<?php

// Copyright (C) 2010-2026, the Friendica project
// SPDX-FileCopyrightText: 2010-2026 the Friendica project
//
// SPDX-License-Identifier: AGPL-3.0-or-later

namespace Friendica\Object;

use Exception;
use FFMpeg\Coordinate\TimeCode;
use FFMpeg\FFMpeg;
use Friendica\Core\Cache\Enum\Duration;
use Friendica\Core\System;
use Friendica\DI;
use Friendica\Util\Images;
use Imagick;
use ImagickDraw;
use ImagickPixel;
use GdImage;
use kornrunner\Blurhash\Blurhash;

/**
 * Class to handle images
 */
class Image implements \Stringable
{
	/** @var GdImage|Imagick */
	private $image;

	/*
	 * Put back gd stuff, not everybody have Imagick
	 */
	private $imagick;
	private $width;
	private $height;
	private $valid = false;
	private $outputType;
	private $originType;

	/**
	 * Constructor
	 *
	 * @param string $data     Image data
	 * @param string $type     optional, default ''
	 * @param string $filename optional, default ''
	 * @param bool   $imagick  optional, default 'true'
	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
	 * @throws \ImagickException
	 */
	public function __construct(string $data, string $type = '', private readonly string $filename = '', bool $imagick = true)
	{
		$type = Images::addMimeTypeByDataIfInvalid($type, $data);
		$type = Images::addMimeTypeByExtensionIfInvalid($type, $this->filename);

		if (Images::isSupportedMimeType($type)) {
			$this->originType = $this->outputType = Images::getImageTypeByMimeType($type);
		} elseif (($type == '') || str_starts_with($type, 'image/') || substr($type, 0, 12) == ' application/') {
			$this->originType = IMAGETYPE_UNKNOWN;
			$this->outputType = IMAGETYPE_WEBP;
			DI::logger()->debug('Unhandled image mime type, use WebP instead', ['type' => $type, 'filename' => $this->filename, 'size' => strlen($data)]);
		} else {
			DI::logger()->debug('Unhandled mime type', ['type' => $type, 'filename' => $this->filename, 'size' => strlen($data)]);
			$this->valid = false;
			return;
		}

		$this->imagick = $imagick && $this->useImagick($data);

		if ($this->isImagick() && (empty($data) || $this->loadData($data))) {
			$this->valid = !empty($data);
			return;
		}

		// Failed to load with Imagick, fallback
		$this->imagick = false;

		$this->loadData($data);
	}

	/**
	 * Check if Imagick will be used
	 *
	 * @param string $data
	 * @return boolean
	 */
	private function useImagick(string $data): bool
	{
		if (!class_exists('Imagick')) {
			return false;
		}

		if ($this->outputType == IMAGETYPE_PNG) {
			return true;
		}

		if ($this->originType == IMAGETYPE_GIF) {
			$count = preg_match_all("#\\x00\\x21\\xF9\\x04.{4}\\x00[\\x2C\\x21]#s", $data);
			return ($count > 0);
		}

		return (($this->originType == IMAGETYPE_WEBP) && $this->isAnimatedWebP(substr($data, 0, 90)));
	}

	/**
	 * Detect if a WebP image is animated.
	 * @see https://www.php.net/manual/en/function.imagecreatefromwebp.php#126269
	 * @param string $data
	 * @return boolean
	 */
	private function isAnimatedWebP(string $data)
	{
		$header_format = 'A4Riff/I1Filesize/A4Webp/A4Vp/A74Chunk';
		$header        = @unpack($header_format, $data);

		if (!isset($header['Riff']) || strtoupper($header['Riff']) !== 'RIFF') {
			return false;
		}
		if (!isset($header['Webp']) || strtoupper($header['Webp']) !== 'WEBP') {
			return false;
		}
		if (!isset($header['Vp']) || !str_contains(strtoupper($header['Vp']), 'VP8')) {
			return false;
		}

		return str_contains(strtoupper((string) $header['Chunk']), 'ANIM') || str_contains(strtoupper((string) $header['Chunk']), 'ANMF');
	}

	/**
	 * Destructor
	 *
	 * @return void
	 */
	public function __destruct()
	{
		if ($this->image) {
			if ($this->isImagick()) {
				$this->image->clear();
				$this->image->destroy();
				return;
			}
		}
	}

