<?php

/**

 * WordPress API for media display.

 *

 * @package WordPress

 * @subpackage Media

 */

/**

 * Scale down the default size of an image.

 *

 * This is so that the image is a better fit for the editor and theme.

 *

 * The `$size` parameter accepts either an array or a string. The supported string

 * values are 'thumb' or 'thumbnail' for the given thumbnail size or defaults at

 * 128 width and 96 height in pixels. Also supported for the string value is

 * than the supported will result in the content_width size or 500 if that is

 * not set.

 *

 * Finally, there is a filter named {@see 'editor_max_image_size'}, that will be

 * called on the calculated array for width and height, respectively. The second

 * parameter will be the value that was in the $size parameter. The returned

 * type for the hook is an array with the width as the first element and the

 * height as the second element.

 *

 * @since 2.5.0

 *

 * @param int          $width   Width of the image in pixels.

 * @param int          $height  Height of the image in pixels.

 * @param string       $context Optional. Could be 'display' (like in a theme) or 'edit'

 *                              (like inserting into an editor). Default null.

 * @return array Width and height of what the result image should resize to.

 */

function image_constrain_size_for_editor( $width, $height, $size = 'medium', $context = null ) {

	if ( ! $context )

		$context = is_admin() ? 'edit' : 'display';

	if ( is_array($size) ) {

		$max_width = $size[0];

		$max_height = $size[1];

	}

	elseif ( $size == 'thumb' || $size == 'thumbnail' ) {

		$max_width = intval(get_option('thumbnail_size_w'));

		$max_height = intval(get_option('thumbnail_size_h'));

		// last chance thumbnail size defaults

		if ( !$max_width && !$max_height ) {

			$max_width = 128;

			$max_height = 96;

		}

	}

	elseif ( $size == 'medium' ) {

		$max_width = intval(get_option('medium_size_w'));

		$max_height = intval(get_option('medium_size_h'));

	}

	elseif ( $size == 'large' ) {

		/*

		 * We're inserting a large size image into the editor. If it's a really

		 * big image we'll scale it down to fit reasonably within the editor

		 * itself, and within the theme's content width if it's known. The user

		 * can resize it in the editor if they wish.

		 */

		$max_width = intval(get_option('large_size_w'));

		$max_height = intval(get_option('large_size_h'));

			$max_width = min( intval($content_width), $max_width );

		$max_width = intval( $_wp_additional_image_sizes[$size]['width'] );

		$max_height = intval( $_wp_additional_image_sizes[$size]['height'] );

	}

	// $size == 'full' has no constraint

	else {

		$max_width = $width;

		$max_height = $height;

	}

	/**

	 *

	 * @since 2.5.0

	 *

	 * @param array        $max_image_size An array with the width as the first element,

	 *                                     and the height as the second element.

	 * @param string|array $size           Size of what the result image should be.

	 * @param string       $context        The context the image is being resized for.

	 *                                     Possible values are 'display' (like in a theme)

	 *                                     or 'edit' (like inserting into an editor).

	 */

	list( $max_width, $max_height ) = apply_filters( 'editor_max_image_size', array( $max_width, $max_height ), $size, $context );

	return wp_constrain_dimensions( $width, $height, $max_width, $max_height );

}

/**

 * Retrieve width and height attributes using given width and height values.

 *

 * Both attributes are required in the sense that both parameters must have a

 * value, but are optional in that if you set them to false or null, then they

 * will not be added to the returned string.

 *

 * You can set the value using a string, but it will only take numeric values.

 * If you wish to put 'px' after the numbers, then it will be stripped out of

 * the return.

 *

 * @since 2.5.0

 *

 * @param int|string $width  Image width in pixels.

 * @param int|string $height Image height in pixels.

 * @return string HTML attributes for width and, or height.

 */

function image_hwstring( $width, $height ) {

	$out = '';

	if ($width)

		$out .= 'width="'.intval($width).'" ';

	if ($height)

		$out .= 'height="'.intval($height).'" ';

	return $out;

}

/**

 * Scale an image to fit a particular size (such as 'thumb' or 'medium').

 *

 * Array with image url, width, height, and whether is intermediate size, in

 * that order is returned on success is returned. $is_intermediate is true if

 * $url is a resized image, false if it is the original.

 *

 * The URL might be the original image, or it might be a resized version. This

 * function won't create a new resized copy, it will just return an already

 * resized one if it exists.

 *

 * resizing services for images. The hook must return an array with the same

 * elements that are returned in the function. The first element being the URL

 * to the new image that was resized.

 *

 * @since 2.5.0

 *

 * @param int          $id   Attachment ID for image.

 */

function image_downsize( $id, $size = 'medium' ) {

	/**

	 *

	 * Passing a truthy value to the filter will effectively short-circuit

	 * down-sizing the image, returning that value as output instead.

