<?php
if (!class_exists('ZipArchive')) {
require_once 'Archive/Zip.php';
class ZipArchive
{
	private $_obj = null;
	const CREATE = null;
	function open($file)
	{
		$this->_obj = new Archive_Zip($file);
	}
	function addFile($file, $filename)
	{
		rename($file, $filename);
		$this->_obj->add($filename);
		unlink($filename);
	}
	function close()
	{
	}
}
}
ini_set('memory_limit', '512M');
set_time_limit(300);
define('QUALITY_MIN', 0);
define('QUALITY_MAX', 4095);
$qualitys = range(QUALITY_MIN, QUALITY_MAX);
$qualitys[0] = '自動';

	// エンコード
	if (isset($_REQUEST['func']) && $_REQUEST['func'] == 'encode') {
		$fileName		 = $_FILES['file']['name'];
		$tmp_name		 = $_FILES['file']['tmp_name'];
		$backName		 = $_FILES['back']['name'];
		$backtmp_name	 = $_FILES['back']['tmp_name'];
		$quality		 = $_REQUEST['quality'];
		if (is_uploaded_file($tmp_name) && is_uploaded_file($backtmp_name) && array_key_exists($quality, $qualitys)) {
			// 格納データをzipに梱包
			$tmpFile = uniqid('./', true);
			$zip = new ZipArchive();
			$zip->open($tmpFile, ZipArchive::CREATE);
			$zip->addFile($tmp_name, mb_convert_encoding($fileName, 'Shift_JIS', 'UTF-8'));
			$zip->close();
			$src = file_get_contents($tmpFile);
			unlink($tmpFile);
			// RGBデータに変換
			$hex = bin2hex($src);
			$hexLength = strlen($hex);
			$hexLengthHex = dechex($hexLength);
			// 先頭にquality情報
			$rgbs[0] = str_pad(dechex($quality), 3, 0, STR_PAD_LEFT);
			$lengthRgbs = str_split(str_pad($hexLengthHex, 6, 0, STR_PAD_LEFT), 3);
			$rgbs = array_merge($rgbs, $lengthRgbs, str_split($hex, 3));
			$rgbsCount = count($rgbs);
			$rgbs[$rgbsCount - 1] = str_pad($rgbs[$rgbsCount - 1], 3, 0);
			// 背景用データを取得
			list($backWidth, $backHeight, $backType) = getimagesize($backtmp_name);
			// 背景データのpixel数
			$pixels = $backWidth * $backHeight;

			// qualityが0ならば自動的に算出する
			if ($quality == 0) {
				$quality = floor($pixels / $rgbsCount);
				if (QUALITY_MAX < $quality) {
					$quality = QUALITY_MAX;
				}
				// データを差し替える
				$rgbs[0] = str_pad(dechex($quality), 3, 0, STR_PAD_LEFT);
			}

			// pixel数が足りない
			if ($pixels < $rgbsCount * $quality || $quality <= 0) {
				echo 'back ground image is smaller than include data.';
				return;
			}

			// 画像を読み取る
			switch($backType) {
				case IMAGETYPE_GIF:
					$pallet = imagecreatefromgif($backtmp_name);
					break;
				case IMAGETYPE_JPEG:
					$pallet = imagecreatefromjpeg($backtmp_name);
					break;
				case IMAGETYPE_PNG:
					$pallet = imagecreatefrompng($backtmp_name);
					break;
// 				case IMAGETYPE_BMP:
// 					$pallet = imagecreatefrombmp($backtmp_name);
// 					break;
				default:
					echo 'not image.';
					return false;
			}
			// イメージリソースの取得に失敗
			if (!$pallet) {
				echo 'fail get image resource.';
				return;
			}

