<?php
/*
 * bfi_thumb - WP Image Resizer v1.3
 *
 * (c) 2013 Benjamin F. Intal / Gambit
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

/** Uses WP's Image Editor Class to resize and filter images
 *
 * @param $url string the local image URL to manipulate
 * @param $params array the options to perform on the image. Keys and values supported:
 *          'width' int pixels
 *          'height' int pixels
 *          'opacity' int 0-100
 *          'color' string hex-color #000000-#ffffff
 *          'grayscale' bool
 *          'negate' bool
 *          'crop' bool
 *          'crop_only' bool
 *          'crop_x' bool string
 *          'crop_y' bool string
 *          'crop_width' bool string
 *          'crop_height' bool string
 *          'quality' int 1-100
 * @param $single boolean, if false then an array of data will be returned
 * @return string|array containing the url of the resized modified image
 */

if ( ! defined( 'ABSPATH' ) ) exit; // Exit if accessed directly

if ( ! function_exists( 'bfi_thumb' ) ) {

    function bfi_thumb( $url, $params = array(), $single = true ) {
        $class = BFI_Class_Factory::getNewestVersion( 'BFI_Thumb' );
        return call_user_func( array( $class, 'thumb' ), $url, $params, $single );
    }

}


/**
 * Class factory, this is to make sure that when multiple bfi_thumb scripts
 * are used (e.g. a plugin and a theme both use it), we always use the
 * latest version.
 */
if ( ! class_exists( 'BFI_Class_Factory' ) ) {

    class BFI_Class_Factory {

        public static $versions = array();
        public static $latestClass = array();


        public static function addClassVersion( $baseClassName, $className, $version ) {
            if ( empty( self::$versions[ $baseClassName ] ) ) {
                self::$versions[ $baseClassName ] = array();
            }
            self::$versions[ $baseClassName ][] = array(
                'class' => $className,
                'version' => $version
            );
        }


        public static function getNewestVersion( $baseClassName ) {
            if ( empty( self::$latestClass[ $baseClassName ] ) ) {
                usort( self::$versions[ $baseClassName ], array( __CLASS__, "versionCompare" ) );
                self::$latestClass[ $baseClassName ] = self::$versions[ $baseClassName ][0]['class'];
                unset( self::$versions[ $baseClassName ] );
            }
            return self::$latestClass[ $baseClassName ];
        }


        public static function versionCompare( $a, $b ) {
            return version_compare( $a['version'], $b['version'] ) == 1 ? -1 : 1;
        }
    }

}



/*
 * Change the default image editors
 */
add_filter( 'wp_image_editors', 'bfi_wp_image_editor' );

// Instead of using the default image editors, use our extended ones
if ( ! function_exists( 'bfi_wp_image_editor' ) ) {

    function bfi_wp_image_editor( $editorArray ) {
        // Make sure that we use the latest versions
        return array(
            BFI_Class_Factory::getNewestVersion( 'BFI_Image_Editor_GD' ),
            BFI_Class_Factory::getNewestVersion( 'BFI_Image_Editor_Imagick' ),
        );
    }

}


/*
 * Include the WP Image classes
 */

require_once ABSPATH . WPINC . '/class-wp-image-editor.php';
require_once ABSPATH . WPINC . '/class-wp-image-editor-imagick.php';
require_once ABSPATH . WPINC . '/class-wp-image-editor-gd.php';


/**
 * check for ImageMagick or GD
 */


add_action( 'admin_init', 'bfi_wp_image_editor_check' );
if ( ! function_exists( 'bfi_wp_image_editor_check' ) ) {

    function bfi_wp_image_editor_check() {
        $arg = array( 'mime_type' => 'image/jpeg' );
        if ( wp_image_editor_supports( $arg ) !== true ) {
            add_filter( 'admin_notices', 'bfi_wp_image_editor_check_notice' );
        }
    }

