<?php
/**
 * Image Resizer class.
 *
 * @package RT_Portfolio
 */

// Do not allow directly accessing this file.
if ( ! defined( 'ABSPATH' ) ) {
	exit( 'This script cannot be accessed directly.' );
}

if ( ! class_exists( 'PFProReSizer' ) ) {
	/**
	 * Image Resizer class.
	 */
	class PFProException extends Exception {
	}

	class PFProReSizer {
		/**
		 * The singleton instance
		 */
		private static $instance = null;

		/**
		 * Should an PFProException be thrown on error?
		 * If false (default), then the error will just be logged.
		 */
		public $throwOnError = false;

		/**
		 * No cloning allowed
		 */
		private function __clone() {
		}

		/**
		 * For your custom default usage you may want to initialize an rtTPGReSizer object by yourself and then have own defaults
		 */
		public static function getInstance() {
			if ( self::$instance == null ) {
				self::$instance = new self();
			}

			return self::$instance;
		}

		/**
		 * Run, forest.
		 */
		public function process( $url, $width = null, $height = null, $crop = null, $single = true, $upscale = false ) {
			try {
				// Validate inputs.
				if ( ! $url ) {
					throw new PFProException( '$url parameter is required' );
				}
				if ( ! $width ) {
					throw new PFProException( '$width parameter is required' );
				}
				if ( ! $height ) {
					throw new PFProException( '$height parameter is required' );
				}

				// Caipt'n, ready to hook.
				if ( true === $upscale ) {
					add_filter( 'image_resize_dimensions', [ $this, 'aq_upscale' ], 10, 6 );
				}

				// Define upload path & dir.
				$upload_info = wp_upload_dir();
				$upload_dir  = $upload_info['basedir'];
				$upload_url  = $upload_info['baseurl'];

				$http_prefix     = 'http://';
				$https_prefix    = 'https://';
				$relative_prefix = '//'; // The protocol-relative URL

				/*
				 if the $url scheme differs from $upload_url scheme, make them match
				   if the schemes differe, images don't show up. */
				if ( ! strncmp( $url, $https_prefix, strlen( $https_prefix ) ) ) { // if url begins with https:// make $upload_url begin with https:// as well
					$upload_url = str_replace( $http_prefix, $https_prefix, $upload_url );
				} elseif ( ! strncmp( $url, $http_prefix, strlen( $http_prefix ) ) ) { // if url begins with http:// make $upload_url begin with http:// as well
					$upload_url = str_replace( $https_prefix, $http_prefix, $upload_url );
				} elseif ( ! strncmp( $url, $relative_prefix, strlen( $relative_prefix ) ) ) { // if url begins with // make $upload_url begin with // as well
					$upload_url = str_replace(
						[
							0 => "$http_prefix",
							1 => "$https_prefix",
						],
						$relative_prefix,
						$upload_url
					);
				}

				// Check if $img_url is local.
				if ( false === strpos( $url, $upload_url ) ) {
					throw new PFProException( 'Image must be local: ' . $url );
				}

				// Define path of image.
				$rel_path = str_replace( $upload_url, '', $url );
				$img_path = $upload_dir . $rel_path;

				// Check if img path exists, and is an image indeed.
				if ( ! file_exists( $img_path ) or ! getimagesize( $img_path ) ) {
					throw new PFProException( 'Image file does not exist (or is not an image): ' . $img_path );
				}

				// Get image info.
				$info                    = pathinfo( $img_path );
				$ext                     = $info['extension'];
				list( $orig_w, $orig_h ) = getimagesize( $img_path );

				// Get image size after cropping.
				$dims = image_resize_dimensions( $orig_w, $orig_h, $width, $height, $crop );
				if ( empty( $dims ) ) {
					return;
				}
				$dst_w = $dims[4];
				$dst_h = $dims[5];

				// Return the original image only if it exactly fits the needed measures.
				if ( ! $dims && ( ( ( null === $height && $orig_w == $width ) xor ( null === $width && $orig_h == $height ) ) xor ( $height == $orig_h && $width == $orig_w ) ) ) {
					$img_url = $url;
					$dst_w   = $orig_w;
					$dst_h   = $orig_h;
				} else {
					// Use this to check if cropped image already exists, so we can return that instead.
					$suffix       = "{$dst_w}x{$dst_h}";
					$dst_rel_path = str_replace( '.' . $ext, '', $rel_path );
					$destfilename = "{$upload_dir}{$dst_rel_path}-{$suffix}.{$ext}";

					if ( ! $dims || ( true == $crop && false == $upscale && ( $dst_w < $width || $dst_h < $height ) ) ) {
						// Can't resize, so return false saying that the action to do could not be processed as planned.
						throw new PFProException( 'Unable to resize image because image_resize_dimensions() failed' );
					} // Else check if cache exists.
					elseif ( file_exists( $destfilename ) && getimagesize( $destfilename ) ) {
						$img_url = "{$upload_url}{$dst_rel_path}-{$suffix}.{$ext}";
					} // Else, we resize the image and return the new resized image url.
					else {

						$editor = wp_get_image_editor( $img_path );

						if ( is_wp_error( $editor ) || is_wp_error( $editor->resize( $width, $height, $crop ) ) ) {
							throw new PFProException(
								'Unable to get WP_Image_Editor: ' .
													  $editor->get_error_message() . ' (is GD or ImageMagick installed?)'
							);
						}

						$resized_file = $editor->save();

						if ( ! is_wp_error( $resized_file ) ) {
							$resized_rel_path = str_replace( $upload_dir, '', $resized_file['path'] );
							$img_url          = $upload_url . $resized_rel_path;
						} else {
							throw new PFProException( 'Unable to save resized image file: ' . $editor->get_error_message() );
						}
					}
				}

				// Okay, leave the ship.
				if ( true === $upscale ) {
					remove_filter( 'image_resize_dimensions', [ $this, 'aq_upscale' ] );
				}

				// Return the output.
				if ( $single ) {
					// str return.
					$image = $img_url;
				} else {
					// array return.
					$image = [
						0 => $img_url,
						1 => $dst_w,
						2 => $dst_h,
					];
				}

				return $image;
			} catch ( PFProException $ex ) {
				error_log( 'rtTPGReSizer.process() error: ' . $ex->getMessage() );

				if ( $this->throwOnError ) {
					// Bubble up exception.
					throw $ex;
				} else {
					// Return false, so that this patch is backwards-compatible.
					return false;
				}
			}
		}

		/**
		 * Callback to overwrite WP computing of thumbnail measures
		 */
		function aq_upscale( $default, $orig_w, $orig_h, $dest_w, $dest_h, $crop ) {
			if ( ! $crop ) {
				return null;
			} // Let the WordPress default function handle this.

			// Here is the point we allow to use larger image size than the original one.
			$aspect_ratio = $orig_w / $orig_h;
			$new_w        = $dest_w;
			$new_h        = $dest_h;

			if ( ! $new_w ) {
				$new_w = intval( $new_h * $aspect_ratio );
			}

			if ( ! $new_h ) {
				$new_h = intval( $new_w / $aspect_ratio );
			}

			$size_ratio = max( $new_w / $orig_w, $new_h / $orig_h );

			$crop_w = round( $new_w / $size_ratio );
			$crop_h = round( $new_h / $size_ratio );

			$s_x = floor( ( $orig_w - $crop_w ) / 2 );
			$s_y = floor( ( $orig_h - $crop_h ) / 2 );

			return [ 0, 0, (int) $s_x, (int) $s_y, (int) $new_w, (int) $new_h, (int) $crop_w, (int) $crop_h ];
		}
	}
}