<?php

namespace Automad\Core;

/**
 * The Image object represents a resized (and cropped) copy of a given image.
 *
 * @author Marc Anton Dahmen
 * @copyright Copyright (c) 2013-2023 by Marc Anton Dahmen - https://marcdahmen.de
 * @license MIT license - https://automad.org/license
 */
class Image
{
	/** The filename of generated image. */
	public string $file = '';

	/** The height of the generated image. */
	public int $height = 0;

	/** The height of the source image. */
	public float $originalHeight = 0;

	/** The width of the source image. */
	public float $originalWidth = 0;

	/** The width of the generated image. */
	public int $width = 0;

	/** Cropping parameter. */
	private bool $crop = false;

	/** The pixels to crop the image on the X-axis on both sides. */
	private int $cropX = 0;

	/** The pixels to crop the image on the Y-axis on both sides. */
	private int $cropY = 0;

	/** The full file system path to the generated image. */
	private string $fileFullPath = '';

	/** The filename of the source image */
	private string $originalFile;

	/** The desired height of the new image. (May not be the resulting width, depending on cropping or original image size) */
	private float $requestedHeight = 0;

	/** The disired width of the new image. (May not be the resulting width, depending on cropping or original image size) */
	private float $requestedWidth = 0;

	/** The given image type. */
	private string $type = '';


	/**
	 * The constructor defines the main object properties from the given parameters and initiates the main methods.
	 *
	 * @param string $originalFile
	 * @param float|string $requestedWidth
	 * @param float|string $requestedHeight
	 * @param bool $crop
	 */
	public function __construct(
		string $originalFile,
		float|string $requestedWidth = 0,
		float|string $requestedHeight = 0,
		bool $crop = false,
	) {
		$this->originalFile = $originalFile;

		if (!$originalFile) {
			return;
		}

		$requestedWidth = floatval($requestedWidth);
		$requestedHeight = floatval($requestedHeight);

		ini_set('memory_limit', '-1');

		$getimagesize = @getimagesize($originalFile);

		if (!$getimagesize) {
			return;
		}

		$this->originalWidth = $getimagesize[0];
		$this->originalHeight = $getimagesize[1];

		$this->requestedWidth = $requestedWidth ? $requestedWidth : $this->originalWidth;
		$this->requestedHeight = $requestedHeight ? $requestedHeight : $this->originalHeight;

		$this->type = $getimagesize['mime'];
		$this->crop = $crop;

		// Get the possible size for the generated image (based on crop and original size).
		$this->calculateSize();

		// Get the filename hash, based on the given settings, to check later, if the file exists.
		$this->file = $this->getImageCacheFilePath();
		$this->fileFullPath = AM_BASE_DIR . $this->file;

		// Check if an image with the generated hash exists already and create the file, when neccassary.
		$this->verifyCachedImage();
	}


	/**
	 * Calculate the size and pixels to crop for the generated image.
	 */
	private function calculateSize(): void
	{
		if (!$this->originalWidth || !$this->originalHeight || !$this->requestedWidth || !$this->requestedHeight) {
			return;
		}

		$originalAspect = $this->originalWidth / $this->originalHeight;
		$requestedAspect = $this->requestedWidth / $this->requestedHeight;

		if ($this->crop) {
			// Crop image

			if ($originalAspect > $requestedAspect) {
				if ($this->requestedWidth < $this->originalWidth) {
					$w = $this->requestedWidth;
				} else {
					$w = $this->originalWidth;
				}

				$h = $w / $requestedAspect;

				if ($h > $this->originalHeight) {
					$h = $this->originalHeight;
					$requestedAspect = $w / $h;
				}

				// crop X
				$x = ($this->originalWidth - ($this->originalHeight * $requestedAspect)) / 2;
				$y = 0;
			} else {
				if ($this->requestedHeight < $this->originalHeight) {
					$h = $this->requestedHeight;
				} else {
					$h = $this->originalHeight;
				}

				$w = $h * $requestedAspect;

				if ($w > $this->originalWidth) {
					$w = $this->originalWidth;
					$requestedAspect = $w / $h;
				}

				// crop X
				$x = 0;
				$y = ($this->originalHeight - ($this->originalWidth / $requestedAspect)) / 2;
			}
		} else {
			// No cropping