	/**
	 * @return boolean
	 */
	public function isImagick()
	{
		return $this->imagick;
	}

	/**
	 * Loads image data into handler class
	 *
	 * @param string $data Image data
	 * @return boolean Success
	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
	 * @throws \ImagickException
	 */
	private function loadData(string $data): bool
	{
		if ($this->isImagick()) {
			$this->image = new Imagick();
			try {
				$this->image->readImageBlob($data);
			} catch (Exception $e) {
				// Imagick couldn't use the data
				DI::logger()->debug('Error during readImageBlob', ['message' => $e->getMessage(), 'code' => $e->getCode(), 'trace' => $e->getTraceAsString(), 'previous' => $e->getPrevious(), 'file' => $this->filename]);
				return false;
			}

			/*
			 * Setup the image to the format it will be saved to
			 */
			$this->image->setFormat(Images::getImagickFormatByImageType($this->outputType));

			// Always coalesce, if it is not a multi-frame image it won't hurt anyway
			try {
				$this->image = $this->image->coalesceImages();
			} catch (Exception $e) {
				DI::logger()->debug('Error during coalesceImages', ['message' => $e->getMessage(), 'code' => $e->getCode(), 'trace' => $e->getTraceAsString(), 'previous' => $e->getPrevious(), 'file' => $this->filename]);
				return false;
			}

			/*
			 * setup the compression here, so we'll do it only once
			 */
			switch ($this->getImageType()) {
				case IMAGETYPE_PNG:
					$quality = DI::config()->get('system', 'png_quality');
					/*
					 * From http://www.imagemagick.org/script/command-line-options.php#quality:
					 *
					 * 'For the MNG and PNG image formats, the quality value sets
					 * the zlib compression level (quality / 10) and filter-type (quality % 10).
					 * The default PNG "quality" is 75, which means compression level 7 with adaptive PNG filtering,
					 * unless the image has a color map, in which case it means compression level 7 with no PNG filtering'
					 */
					$quality = $quality * 10;
					$this->image->setImageCompressionQuality($quality);
					break;

				case IMAGETYPE_JPEG:
					$quality = DI::config()->get('system', 'jpeg_quality');
					$this->image->setImageCompressionQuality($quality);
			}

			$this->width  = $this->image->getImageWidth();
			$this->height = $this->image->getImageHeight();
			$this->valid  = true;

			return $this->valid;
		}

		$this->valid = false;

		if (($this->originType == IMAGETYPE_WEBP) && $this->isAnimatedWebP(substr($data, 0, 90))) {
			DI::logger()->notice('Animated WebP images are unsupported by GDlib. Please install Imagick.', ['file' => $this->filename]);
			return false;
		}

		try {
			$this->image = @imagecreatefromstring($data);
			if ($this->image !== false) {
				$this->width  = imagesx($this->image);
				$this->height = imagesy($this->image);
				$this->valid  = true;
				imagealphablending($this->image, false);
				imagesavealpha($this->image, true);
				imageinterlace($this->image, true);

				return true;
			}
		} catch (\Throwable $error) {
			/** @see https://github.com/php/doc-en/commit/d09a881a8e9059d11e756ee59d75bf404d6941ed */
			if (strstr($error->getMessage(), "gd-webp cannot allocate temporary buffer")) {
				DI::logger()->notice('Image is probably animated and therefore unsupported', ['message' => $error->getMessage(), 'code' => $error->getCode(), 'trace' => $error->getTraceAsString(), 'file' => $this->filename]);
			} else {
				DI::logger()->warning('Unexpected throwable.', ['message' => $error->getMessage(), 'code' => $error->getCode(), 'trace' => $error->getTraceAsString(), 'file' => $this->filename]);
			}
		}

		return false;
	}

	/**
	 * @return boolean
	 */
	public function isValid(): bool
	{
		return $this->valid;
	}