	 *

	 * @since 2.5.0

	 *

	 * @param bool         $downsize Whether to short-circuit the image downsize. Default false.

	 * @param int          $id       Attachment ID for image.

	 */

	if ( $out = apply_filters( 'image_downsize', false, $id, $size ) ) {

		return $out;

	}

	$img_url = wp_get_attachment_url($id);

	$meta = wp_get_attachment_metadata($id);

	$width = $height = 0;

	$is_intermediate = false;

	$img_url_basename = wp_basename($img_url);

	// try for a new style intermediate size

	if ( $intermediate = image_get_intermediate_size($id, $size) ) {

		$img_url = str_replace($img_url_basename, $intermediate['file'], $img_url);

		$width = $intermediate['width'];

		$height = $intermediate['height'];

		$is_intermediate = true;

	}

	elseif ( $size == 'thumbnail' ) {

		// fall back to the old thumbnail

		if ( ($thumb_file = wp_get_attachment_thumb_file($id)) && $info = getimagesize($thumb_file) ) {

			$img_url = str_replace($img_url_basename, wp_basename($thumb_file), $img_url);

			$width = $info[0];

			$height = $info[1];

			$is_intermediate = true;

		}

	}

	if ( !$width && !$height && isset( $meta['width'], $meta['height'] ) ) {

		// any other type: use the real image

		$width = $meta['width'];

		$height = $meta['height'];

	}

	if ( $img_url) {

		// we have the actual image size, but might need to further constrain it if content_width is narrower

		list( $width, $height ) = image_constrain_size_for_editor( $width, $height, $size );

		return array( $img_url, $width, $height, $is_intermediate );

	}

	return false;

}

/**

 * Register a new image size.

 *

 * Cropping behavior for the image size is dependent on the value of $crop:

 * 1. If false (default), images will be scaled, not cropped.

 * 2. If an array in the form of array( x_crop_position, y_crop_position ):

 *    - x_crop_position accepts 'left' 'center', or 'right'.

 *    - y_crop_position accepts 'top', 'center', or 'bottom'.

 *    Images will be cropped to the specified dimensions within the defined crop area.

 * 3. If true, images will be cropped to the specified dimensions using center positions.

 *

 * @since 2.9.0

 *

 * @global array $_wp_additional_image_sizes Associative array of additional image sizes.

 *

 * @param string     $name   Image size identifier.

 * @param int        $width  Image width in pixels.

 * @param int        $height Image height in pixels.

 *                           An array can specify positioning of the crop area. Default false.

 */

function add_image_size( $name, $width = 0, $height = 0, $crop = false ) {

	global $_wp_additional_image_sizes;

	$_wp_additional_image_sizes[ $name ] = array(

		'width'  => absint( $width ),

		'height' => absint( $height ),

		'crop'   => $crop,

	);

}

/**

 * Check if an image size exists.

 *

 * @since 3.9.0

 *

 * @param string $name The image size to check.

 * @return bool True if the image size exists, false if not.

 */

function has_image_size( $name ) {

}

/**

 * Remove a new image size.

 *

 * @since 3.9.0

 *

 * @param string $name The image size to remove.

 * @return bool True if the image size was successfully removed, false on failure.

 */

function remove_image_size( $name ) {

	global $_wp_additional_image_sizes;

	if ( isset( $_wp_additional_image_sizes[ $name ] ) ) {

		unset( $_wp_additional_image_sizes[ $name ] );

		return true;

	}

	return false;

}

/**

 * Registers an image size for the post thumbnail.

 *

 * @since 2.9.0

 *

 * @see add_image_size() for details on cropping behavior.

 *

 * @param int        $width  Image width in pixels.

 * @param int        $height Image height in pixels.

 *                           An array can specify positioning of the crop area. Default false.

 */

function set_post_thumbnail_size( $width = 0, $height = 0, $crop = false ) {

	add_image_size( 'post-thumbnail', $width, $height, $crop );

}

/**

 * Gets an img tag for an image attachment, scaling it down if requested.

 *

 * image without having to use regular expressions on the HTML content. The

 * parameters are: what WordPress will use for the class, the Attachment ID,

 * image align value, and the size the image should be.

 *

 * further manipulated by a plugin to change all attribute values and even HTML

 * content.

 *

 * @since 2.5.0

 *

 * @param int          $id    Attachment ID.

 * @param string       $alt   Image Description for the alt attribute.

 * @param string       $title Image Description for the title attribute.

 * @param string       $align Part of the class name for aligning the image.

