<?php

/**

 * File contains all the administration image manipulation functions.

 *

 * @package WordPress

 * @subpackage Administration

 */

/**

 * Create a thumbnail from an Image given a maximum side size.

 *

 * This function can handle most image file formats which PHP supports. If PHP

 * does not have the functionality to save in a file of the same format, the

 * thumbnail will be created as a jpeg.

 *

 * @since 1.2.0

 *

 * @param mixed $file Filename of the original image, Or attachment id.

 * @param int $max_side Maximum length of a single side for the thumbnail.

 * @return string Thumbnail path on success, Error string on failure.

 */

function wp_create_thumbnail( $file, $max_side, $deprecated = '' ) {

	$thumbpath = image_resize( $file, $max_side, $max_side );

	return apply_filters( 'wp_create_thumbnail', $thumbpath );

}

/**

 * Crop an Image to a given size.

 *

 * @since 2.1.0

 *

 * @param string|int $src_file The source file or Attachment ID.

 * @param int $src_x The start x position to crop from.

 * @param int $src_y The start y position to crop from.

 * @param int $src_w The width to crop.

 * @param int $src_h The height to crop.

 * @param int $dst_w The destination width.

 * @param int $dst_h The destination height.

 * @param int $src_abs Optional. If the source crop points are absolute.

 * @param string $dst_file Optional. The destination file to write to.

 * @return string New filepath on success, String error message on failure.

 */

function wp_crop_image( $src_file, $src_x, $src_y, $src_w, $src_h, $dst_w, $dst_h, $src_abs = false, $dst_file = false ) {

	if ( is_numeric( $src_file ) ) // Handle int as attachment ID

		$src_file = get_attached_file( $src_file );

	$src = wp_load_image( $src_file );

	if ( !is_resource( $src ))

		return $src;

	$dst = wp_imagecreatetruecolor( $dst_w, $dst_h );

	if ( $src_abs ) {

		$src_w -= $src_x;

		$src_h -= $src_y;

	}

	if (function_exists('imageantialias'))

		imageantialias( $dst, true );

	imagecopyresampled( $dst, $src, 0, 0, $src_x, $src_y, $dst_w, $dst_h, $src_w, $src_h );

	imagedestroy( $src ); // Free up memory

	if ( ! $dst_file )

		$dst_file = str_replace( basename( $src_file ), 'cropped-' . basename( $src_file ), $src_file );

	$dst_file = preg_replace( '/\\.[^\\.]+$/', '.jpg', $dst_file );

	if ( imagejpeg( $dst, $dst_file, apply_filters( 'jpeg_quality', 90, 'wp_crop_image' ) ) )

		return $dst_file;

	else

		return false;

}

/**

 * Generate post thumbnail attachment meta data.

 *

 * @since 2.1.0

 *

 * @param int $attachment_id Attachment Id to process.

 * @param string $file Filepath of the Attached image.

 * @return mixed Metadata for attachment.

 */

function wp_generate_attachment_metadata( $attachment_id, $file ) {

	$attachment = get_post( $attachment_id );

	$metadata = array();

	if ( preg_match('!^image/!', get_post_mime_type( $attachment )) && file_is_displayable_image($file) ) {

		$imagesize = getimagesize( $file );

		$metadata['width'] = $imagesize[0];

		$metadata['height'] = $imagesize[1];

		list($uwidth, $uheight) = wp_shrink_dimensions($metadata['width'], $metadata['height']);

		$metadata['hwstring_small'] = "height='$uheight' width='$uwidth'";

		// Make the file path relative to the upload dir

		$metadata['file'] = _wp_relative_upload_path($file);

		// make thumbnails and other intermediate sizes

		global $_wp_additional_image_sizes;

		$temp_sizes = array('thumbnail', 'medium', 'large'); // Standard sizes

		if ( isset( $_wp_additional_image_sizes ) && count( $_wp_additional_image_sizes ) )

			$temp_sizes = array_merge( $temp_sizes, array_keys( $_wp_additional_image_sizes ) );

		$temp_sizes = apply_filters( 'intermediate_image_sizes', $temp_sizes );

		foreach ( $temp_sizes as $s ) {

			$sizes[$s] = array( 'width' => '', 'height' => '', 'crop' => FALSE );

			if ( isset( $_wp_additional_image_sizes[$s]['width'] ) )