	/**
	 * @return mixed
	 */
	public function getWidth()
	{
		if (!$this->isValid()) {
			return false;
		}

		return $this->width;
	}

	/**
	 * @return mixed
	 */
	public function getHeight()
	{
		if (!$this->isValid()) {
			return false;
		}

		return $this->height;
	}

	/**
	 * @return mixed
	 */
	public function getImage()
	{
		if (!$this->isValid()) {
			return false;
		}

		if ($this->isImagick()) {
			try {
				/* Clean it */
				$this->image = $this->image->deconstructImages();
				return $this->image;
			} catch (Exception) {
				return false;
			}
		}
		return $this->image;
	}

	/**
	 * @return mixed
	 */
	public function getType()
	{
		if (!$this->isValid()) {
			return false;
		}

		return image_type_to_mime_type($this->outputType);
	}

	/**
	 * @return mixed
	 */
	public function getImageType()
	{
		if (!$this->isValid()) {
			return false;
		}

		return $this->outputType;
	}

	/**
	 * @return mixed
	 */
	public function getExt()
	{
		if (!$this->isValid()) {
			return false;
		}

		return Images::getExtensionByImageType($this->outputType);
	}

	/**
	 * Scales image down
	 *
	 * @param integer $max max dimension
	 * @return mixed
	 */
	public function scaleDown(int $max)
	{
		if (!$this->isValid()) {
			return false;
		}

		$width  = $this->getWidth();
		$height = $this->getHeight();

		$scale = Images::getScalingDimensions($width, $height, $max);
		if ($scale) {
			return $this->scale($scale['width'], $scale['height']);
		} else {
			return false;
		}
	}

	/**
	 * Rotates image
	 *
	 * @param integer $degrees degrees to rotate image
	 */
	public function rotate(int $degrees): void
	{
		if (!$this->isValid()) {
			return;
		}

		if ($this->isImagick()) {
			$this->image->setFirstIterator();
			do {
				$this->image->rotateImage(new ImagickPixel(), -$degrees); // ImageMagick rotates in the opposite direction of imagerotate()
			} while ($this->image->nextImage());

			$this->width  = $this->image->getImageWidth();
			$this->height = $this->image->getImageHeight();
			return;
		}

		// if script dies at this point check memory_limit setting in php.ini
		$this->image  = imagerotate($this->image, $degrees, 0);
		$this->width  = imagesx($this->image);
		$this->height = imagesy($this->image);
	}

	/**
	 * Flips image
	 *
	 * @param boolean $horiz optional, default true
	 * @param boolean $vert  optional, default false
	 */
	public function flip(bool $horiz = true, bool $vert = false): void
	{
		if (!$this->isValid()) {
			return;
		}

		if ($this->isImagick()) {
			$this->image->setFirstIterator();
			do {
				if ($horiz) {
					$this->image->flipImage();
				}
				if ($vert) {
					$this->image->flopImage();
				}
			} while ($this->image->nextImage());
			return;
		}

		$w       = imagesx($this->image);
		$h       = imagesy($this->image);
		$flipped = imagecreate($w, $h);
		if ($horiz) {
			for ($x = 0; $x < $w; $x++) {
				imagecopy($flipped, $this->image, $x, 0, $w - $x - 1, 0, 1, $h);
			}
		}
		if ($vert) {
			for ($y = 0; $y < $h; $y++) {
				imagecopy($flipped, $this->image, 0, $y, 0, $h - $y - 1, $w, 1);
			}
		}
		$this->image = $flipped;
	}

	/**
	 * Fixes orientation and maybe returns EXIF data (?)
	 *
	 * @param string $filename Filename
	 * @return mixed
	 */
	public function orient(string $filename)
	{
		if ($this->isImagick()) {
			// based off comment on http://php.net/manual/en/imagick.getimageorientation.php
			$orientation = $this->image->getImageOrientation();
			switch ($orientation) {
				case Imagick::ORIENTATION_BOTTOMRIGHT:
					$this->rotate(180);
					break;
				case Imagick::ORIENTATION_RIGHTTOP:
					$this->rotate(-90);
					break;
				case Imagick::ORIENTATION_LEFTBOTTOM:
					$this->rotate(90);
					break;
			}

			$this->image->setImageOrientation(Imagick::ORIENTATION_TOPLEFT);
			return true;
		}
		// based off comment on http://php.net/manual/en/function.imagerotate.php

		if (!$this->isValid()) {
			return false;
		}

		if ((!function_exists('exif_read_data')) || ($this->getImageType() !== IMAGETYPE_JPEG)) {
			return;
		}