}

if ( ! function_exists( 'bfi_wp_image_editor_check_notice' ) ) {
    function bfi_wp_image_editor_check_notice() {
        printf( "<div class='error'><p>%s</div>",
            __( "The server does not have ImageMagick or GD installed and/or enabled! Any of these libraries are required for WordPress to be able to resize images. Please contact your server administrator to enable this before continuing.", "default" ) );
    }
}


/*
 * Enhanced Imagemagick Image Editor
 */


if ( ! class_exists( 'BFI_Image_Editor_Imagick_1_3' ) ) {

    BFI_Class_Factory::addClassVersion( 'BFI_Image_Editor_Imagick', 'BFI_Image_Editor_Imagick_1_3', '1.3' );


    class BFI_Image_Editor_Imagick_1_3 extends WP_Image_Editor_Imagick {

        /** Changes the opacity of the image
         *
         * @supports 3.5.1
         * @access public
         *
         * @param float $opacity (0.0-1.0)
         * @return boolean|WP_Error
         */
        public function opacity( $opacity ) {
            $opacity /= 100;

            try {
                // From: http://stackoverflow.com/questions/3538851/php-imagick-setimageopacity-destroys-transparency-and-does-nothing
                // preserves transparency
                //$this->image->setImageOpacity($opacity);
                return $this->image->evaluateImage( Imagick::EVALUATE_MULTIPLY, $opacity, Imagick::CHANNEL_ALPHA );

            } catch ( Exception $e ) {
                return new WP_Error( 'image_opacity_error', $e->getMessage() );
            }
        }


        /** Tints the image a different color
         *
         * @supports 3.5.1
         * @access public
         *
         * @param string hex color e.g. #ff00ff
         * @return boolean|WP_Error
         */
        public function colorize( $hexColor ) {
            try {
                return $this->image->colorizeImage( $hexColor, 1.0 );
            } catch ( Exception $e ) {
                return new WP_Error( 'image_colorize_error', $e->getMessage() );
            }
        }


        /** Makes the image grayscale
         *
         * @supports 3.5.1
         * @access public
         *
         * @return boolean|WP_Error
         */
        public function grayscale() {
            try {
                return $this->image->modulateImage( 100, 0, 100 );
            } catch ( Exception $e ) {
                return new WP_Error( 'image_grayscale_error', $e->getMessage() );
            }
        }


        /** Negates the image
         *
         * @supports 3.5.1
         * @access public
         *
         * @return boolean|WP_Error
         */
        public function negate() {
            try {
                return $this->image->negateImage( false );
            } catch ( Exception $e ) {
                return new WP_Error( 'image_negate_error', $e->getMessage() );
            }
        }
    }
}


/*
 * Enhanced GD Image Editor
 */


if ( ! class_exists( 'BFI_Image_Editor_GD_1_3' ) ) {

    BFI_Class_Factory::addClassVersion( 'BFI_Image_Editor_GD', 'BFI_Image_Editor_GD_1_3', '1.3' );

    class BFI_Image_Editor_GD_1_3 extends WP_Image_Editor_GD {

        /** Rotates current image counter-clockwise by $angle.
         * Ported from image-edit.php
         * Added presevation of alpha channels
         *
         * @since 3.5.0
         * @access public
         *
         * @param float $angle
         * @return boolean|WP_Error
         */
        public function rotate( $angle ) {
            if ( function_exists('imagerotate') ) {
                $rotated = imagerotate( $this->image, $angle, 0 );

                // Add alpha blending
                imagealphablending( $rotated, true );
                imagesavealpha( $rotated, true );

                if ( is_resource( $rotated ) ) {
                    imagedestroy( $this->image );
                    $this->image = $rotated;
                    $this->update_size();
                    return true;
                }
            }

            return new WP_Error( 'image_rotate_error', __( 'Image rotate failed.', 'default' ), $this->file );
        }


        /** Changes the opacity of the image
         *
         * @supports 3.5.1
         * @access public
         *
         * @param float $opacity (0.0-1.0)
         * @return boolean|WP_Error
         */
        public function opacity( $opacity ) {
            $opacity /= 100;

