<?php

class Image
{
	/**
	* Info about the source image
	**/
	private $srcImage 	= "";
	private $srcWidth 	= 0;
	private $srcHeight 	= 0;
	private $srcType 	= "";
	
	/**
	* Info about the new image
	**/
	private $newImage 	= "";
	private $newWidth 	= 0;
	private $newHeight 	= 0;
	private $newType 	= "";
	
	/**
	*
	**/
	private $rscImg;
	
	/**
	* Constructor
	**/
	function __construct($fileName)
	{
		$this->srcImage = $fileName;
		$infos = getimagesize($fileName);
		$this->srcWidth 	= $infos[0];
		$this->srcHeight 	= $infos[1];
		$this->srcType 	= $infos[2];
	}
	
	/**
	* Setters
	**/
	function setNewImage($newName) 		{ $this->newImage = $newName; }
	function setNewWidth($newWidth) 	{ $this->newWidth = $newWidth; }
	function setNewHeight($newHeight) 	{ $this->newHeight = $newHeight; }
	
	/**
	* Resize an image without using any kind of specific resizing (crop, ration, etc ...)
	*
	* @param string $name
	* @param integer $width
	* @param integer $height
	* @param string $type
	* @param string $from
	* @return bool
	*/
	function hardResize($name, $width, $height, $type = "jpg", $from = "")
	{
		$this->setNewImage($name);
		$this->setNewWidth($width);
		$this->setNewHeight($height);
		
		if(empty($from))
		{
			if(empty($this->srcImage)) return false;
			$from = $this->srcImage;
		}
		$this->getImageRessource($from);
		
		$thumb = imagecreatetruecolor($this->newWidth, $this->newHeight);
		
		if(!imagecopyresampled($thumb, $this->rscImg, 0, 0, 0, 0, 
								$this->newWidth, $this->newHeight, $this->srcWidth, $this->srcHeight))
			throw new Exception("Impossible de redimensionner l'image");
		
		switch($type)
		{
			case 'jpg':
			case 'jpeg':
				return imagejpeg($thumb, $name, 100);
			break;
			
			case 'gif':
				return imagegif($thumb, $name);
			break;
			
			case 'png':
				return imagepng($thumb, $name);
			break;
			
			default:
				throw new Exception("Impossible de créer la nouvelle image le type $type ne convient pas");
		}
	}
	
	/**
	*  Prepare an image ressource
	*
	* @param string $from
	**/
	function getImageRessource($from)
	{
		$infos = getimagesize($from);
		switch($infos[2])
		{
			case IMG_GIF:
				$this->rscImg = imagecreatefromgif($from);
			break;
			
			case IMG_JPG:
			case IMG_JPEG:
				$this->rscImg = imagecreatefromjpeg($from);
			break;
			
			case IMG_PNG:
				$this->rscImg = imagecreatefrompng($from);
			break;
			
			default:
				throw new Exception("Image type not supported");
		}
	}

    /**
	* Return the biggest ratio for width or height
	**/
	private function getRatio($width, $height){
		return max($this->srcWidth / $width, $this->srcHeight / $height);
	}
	
	/**
	* Resize an image keeping the ratio
	*
	* @param string $name
	* @param integer $width
	* @param integer $height
	* @param string $type
	* @param string $from
	* @return bool
	*/
	public function niceResize($name, $width, $height, $type = "jpg", $from = "")
	{
		$ratio = $this->getRatio($width, $height);
		$new_width = $this->srcWidth / $ratio;
		$new_height = $this->srcHeight / $ratio;
		
		return $this->hardResize($name, $new_width, $new_height, $type, $from);
	}
	
	/**
	* Resize an image using the ratio old width / new width
	*
	* @param string $name
	* @param integer $width
	* @param string $type
	* @param string $from
	* @return bool
	*/
	public function xResize($name, $width, $type = "jpg", $from = "")
	{
		$ratio = $this->srcWidth / $width;
		$new_width = $this->srcWidth / $ratio;
		$new_height = $this->srcHeight / $ratio;
		
		return $this->hardResize($name, $new_width, $new_height, $type, $from);
	}
	
	/**
	* Resize an image using the ratio old height / new height
	*
	* @param string $name
	* @param integer $height
	* @param string $type
	* @param string $from
	* @return bool
	*/
	public function yResize($name, $height, $type = "jpg", $from = "")
	{
		$ratio = $this->srcHeight / $height;
		$new_width = $this->srcWidth / $ratio;
		$new_height = $this->srcHeight / $ratio;
		
		return $this->hardResize($name, $new_width, $new_height, $type, $from);
	}
	
	/**
	* Function that take a part of an image
	*
	* @param string $name
	* @param integer $coordX
	* @param integer $coordY
	* @param integer $width
	* @param integer $height
	* @param string $type
	* @param string $from
	**/
	public function crop($name, $coordX, $coordY, $width, $height, $type = "jpg", $from = "")
	{
		//On vérifie les coordonnées
		if($coordX + $width > $this->srcWidth)
			throw new Exception("Impossible de croper cette portion, X + longueur > largeur de l'image");
		elseif($coordY + $height > $this->srcHeight)
			throw new Exception("Impossible de croper cette portion, Y + hauteur > hauteur de l'image");			
			
		$this->setNewImage($name);
		$this->setNewWidth($width);
		$this->setNewHeight($height);
		
		if(empty($from))
		{
			if(empty($this->srcImage)) return false;
			$from = $this->srcImage;
		}
		$this->getImageRessource($from);
		
		$thumb = imagecreatetruecolor($this->newWidth, $this->newHeight);
		
		if(!imagecopyresampled($thumb, $this->rscImg, 0, 0, $coordX, $coordY, 
								$this->newWidth, $this->newHeight, $this->newWidth, $this->newWidth))
			throw new Exception("Impossible de redimensionner l'image");
		
		switch($type)
		{
			case 'jpg':
			case 'jpeg':
				return imagejpeg($thumb, $name, 100);
			break;
			
			case 'gif':
				return imagegif($thumb, $name);
			break;
			
			case 'png':
				return imagepng($thumb, $name);
			break;
			
			default:
				throw new Exception("Impossible de créer la nouvelle image le type $type ne convient pas");
		}
	}
}

?>