		$exif = @exif_read_data($filename, null, true);
		if (!$exif) {
			return;
		}

		$ort = $exif['IFD0']['Orientation'] ?? 1;

		switch ($ort) {
			case 1: // nothing
				break;

			case 2: // horizontal flip
				$this->flip();
				break;

			case 3: // 180 rotate left
				$this->rotate(180);
				break;

			case 4: // vertical flip
				$this->flip(false, true);
				break;

			case 5: // vertical flip + 90 rotate right
				$this->flip(false, true);
				$this->rotate(-90);
				break;

			case 6: // 90 rotate right
				$this->rotate(-90);
				break;

			case 7: // horizontal flip + 90 rotate right
				$this->flip();
				$this->rotate(-90);
				break;

			case 8: // 90 rotate left
				$this->rotate(90);
				break;
		}

		return $exif;
	}

	/**
	 * Rescales image to minimum size
	 *
	 * @param integer $min Minimum dimension
	 * @return mixed
	 */
	public function scaleUp(int $min)
	{
		if (!$this->isValid()) {
			return false;
		}

		$width  = $this->getWidth();
		$height = $this->getHeight();

		if ((!$width) || (!$height)) {
			return false;
		}

		if ($width < $min && $height < $min) {
			if ($width > $height) {
				$dest_width  = $min;
				$dest_height = intval(($height * $min) / $width);
			} else {
				$dest_width  = intval(($width * $min) / $height);
				$dest_height = $min;
			}
		} else {
			if ($width < $min) {
				$dest_width  = $min;
				$dest_height = intval(($height * $min) / $width);
			} else {
				if ($height < $min) {
					$dest_width  = intval(($width * $min) / $height);
					$dest_height = $min;
				} else {
					$dest_width  = $width;
					$dest_height = $height;
				}
			}
		}

		return $this->scale($dest_width, $dest_height);
	}

	/**
	 * Scales image to square
	 *
	 * @param integer $dim Dimension
	 * @return mixed
	 */
	public function scaleToSquare(int $dim)
	{
		if (!$this->isValid()) {
			return false;
		}

		return $this->scale($dim, $dim);
	}

	/**
	 * Scale image to target dimensions
	 *
	 * @param int $dest_width Destination width
	 * @param int $dest_height Destination height
	 * @return boolean Success
	 */
	private function scale(int $dest_width, int $dest_height): bool
	{
		if (!$this->isValid()) {
			return false;
		}
		if ($dest_width <= 0 || $dest_height <= 0) {
			return false;
		}

		if ($this->isImagick()) {
			/*
			 * If it is not animated, there will be only one iteration here,
			 * so don't bother checking
			 */
			// Don't forget to go back to the first frame
			$this->image->setFirstIterator();
			do {
				// FIXME - implement horizontal bias for scaling as in following GD functions
				// to allow very tall images to be constrained only horizontally.
				try {
					$this->image->scaleImage($dest_width, $dest_height);
				} catch (Exception) {
					// Imagick couldn't use the data
					return false;
				}
			} while ($this->image->nextImage());

			$this->width  = $this->image->getImageWidth();
			$this->height = $this->image->getImageHeight();
		} else {
			$dest = imagecreatetruecolor($dest_width, $dest_height);
			imagealphablending($dest, false);
			imagesavealpha($dest, true);

			if ($this->outputType == IMAGETYPE_PNG) {
				imagefill($dest, 0, 0, imagecolorallocatealpha($dest, 0, 0, 0, 127)); // fill with alpha
			}

			imagecopyresampled($dest, $this->image, 0, 0, 0, 0, $dest_width, $dest_height, $this->width, $this->height);

			$this->image  = $dest;
			$this->width  = imagesx($this->image);
			$this->height = imagesy($this->image);
		}

		return true;
	}

	/**
	 * Convert a GIF to a PNG to make it static
	 *
	 * @return void
	 */
	public function toStatic()
	{
		if ($this->outputType != IMAGETYPE_GIF) {
			return;
		}

		if ($this->isImagick()) {
			$this->outputType = IMAGETYPE_PNG;
			$this->image->setFormat(Images::getImagickFormatByImageType($this->outputType));
		}
	}

