GetImageSize

<?php

namespace Core\Image;

class Getimagesize {
	private $strpos = 0;
	private $str;
	private $uri;
	private $type;
	private $handle;
	public function __construct($uri = null) {
		if ($uri)
			$this->load ( $uri );
	}
	public function load($uri) {
		if ($this->handle)
			$this->close ();

		$this->uri = $uri;
		$this->handle = @fopen ( $uri, 'r' );
	}
	public function close() {
		if ($this->handle)
			fclose ( $this->handle );
	}
	public function getSize() {
		$this->strpos = 0;
		if ($this->getType ()) {
			return $this->parseSize ();
		}

		return false;
	}
	public function getType() {
		$this->strpos = 0;

		if (! $this->type) {
			switch ($this->getChars ( 2 )) {
				case "BM" :
					return $this->type = 'bmp';
				case "GI" :
					return $this->type = 'gif';
				case chr ( 0xFF ) . chr ( 0xd8 ) :
					return $this->type = 'jpeg';
				case chr ( 0x89 ) . 'P' :
					return $this->type = 'png';
				default :
					return false;
			}
		}

		return $this->type;
	}
	private function parseSize() {
		$this->strpos = 0;
		switch ($this->type) {
			case 'png' :
				$info = $this->parseSizeForPNG ();
				if ($info) {
					$info = array (
							$info [1],
							$info [2],
							3,
							'width="' . $info [1] . '" height="' . $info [2] . '"',
							'bits' => 8,
							'mime' => 'image/png'
					);
				}
				return $info;
			case 'gif' :
				$info = $this->parseSizeForGIF ();
				if ($info) {
					$info = array (
							$info [1],
							$info [2],
							1,
							'width="' . $info [1] . '" height="' . $info [2] . '"',
							'bits' => 8,
							'mime' => 'image/gif'
					);
				}
				return $info;
			case 'bmp' :
				$info = $this->parseSizeForBMP ();
				if ($info) {
					$info = array (
							$info [1],
							$info [2],
							6,
							'width="' . $info [1] . '" height="' . $info [2] . '"',
							'bits' => 8,
							'mime' => 'image/x-ms-bmp'
					);
				}
				return $info;
			case 'jpeg' :
				$info = $this->parseSizeForJPEG ();
				if ($info) {
					$info = array (
							$info [0],
							$info [1],
							2,
							'width="' . $info [0] . '" height="' . $info [1] . '"',
							'bits' => 8,
							'mime' => 'image/jpeg'
					);
				}
				return $info;
		}

		return null;
	}
	private function parseSizeForPNG() {
		$chars = $this->getChars ( 25 );

		return unpack ( "N*", substr ( $chars, 16, 8 ) );
	}
	private function parseSizeForGIF() {
		$chars = $this->getChars ( 11 );

		return unpack ( "S*", substr ( $chars, 6, 4 ) );
	}
	private function parseSizeForBMP() {
		$chars = $this->getChars ( 29 );
		$chars = substr ( $chars, 14, 14 );
		$type = unpack ( 'C', $chars );

		return (reset ( $type ) == 40) ? unpack ( 'L*', substr ( $chars, 4 ) ) : unpack ( 'L*', substr ( $chars, 4, 8 ) );
	}
	private function parseSizeForJPEG() {
		$state = null;
		$i = 0;

		while ( true ) {
			switch ($state) {
				default :
					$this->getChars ( 2 );
					$state = 'started';
					break;

				case 'started' :
					$b = $this->getByte ();
					if ($b === false)
						return false;

					$state = $b == 0xFF ? 'sof' : 'started';
					break;

				case 'sof' :
					$b = $this->getByte ();
					if (in_array ( $b, range ( 0xe0, 0xef ) )) {
						$state = 'skipframe';
					} elseif (in_array ( $b, array_merge ( range ( 0xC0, 0xC3 ), range ( 0xC5, 0xC7 ), range ( 0xC9, 0xCB ), range ( 0xCD, 0xCF ) ) )) {
						$state = 'readsize';
					} elseif ($b == 0xFF) {
						$state = 'sof';
					} else {
						$state = 'skipframe';
					}
					break;

				case 'skipframe' :
					$skip = $this->readInt ( $this->getChars ( 2 ) ) - 2;
					$state = 'doskip';
					break;

				case 'doskip' :
					$this->getChars ( $skip );
					$state = 'started';
					break;

				case 'readsize' :
					$c = $this->getChars ( 7 );

					return array (
							$this->readInt ( substr ( $c, 5, 2 ) ),
							$this->readInt ( substr ( $c, 3, 2 ) )
					);
			}
		}
	}
	private function getChars($n) {
		if (! $this->handle)
			return false;
		$response = null;

		// do we need more data?
		if ($this->strpos + $n - 1 >= strlen ( $this->str )) {
			$end = ($this->strpos + $n);

			while ( strlen ( $this->str ) < $end && $response !== false ) {
				// read more from the file handle
				$need = $end - ftell ( $this->handle );

				if ($response = fread ( $this->handle, $need )) {
					$this->str .= $response;
				} else {
					return false;
				}
			}
		}

		$result = substr ( $this->str, $this->strpos, $n );
		$this->strpos += $n;

		// we are dealing with bytes here, so force the encoding
		return mb_convert_encoding ( $result, "8BIT" );
	}
	private function getByte() {
		$c = $this->getChars ( 1 );
		$b = unpack ( "C", $c );

		return reset ( $b );
	}
	private function readInt($str) {
		$size = unpack ( "C*", $str );

		return ($size [1] << 8) + $size [2];
	}
	public function __destruct() {
		$this->close ();
	}
}