            $filtered = $this->_opacity( $this->image, $opacity );

            if ( is_resource( $filtered ) ) {
                // imagedestroy($this->image);
                $this->image = $filtered;
                return true;
            }

            return new WP_Error( 'image_opacity_error', __('Image opacity change failed.', 'default' ), $this->file );
        }


        // from: http://php.net/manual/en/function.imagefilter.php
        // params: image resource id, opacity (eg. 0.0-1.0)
        protected function _opacity( $image, $opacity ) {
            if ( ! function_exists( 'imagealphablending' ) ||
                 ! function_exists( 'imagecolorat' ) ||
                 ! function_exists( 'imagecolorallocatealpha' ) ||
                 ! function_exists( 'imagesetpixel' ) ) {
                return false;
            }

            // get image width and height
            $w = imagesx( $image );
            $h = imagesy( $image );

            // turn alpha blending off
            imagealphablending( $image, false );

            // find the most opaque pixel in the image (the one with the smallest alpha value)
            $minalpha = 127;
            for ( $x = 0; $x < $w; $x++ ) {
                for ( $y = 0; $y < $h; $y++ ) {
                    $alpha = ( imagecolorat( $image, $x, $y ) >> 24 ) & 0xFF;
                    if ( $alpha < $minalpha ) {
                        $minalpha = $alpha;
                    }
                }
            }

            // loop through image pixels and modify alpha for each
            for ( $x = 0; $x < $w; $x++ ) {
                for ( $y = 0; $y < $h; $y++ ) {

                    // get current alpha value (represents the TANSPARENCY!)
                    $colorxy = imagecolorat( $image, $x, $y );
                    $alpha = ( $colorxy >> 24 ) & 0xFF;

                    // calculate new alpha
                    if ( $minalpha !== 127 ) {
                        $alpha = 127 + 127 * $opacity * ( $alpha - 127 ) / ( 127 - $minalpha );
                    } else {
                        $alpha += 127 * $opacity;
                    }

                    // get the color index with new alpha
                    $alphacolorxy = imagecolorallocatealpha( $image, ( $colorxy >> 16 ) & 0xFF, ( $colorxy >> 8 ) & 0xFF, $colorxy & 0xFF, $alpha );

                    // set pixel with the new color + opacity
                    if( ! imagesetpixel( $image, $x, $y, $alphacolorxy ) ) {
                        return false;
                    }
                }
            }

            imagesavealpha( $image, true );

            return $image;
        }


        /** Tints the image a different color
         *
         * @supports 3.5.1
         * @access public
         *
         * @param string hex color e.g. #ff00ff
         * @return boolean|WP_Error
         */
        public function colorize( $hexColor ) {
            if ( function_exists( 'imagefilter' ) &&
                 function_exists( 'imagesavealpha' ) &&
                 function_exists( 'imagealphablending' ) ) {

                $hexColor = preg_replace( '#^\##', '', $hexColor );
                $r = hexdec( substr( $hexColor, 0, 2 ) );
                $g = hexdec( substr( $hexColor, 2, 2 ) );
                $b = hexdec( substr( $hexColor, 2, 2 ) );

                imagealphablending( $this->image, false );
                if ( imagefilter( $this->image, IMG_FILTER_COLORIZE, $r, $g, $b, 0 ) ) {
                    imagesavealpha( $this->image, true );
                    return true;
                }
            }
            return new WP_Error( 'image_colorize_error', __( 'Image color change failed.', 'default' ), $this->file );
        }


        /** Makes the image grayscale
         *
         * @supports 3.5.1
         * @access public
         *
         * @return boolean|WP_Error
         */
        public function grayscale() {
            if ( function_exists( 'imagefilter' ) ) {
                if ( imagefilter( $this->image, IMG_FILTER_GRAYSCALE ) ) {
                    return true;
                }
            }
            return new WP_Error( 'image_grayscale_error', __( 'Image grayscale failed.', 'default' ), $this->file );
        }


