<?php

namespace App\Models;

use App\Enumerations\ContentStatuses;
use App\Http\Requests\Request;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Support\Facades\App;
use Illuminate\Support\Facades\DB;
use Mcamara\LaravelLocalization\Facades\LaravelLocalization;
use Modules\Categories\Entities\Category;

/**
 * Class Content
 */
class Content extends Model
{
    public $timestamps = true;
    protected $fillable = [
        'user_id',
        'parent_id',
        'category_id',
        'language',
        'module_handler',
        'published_from',
        'published_to',
        'title_photo',
        'template',
        'is_homepage',
        'title',
        'url',
        'meta_keywords',
        'meta_description',
        'content',
        'module_settings',
        'status'
    ];
    protected $guarded = [];
    protected $subpages = [];
    protected $subpagesInit = false;
    const STATUS_DELETED = 'deleted';
    const STATUS_DRAFT = 'draft';
    const STATUS_PROTECTED = 'protected';
    const STATUS_PUBLIC = 'public';
    /**
     * @var File
     */
    private $file;

    public function __construct(array $attributes = [])
    {
        parent::__construct($attributes);

        $this->file = App::make(File::class);
    }

    /**
     * Getter for query with setup filter for non-deleted and non-draft pages
     */
    public function getPageQuery()
    {
        return Content::where('status', '!=', Content::STATUS_DELETED)
                      ->where('status', '!=', Content::STATUS_DRAFT);
    }

    /**
     * Getter for homepage content page
     * @return Content
     */
    public function getHomepage()
    {
        return $this->getPageQuery()
                    ->where('language', LaravelLocalization::getCurrentLocale())
                    ->where('is_homepage', 1)
                    ->first();
    }

    /**
     * Getter for any page specified by its url.
     *
     * @param $url
     *
     * @return Content
     */
    public function getByURL($url)
    {
        return $this->getPageQuery()
                    ->where('url', $url)
                    ->where('language', LaravelLocalization::getCurrentLocale())
                    ->first();
    }

    /**
     * Get list of all subpages
     *
     * @return \Illuminate\Database\Eloquent\Relations\HasMany
     */
    public function subpages()
    {
        if (!$this->subpagesInit) {
            $this->subpages = $this->getPageQuery()
                                   ->where('parent_id', $this->id)
                                   ->where('language', LaravelLocalization::getCurrentLocale())
                                   ->get();

            // convert JSON settings into stdClass
            foreach ($this->subpages as $subpage) {
                $subpage->module_settings = json_decode($subpage->module_settings);
            }

            $this->subpagesInit = true;
        }

        return $this->subpages;
    }

    /**
     * Is current content draft?
     *
     * @return bool
     */
    public function isDraft()
    {
        return $this->status == self::STATUS_DRAFT;
    }

    /**
     * Is current content visible for all visitors?
     *
     * @return bool
     */
    public function isPublic()
    {
        return $this->status == self::STATUS_PUBLIC;
    }

    /**
     * Is current content visible only for logged users?
     *
     * @return bool
     */
    public function isProtected()
    {
        return $this->status == self::STATUS_PROTECTED;
    }

    /**
     * Is current content visible for logged user OR for everyone?
     *
     * @return bool
     */
    public function isVisible()
    {
        return $this->isPublic() || $this->isProtected();
    }

    /**
     * Returns list of all root pages - those pages, which parent_id is null
     *
     * @return mixed
     */
    public function rootPages()
    {
        $rootPages = $this->getPageQuery()
                          ->where('language', LaravelLocalization::getCurrentLocale())
                          ->where('parent_id', null);

        if ($this->id) {
            $rootPages = $rootPages->where('id', '!=', $this->id);
        }

        return $rootPages->get();
    }

    /**
     * Getter for overview of all content pages.
     * These content pages may be filtered by using some handler
     *
     * @param bool $handler
     * @param bool $status
     * @param bool $joinAuthor
     *
     * @return
     */
    public function getOverview($handler = false, $status = false, $joinAuthor = false, $joinParent = false)
    {
        $query = DB::table('contents')
                   ->select('contents.*', 'modules.name AS module_name')
                   ->where('contents.status', '<>', self::STATUS_DELETED)
                   ->where('contents.language', LaravelLocalization::getCurrentLocale())
                   ->join('modules', 'modules.handler', '=', 'contents.module_handler')
                   ->orderBy('created_at', 'DESC');

        // filter results using handler
        if ($handler) {
            $query = $query->where('contents.module_handler', $handler);
        }

        // join user email and user name to results when needed
        if ($joinAuthor) {
            $query = $query->join('users', 'users.id', '=', 'contents.user_id')
                           ->addSelect(DB::raw('COALESCE(users.name, users.email) AS author_name'))
                           ->addSelect('users.email AS author_email');
        }

        if ($joinParent) {
            $query = $query->leftJoin('contents as parent', 'parent.id', '=', 'contents.parent_id')
                           ->addSelect('parent.title AS parent_title')
                           ->addSelect('parent.url AS parent_url');
        }

