<?php
/*=====================================================================*
|| ###################################################################
|| # Blue Static ISSO Framework
|| # Copyright ©2002-[#]year[#] Blue Static
|| #
|| # 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; version [#]gpl[#] of the License.
|| #
|| # 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.,
|| # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
|| ###################################################################
\*=====================================================================*/

/**
* Graphing System (Graph.php)
*
* @package	ISSO
*/

/**
* Graphing System
*
* This is an abstract class that all other graphing systems extend. It takes
* care of things like scales, data sets, and dimensions.
*
* @author		Blue Static
* @copyright	Copyright (c)2002 - [#]year[#], Blue Static
* @version		$Revision$
* @package		ISSO
*
*/
abstract class BSGraph
{
	/**
	* Graphing data set; 2D array of plot information
	* @var	array
	*/
	protected $dataset = array();
	
	/**
	* Image resource
	* @var	resource
	*/
	protected $image = null;
	
	/**
	* The dimensions of the image
	* @var	array
	*/
	protected $dimensions = array('width' => 550, 'height' => 350);
	
	/**
	* Add a legend to the graph?
	* @var	bool
	*/
	protected $legend = true;
	
	/**
	* Title of the graph
	* @var	string
	*/
	protected $title = 'ISSO Pie Chart';
	
	/**
	* Padding in the graph
	* @var	integer
	*/
	const PADDING = 10;
	
	/**
	* Spacing in the graph
	* @var	integer
	*/
	const SPACING = 4;
	
	// ###################################################################
	/**
	* Constructor
	*/
	public function __construct()
	{
		$this->setScale(0);
	}
	
	// ###################################################################
	/**
	* Sets the width and height by using scale factors of 550x350; you
	* can specify a positive value to multiply by that many times or a
	* negative one to divide
	*
	* @param	float	Scale factor
	*/
	public function setScale($scale)
	{
		$this->dimensions['width'] = 550;
		$this->dimensions['height'] = 350;
		
		if ($scale > 0)
		{
			$this->dimensions['width'] *= $scale;
			$this->dimensions['height'] *= $scale;
		}
		else if ($scale < 0)
		{
			$scale = abs($scale);
			$this->dimensions['width'] /= $scale;
			$this->dimensions['height'] /= $scale;
		}
		
		if (!is_null($this->image))
		{
			imagedestroy($this->image);
		}
		
		$this->image = imagecreate($this->dimensions['width'], $this->dimensions['height']);
	}
	
	// ###################################################################
	/**
	* Sets whether or not a legend is created for the graph
	*
	* @param	bool	Draw a legend?
	*/
	public function setLegend($yesno)
	{
		$this->legend = (bool)$yesno;
	}
	
	// ###################################################################
	/**
	* Sets the title of the chart to be drawn above the graph
	*
	* @param	string	Title of the chart
	*/
	public function setTitle($title)
	{
		$this->title = $title;
	}
	
	// ###################################################################
	/**
	* Graphs the actual data and returns then sends the image result to
	* the output buffer
	*/
	public abstract function graph();
	
	// ###################################################################
	/**
	* Adds an entry to the data set without specifying a color to add.
	* This is the standard method as the color should only be overridden
	* if necessary.
	*
	* @param	string	Data column name
	* @param	integer	Amount
	*/
	public abstract function addDataSet($name, $amount);
	
	// ###################################################################
	/**
	* Adds an entry ot the data set with specifying a color. This works
	* the same as addDataSet() but requires an array() as the 3rd parameter
	* of R,G,B values
	*
	* @param	string	Data column name
	* @param	integer	Percent of 100
	* @param	array	Array of R,G,B values
	*/
	public abstract function addDataSetColor($name, $amount, $color);
	
	// ###################################################################
	/**
	* Fetches a color from the allocated color list and returns the value
	*
	* @return	integer	Allocated color resource
	*/
	protected function _fetchColor()
	{
		static $colorlist = array(
			array(100,	60,		175),
			array(221,	110,	21),
			array(179,	34,		31),
			array(69,	196,	243),
			array(128,	186,	33),
			array(28,	101,	155),
			array(246,	204,	95),
			array(6,	43,		147),
			array(204,	61,		7),
			array(170,	169,	174),
			array(90,	15,		24),
			array(45,	130,	195)
		);
		static $allocated = 0;
		
		$color = $colorlist["$allocated"];
		$allocated++;
		
		return imagecolorallocate($this->image, $color[0], $color[1], $color[2]);
	}
	
	// ###################################################################
	/**
	* Draws a white box, the title, and then a black border around the graph
	*/
	protected function _paintCanvas()
	{
		$colors = $this->_primeColors();
		
		// fill background
		imagefill($this->image, 0, 0, $colors['white']);
		
		// title the chart
		imagestring($this->image, 5, ($this->dimensions['width'] - (imagefontwidth(5) * strlen($this->title))) / 2, self::PADDING, $this->title, $colors['black']);
		
		// draw a border
		imageline($this->image, 0, 0, 0, $this->dimensions['height'], $colors['black']); // left
		imageline($this->image, 0, $this->dimensions['height'] - 1, $this->dimensions['width'], $this->dimensions['height'] - 1, $colors['black']); // bottom
		imageline($this->image, $this->dimensions['width'] - 1, 0, $this->dimensions['width'] - 1, $this->dimensions['height'], $colors['black']); // right
		imageline($this->image, 0, 0, $this->dimensions['width'], 0, $colors['black']); // top
	}
	
	// ###################################################################
	/**
	* Returns an array of colors that are useful (black, white, and grey)
	*
	* @return	array	Colors
	*/
	protected function _primeColors()
	{
		$colors = array();
		$colors['black'] = imagecolorallocate($this->image, 0, 0, 0);
		$colors['white'] = imagecolorallocate($this->image, 255, 255, 255);
		$colors['grey'] = imagecolorallocate($this->image, 121, 121, 123);
		return $colors;
	}
	
	// ###################################################################
	/**
	* Runs the imagepng() function and returns the bytestream
	*
	* @return	string	Byte stream
	*/
	protected function _imageFlush()
	{
		ob_start();
		imagepng($this->image);
		$data = ob_get_contents();
		if ($data === false)
		{
			$data = ob_get_clean();
		}
		ob_clean();
		ob_end_clean();
		return $data;
	}
}

/*=====================================================================*
|| ###################################################################
|| # $HeadURL$
|| # $Id$
|| ###################################################################
\*=====================================================================*/
?>