<?php
/**
 * This class is used to create an image collage from
 * an array of image links.
 *
 * @author Tully Rankin
 * @website http://www.TullyRankin.com
 */
class Collage {

	/**
	 * Holds array of image links
	 */
	public $images = array();

	/**
	 * Height of the collage image
	 */	
	public $height;

	/**
	 * Width of the collage image
	 */
	public $width;

	/**
	 * Holds the buffer of all images
	 */
	public $imgBuf = array();

	/**
	 * Stores the created collage image
	 */
	public $imgOut;

	/**
	 * Holds array of Exception objects
	 */
	public $errors = array();

	public function __construct(Array $images, $height=1024, $width=768)
	{
		try {
		
			if (empty($images))
				throw new Exception('Images can not be empty.');

			$this->images = $images;
			$this->height = $height;
			$this->width = $width;

			$iTmp = "";

			$this->_addImagesToBuffer();
			$this->imgOut = imagecreatetruecolor($this->width, $this->height);
		} catch (Exception $e) {
			$this->errors[] = $e;
		}
	}

	/**
	 * Creates the collage
	 */
	public function execute()
	{
		$tmpHeight = 0;
		$tmpWidth = 0;

		try {
			do {
				foreach($this->imgBuf as $image) {
					if ($tmpWidth <= $this->width) { 
						@imagecopy($this->imgOut, $image, $tmpWidth, $tmpHeight, 0, 0, imagesx($image), imagesy($image));
						@imagedestroy($image);
						$tmpWidth += 50;
					} else {
						$tmpWidth = 0;
						@imagecopy($this->imgOut, $image, $tmpWidth, $tmpHeight, 0, 0, imagesx($image), imagesy($image));
						@imagedestroy($image);
						$tmpWidth += 50;
						$tmpHeight += 50;
					}
				}
				$this->_addImagesToBuffer();;
			} while($tmpHeight <= $this->height);
		} catch (Exception $e) {
			$this->errors[] = $e;
		}
	}

	/**
	 * Saves the image to a file
	 *
	 * @param string $name The name of the image.
	 * @param string $type The image type to save as.
	 */
	public function saveFile($name, $type="jpeg")
	{
		try {
			ob_start();
			switch($type) {
				case "png":
					@imagepng($this->imgOut);
					break;
				case "jpg":
				case "jpeg":
					@imagejpeg($this->imgOut);
					break;
				case "gif":
					@imagegif($this->imgOut);
					break;
				default:
					throw new Exception("Unknown image type");
			}
			$contents = ob_get_contents();
			ob_end_clean();
			file_put_contents($name, $contents);
		} catch (Exception $e) {
			$this->errors[] = $e;
		}
	}

	/*
	 * Creates an image from each image given in the constructor.
	 * Adds it to public imgBuf array
	 */
	protected function _addImagesToBuffer()
	{
		$this->imgBuf = array();
		foreach($this->images as $imageSrc) {
        	$iTmp = imagecreatefromjpeg($imageSrc);
            array_push($this->imgBuf, $iTmp);
        }

	}
}