julienmonnerie/kirby/src/Image/Exif.php

<?php

namespace Kirby\Image;

use Kirby\Toolkit\V;

/**
 * Reads exif data from a given image object
 *
 * @package   Kirby Image
 * @author    Bastian Allgeier <bastian@getkirby.com>
 * @link      https://getkirby.com
 * @copyright Bastian Allgeier
 * @license   https://opensource.org/licenses/MIT
 */
class Exif
{
	/**
	 * the parent image object
	 * @var \Kirby\Image\Image
	 */
	protected $image;

	/**
	 * the raw exif array
	 * @var array
	 */
	protected $data = [];

	/**
	 * the camera object with model and make
	 * @var Camera
	 */
	protected $camera;

	/**
	 * the location object
	 * @var Location
	 */
	protected $location;

	/**
	 * the timestamp
	 *
	 * @var string
	 */
	protected $timestamp;

	/**
	 * the exposure value
	 *
	 * @var string
	 */
	protected $exposure;

	/**
	 * the aperture value
	 *
	 * @var string
	 */
	protected $aperture;

	/**
	 * iso value
	 *
	 * @var string
	 */
	protected $iso;

	/**
	 * focal length
	 *
	 * @var string
	 */
	protected $focalLength;

	/**
	 * color or black/white
	 * @var bool
	 */
	protected $isColor;

	/**
	 * Constructor
	 *
	 * @param \Kirby\Image\Image $image
	 */
	public function __construct(Image $image)
	{
		$this->image = $image;
		$this->data  = $this->read();
		$this->parse();
	}

	/**
	 * Returns the raw data array from the parser
	 *
	 * @return array
	 */
	public function data(): array
	{
		return $this->data;
	}

	/**
	 * Returns the Camera object
	 *
	 * @return \Kirby\Image\Camera|null
	 */
	public function camera()
	{
		if ($this->camera !== null) {
			return $this->camera;
		}

		return $this->camera = new Camera($this->data);
	}

	/**
	 * Returns the location object
	 *
	 * @return \Kirby\Image\Location|null
	 */
	public function location()
	{
		if ($this->location !== null) {
			return $this->location;
		}

		return $this->location = new Location($this->data);
	}

	/**
	 * Returns the timestamp
	 *
	 * @return string|null
	 */
	public function timestamp()
	{
		return $this->timestamp;
	}

	/**
	 * Returns the exposure
	 *
	 * @return string|null
	 */
	public function exposure()
	{
		return $this->exposure;
	}

	/**
	 * Returns the aperture
	 *
	 * @return string|null
	 */
	public function aperture()
	{
		return $this->aperture;
	}

	/**
	 * Returns the iso value
	 *
	 * @return int|null
	 */
	public function iso()
	{
		return $this->iso;
	}

	/**
	 * Checks if this is a color picture
	 *
	 * @return bool|null
	 */
	public function isColor()
	{
		return $this->isColor;
	}

	/**
	 * Checks if this is a bw picture
	 *
	 * @return bool|null
	 */
	public function isBW(): ?bool
	{
		return ($this->isColor !== null) ? $this->isColor === false : null;
	}

	/**
	 * Returns the focal length
	 *
	 * @return string|null
	 */
	public function focalLength()
	{
		return $this->focalLength;
	}

	/**
	 * Read the exif data of the image object if possible
	 *
	 * @return mixed
	 */
	protected function read(): array
	{
		// @codeCoverageIgnoreStart
		if (function_exists('exif_read_data') === false) {
			return [];
		}
		// @codeCoverageIgnoreEnd

		$data = @exif_read_data($this->image->root());
		return is_array($data) ? $data : [];
	}

	/**
	 * Get all computed data
	 *
	 * @return array
	 */
	protected function computed(): array
	{
		return $this->data['COMPUTED'] ?? [];
	}

	/**
	 * Pareses and stores all relevant exif data
	 */
	protected function parse()
	{
		$this->timestamp   = $this->parseTimestamp();
		$this->exposure    = $this->data['ExposureTime'] ?? null;
		$this->iso         = $this->data['ISOSpeedRatings'] ?? null;
		$this->focalLength = $this->parseFocalLength();
		$this->aperture    = $this->computed()['ApertureFNumber'] ?? null;
		$this->isColor     = V::accepted($this->computed()['IsColor'] ?? null);
	}

	/**
	 * Return the timestamp when the picture has been taken
	 *
	 * @return string|int
	 */
	protected function parseTimestamp()
	{
		if (isset($this->data['DateTimeOriginal']) === true) {
			return strtotime($this->data['DateTimeOriginal']);
		}

		return $this->data['FileDateTime'] ?? $this->image->modified();
	}

	/**
	 * Return the focal length
	 *
	 * @return string|null
	 */
	protected function parseFocalLength()
	{
		return $this->data['FocalLength'] ?? $this->data['FocalLengthIn35mmFilm'] ?? null;
	}

	/**
	 * Converts the object into a nicely readable array
	 *
	 * @return array
	 */
	public function toArray(): array
	{
		return [
			'camera'      => $this->camera() ? $this->camera()->toArray() : null,
			'location'    => $this->location() ? $this->location()->toArray() : null,
			'timestamp'   => $this->timestamp(),
			'exposure'    => $this->exposure(),
			'aperture'    => $this->aperture(),
			'iso'         => $this->iso(),
			'focalLength' => $this->focalLength(),
			'isColor'     => $this->isColor()
		];
	}

	/**
	 * Improved `var_dump` output
	 *
	 * @return array
	 */
	public function __debugInfo(): array
	{
		return array_merge($this->toArray(), [
			'camera'   => $this->camera(),
			'location' => $this->location()
		]);
	}
}