<?php

namespace App\Services;

use App\Album;
use App\AlbumSources\IAlbumSource;
use App\Helpers\ImageHelper;
use App\Helpers\ThemeHelper;
use App\Photo;

class PhotoService
{
    const METADATA_VERSION = 1;

    /**
     * @var Album
     */
    private $album;

    /**
     * @var IAlbumSource
     */
    private $albumSource;

    /**
     * @var ImageHelper
     */
    private $imageHelper;

    /**
     * @var Photo
     */
    private $photo;

    /**
     * @var ThemeHelper
     */
    private $themeHelper;

    public function __construct(Photo $photo)
    {
        $this->photo = $photo;
        $this->album = $photo->album;
        $this->albumSource = $this->album->getAlbumSource();

        $this->imageHelper = new ImageHelper();
        $this->themeHelper = new ThemeHelper();
    }

    public function analyse()
    {
        /** @var Album $album */
        $album = $this->photo->album;
        $albumSource = $album->getAlbumSource();

        $photoFile = $albumSource->getPathToPhoto($this->photo);

        $imageInfo = null;
        $originalPhotoResource = $this->imageHelper->openImage($photoFile, $imageInfo);
        if ($originalPhotoResource === false)
        {
            throw new \Exception(sprintf('The image "%s" does not appear to be a valid image, or cannot be read', pathinfo($photoFile, PATHINFO_FILENAME)));
        }

        $this->photo->width = $imageInfo[0];
        $this->photo->height = $imageInfo[1];
        $this->photo->mime_type = $imageInfo['mime'];

        // Read the Exif data
        $exifData = @exif_read_data($photoFile);
        $isExifDataFound = ($exifData !== false && is_array($exifData));
        $angleToRotate = 0;

        // If Exif data contains an Orientation, ensure we rotate the original image as such
        if ($isExifDataFound && isset($exifData['Orientation']))
        {
            switch ($exifData['Orientation'])
            {
                case 3:
                    $angleToRotate = 180;
                    break;

                case 6:
                    $angleToRotate = 270;
                    break;

                case 8:
                    $angleToRotate = 90;
                    break;
            }

            if ($angleToRotate > 0)
            {
                $originalPhotoResource = $this->imageHelper->rotateImage($originalPhotoResource, $angleToRotate);

                if ($angleToRotate == 90 || $angleToRotate == 270)
                {
                    $this->photo->width = $imageInfo[1];
                    $this->photo->height = $imageInfo[0];
                }

                $this->imageHelper->saveImage($originalPhotoResource, $photoFile, $imageInfo);
            }
        }

        if ($isExifDataFound)
        {
            $this->photo->metadata_version = self::METADATA_VERSION;
            $this->photo->taken_at = $this->metadataDateTime($exifData);
            $this->photo->camera_make = $this->metadataCameraMake($exifData);
            $this->photo->camera_model = $this->metadataCameraModel($exifData);
            $this->photo->camera_software = $this->metadataCameraSoftware($exifData);
        }

        $this->photo->is_analysed = true;
        $this->photo->save();

        $this->regenerateThumbnails($originalPhotoResource);
    }

    public function regenerateThumbnails($originalPhotoResource = null)
    {
        if (is_null($originalPhotoResource))
        {
            $imageInfo = null;
            $originalPhotoResource = $this->imageHelper->openImage($this->albumSource->getPathToPhoto($this->photo), $imageInfo);
        }

        // Generate and save thumbnails
        $themeInfo = $this->themeHelper->info();
        $thumbnailsRequired = $themeInfo['thumbnails'];

        /** @var mixed $thumbnail */
        foreach ($thumbnailsRequired as $thumbnail)
        {
            $generatedThumbnailPath = $this->imageHelper->generateThumbnail($originalPhotoResource, $this->photo, $thumbnail);
            $this->albumSource->saveThumbnail($this->photo, $thumbnail, $generatedThumbnailPath);
        }
    }

    public function rotate($angle)
    {
        $imageInfo = array();
        $photoPath = $this->albumSource->getPathToPhoto($this->photo);
        $originalPhotoImage = $this->imageHelper->openImage($photoPath, $imageInfo);
        $originalPhotoImage = $this->imageHelper->rotateImage($originalPhotoImage, intval($angle));
        $this->imageHelper->saveImage($originalPhotoImage, $photoPath, $imageInfo);

        if ($angle == 90 || $angle == 270)
        {
            $width = $this->photo->width;
            $this->photo->width = $this->photo->height;
            $this->photo->height = $width;
        }

        $this->regenerateThumbnails($originalPhotoImage);

        $this->photo->save();
    }

    private function metadataCameraMake(array $exifData)
    {
        if (isset($exifData['Make']))
        {
            return $exifData['Make'];
        }

        return null;
    }

    private function metadataCameraModel(array $exifData)
    {
        if (isset($exifData['Model']))
        {
            return $exifData['Model'];
        }

        return null;
    }

    private function metadataCameraSoftware(array $exifData)
    {
        if (isset($exifData['Software']))
        {
            return $exifData['Software'];
        }

        return null;
    }

    private function metadataDateTime(array $exifData)
    {
        $dateTime = null;
        if (isset($exifData['DateTime']))
        {
            $dateTime = $exifData['DateTime'];
        }

        if (!is_null($dateTime))
        {
            $dateTime = preg_replace('/^([\d]{4}):([\d]{2}):([\d]{2})/', '$1-$2-$3', $dateTime);
        }

        return $dateTime;
    }
}