        /** Negates the image
         *
         * @supports 3.5.1
         * @access public
         *
         * @return boolean|WP_Error
         */
        public function negate() {
            if ( function_exists( 'imagefilter' ) ) {
                if ( imagefilter( $this->image, IMG_FILTER_NEGATE ) ) {
                    return true;
                }
            }
            return new WP_Error( 'image_negate_error', __( 'Image negate failed.', 'default' ), $this->file );
        }
    }
}


/*
 * Main Class
 */
if ( ! class_exists( 'BFI_Thumb_1_3' ) ) {

    BFI_Class_Factory::addClassVersion( 'BFI_Thumb', 'BFI_Thumb_1_3', '1.3' );

    class BFI_Thumb_1_3 {

        /** Uses WP's Image Editor Class to resize and filter images
         * Inspired by: https://github.com/sy4mil/Aqua-Resizer/blob/master/aq_resizer.php
         *
         * @param $url string the local image URL to manipulate
         * @param $params array the options to perform on the image. Keys and values supported:
         *          'width' int pixels
         *          'height' int pixels
         *          'opacity' int 0-100
         *          'color' string hex-color #000000-#ffffff
         *          'grayscale' bool
         *          'crop' bool
         *          'negate' bool
         *          'crop_only' bool
         *          'crop_x' bool string
         *          'crop_y' bool string
         *          'crop_width' bool string
         *          'crop_height' bool string
         *          'quality' int 1-100
         * @param $single boolean, if false then an array of data will be returned
         * @return string|array
         */
        public static function thumb( $url, $params = array(), $single = true ) {
            extract( $params );
            global $mk_options;

            //validate inputs
            if ( ! $url ) {
                return false;
            }

            $crop_only = isset( $crop_only ) ? $crop_only : false;

            //define upload path & dir
            $upload_info = wp_upload_dir();
            $upload_dir = $upload_info['basedir'];
            $upload_url = $upload_info['baseurl'];
            $theme_url = get_template_directory_uri();
            $theme_dir = get_template_directory();

            // find the path of the image. Perform 2 checks:
            // #1 check if the image is in the uploads folder
            if ( strpos( $url, $upload_url ) !== false ) {
                $rel_path = str_replace( $upload_url, '', $url );
                $img_path = $upload_dir . $rel_path;

            // #2 check if the image is in the current theme folder
            } else if ( strpos( $url, $theme_url ) !== false ) {
                $rel_path = str_replace( $theme_url, '', $url );
                $img_path = $theme_dir . $rel_path;
            }

            // Fail if we can't find the image in our WP local directory
            if ( empty( $img_path ) ) {
                return $url;
            }

            // check if img path exists, and is an image indeed
            if( ! @file_exists( $img_path ) || ! getimagesize( $img_path ) ) {
                return $url;
            }

            // This is the filename
            $basename = basename( $img_path );

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

            // support percentage dimensions. compute percentage based on
            // the original dimensions
            if ( isset( $width ) ) {
                if ( stripos( $width, '%' ) !== false ) {
                    $width = (int) ( (float) str_replace( '%', '', $width ) / 100 * $orig_w );
                }
            }
            if ( isset( $height ) ) {
                if ( stripos( $height, '%' ) !== false ) {
                    $height = (int) ( (float) str_replace( '%', '', $height ) / 100 * $orig_h );
                }
            }

            // The only purpose of this is to determine the final width and height
            // without performing any actual image manipulation, which will be used
            // to check whether a resize was previously done.
            if ( isset( $width ) && $crop_only === false ) {
                //get image size after cropping
                $dims = image_resize_dimensions( $orig_w, $orig_h, $width, isset( $height ) ? $height : null, isset( $crop ) ? $crop : false );
                $dst_w = $dims[4];
                $dst_h = $dims[5];

            } else if ( $crop_only === true ) {
                // we don't want a resize,
                // but only a crop in the image