				$sizes[$s]['width'] = intval( $_wp_additional_image_sizes[$s]['width'] ); // For theme-added sizes

			else

				$sizes[$s]['width'] = get_option( "{$s}_size_w" ); // For default sizes set in options

			if ( isset( $_wp_additional_image_sizes[$s]['height'] ) )

				$sizes[$s]['height'] = intval( $_wp_additional_image_sizes[$s]['height'] ); // For theme-added sizes

			else

				$sizes[$s]['height'] = get_option( "{$s}_size_h" ); // For default sizes set in options

			if ( isset( $_wp_additional_image_sizes[$s]['crop'] ) )

				$sizes[$s]['crop'] = intval( $_wp_additional_image_sizes[$s]['crop'] ); // For theme-added sizes

			else

				$sizes[$s]['crop'] = get_option( "{$s}_crop" ); // For default sizes set in options

		}

		$sizes = apply_filters( 'intermediate_image_sizes_advanced', $sizes );

		foreach ($sizes as $size => $size_data ) {

			$resized = image_make_intermediate_size( $file, $size_data['width'], $size_data['height'], $size_data['crop'] );

			if ( $resized )

				$metadata['sizes'][$size] = $resized;

		}

		// fetch additional metadata from exif/iptc

		$image_meta = wp_read_image_metadata( $file );

		if ( $image_meta )

			$metadata['image_meta'] = $image_meta;

	}

	return apply_filters( 'wp_generate_attachment_metadata', $metadata, $attachment_id );

}

/**

 * Load an image from a string, if PHP supports it.

 *

 * @since 2.1.0

 *

 * @param string $file Filename of the image to load.

 * @return resource The resulting image resource on success, Error string on failure.

 */

function wp_load_image( $file ) {

	if ( is_numeric( $file ) )

		$file = get_attached_file( $file );

	if ( ! file_exists( $file ) )

		return sprintf(__('File “%s” doesn’t exist?'), $file);

	if ( ! function_exists('imagecreatefromstring') )

		return __('The GD image library is not installed.');

	// Set artificially high because GD uses uncompressed images in memory

	@ini_set('memory_limit', '256M');

	$image = imagecreatefromstring( file_get_contents( $file ) );

	if ( !is_resource( $image ) )

		return sprintf(__('File “%s” is not an image.'), $file);

	return $image;

}

/**

 * Calculated the new dimentions for a downsampled image.

 *

 * @since 2.0.0

 * @see wp_shrink_dimensions()

 *

 * @param int $width Current width of the image

 * @param int $height Current height of the image

 * @return mixed Array(height,width) of shrunk dimensions.

 */

function get_udims( $width, $height) {

	return wp_shrink_dimensions( $width, $height );

}

/**

 * Calculates the new dimentions for a downsampled image.

 *

 * @since 2.0.0

 * @see wp_constrain_dimensions()

 *

 * @param int $width Current width of the image

 * @param int $height Current height of the image

 * @param int $wmax Maximum wanted width

 * @param int $hmax Maximum wanted height

 * @return mixed Array(height,width) of shrunk dimensions.

 */

function wp_shrink_dimensions( $width, $height, $wmax = 128, $hmax = 96 ) {

	return wp_constrain_dimensions( $width, $height, $wmax, $hmax );

}

/**

 * Convert a fraction string to a decimal.

 *

 * @since 2.5.0

 *

 * @param string $str

 * @return int|float

 */

function wp_exif_frac2dec($str) {

	@list( $n, $d ) = explode( '/', $str );

	if ( !empty($d) )

		return $n / $d;

	return $str;

}

/**

 * Convert the exif date format to a unix timestamp.

 *

 * @since 2.5.0

 *

 * @param string $str

 * @return int

 */

function wp_exif_date2ts($str) {

	@list( $date, $time ) = explode( ' ', trim($str) );

	@list( $y, $m, $d ) = explode( ':', $date );

	return strtotime( "{$y}-{$m}-{$d} {$time}" );

}

/**

 * Get extended image metadata, exif or iptc as available.

 *

 * Retrieves the EXIF metadata aperture, credit, camera, caption, copyright, iso

 * created_timestamp, focal_length, shutter_speed, and title.

 *

 * The IPTC metadata that is retrieved is APP13, credit, byline, created date

 * and time, caption, copyright, and title. Also includes FNumber, Model,

 * DateTimeDigitized, FocalLength, ISOSpeedRatings, and ExposureTime.

