<?php

/* This is a mashup of FlickrExploreBridge by sebsauvage and FlickrTagBridge
 * by erwang, providing the functionality of both in one.
 */
class FlickrBridge extends BridgeAbstract
{
    const MAINTAINER = 'logmanoriginal';
    const NAME = 'Flickr Bridge';
    const URI = 'https://www.flickr.com/';
    const CACHE_TIMEOUT = 21600; // 6 hours
    const DESCRIPTION = 'Returns images from Flickr';

    const PARAMETERS = [
        'Explore' => [],
        'By keyword' => [
            'q' => [
                'name' => 'Keyword',
                'type' => 'text',
                'required' => true,
                'title' => 'Insert keyword',
                'exampleValue' => 'bird'
            ],
            'media' => [
                'name' => 'Media',
                'type' => 'list',
                'values' => [
                    'All (Photos & videos)' => 'all',
                    'Photos' => 'photos',
                    'Videos' => 'videos',
                ],
                'defaultValue' => 'all',
            ],
            'sort' => [
                'name' => 'Sort By',
                'type' => 'list',
                'values' => [
                    'Relevance' => 'relevance',
                    'Date uploaded' => 'date-posted-desc',
                    'Date taken' => 'date-taken-desc',
                    'Interesting' => 'interestingness-desc',
                ],
                'defaultValue' => 'relevance',
            ]
        ],
        'By username' => [
            'u' => [
                'name' => 'Username',
                'type' => 'text',
                'required' => true,
                'title' => 'Insert username (as shown in the address bar)',
                'exampleValue' => 'flickr'
            ],
            'content' => [
                'name' => 'Content',
                'type' => 'list',
                'values' => [
                    'Uploads' => 'uploads',
                    'Favorites' => 'faves',
                ],
                'defaultValue' => 'uploads',
            ],
            'media' => [
                'name' => 'Media',
                'type' => 'list',
                'values' => [
                    'All (Photos & videos)' => 'all',
                    'Photos' => 'photos',
                    'Videos' => 'videos',
                ],
                'defaultValue' => 'all',
            ],
            'sort' => [
                'name' => 'Sort By',
                'type' => 'list',
                'values' => [
                    'Relevance' => 'relevance',
                    'Date uploaded' => 'date-posted-desc',
                    'Date taken' => 'date-taken-desc',
                    'Interesting' => 'interestingness-desc',
                ],
                'defaultValue' => 'date-posted-desc',
            ]
        ]
    ];

    private $username = '';

    public function collectData()
    {
        switch ($this->queriedContext) {
            case 'Explore':
                $filter = 'photo-lite-models';
                $html = getSimpleHTMLDOM($this->getURI());
                break;

            case 'By keyword':
                $filter = 'photo-lite-models';
                $html = getSimpleHTMLDOM($this->getURI());
                break;

            case 'By username':
                //$filter = 'photo-models';
                $filter = 'photo-lite-models';
                $html = getSimpleHTMLDOM($this->getURI());

                $this->username = $this->getInput('u');

                if ($html->find('span.search-pill-name', 0)) {
                    $this->username = $html->find('span.search-pill-name', 0)->plaintext;
                }
                break;

            default:
                returnClientError('Invalid context: ' . $this->queriedContext);
        }

        $model_json = $this->extractJsonModel($html);
        $photo_models = $this->getPhotoModels($model_json, $filter);

        foreach ($photo_models as $model) {
            $item = [];

            /* Author name depends on scope. On a keyword search the
            * author is part of the picture data. On a username search
            * the author is part of the owner data.
            */
            if (array_key_exists('username', $model)) {
                $item['author'] = urldecode($model['username']);
            } elseif (array_key_exists('owner', reset($model_json)[0])) {
                $item['author'] = urldecode(reset($model_json)[0]['owner']['username']);
            }

            $item['title'] = urldecode((array_key_exists('title', $model) ? $model['title'] : 'Untitled'));
            $item['uri'] = self::URI . 'photo.gne?id=' . $model['id'];

            $description = (array_key_exists('description', $model) ? $model['description'] : '');

            $item['content'] = '<a href="'
            . $item['uri']
            . '"><img src="'
            . $this->extractContentImage($model)
            . '" style="max-width: 640px; max-height: 480px;"/></a><br><p>'
            . urldecode($description)
            . '</p>';

            $item['enclosures'] = $this->extractEnclosures($model);

            $this->items[] = $item;
        }
    }

    public function getURI()
    {
        switch ($this->queriedContext) {
            case 'Explore':
                return self::URI . 'explore';
                break;
            case 'By keyword':
                return self::URI . 'search/?q=' . urlencode($this->getInput('q'))
                    . '&sort=' . $this->getInput('sort') . '&media=' . $this->getInput('media');
                break;
            case 'By username':
                $uri = self::URI . 'search/?user_id=' . urlencode($this->getInput('u'))
                    . '&sort=date-posted-desc&media=' . $this->getInput('media');

                if ($this->getInput('content') === 'faves') {
                    return $uri . '&faves=1';
                }

                return $uri;
                break;

            default:
                return parent::getURI();
        }
    }

    public function getName()
    {
        switch ($this->queriedContext) {
            case 'Explore':
                return 'Explore - ' . self::NAME;
                break;
            case 'By keyword':
                return $this->getInput('q') . ' - keyword - ' . self::NAME;
                break;
            case 'By username':
                if ($this->getInput('content') === 'faves') {
                    return $this->username . ' - favorites - ' . self::NAME;
                }

                return $this->username . ' - ' . self::NAME;
                break;

            default:
                return parent::getName();
        }

        return parent::getName();
    }

    private function extractJsonModel($html)
    {
        // Find SCRIPT containing JSON data
        $model = $html->find('.modelExport', 0);
        $model_text = $model->innertext;

        // Find start and end of JSON data
        $start = strpos($model_text, 'modelExport:') + strlen('modelExport:');
        $end = strpos($model_text, 'auth:') - strlen('auth:');

        // Extract JSON data, remove trailing comma
        $model_text = trim(substr($model_text, $start, $end - $start));
        $model_text = substr($model_text, 0, strlen($model_text) - 1);

        return json_decode($model_text, true);
    }

    private function getPhotoModels($json, $filter)
    {
        // The JSON model contains a "legend" array, where each element contains
        // the path to an element in the "main" object
        $photo_models = [];

        foreach ($json['legend'] as $legend) {
            $photo_model = $json['main'];

            foreach ($legend as $element) { // Traverse tree
                $photo_model = $photo_model[$element];
            }

            // We are only interested in content
            if ($photo_model['_flickrModelRegistry'] === $filter) {
                $photo_models[] = $photo_model;
            }
        }

        return $photo_models;
    }

    private function extractEnclosures($model)
    {
        $areas = [];

        foreach ($model['sizes'] as $size) {
            $areas[$size['width'] * $size['height']] = $size['url'];
        }

        return [$this->fixURL(max($areas))];
    }

    private function extractContentImage($model)
    {
        $areas = [];
        $limit = 320 * 240;

        foreach ($model['sizes'] as $size) {
            $image_area = $size['width'] * $size['height'];

            if ($image_area >= $limit) {
                $areas[$image_area] = $size['url'];
            }
        }

        return $this->fixURL(min($areas));
    }

    private function fixURL($url)
    {
        // For some reason the image URLs don't include the protocol (https)
        if (strpos($url, '//') === 0) {
            $url = 'https:' . $url;
        }

        return $url;
    }
}