                // get x position to start croping
                $src_x = ( isset( $crop_x ) ) ? $crop_x : 0;

                // get y position to start croping
                $src_y = ( isset( $crop_y ) ) ? $crop_y : 0;

                // width of the crop
                if ( isset( $crop_width ) ) {
                    $src_w = $crop_width;
                } else if ( isset( $width ) ) {
                    $src_w = $width;
                } else {
                    $src_w = $orig_w;
                }

                // height of the crop
                if ( isset( $crop_height ) ) {
                    $src_h = $crop_height;
                } else if ( isset( $height ) ) {
                    $src_h = $height;
                } else {
                    $src_h = $orig_h;
                }

                // set the width resize with the crop
                if ( isset( $crop_width ) && isset( $width ) ) {
                    $dst_w = $width;
                } else {
                    $dst_w = null;
                }

                // set the height resize with the crop
                if ( isset( $crop_height ) && isset( $height ) ) {
                    $dst_h = $height;
                } else {
                    $dst_h = null;
                }

                // allow percentages
                if ( isset( $dst_w ) ) {
                    if ( stripos( $dst_w, '%' ) !== false ) {
                        $dst_w = (int) ( (float) str_replace( '%', '', $dst_w ) / 100 * $orig_w );
                    }
                }
                if ( isset( $dst_h ) ) {
                    if ( stripos( $dst_h, '%' ) !== false ) {
                        $dst_h = (int) ( (float) str_replace( '%', '', $dst_h ) / 100 * $orig_h );
                    }
                }

                $dims = image_resize_dimensions( $src_w, $src_h, $dst_w, $dst_h, false );
                $dst_w = $dims[4];
                $dst_h = $dims[5];

                // Make the pos x and pos y work with percentages
                if ( stripos( $src_x, '%' ) !== false ) {
                    $src_x = (int) ( (float) str_replace( '%', '', $width ) / 100 * $orig_w );
                }
                if ( stripos( $src_y, '%' ) !== false ) {
                    $src_y = (int) ( (float) str_replace( '%', '', $height ) / 100 * $orig_h );
                }

                // allow center to position crop start
                if ( $src_x === 'center' ) {
                    $src_x = ( $orig_w - $src_w ) / 2;
                }
                if ( $src_y === 'center' ) {
                    $src_y = ( $orig_h - $src_h ) / 2;
                }
            }

            // create the suffix for the saved file
            // we can use this to check whether we need to create a new file or just use an existing one.
            $suffix = (string) filemtime( $img_path ) .
                ( isset( $width ) ? str_pad( (string) $width, 5, '0', STR_PAD_LEFT ) : '00000' ) .
                ( isset( $height ) ? str_pad( (string) $height, 5, '0', STR_PAD_LEFT ) : '00000' ) .
                ( isset( $opacity ) ? str_pad( (string) $opacity, 3, '0', STR_PAD_LEFT ) : '100' ) .
                ( isset( $color ) ? str_pad( preg_replace( '#^\##', '', $color ), 8, '0', STR_PAD_LEFT ) : '00000000' ) .
                ( isset( $grayscale ) ? ( $grayscale ? '1' : '0' ) : '0' ) .
                ( isset( $crop ) ? ( $crop ? '1' : '0' ) : '0' ) .
                ( isset( $negate ) ? ( $negate ? '1' : '0' ) : '0' ) .
                ( isset( $crop_only ) ? ( $crop_only ? '1' : '0' ) : '0' ) .
                ( isset( $src_x ) ? str_pad( (string) $src_x, 5, '0', STR_PAD_LEFT ) : '00000' ) .
                ( isset( $src_y ) ? str_pad( (string) $src_y, 5, '0', STR_PAD_LEFT ) : '00000' ) .
                ( isset( $src_w ) ? str_pad( (string) $src_w, 5, '0', STR_PAD_LEFT ) : '00000' ) .
                ( isset( $src_h ) ? str_pad( (string) $src_h, 5, '0', STR_PAD_LEFT ) : '00000' ) .
                ( isset( $dst_w ) ? str_pad( (string) $dst_w, 5, '0', STR_PAD_LEFT ) : '00000' ) .
                ( isset( $dst_h ) ? str_pad( (string) $dst_h, 5, '0', STR_PAD_LEFT ) : '00000' ) .
                ( ( isset ( $quality ) && $quality > 0 && $quality <= 100 ) ? ( $quality ? (string) $quality : '0' ) : '0' );
            $suffix = self::base_convert_arbitrary( $suffix, 10, 36 );
            $quality = isset($mk_options['image_resize_quality']) ? $mk_options['image_resize_quality'] : 100;