 *

 * @todo Try other exif libraries if available.

 * @since 2.5.0

 *

 * @param string $file

 * @return bool|array False on failure. Image metadata array on success.

 */

function wp_read_image_metadata( $file ) {

	if ( !file_exists( $file ) )

		return false;

	list(,,$sourceImageType) = getimagesize( $file );

	// exif contains a bunch of data we'll probably never need formatted in ways

	// that are difficult to use. We'll normalize it and just extract the fields

	// that are likely to be useful.  Fractions and numbers are converted to

	// floats, dates to unix timestamps, and everything else to strings.

	$meta = array(

		'aperture' => 0,

		'credit' => '',

		'camera' => '',

		'caption' => '',

		'created_timestamp' => 0,

		'copyright' => '',

		'focal_length' => 0,

		'iso' => 0,

		'shutter_speed' => 0,

		'title' => '',

	);

	// read iptc first, since it might contain data not available in exif such

	// as caption, description etc

	if ( is_callable('iptcparse') ) {

		getimagesize($file, $info);

		if ( !empty($info['APP13']) ) {

			$iptc = iptcparse($info['APP13']);

			if ( !empty($iptc['2#110'][0]) ) // credit

				$meta['credit'] = utf8_encode(trim($iptc['2#110'][0]));

			elseif ( !empty($iptc['2#080'][0]) ) // byline

				$meta['credit'] = utf8_encode(trim($iptc['2#080'][0]));

			if ( !empty($iptc['2#055'][0]) and !empty($iptc['2#060'][0]) ) // created date and time

				$meta['created_timestamp'] = strtotime($iptc['2#055'][0] . ' ' . $iptc['2#060'][0]);

			if ( !empty($iptc['2#120'][0]) ) // caption

				$meta['caption'] = utf8_encode(trim($iptc['2#120'][0]));

			if ( !empty($iptc['2#116'][0]) ) // copyright

				$meta['copyright'] = utf8_encode(trim($iptc['2#116'][0]));

			if ( !empty($iptc['2#005'][0]) ) // title

				$meta['title'] = utf8_encode(trim($iptc['2#005'][0]));

		 }

	}

	// fetch additional info from exif if available

	if ( is_callable('exif_read_data') && in_array($sourceImageType, apply_filters('wp_read_image_metadata_types', array(IMAGETYPE_JPEG, IMAGETYPE_TIFF_II, IMAGETYPE_TIFF_MM)) ) ) {

		$exif = @exif_read_data( $file );

		if (!empty($exif['FNumber']))

			$meta['aperture'] = round( wp_exif_frac2dec( $exif['FNumber'] ), 2 );

		if (!empty($exif['Model']))

			$meta['camera'] = trim( $exif['Model'] );

		if (!empty($exif['DateTimeDigitized']))

			$meta['created_timestamp'] = wp_exif_date2ts($exif['DateTimeDigitized']);

		if (!empty($exif['FocalLength']))

			$meta['focal_length'] = wp_exif_frac2dec( $exif['FocalLength'] );

		if (!empty($exif['ISOSpeedRatings']))

			$meta['iso'] = $exif['ISOSpeedRatings'];

		if (!empty($exif['ExposureTime']))

			$meta['shutter_speed'] = wp_exif_frac2dec( $exif['ExposureTime'] );

	}

	return apply_filters( 'wp_read_image_metadata', $meta, $file, $sourceImageType );

}

/**

 * Validate that file is an image.

 *

 * @since 2.5.0

 *

 * @param string $path File path to test if valid image.

 * @return bool True if valid image, false if not valid image.

 */

function file_is_valid_image($path) {

	$size = @getimagesize($path);

	return !empty($size);

}

/**

 * Validate that file is suitable for displaying within a web page.

 *

 * @since 2.5.0

 * @uses apply_filters() Calls 'file_is_displayable_image' on $result and $path.

 *

 * @param string $path File path to test.

 * @return bool True if suitable, false if not suitable.

 */

function file_is_displayable_image($path) {

	$info = @getimagesize($path);

	if ( empty($info) )

		$result = false;

	elseif ( !in_array($info[2], array(IMAGETYPE_GIF, IMAGETYPE_JPEG, IMAGETYPE_PNG)) )	// only gif, jpeg and png images can reliably be displayed

		$result = false;

	else

		$result = true;

	return apply_filters('file_is_displayable_image', $result, $path);

}