($value-$min)/($max-$min))*$this->_graphHeight);
			if ($top > $this->_graphTop+$this->_graphHeight-1)
				$top = $this->_graphTop+$this->_graphHeight;

			# The bar spacing is off a little bit???
			if ($this->_gradient) { // Draw the bars with gradient
				$dg = 255/($bwidth/3);
				for ($i=0; $i<($bwidth/3); $i++) {
					$shade = round($dg*$i);
					$this->draw_line(
						$shade, $shade, 255,
						$left+$i,$top, $this->_graphTop+$this->_graphHeight-1);
				}
				$dg = 255/(2*$bwidth/3);
				for ($i=$bwidth/3; $i<($bwidth-1); $i++) {
					$shade = 255-round($dg*($i-$bwidth/3));
					$this->draw_line(
						$shade, $shade, 255,
						$left+$i,$top, $this->_graphTop+$this->_graphHeight-1);
				}
			} else { // Solid
				$this->draw_box(0,0,255,$left,$left+$bwidth-1,$top,$this->_graphTop+$this->_graphHeight-1);
			}

			if ($this->_barBorder) {
				$this->draw_border(0,0,255,$left,$left+$bwidth-1,$top,$this->_graphTop+$this->_graphHeight-1);
			}

			$left += $bwidth+$this->_barSpacing;	
		}
	}
	# Draws a filled box
	function draw_box($r,$g,$b,$left,$right,$top,$bottom) {
		# If the color already exists, don;t allocate it again
		$color = imagecolorexact($this->_image->_image,
					$r, $g, $b);
		if ($color==-1)
			$color = $this->_image->_rgb->allocate_color(
				array( $r, $g, $b ) );
		ImageFilledRectangle(
			$this->_image->_image,
			$left, $top,
			$right, $bottom,
			$color
		);
	}
	# Draws a border box
	function draw_border($r,$g,$b,$left,$right,$top,$bottom) {
		# If the bar does not have any height, return
		if ($top == $this->_graphTop+$this->_graphHeight) return;
		# If the color already exists, don;t allocate it again
		$color = $this->_image->_rgb->allocate_color(
				$this->_borderColor );
		ImageLine(
			$this->_image->_image,
			$left, $top,
			$left, $bottom,
			$color
		);
		ImageLine(
			$this->_image->_image,
			$right, $top,
			$right, $bottom,
			$color
		);
		ImageLine(
			$this->_image->_image,
			$left, $top,
			$right, $top,
			$color
		);
	}
	# Draws a vertical line
	function draw_line($r,$g,$b,$left,$top,$bottom) {
		# If the color already exists, don;t allocate it again
		$color = imagecolorexact($this->_image->_image,
					$r, $g, $b);
		if ($color==-1)
			$color = $this->_image->_rgb->allocate_color(
				array( $r, $g, $b ) );
		ImageFilledRectangle(
			$this->_image->_image,
			$left, $top,
			$left+1, $bottom,
			$color
		);
	}
	#
	# Compute the center and size
	#
	function compute() {
		list(
			$this->_graphLeft, $this->_graphTop,
			$this->_graphWidth, $this->_graphHeight
		) = $this->_image->get_graph_area();

	}
}

?>