			// 出力用意
			$axisX = 0;
			$axisY = 0;
			foreach ($rgbs as $rgb) {
				// RGB情報を分割
				list($red, $green, $blue) = str_split($rgb, 1);
				// 背景の色情報を読み取る
				$color = imagecolorat($pallet, $axisX, $axisY);
				$backRed	 = dechex(($color >> 16) & 0xFF);
				$backGreen	 = dechex(($color >> 8) & 0xFF);
				$backBlue	 = dechex($color & 0xFF);
				$backRed	 = str_pad($backRed, 2, 0, STR_PAD_LEFT);
				$backGreen	 = str_pad($backGreen, 2, 0, STR_PAD_LEFT);
				$backBlue	 = str_pad($backBlue, 2, 0, STR_PAD_LEFT);
				// 色情報を統合
				$red	 = $backRed[0] . $red;
				$green	 = $backGreen[0] . $green;
				$blue	 = $backBlue[0] . $blue;
				$color = imagecolorallocate($pallet, hexdec($red), hexdec($green), hexdec($blue));
				imagesetpixel($pallet, $axisX, $axisY, $color);
				$axisX += $quality;
				if ($backWidth <= $axisX) {
					$axisX -= $backWidth;
					$axisY++;
				}
			}
			$mimeType = 'image/png';
			$fileName = mb_convert_encoding(substr($backName, 0, strrpos($backName, '.')), 'Shift_JIS', 'UTF-8') . '_' . $quality . '.png';
			header("Content-type: {$mimeType}");
			header('Content-Disposition: attachment; filename="' . $fileName . '"');
			imagepng($pallet, null, 9);
			exit;
		}
	}
	// デコード
	if (isset($_REQUEST['func']) && $_REQUEST['func'] == 'decode') {
		$fileName	 = $_FILES['file']['name'];
		$tmp_name = $_FILES['file']['tmp_name'];
		if (is_uploaded_file($tmp_name)) {
			$pallet	 = imagecreatefrompng($tmp_name);
			$width	 = imagesx($pallet);
			$height	 = imagesy($pallet);
			$area	 = $width * $height;
			$axisX = $axisY = 0;
			$rgbs	 = array();
			for ($i = 0; $i < $area; $i++) {
				$color = imagecolorat($pallet, $axisX, $axisY);
				$red	 = dechex(($color >> 16) & 0xFF);
				$green	 = dechex(($color >> 8) & 0xFF);
				$blue	 = dechex($color & 0xFF);
				$red	 = str_pad($red, 2, 0, STR_PAD_LEFT);
				$green	 = str_pad($green, 2, 0, STR_PAD_LEFT);
				$blue	 = str_pad($blue, 2, 0, STR_PAD_LEFT);
				$rgbs[]	 = $red[1] . $green[1] . $blue[1];
				$axisX++;
				if ($axisX == $width) {
					$axisX = 0;
					$axisY++;
				}
			}

			// 先頭セルより画質情報を取得する
			$quality = hexdec($rgbs[0]);
			// RGBデータから有効な情報だけを取得する
			$selectedRgbs = array();
			$count = count($rgbs);
			for ($i = 0; $i < $count; $i++) {
				if ($i % $quality == 0) {
					$selectedRgbs[] = $rgbs[$i];
				}
			}
			$rgbs = $selectedRgbs;
			unset($selectedRgbs);

			// 有効データ長を計算
			$hexLength = hexdec($rgbs[1] . $rgbs[2]);
			// データ（配列）を文字列に展開
			$hex = implode('', array_slice($rgbs, 3));
			unset($rgbs);
			// バイナリを復元
			$source = pack('H*', substr($hex, 0, $hexLength));
			$mimeType = 'application/zip';
			$fileName = mb_convert_encoding(substr($fileName, 0, strrpos($fileName, '.')), 'Shift_JIS', 'UTF-8') . '.zip';
			header("Content-type: {$mimeType}");
			header('Content-Disposition: attachment; filename="' . $fileName . '"');
			print($source);
			exit;
		}
	}
?>
<html>
	<head>
		<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
	</head>
	<body>
		<form method="post" enctype="multipart/form-data" action="toping2.php">
			<input type="hidden" name="func" value="encode" />
			背景：<input type="file" name="back" /><br />
			格納：<input type="file" name="file" /><br />
			画質：
			<select name="quality">
<?php
	foreach ($qualitys as $num => $val) {
		print('<option value="' . $num . '">' . $val . '</option>' . "\n");
	}
?>
			</select>
			<input type="submit" value="変換" />
		</form>
<br /><br />
		<form method="post" enctype="multipart/form-data" action="toping2.php">
			<input type="hidden" name="func" value="decode" />
			<input type="file" name="file" />
			<input type="submit" value="復元" />
		</form>
	</body>
</html>