<?php

namespace TablePress\PhpOffice\PhpSpreadsheet\Worksheet;

use GdImage;
use TablePress\PhpOffice\PhpSpreadsheet\Exception;
use TablePress\PhpOffice\PhpSpreadsheet\Shared\File;

class MemoryDrawing extends BaseDrawing
{
	// Rendering functions
	const RENDERING_DEFAULT = 'imagepng';
	const RENDERING_PNG = 'imagepng';
	const RENDERING_GIF = 'imagegif';
	const RENDERING_JPEG = 'imagejpeg';

	// MIME types
	const MIMETYPE_DEFAULT = 'image/png';
	const MIMETYPE_PNG = 'image/png';
	const MIMETYPE_GIF = 'image/gif';
	const MIMETYPE_JPEG = 'image/jpeg';

	const SUPPORTED_MIME_TYPES = [
		self::MIMETYPE_GIF,
		self::MIMETYPE_JPEG,
		self::MIMETYPE_PNG,
	];

	/**
				 * Image resource.
				 * @var null|\GdImage
				 */
				private $imageResource = null;

	/**
	 * Rendering function.
	 *
	 * @var callable-string
	 */
	private string $renderingFunction;

	/**
	 * Mime type.
	 */
	private string $mimeType;

	/**
	 * Unique name.
	 */
	private string $uniqueName;

	/**
	 * Create a new MemoryDrawing.
	 */
	public function __construct()
	{
		// Initialise values
		$this->renderingFunction = self::RENDERING_DEFAULT;
		$this->mimeType = self::MIMETYPE_DEFAULT;
		$this->uniqueName = md5(mt_rand(0, 9999) . time() . mt_rand(0, 9999));

		// Initialize parent
		parent::__construct();
	}

	public function __destruct()
	{
		if ($this->imageResource) {
			if (\PHP_VERSION_ID < 80000) {
				@imagedestroy($this->imageResource);
			}
			$this->imageResource = null;
		}
		$this->worksheet = null;
	}

	public function __clone()
	{
		parent::__clone();
		$this->cloneResource();
	}

	private function cloneResource(): void
	{
		if (!$this->imageResource) {
			return;
		}

		$width = (int) imagesx($this->imageResource);
		$height = (int) imagesy($this->imageResource);

		if (imageistruecolor($this->imageResource)) {
			$clone = imagecreatetruecolor($width, $height);
			if (!$clone) {
				throw new Exception('Could not clone image resource');
			}

			imagealphablending($clone, false);
			imagesavealpha($clone, true);
		} else {
			$clone = imagecreate($width, $height);
			if (!$clone) {
				throw new Exception('Could not clone image resource');
			}

			// If the image has transparency...
			$transparent = imagecolortransparent($this->imageResource);
			if ($transparent >= 0) {
				// Starting with Php8.0, next function throws rather than return false
				$rgb = imagecolorsforindex($this->imageResource, $transparent);

				imagesavealpha($clone, true);
				$color = imagecolorallocatealpha($clone, $rgb['red'], $rgb['green'], $rgb['blue'], $rgb['alpha']);
				if ($color === false) {
					throw new Exception('Could not get image alpha color');
				}

				imagefill($clone, 0, 0, $color);
			}
		}

		//Create the Clone!!
		imagecopy($clone, $this->imageResource, 0, 0, 0, 0, $width, $height);

		$this->imageResource = $clone;
	}

	/**
	 * @param resource $imageStream Stream data to be converted to a Memory Drawing
	 *
	 * @throws Exception
	 */
	public static function fromStream($imageStream): self
	{
		$streamValue = stream_get_contents($imageStream);

		return self::fromString($streamValue);
	}

	/**
	 * @param string $imageString String data to be converted to a Memory Drawing
	 *
	 * @throws Exception
	 */
	public static function fromString(string $imageString): self
	{
		$gdImage = @imagecreatefromstring($imageString);
		if ($gdImage === false) {
			throw new Exception('Value cannot be converted to an image');
		}