            // use this to check if cropped image already exists, so we can return that instead
            $dst_rel_path = str_replace( '.' . $ext, '', basename( $img_path ) );

            // If opacity is set, change the image type to png
            if ( isset( $opacity ) ) {
                $ext = 'png';
            }


            // Create the upload subdirectory, this is where
            // we store all our generated images
            if ( defined( 'BFITHUMB_UPLOAD_DIR' ) ) {
                $upload_dir .= "/" . BFITHUMB_UPLOAD_DIR;
                $upload_url .= "/" . BFITHUMB_UPLOAD_DIR;
            } else {
                $upload_dir .= "/bfi_thumb";
                $upload_url .= "/bfi_thumb";
            }
            if ( ! is_dir( $upload_dir ) ) {
                wp_mkdir_p( $upload_dir );
            }


            // desination paths and urls
            $destfilename = "{$upload_dir}/{$dst_rel_path}-{$suffix}.{$ext}";

            // The urls generated have lower case extensions regardless of the original case
            $ext = strtolower( $ext );
            $img_url = "{$upload_url}/{$dst_rel_path}-{$suffix}.{$ext}";

            // if file exists, just return it
            if ( @file_exists( $destfilename ) && getimagesize( $destfilename ) ) {
            } else {
                // perform resizing and other filters
                $editor = wp_get_image_editor( $img_path );

                if ( is_wp_error( $editor ) ) return false;

                /*
                 * Perform image manipulations
                 */
                if ( $crop_only === false ) {
                    if ( ( isset( $width ) && $width ) || ( isset( $height ) && $height ) ) {
                        if ( is_wp_error( $editor->resize( isset( $width ) ? $width : null, isset( $height ) ? $height : null, isset( $crop ) ? $crop : false ) ) ) {
                            return false;
                        }
                    }
                } else {
                    if ( is_wp_error( $editor->crop( $src_x, $src_y, $src_w, $src_h, $dst_w, $dst_h ) ) ) {
                        return false;
                    }
                }

                if ( isset( $negate ) ) {
                    if ( $negate ) {
                        if ( is_wp_error( $editor->negate() ) ) {
                            return false;
                        }
                    }
                }

                if ( isset( $opacity ) ) {
                    if ( is_wp_error( $editor->opacity( $opacity ) ) ) {
                        return false;
                    }
                }

                if ( isset( $grayscale ) ) {
                    if ( $grayscale ) {
                        if ( is_wp_error( $editor->grayscale() ) ) {
                            return false;
                        }
                    }
                }

                if ( isset( $color ) ) {
                    if ( is_wp_error( $editor->colorize( $color ) ) ) {
                        return false;
                    }
                }

                // set the image quality (1-100) to save this image at
                if ( isset( $quality ) && $quality > 0 && $quality <= 100 && $ext != 'png' ) {
                    $editor->set_quality( $quality );
                }

                // save our new image
                $mime_type = isset( $opacity ) ? 'image/png' : null;
                $resized_file = $editor->save( $destfilename, $mime_type );
            }

