<?php
/**
 *----------------------------------------------------------------------------
 * iC Library   Library by JoomliC, for Joomla!
 *----------------------------------------------------------------------------
 * @version     2.0.0 2021-09-27
 *
 * @package     iC Library
 * @subpackage  Thumb
 * @link        https://www.joomlic.com
 *
 * @author      Cyril Reze
 * @copyright   (c) 2013-2026 Cyril Reze / JoomliC. All rights reserved.
 * @license     GNU General Public License version 3 or later; see LICENSE.txt
 *
 * @since       1.0.0
 *----------------------------------------------------------------------------
*/

namespace iClib\Thumb;

\defined('_JEXEC') or die;

/**
 * iC Library iCThumbImage class
 */
class Image
{
	/**
	 * Create image from a BMP
	 */
	public static function createFromBMP($filename)
	{
		// Open file in binary mode
		if (! $f1 = fopen($filename,"rb")) return FALSE;

		//1 : Loads file header
		$FILE = unpack("vfile_type/Vfile_size/Vreserved/Vbitmap_offset", fread($f1,14));
		if ($FILE['file_type'] != 19778) return FALSE;

		//2 : Loads BMP header
		$BMP = unpack('Vheader_size/Vwidth/Vheight/vplanes/vbits_per_pixel'.
					'/Vcompression/Vsize_bitmap/Vhoriz_resolution'.
					'/Vvert_resolution/Vcolors_used/Vcolors_important', fread($f1,40));
		$BMP['colors'] = pow(2,$BMP['bits_per_pixel']);
		if ($BMP['size_bitmap'] == 0) $BMP['size_bitmap'] = $FILE['file_size'] - $FILE['bitmap_offset'];
		$BMP['bytes_per_pixel'] = $BMP['bits_per_pixel']/8;
		$BMP['bytes_per_pixel2'] = ceil($BMP['bytes_per_pixel']);
		$BMP['decal'] = ($BMP['width']*$BMP['bytes_per_pixel']/4);
		$BMP['decal'] -= floor($BMP['width']*$BMP['bytes_per_pixel']/4);
		$BMP['decal'] = 4-(4*$BMP['decal']);
		if ($BMP['decal'] == 4) $BMP['decal'] = 0;

		//3 : Loads colors of the palette
		$PALETTE = array();
		if ($BMP['colors'] < 16777216 && $BMP['colors'] != 65536)
		{
			$PALETTE = unpack('V'.$BMP['colors'], fread($f1,$BMP['colors']*4));
		}

		//4 : Creates image
		$IMG = fread($f1,$BMP['size_bitmap']);
		$VIDE = chr(0);

		$res = imagecreatetruecolor($BMP['width'],$BMP['height']);
		$P = 0;
		$Y = $BMP['height']-1;

		while ($Y >= 0)
		{
			$X=0;
			while ($X < $BMP['width'])
			{
				if ($BMP['bits_per_pixel'] == 24)
				{
					$COLOR = unpack("V",substr($IMG,$P,3).$VIDE);
				}
				elseif ($BMP['bits_per_pixel'] == 16)
				{
					$COLOR = unpack("v",substr($IMG,$P,2));
					$blue  = ($COLOR[1] & 0x001f) << 3;
					$green = ($COLOR[1] & 0x07e0) >> 3;
					$red   = ($COLOR[1] & 0xf800) >> 8;
					$COLOR[1] = $red * 65536 + $green * 256 + $blue;
				}
				elseif ($BMP['bits_per_pixel'] == 8)
				{
					$COLOR = unpack("n",$VIDE.substr($IMG,$P,1));
					$COLOR[1] = $PALETTE[$COLOR[1]+1];
				}
				elseif ($BMP['bits_per_pixel'] == 4)
				{
					$COLOR = unpack("n",$VIDE.substr($IMG,floor($P),1));
					if (($P*2)%2 == 0) $COLOR[1] = ($COLOR[1] >> 4) ; else $COLOR[1] = ($COLOR[1] & 0x0F);
					$COLOR[1] = $PALETTE[$COLOR[1]+1];
				}
				elseif ($BMP['bits_per_pixel'] == 1)
				{
					$COLOR = unpack("n",$VIDE.substr($IMG,floor($P),1));
					if     (($P*8)%8 == 0) $COLOR[1] =  $COLOR[1]        >>7;
					elseif (($P*8)%8 == 1) $COLOR[1] = ($COLOR[1] & 0x40)>>6;
					elseif (($P*8)%8 == 2) $COLOR[1] = ($COLOR[1] & 0x20)>>5;
					elseif (($P*8)%8 == 3) $COLOR[1] = ($COLOR[1] & 0x10)>>4;
					elseif (($P*8)%8 == 4) $COLOR[1] = ($COLOR[1] & 0x8)>>3;
					elseif (($P*8)%8 == 5) $COLOR[1] = ($COLOR[1] & 0x4)>>2;
					elseif (($P*8)%8 == 6) $COLOR[1] = ($COLOR[1] & 0x2)>>1;
					elseif (($P*8)%8 == 7) $COLOR[1] = ($COLOR[1] & 0x1);
					$COLOR[1] = $PALETTE[$COLOR[1]+1];
				}
				else
				return FALSE;
				imagesetpixel($res,$X,$Y,$COLOR[1]);
				$X++;
				$P += $BMP['bytes_per_pixel'];
			}
			$Y--;
			$P+=$BMP['decal'];
		}

		// Close file
		fclose($f1);

		return $res;
	}
}