		$mimeType = self::identifyMimeType($imageString);
		if (imageistruecolor($gdImage) || imagecolortransparent($gdImage) >= 0) {
			imagesavealpha($gdImage, true);
		}
		$renderingFunction = self::identifyRenderingFunction($mimeType);

		$drawing = new self();
		$drawing->setImageResource($gdImage);
		$drawing->setRenderingFunction($renderingFunction);
		$drawing->setMimeType($mimeType);

		return $drawing;
	}

	/** @return callable-string */
	private static function identifyRenderingFunction(string $mimeType): string
	{
		switch ($mimeType) {
									case self::MIMETYPE_PNG:
										return self::RENDERING_PNG;
									case self::MIMETYPE_JPEG:
										return self::RENDERING_JPEG;
									case self::MIMETYPE_GIF:
										return self::RENDERING_GIF;
									default:
										return self::RENDERING_DEFAULT;
								}
	}

	/**
	 * @throws Exception
	 */
	private static function identifyMimeType(string $imageString): string
	{
		$temporaryFileName = File::temporaryFilename();
		file_put_contents($temporaryFileName, $imageString);

		$mimeType = self::identifyMimeTypeUsingGd($temporaryFileName);
		if ($mimeType !== null) {
			unlink($temporaryFileName);

			return $mimeType;
		}

		unlink($temporaryFileName);

		return self::MIMETYPE_DEFAULT;
	}

	/** @internal */
	protected static string $getImageSize = 'getImageSize';

	private static function identifyMimeTypeUsingGd(string $temporaryFileName): ?string
	{
		if (function_exists(static::$getImageSize)) {
			$imageSize = @getimagesize($temporaryFileName);
			if (is_array($imageSize)) {
				$mimeType = $imageSize['mime'];

				return self::supportedMimeTypes($mimeType);
			}
		}

		return null;
	}

	private static function supportedMimeTypes(?string $mimeType = null): ?string
	{
		if (in_array($mimeType, self::SUPPORTED_MIME_TYPES, true)) {
			return $mimeType;
		}

		return null;
	}

	/**
	 * Get image resource.
	 */
	public function getImageResource(): ?GdImage
	{
		return $this->imageResource;
	}

	/**
	 * Set image resource.
	 *
	 * @return $this
	 */
	public function setImageResource(?GdImage $value)
	{
		$this->imageResource = $value;

		if ($this->imageResource !== null) {
			// Get width/height
			$this->width = (int) imagesx($this->imageResource);
			$this->height = (int) imagesy($this->imageResource);
		}

		return $this;
	}

	/**
	 * Get rendering function.
	 *
	 * @return callable-string
	 */
	public function getRenderingFunction(): string
	{
		return $this->renderingFunction;
	}

	/**
	 * Set rendering function.
	 *
	 * @param callable-string $value see self::RENDERING_*
	 *
	 * @return $this
	 */
	public function setRenderingFunction(string $value)
	{
		$this->renderingFunction = $value;

		return $this;
	}

	/**
	 * Get mime type.
	 */
	public function getMimeType(): string
	{
		return $this->mimeType;
	}

	/**
	 * Set mime type.
	 *
	 * @param string $value see self::MIMETYPE_*
	 *
	 * @return $this
	 */
	public function setMimeType(string $value)
	{
		$this->mimeType = $value;

		return $this;
	}

	/**
	 * Get indexed filename (using image index).
	 */
	public function getIndexedFilename(): string
	{
		$extension = strtolower($this->getMimeType());
		$extension = explode('/', $extension);
		$extension = $extension[1];

		return $this->uniqueName . $this->getImageIndex() . '.' . $extension;
	}

	/**
	 * Get hash code.
	 *
	 * @return string Hash code
	 */
	public function getHashCode(): string
	{
		return md5(
			$this->renderingFunction
			. $this->mimeType
			. $this->uniqueName
			. parent::getHashCode()
			. __CLASS__
		);
	}
}
