<?php

class Image {
    private $image;
    private $filename;
    private $width;
    private $height;

    public function __construct($filename_with_path) {
        $this->filename = $filename_with_path;
        $this->image = $this->loadImage();
    }

    /**
     * @param type $save_as_filename Just filename, NOT full path. DO NOT include the file extension, .png will be added automatically. Will be saved to ~/resources/images/profile/[$save_as_filename].png
     */
    public function saveProfilePicture($save_as_filename) { // Relative filename
        $filename_with_path = BASE_PATH . '/resources/images/profiles/' . $save_as_filename;
        $this->saveFile($filename_with_path . '.png', 1024, 1024, False); // Save full-size image
        $this->saveFile($filename_with_path . '-32.png', 32, 32, True);
        $this->saveFile($filename_with_path . '-48.png', 48, 48, True);
        $this->saveFile($filename_with_path . '-64.png', 64, 64, True);
        $this->saveFile($filename_with_path . '-128.png', 128, 128, True);
        $this->saveFile($filename_with_path . '-256.png', 256, 256, True);
    }

    /**
     * @param type $save_as_filename Just filename, NOT full path. DO NOT include the file extension, .png will be added automatically. Will be saved to ~/resources/images/lists/[$save_as_filename].png
     */
    public function saveListLogo($save_as_filename) { // Relative filename
        $filename_with_path = BASE_PATH . '/resources/images/lists/' . $save_as_filename;
        $this->saveFile($filename_with_path . '.png', 1024, 1024, False); // Save full-size image
        $this->saveFile($filename_with_path . '-32.png', 32, 32, False);
        $this->saveFile($filename_with_path . '-48.png', 48, 48, False);
        $this->saveFile($filename_with_path . '-64.png', 64, 64, False);
        $this->saveFile($filename_with_path . '-128.png', 128, 128, False);
        $this->saveFile($filename_with_path . '-256.png', 256, 256, False);
    }

    /**
     *
     * @param type $filename_with_path
     * @param type $width Optional.
     * @param type $height Optional.
     * @param type $crop_to_dimensions Optional. Crops image to the desired dimensions.
     */
    public function saveFile($filename_with_path, $width, $height, $crop_to_dimensions = False) {
        $resizedImage = $this->resizeImage($width, $height, $crop_to_dimensions);
        imagePng($resizedImage, $filename_with_path, 9, PNG_ALL_FILTERS);
    }

    public function loadImage() {
        $image_info = getImageSize($this->filename); // http://www.php.net/manual/en/function.getimagesize.php
        $this->width = $image_info[0];
        $this->height = $image_info[1];

        // Check if there was an error calling getImageSize():
        if($image_info === False) {
            throw new Exception('Unable to grab image size');
            return;
        }

        // Define function names for possibly returned mime types
        $image_functions = array(
            IMAGETYPE_GIF  => 'imageCreateFromGif',
            IMAGETYPE_JPEG => 'imageCreateFromJpeg',
            IMAGETYPE_PNG  => 'imageCreateFromPng',
            IMAGETYPE_WBMP => 'imageCreateFromwBmp',
            IMAGETYPE_XBM  => 'imageCreateFromwXbm',
        );

        // Check if there was an error calling getImageSize():
        if(!function_exists($image_functions[$image_info[2]])) {
            throw new Exception('Unknown file type');
            return;
        }

        $image = $image_functions[$image_info[2]]($this->filename);
        imageAlphaBlending($image, False);
        imageSaveAlpha($image, True);

        return $image;
    }

    public function getFileExtension() {
        $file_extension = pathinfo($this->filename, PATHINFO_EXTENSION);
        return strtolower($file_extension);
    }

    function resizeImage($target_width, $target_height, $crop_to_dimensions = False) {
        //print 'Original: ' . $this->width . 'x' . $this->height . '<br />';

        if($crop_to_dimensions === True) {
            $width_ratio = $target_width / $this->width;
            //print 'Width Ratio: ' . $width_ratio . '<br />';
            $height_ratio = $target_height / $this->height;
            //print 'Height Ratio: ' . $height_ratio . '<br />';
            if($width_ratio > $height_ratio) {
                //print 'Width Wins<br />';
                $resized_width = $target_width;
                $resized_height = $this->height * $width_ratio;
            } else {
                //print 'Height Wins<br />';
                $resized_height = $target_height;
                $resized_width = $this->width * $height_ratio;
            }
        } else {
            $width_ratio = $target_width / $this->width;
            //print 'Width Ratio: ' . $width_ratio . '<br />';
            $resized_width = $target_width;
            $resized_height = $this->height * $width_ratio;
            //print 'Resized: ' . $resized_width . 'x' . $resized_height . '<br />';
            if($resized_height > $target_height) {
                $height_ratio = $target_height / $resized_height;
                $resized_height = $target_height;
                //print 'Height Ratio: ' . $height_ratio . '<br />';
                $resized_width = $resized_width * $height_ratio;
                //print 'Resized: ' . $resized_width . 'x' . $resized_height . '<br />';
            }
        }

        // Drop decimal values
        $resized_width = round($resized_width);
        $resized_height = round($resized_height);

        // Calculations for centering the image
        $offset_width = round(($target_width - $resized_width) / 2);
        $offset_height = round(($target_height - $resized_height) / 2);

        //print 'Width Offset: ' . $offset_width . '<br />';
        //print 'Height Offset: ' . $offset_height . '<br />';

        $new_image = imageCreateTrueColor($target_width, $target_height);
        imageAlphaBlending($new_image, False);
        imageSaveAlpha($new_image, True);
        $transparent = imageColorAllocateAlpha($new_image, 0, 0, 0, 127);
        imagefill($new_image, 0, 0, $transparent);

        imageCopyResampled($new_image, $this->image, $offset_width, $offset_height, 0, 0, $resized_width, $resized_height, $this->width, $this->height);

        //print 'Final: ' . $resized_width . 'x' . $resized_height . '<br /><br /><br />';
        return $new_image;
    }

    function resizeToHeight($original_width, $original_height, $desired_height) {
        //print 'resize height: ' . $desired_height . '<br />';
        $ratio = $desired_height / $original_height;
        //print '- ratio: ' . $ratio . '<br />';
        $width = $original_width * $ratio;
        //print '- new width: ' . $width . '<br />';
        //print '- new height: ' . $desired_height . '<br />';
        return array(
            'width' => $width,
            'height' => $desired_height
        );
    }

    function resizeToWidth($original_width, $original_height, $desired_width) {
        $ratio = $desired_width / $original_width;
        $height = $original_height * $ratio;
        return array(
            'width' => $desired_width,
            'height' => $height
        );
    }
}