 * @return string HTML IMG element for given image attachment

 */

function get_image_tag( $id, $alt, $title, $align, $size = 'medium' ) {

	list( $img_src, $width, $height ) = image_downsize($id, $size);

	$hwstring = image_hwstring($width, $height);

	$title = $title ? 'title="' . esc_attr( $title ) . '" ' : '';

	$class = 'align' . esc_attr($align) .' size-' . esc_attr($size) . ' wp-image-' . $id;

	/**

	 *

	 * @since 2.6.0

	 *

	 */

	$class = apply_filters( 'get_image_tag_class', $class, $id, $align, $size );

	$html = '<img src="' . esc_attr($img_src) . '" alt="' . esc_attr($alt) . '" ' . $title . $hwstring . 'class="' . $class . '" />';

	/**

	 *

	 * @since 2.6.0

	 *

	 */

}

/**

 * Calculates the new dimensions for a down-sampled image.

 *

 * If either width or height are empty, no constraint is applied on

 * that dimension.

 *

 * @since 2.5.0

 *

 * @param int $current_width  Current width of the image.

 * @param int $current_height Current height of the image.

 * @param int $max_width      Optional. Max width in pixels to constrain to. Default 0.

 * @param int $max_height     Optional. Max height in pixels to constrain to. Default 0.

 * @return array First item is the width, the second item is the height.

 */

function wp_constrain_dimensions( $current_width, $current_height, $max_width = 0, $max_height = 0 ) {

	if ( !$max_width && !$max_height )

		return array( $current_width, $current_height );

	$width_ratio = $height_ratio = 1.0;

	$did_width = $did_height = false;

	if ( $max_width > 0 && $current_width > 0 && $current_width > $max_width ) {

		$width_ratio = $max_width / $current_width;

		$did_width = true;

	}

	if ( $max_height > 0 && $current_height > 0 && $current_height > $max_height ) {

		$height_ratio = $max_height / $current_height;

		$did_height = true;

	}

	// Calculate the larger/smaller ratios

	$smaller_ratio = min( $width_ratio, $height_ratio );

	$larger_ratio  = max( $width_ratio, $height_ratio );

	if ( (int) round( $current_width * $larger_ratio ) > $max_width || (int) round( $current_height * $larger_ratio ) > $max_height ) {

 		// The larger ratio is too big. It would result in an overflow.

		$ratio = $smaller_ratio;

	} else {

		// The larger ratio fits, and is likely to be a more "snug" fit.

		$ratio = $larger_ratio;

	}

	// Very small dimensions may result in 0, 1 should be the minimum.

	$w = max ( 1, (int) round( $current_width  * $ratio ) );

	$h = max ( 1, (int) round( $current_height * $ratio ) );

	// Sometimes, due to rounding, we'll end up with a result like this: 465x700 in a 177x177 box is 117x176... a pixel short

	// We also have issues with recursive calls resulting in an ever-changing result. Constraining to the result of a constraint should yield the original result.

	// Thus we look for dimensions that are one pixel shy of the max value and bump them up

	// Note: $did_width means it is possible $smaller_ratio == $width_ratio.

	if ( $did_width && $w == $max_width - 1 ) {

		$w = $max_width; // Round it up

	}

	// Note: $did_height means it is possible $smaller_ratio == $height_ratio.

	if ( $did_height && $h == $max_height - 1 ) {

		$h = $max_height; // Round it up

	}

	/**

	 *

	 * @since 4.1.0

	 *

	 * @param array $dimensions     The image width and height.

	 * @param int 	$current_width  The current width of the image.

	 * @param int 	$current_height The current height of the image.

	 * @param int 	$max_width      The maximum width permitted.

	 * @param int 	$max_height     The maximum height permitted.

	 */

	return apply_filters( 'wp_constrain_dimensions', array( $w, $h ), $current_width, $current_height, $max_width, $max_height );

}

/**

 * Retrieves calculated resize dimensions for use in WP_Image_Editor.

 *

 * Calculates dimensions and coordinates for a resized image that fits

 * within a specified width and height.

 *

 * Cropping behavior is dependent on the value of $crop:

 * 1. If false (default), images will not be cropped.

 * 2. If an array in the form of array( x_crop_position, y_crop_position ):

 *    - x_crop_position accepts 'left' 'center', or 'right'.

 *    - y_crop_position accepts 'top', 'center', or 'bottom'.

 *    Images will be cropped to the specified dimensions within the defined crop area.

 * 3. If true, images will be cropped to the specified dimensions using center positions.

 *

 * @since 2.5.0

 *

 * @param int        $orig_w Original width in pixels.

 * @param int        $orig_h Original height in pixels.

 * @param int        $dest_w New width in pixels.

 * @param int        $dest_h New height in pixels.

 *                           An array can specify positioning of the crop area. Default false.

 */

	if ($orig_w <= 0 || $orig_h <= 0)

		return false;