	/**
	 * Crops image
	 *
	 * @param integer $max maximum
	 * @param integer $x   x coordinate
	 * @param integer $y   y coordinate
	 * @param integer $w   width
	 * @param integer $h   height
	 * @return mixed
	 */
	public function crop(int $max, int $x, int $y, int $w, int $h)
	{
		if (!$this->isValid()) {
			return false;
		}

		if ($this->isImagick()) {
			$this->image->setFirstIterator();
			do {
				$this->image->cropImage($w, $h, $x, $y);
				/*
				 * We need to remove the canvas,
				 * or the image is not resized to the crop:
				 * http://php.net/manual/en/imagick.cropimage.php#97232
				 */
				$this->image->setImagePage(0, 0, 0, 0);
			} while ($this->image->nextImage());
			return $this->scaleDown($max);
		}

		$dest = imagecreatetruecolor($max, $max);
		imagealphablending($dest, false);
		imagesavealpha($dest, true);

		if ($this->outputType == IMAGETYPE_PNG) {
			imagefill($dest, 0, 0, imagecolorallocatealpha($dest, 0, 0, 0, 127)); // fill with alpha
		}
		imagecopyresampled($dest, $this->image, 0, 0, $x, $y, $max, $max, $w, $h);

		$this->image  = $dest;
		$this->width  = imagesx($this->image);
		$this->height = imagesy($this->image);

		// All successful
		return true;
	}

	/**
	 * Magic method allowing string casting of an Image object
	 *
	 * Ex: $data = $Image->asString();
	 * can be replaced by
	 * $data = (string) $Image;
	 *
	 * @return string
	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
	 */
	public function __toString(): string
	{
		return (string) $this->asString();
	}

	/**
	 * Returns image as string or false on failure
	 *
	 * @return mixed
	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
	 */
	public function asString()
	{
		if (!$this->isValid()) {
			return false;
		}

		if ($this->isImagick()) {
			try {
				/* Clean it */
				$this->image = $this->image->deconstructImages();
				return $this->image->getImagesBlob();
			} catch (Exception) {
				return false;
			}
		}

		$stream = fopen('php://memory', 'r+');

		switch ($this->getImageType()) {
			case IMAGETYPE_PNG:
				$quality = DI::config()->get('system', 'png_quality');
				imagepng($this->image, $stream, $quality);
				break;

			case IMAGETYPE_JPEG:
				$quality = DI::config()->get('system', 'jpeg_quality');
				imagejpeg($this->image, $stream, $quality);
				break;

			case IMAGETYPE_GIF:
				imagegif($this->image, $stream);
				break;

			case IMAGETYPE_WEBP:
				@imagewebp($this->image, $stream, DI::config()->get('system', 'jpeg_quality'));
				break;

			case IMAGETYPE_BMP:
				imagebmp($this->image, $stream);
				break;
		}
		rewind($stream);
		return stream_get_contents($stream);
	}

	/**
	 * Create a blurhash out of a given image string
	 *
	 * @return string
	 */
	public function getBlurHash(string $img_str = ''): string
	{
		$image = new Image($img_str ?: $this->asString(), $this->getType(), $this->filename, false);
		if (!$this->isValid()) {
			return '';
		}

		$width  = $image->getWidth();
		$height = $image->getHeight();

		if (max($width, $height) > 90) {
			$image->scaleDown(90);
			$width  = $image->getWidth();
			$height = $image->getHeight();
		}

		if (empty($width) || empty($height)) {
			return '';
		}

		$pixels = [];
		for ($y = 0; $y < $height; ++$y) {
			$row = [];
			for ($x = 0; $x < $width; ++$x) {
				if ($image->isImagick()) {
					try {
						$colors = $image->image->getImagePixelColor($x, $y)->getColor();
					} catch (\Exception) {
						return '';
					}
					$row[] = [$colors['r'], $colors['g'], $colors['b']];
				} else {
					$index  = imagecolorat($image->image, $x, $y);
					$colors = @imagecolorsforindex($image->image, $index);
					$row[]  = [$colors['red'], $colors['green'], $colors['blue']];
				}
			}
			$pixels[] = $row;
		}

