<?php
/*
 * Copyright 2009 ZXing authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

namespace Zxing;

/**
 * This object extends LuminanceSource around an array of YUV data returned from the camera driver,
 * with the option to crop to a rectangle within the full data. This can be used to exclude
 * superfluous pixels around the perimeter and speed up decoding.
 *
 * It works for any pixel format where the Y channel is planar and appears first, including
 * YCbCr_420_SP and YCbCr_422_SP.
 *
 * @author dswitkin@google.com (Daniel Switkin)
 */
final class PlanarYUVLuminanceSource extends LuminanceSource
{
	private static int $THUMBNAIL_SCALE_FACTOR = 2;
	private $dataWidth;
	private $dataHeight;
	private $left;
	private $top;

	public function __construct(
		private $yuvData,
		$dataWidth,
		$dataHeight,
		$left,
		$top,
		$width,
		$height,
		$reverseHorizontal
	)
	{
		parent::__construct($width, $height);

		if ($left + $width > $dataWidth || $top + $height > $dataHeight) {
			throw new \InvalidArgumentException("Crop rectangle does not fit within image data.");
		}
		$this->dataWidth = $dataWidth;
		$this->dataHeight = $dataHeight;
		$this->left = $left;
		$this->top = $top;
		if ($reverseHorizontal) {
			$this->reverseHorizontal($width, $height);
		}
	}

	//@Override
	public function getRow($y, $row = null)
	{
		if ($y < 0 || $y >= $this->getHeight()) {
			throw new \InvalidArgumentException("Requested row is outside the image: " + \Y);
		}
		$width = $this->getWidth();
		if ($row == null || (is_countable($row) ? count($row) : 0) < $width) {
			$row = [];//new byte[width];
		}
		$offset = ($y + $this->top) * $this->dataWidth + $this->left;
		$row = arraycopy($this->yuvData, $offset, $row, 0, $width);

		return $row;
	}

	//@Override
	public function getMatrix()
	{
		$width = $this->getWidth();
		$height = $this->getHeight();

		// If the caller asks for the entire underlying image, save the copy and give them the
		// original data. The docs specifically warn that result.length must be ignored.
		if ($width == $this->dataWidth && $height == $this->dataHeight) {
			return $this->yuvData;
		}

		$area = $width * $height;
		$matrix = [];//new byte[area];
		$inputOffset = $this->top * $this->dataWidth + $this->left;

		// If the width matches the full width of the underlying data, perform a single copy.
		if ($width == $this->dataWidth) {
			$matrix = arraycopy($this->yuvData, $inputOffset, $matrix, 0, $area);

			return $matrix;
		}

		// Otherwise copy one cropped row at a time.
		$yuv = $this->yuvData;
		for ($y = 0; $y < $height; $y++) {
			$outputOffset = $y * $width;
			$matrix = arraycopy($this->yuvData, $inputOffset, $matrix, $outputOffset, $width);
			$inputOffset += $this->dataWidth;
		}

		return $matrix;
	}

	// @Override
	public function isCropSupported()
	{
		return true;
	}

	// @Override
	public function crop($left, $top, $width, $height): \Zxing\PlanarYUVLuminanceSource
	{
		return new PlanarYUVLuminanceSource(
			$this->yuvData,
			$this->dataWidth,
			$this->dataHeight,
			$this->left + $left,
			$this->top + $top,
			$width,
			$height,
			false
		);
	}

	public function renderThumbnail()
	{
		$width = (int)($this->getWidth() / self::$THUMBNAIL_SCALE_FACTOR);
		$height = (int)($this->getHeight() / self::$THUMBNAIL_SCALE_FACTOR);
		$pixels = [];//new int[width * height];
		$yuv = $this->yuvData;
		$inputOffset = $this->top * $this->dataWidth + $this->left;

		for ($y = 0; $y < $height; $y++) {
			$outputOffset = $y * $width;
			for ($x = 0; $x < $width; $x++) {
				$grey = ($yuv[$inputOffset + $x * self::$THUMBNAIL_SCALE_FACTOR] & 0xff);
				$pixels[$outputOffset + $x] = (0xFF000000 | ($grey * 0x00010101));
			}
			$inputOffset += $this->dataWidth * self::$THUMBNAIL_SCALE_FACTOR;
		}

		return $pixels;
	}

	/**
	 * @return width of image from {@link #renderThumbnail()}
	 */
	/*
  public int getThumbnailWidth() {
	return getWidth() / THUMBNAIL_SCALE_FACTOR;
  }*/

	/**
	 * @return height of image from {@link #renderThumbnail()}
	 */
	/*
  public int getThumbnailHeight() {
	return getHeight() / THUMBNAIL_SCALE_FACTOR;
  }

  private void reverseHorizontal(int width, int height) {
	byte[] yuvData = this.yuvData;
	for (int y = 0, rowStart = top * dataWidth + left; y < height; y++, rowStart += dataWidth) {
		int middle = rowStart + width / 2;
	  for (int x1 = rowStart, x2 = rowStart + width - 1; x1 < middle; x1++, x2--) {
			byte temp = yuvData[x1];
		yuvData[x1] = yuvData[x2];
		yuvData[x2] = temp;
	  }
	}
  }
*/
}