        // add filtering by status
        if (in_array($status, ContentStatuses::getSimple())) {
            $query = $query->where('contents.status', $status);
        }

        return $query;
    }

    /**
     * Updates current model with information about changed columns
     *
     * @param array  $fields
     * @param array  $request
     * @param string $revisionId
     *
     * @return array revisionID and number of changed columns
     */
    public function updateWithHistory(array $fields, array $request, $revisionId = null)
    {
        if (!$revisionId) {
            $revisionId = uniqid();
        }

        $changed = 0;

        foreach ($fields as $fieldDB => $fieldRequest) {
            // ignore non-existing fields
            if (!isset($request[$fieldRequest]) && !is_null($request[$fieldRequest])) {
                continue;
            }

            // if module settings is still JSON, decode it to normal stdClass
            if (is_string($this->module_settings)) {
                $this->module_settings = json_decode($this->module_settings);
            }

            // are we editing common settings, or module-specific settings?
            if (!in_array($fieldDB, $this->fillable)) {
                // this field is not part of "core" content - probably it will be module settings
                $commonField = false;
                $fieldValue = isset($this->module_settings->$fieldDB) ? $this->module_settings->$fieldDB : null;
            } else {
                $commonField = true;
                $fieldValue = $this->$fieldDB;
            }

            // remove any whitespaces around real content
            if (!is_null($request[$fieldRequest])) {
                $request[$fieldRequest] = trim($request[$fieldRequest]);
            }

            if (trim($fieldValue) != $request[$fieldRequest]) {

                $this->saveHistory($revisionId, $fieldRequest, $fieldValue, $request);

                // save change into database
                if ($commonField) {
                    $this->$fieldDB = $request[$fieldRequest];
                } else {
                    $this->module_settings->$fieldDB = $request[$fieldRequest];
                }

                $changed++;
            }
        }

        // make JSON from stdClass
        if (!is_string($this->module_settings)) {
            $this->module_settings = json_encode($this->module_settings);
        }

        $this->save();

        return [$revisionId, $changed];
    }

    /**
     * Upload and set some image as title photo
     *
     * @param Request $request
     */
    public function uploadTitlePhoto(Request $request)
    {
        if ($request->hasFile('titlePhoto')) {
            $file = $this->file->upload($request->file('titlePhoto'), $request);

            $this->title_photo = $file['filename'];
        }
    }

    /**
     * Upload and assign files to newly created content page
     *
     * @param Request $request
     * @param null    $revisionId
     *
     * @return int
     */
    public function uploadRelatedFiles(Request $request, $revisionId = null)
    {
        $files = $request->all()['files'];
        $changed = 0;

        // check if any file was removed
        if ($revisionId) {
            $changed += $this->removeRelatedFiles($revisionId, $request);
        }

        // allow uploading only on created pages
        if (!$this->id || !$files[0]) {
            return $changed;
        }

        // find or create new directory for files assigned to content
        $directory = Directory::firstOrCreate([
                                                  'name'   => '.content_files',
                                                  'hidden' => true
                                              ]);
        $request->directoryId = $directory->id;

        foreach ($files as $file) {
            if (!$file) {
                continue;
            }
            $uploaded = $this->file->upload($file, $request);

            // add assignement
            ContentHasFile::create([
                                       'file_id'    => $uploaded['id'],
                                       'content_id' => $this->id
                                   ]);

            if ($revisionId) {
                $this->saveHistory($revisionId, 'file', null, ['file' => $uploaded['file']->getClientOriginalName()]);
            }

            $changed++;
        }

        return $changed;
    }

    /**
     * Delete files from association
     *
     * @param $revisionId
     * @param $request
     *
     * @return int
     */
    private function removeRelatedFiles($revisionId, $request)
    {
        $files = array_keys((array)$request->keepAssigned);

        $allFiles = $this->files()
                         ->whereNotIn('id', $files)
                         ->get();

        foreach ($allFiles as $file) {
            $this->saveHistory($revisionId, 'file', $file->original_filename, ['file' => null]);

            ContentHasFile::where('content_id', $this->id)
                          ->where('file_id', $file->id)
                          ->delete();
        }

        return count($allFiles);
    }

    /**
     * Mark relationship with its historical records
     *
     * @return \Illuminate\Database\Eloquent\Relations\HasMany
     */
    public function history()
    {
        return $this->hasMany('App\Models\ContentHistory');
    }

    /**
     * Mark relationship with users table
     *
     * @return \Illuminate\Database\Eloquent\Relations\BelongsTo
     */
    public function author()
    {
        return $this->belongsTo('App\Models\User', 'user_id');
    }

    /**
     * Related files to content page
     *
     * @return \Illuminate\Database\Eloquent\Relations\BelongsToMany
     */
    public function files()
    {
        return $this->belongsToMany(File::class, 'contents_has_files');
    }

    public function category()
    {
        return $this->belongsTo(Category::class);
    }

    /**
     * Save history entry into database
     *
     * @param $revisionId
     * @param $fieldRequest
     * @param $fieldValue
     * @param $request
     */
    private function saveHistory($revisionId, $fieldRequest, $fieldValue, $request)
    { // setup history object
        $history = [
            'user_id'    => \Auth::user()->id,
            'content_id' => $this->id,
            'edit_batch' => $revisionId,
            'column'     => $fieldRequest,
            'old_value'  => $fieldValue,
            'new_value'  => $request[$fieldRequest]
        ];

        // save history
        ContentHistory::create($history);
    }
}