		// The components define the amount of details (1 to 9).
		$components_x = 9;
		$components_y = 9;

		return Blurhash::encode($pixels, $components_x, $components_y);
	}

	/**
	 * Create an image out of a blurhash
	 *
	 * @param string $blurhash
	 * @param integer $width
	 * @param integer $height
	 * @return void
	 */
	public function getFromBlurHash(string $blurhash, int $width, int $height)
	{
		$scaled = Images::getScalingDimensions($width, $height, 90);
		$pixels = Blurhash::decode($blurhash, $scaled['width'], $scaled['height']);
		$draw   = null;

		if ($this->isImagick()) {
			$this->image = new Imagick();
			$draw        = new ImagickDraw();
			$this->image->newImage($scaled['width'], $scaled['height'], '', 'png');
		} else {
			$this->image = imagecreatetruecolor($scaled['width'], $scaled['height']);
		}

		for ($y = 0; $y < $scaled['height']; ++$y) {
			for ($x = 0; $x < $scaled['width']; ++$x) {
				[$r, $g, $b] = $pixels[$y][$x];
				if ($draw !== null) {
					$draw->setFillColor("rgb($r, $g, $b)");
					$draw->point($x, $y);
				} else {
					imagesetpixel($this->image, $x, $y, imagecolorallocate($this->image, $r, $g, $b));
				}
			}
		}

		if ($draw !== null) {
			$this->image->drawImage($draw);
			$this->width  = $this->image->getImageWidth();
			$this->height = $this->image->getImageHeight();
		} else {
			$this->width  = imagesx($this->image);
			$this->height = imagesy($this->image);
		}

		$this->valid = true;

		$this->scaleUp(min($width, $height));
	}

	/**
	 * Create a preview image for the provided video URL using ffmpeg.
	 * The result is cached for one day.
	 *
	 * @param string $url Video URL
	 * @return string binary image data or empty string
	 */
	private function getPreviewImageForVideoUrlCached(string $url): string
	{
		$cacheKey = 'getPreviewImageForVideoUrl:' . sha1($url);

		$preview = DI::cache()->get($cacheKey);

		if (!$preview) {
			$preview = $this->getPreviewImageForVideoUrl($url);
			if (!$preview) {
				return '';
			}

			DI::cache()->set($cacheKey, base64_encode($preview), Duration::DAY);
		} else {
			$preview = base64_decode((string) $preview);
		}

		return $preview;
	}

	/**
	 * Create a preview image for the provided video URL using ffmpeg
	 *
	 * @param string $url Video URL
	 * @return string binary image data or empty string
	 */
	private function getPreviewImageForVideoUrl($url): string
	{
		$preview = '';

		$timestamp = microtime(true);

		try {
			$ffmpeg = FFMpeg::create();
			/** @var \FFMpeg\Media\Video $video */
			$video = $ffmpeg->open($url);
			$frame = $video->frame(TimeCode::fromSeconds(0));

			$tempfile = tempnam(System::getTempPath(), 'videopreview-');
			$frame->save($tempfile);
			$preview = file_get_contents($tempfile);
			unlink($tempfile);
			$runtime = number_format(microtime(true) - $timestamp, 3);
			DI::logger()->debug('Created video preview', ['runtime' => $runtime, 'url' => $url]);
		} catch (\Throwable $th) {
			$runtime = number_format(microtime(true) - $timestamp, 3);
			DI::logger()->notice('Got exception', ['runtime' => $runtime, 'url' => $url, 'code' => $th->getCode(), 'message' => $th->getMessage()]);
		}

		return $preview;
	}

	/**
	 * Create a preview image for the provided video URL using ffmpeg
	 *
	 * @param string $url Video URL
	 * @param bool   $cached optional, default true
	 * @return boolean Success
	 */
	public function getFromVideoUrl(string $url, bool $cached = true): bool
	{
		if (!$url) {
			return false;
		}

		if (!DI::config()->get('system', 'ffmpeg_installed')) {
			return false;
		}

		if ($cached) {
			$data = $this->getPreviewImageForVideoUrlCached($url);
		} else {
			$data = $this->getPreviewImageForVideoUrl($url);
		}

		return($this->loadData($data));
	}

}