			$x = 0;
			$y = 0;

			if ($originalAspect > $requestedAspect) {
				if ($this->requestedWidth < $this->originalWidth) {
					$w = $this->requestedWidth;
				} else {
					$w = $this->originalWidth;
				}

				$h = $w / $originalAspect;
			} else {
				if ($this->requestedHeight < $this->originalHeight) {
					$h = $this->requestedHeight;
				} else {
					$h = $this->originalHeight;
				}

				$w = $h * $originalAspect;
			}
		}

		$this->width = (int) round($w);
		$this->height = (int) round($h);
		$this->cropX = (int) round($x);
		$this->cropY = (int) round($y);
	}


	/**
	 * Create a new (resized and cropped) image from the source image and save that image in the cache directory.
	 */
	private function createImage(): void
	{
		switch ($this->type) {
			case 'image/jpeg':
				$src = imagecreatefromjpeg($this->originalFile);

				break;
			case 'image/gif':
				$src = imagecreatefromgif($this->originalFile);

				break;
			case 'image/png':
				$src = imagecreatefrompng($this->originalFile);

				break;
			case 'image/webp':
				$src = imagecreatefromwebp($this->originalFile);

				break;
			default:
				$src = false;

				break;
		}

		if (!$src) {
			return;
		}

		$dest = imagecreatetruecolor($this->width, $this->height);

		imagealphablending($dest, false);
		imagesavealpha($dest, true);
		imagecopyresampled(
			$dest,
			$src,
			0,
			0,
			$this->cropX,
			$this->cropY,
			$this->width,
			$this->height,
			(int) round($this->originalWidth - (2 * $this->cropX)),
			(int) round($this->originalHeight - (2 * $this->cropY))
		);

		Debug::log($this, 'Saving "' . $this->fileFullPath . '"');

		// Create cache directory, if not existing.
		FileSystem::makeDir(AM_BASE_DIR . Cache::DIR_IMAGES);

		switch ($this->type) {
			case 'image/jpeg':
				imagejpeg($dest, $this->fileFullPath, AM_IMG_JPG_QUALITY);

				break;
			case 'image/gif':
				imagegif($dest, $this->fileFullPath);

				break;
			case 'image/png':
				imagepng($dest, $this->fileFullPath);

				break;
			case 'image/webp':
				imagewebp($dest, $this->fileFullPath);

				break;
		}

		chmod($this->fileFullPath, AM_PERM_FILE);
	}


	/**
	 * Determine the corresponding image file to a source file based on a md5 hash.
	 * That hash is based on the source image's path, mtime, the new width and height and the cropping parameter.
	 * If one parameter changes, the hash will be different, which will result in recreating an image.
	 * Since the mtime is part of the hash, also any modification to the source image will be reflected in a different name.
	 * For each size and cropping setting, a unique filename will be returned, to clearly identify that setting.
	 *
	 * @return string The matching filename for the requested source image, based on its parameters
	 */
	private function getImageCacheFilePath(): string
	{
		$extension = strtolower(pathinfo($this->originalFile, PATHINFO_EXTENSION));

		if ($extension == 'jpeg') {
			$extension = 'jpg';
		}

		// Create unique filename in the cache folder:
		// The hash makes it possible to clearly identify an unchanged file in the cache,
		// since the given hashData will always result in the same hash.
		// So if a file gets requested, the hash is generated from the path, calculated width x height, the mtime from the original and the cropping setting.
		$hashData = $this->originalFile . '-' . $this->width . 'x' . $this->height . '-' . filemtime($this->originalFile) . '-' . var_export($this->crop, true);
		$hash = sha1($hashData);

		$file = Cache::DIR_IMAGES . '/' . $hash . '.' . $extension;

		Debug::log($hashData, 'Hash data for ' . $hash);

		return $file;
	}


	/**
	 * To verify, if the requested image is up to date, only the existence has to be tested,
	 * since any changes in the source image will be reflected in the filename's hash.
	 */
	private function verifyCachedImage(): void
	{
		if (!file_exists($this->fileFullPath)) {
			$this->createImage();
		}
	}
}
__halt_compiler();----SIGNATURE:----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----ATTACHMENT:----NTQ1MDQyMTkyMTk1MTE2NSA5NDY5NzM5ODM2MTA2Mzc2IDQwODY0MTgwMTI2NDcxNDM=