<?php

namespace Zoomyboy\Social\Classes;

use Carbon\Carbon;
use GuzzleHttp\Client;
use Event;
use Media\Classes\MediaLibrary;
use Zoomyboy\Social\Models\Page;
use Zoomyboy\Social\Models\Post;
use Zoomyboy\Social\Models\Setting;

class FacebookSyncService {

    private static $baseUri = 'https://graph.facebook.com';
    protected $client;
    protected $page;
    protected $token;
    protected $version = 'v11.0';
    protected $media;

    public static function page($page, $token) {
        return new static($page, $token);
    }

    private function __construct(Page $page) {
        $this->media = MediaLibrary::instance();
        $this->page = $page;
        $this->token = $page->access_token;
        $this->client = new Client([ 'http_errors' => false, 'base_uri' => static::$baseUri ]);
    }

    public function clear() {
        $this->page->delete();
    }

    public function posts(): array
    {
        return $this->get(
            "{$this->page->remote_id}/published_posts",
            ['fields' => 'id,created_time,full_picture,message,attachments'],
            'data',
        );
    }

    public function saveUrl(string $source, ?string $filename = null): string
    {
        $filename = $filename ?: pathinfo(parse_url($source, PHP_URL_PATH), PATHINFO_BASENAME);
        $file = $this->page->mediaPath.$filename;

        if (!$this->media->exists($file)) {
            $this->media->put($file, file_get_contents($source));
            Event::fire('media.file.upload', [null, $file, null]);
        }

        return $file;
    }

    public function saveCover() {
        $cover = $this->get($this->page->remote_id, ['fields' => 'cover'], 'cover');
        $this->page->update([ 'cover' => $this->saveUrl($cover['source']) ]);
    }

    public function saveAttachments(Post $post, $data) {
        foreach($data as $i => $attachment) {
            $fid = null;

            switch($attachment['type']) {
                case 'photo':
                case 'video_inline':
                    $payload = [ 'href' => $this->saveUrl(data_get($attachment, 'media.image.src')) ]; break;
                case 'share':
                case 'event':
                    $fid = $post->id.'-attachment-'.$i;
                    if (!data_get($attachment, 'media.image.src')) {
                        continue 2;
                    }
                    $payload = [ 'href' => $this->saveUrl(data_get($attachment, 'media.image.src'), $fid.'.jpg') ];
                    break;
                case 'album':
                    $payload = [ 'href' => $this->saveUrl(data_get($attachment, 'subattachments.data.0.media.image.src')) ]; break;
                case 'multi_share':
                    $payload = [ 'href' => $this->saveUrl(data_get($attachment, 'subattachments.data.0.media.image.src')) ]; break;
                case 'native_templates': continue 2;
                default:
                    throw new \Exception('I dont know how to parse attachment of type '.$attachment['type']);
            }

            $fid = $fid ?: data_get($attachment, 'target.id', '');
            $post->attachments()->updateOrCreate(['facebook_id' => $fid], array_merge($payload, [
                'facebook_id' => $fid,
                'type' => $attachment['type'],
            ]));
        }
    }

    public function sync(): void
    {
        $this->saveCover();

        foreach ($this->posts() as $post) {
            if (!data_get($post, 'message')) {
                continue;
            }

            if (!data_get($post, 'attachments')) {
                continue;
            }

            $payload = [
                'message' => $post['message'],
                'facebook_id' => $post['id'],
                'href' => data_get($post, 'attachments.data.0.target.url'),
                'created_at' => Carbon::parse($post['created_time']),
            ];

            $existing = $this->page->posts()->where('facebook_id', $post['id'])->first();

            if ($existing) {
                $existing->update($payload);
            } else {
                $existing = $this->page->posts()->create($payload);
            }

            $this->saveAttachments($existing, data_get($post, 'attachments.data'));
        }

        if (!is_numeric(Setting::get('max_posts'))) {
            return;
        }

        while ($this->page->posts()->get()->count() > 0 && $this->page->posts()->get()->count() > Setting::get('max_posts')) {
            $this->page->posts()->orderBy('created_at')->first()->delete();
        }
    }

    // -------------------------------- static api ---------------------------------
    // *****************************************************************************
    public static function clearAll(): void
    {
        foreach (Page::where('type', 'facebook')->get() as $page) {
            $service = new static($page);
            $service->clear();
        }
    }

    public static function syncAll(): void
    {
        foreach (Page::where('type', 'facebook')->get() as $page) {
            $service = new static($page);
            $service->sync();
        }
    }

    // -------------------------------- Guzzle Api ---------------------------------
    // *****************************************************************************
    private function get(string $url, array $query = [], ?string $return = null): array
    {
        $response = $this->client->get("/{$this->version}/$url", [
            'query' => array_merge($query, ['access_token' => $this->token]),
        ]);

        $data = json_decode((string) $response->getBody(), true);

        return $return === null
            ? $data
            : data_get($data, $return);
    }

}