            //return the output
            if ( $single ) {
                $image = $img_url;
            } else {
                //array return
                $image = array (
                    0 => $img_url,
                    1 => isset( $dst_w ) ? $dst_w : $orig_w,
                    2 => isset( $dst_h ) ? $dst_h : $orig_h,
                );
            }

            return $image;
        }


        /** Shortens a number into a base 36 string
         *
         * @param $number string a string of numbers to convert
         * @param $fromBase starting base
         * @param $toBase base to convert the number to
         * @return string base converted characters
         */
        protected static function base_convert_arbitrary( $number, $fromBase, $toBase ) {
            $digits = '0123456789abcdefghijklmnopqrstuvwxyz';
            $length = strlen( $number );
            $result = '';

            $nibbles = array();
            for ( $i = 0; $i < $length; ++$i ) {
                $nibbles[ $i ] = strpos( $digits, $number[ $i ] );
            }

            do {
                $value = 0;
                $newlen = 0;

                for ( $i = 0; $i < $length; ++$i ) {

                    $value = $value * $fromBase + $nibbles[ $i ];

                    if ( $value >= $toBase ) {
                        $nibbles[ $newlen++ ] = (int) ( $value / $toBase );
                        $value %= $toBase;

                    } else if ( $newlen > 0 ) {
                        $nibbles[ $newlen++ ] = 0;
                    }
                }

                $length = $newlen;
                $result = $digits[ $value ] . $result;
            }
            while ( $newlen != 0 );

            return $result;
        }
    }
}



// don't use the default resizer since we want to allow resizing to larger sizes (than the original one)
// Parts are copied from media.php
// Crop is always applied (just like timthumb)
// Don't use this inside the admin since sometimes images in the media library get resized
if ( ! is_admin() ) {
    add_filter( 'image_resize_dimensions', 'bfi_image_resize_dimensions', 10, 5 );
}

if ( ! function_exists( 'bfi_image_resize_dimensions' ) ) {
    function bfi_image_resize_dimensions( $payload, $orig_w, $orig_h, $dest_w, $dest_h, $crop = false ) {
        $aspect_ratio = $orig_w / $orig_h;

        $new_w = $dest_w;
        $new_h = $dest_h;

        if ( empty( $new_w ) || $new_w < 0  ) {
            $new_w = intval( $new_h * $aspect_ratio );
        }

        if ( empty( $new_h ) || $new_h < 0 ) {
            $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 );
        
        // Safe guard against super large or zero images which might cause 500 errors
        if ( $new_w > 5000 || $new_h > 5000 || $new_w <= 0 || $new_h <= 0 ) {
            return null;
        }

        // the return array matches the parameters to imagecopyresampled()
        // int dst_x, int dst_y, int src_x, int src_y, int dst_w, int dst_h, int src_w, int src_h
        return array( 0, 0, (int) $s_x, (int) $s_y, (int) $new_w, (int) $new_h, (int) $crop_w, (int) $crop_h );
    }
}


// This function allows us to latch on WP image functions such as
// the_post_thumbnail, get_image_tag and wp_get_attachment_image_src
// so that you won't have to use the function bfi_thumb in order to do resizing.
// To make this work, in the WP image functions, when specifying an
// array for the image dimensions, add a 'bfi_thumb' => true to
// the array, then add your normal $params arguments.
//
// e.g. the_post_thumbnail( array( 1024, 400, 'bfi_thumb' => true, 'grayscale' => true ) );
add_filter( 'image_downsize', 'bfi_image_downsize', 1, 3 );

if ( ! function_exists( 'bfi_image_downsize' ) ) {
    function bfi_image_downsize( $out, $id, $size ) {
        if ( ! is_array( $size ) ) {
            return false;
        }
        if ( ! array_key_exists( 'bfi_thumb', $size ) ) {
            return false;
        }
        if ( empty( $size['bfi_thumb'] ) ) {
            return false;
        }

        $img_url = wp_get_attachment_url( $id );

        $params = $size;
        $params['width'] = $size[0];
        $params['height'] = $size[1];

        $resized_img_url = bfi_thumb( $img_url, $params );

        return array( $resized_img_url, $size[0], $size[1], false );
    }
}