<?php

namespace App\Traits;

use Illuminate\Database\Eloquent\Builder;

trait FullTextSearch
{
    /**
     * Replaces spaces with full text search wildcards
     *
     * @param string $term
     * @return string
     */
    protected function fullTextWildcards($term)
    {
        // removing symbols used by MySQL
        $reservedSymbols = ['-', '+', '<', '>', '@', '(', ')', '~'];
        $term = str_replace($reservedSymbols, '', $term);

        $words = explode(' ', $term);

        foreach($words as $key => $word) {
            /*
             * applying + operator (required word) only big words
             * because smaller ones are not indexed by mysql
             */
            if(strlen($word) >= 3) {
                $words[$key] = '+' . $word . '*';
            }
        }

        $searchTerm = implode(' ', $words);

        return $searchTerm;
    }

    /**
     * Scope a query that matches a full text search of term.
     *
     * @param \Illuminate\Database\Eloquent\Builder $query
     * @param string $term
     * @return \Illuminate\Database\Eloquent\Builder
     */
    public function scopeSearch($query, $term)
    {
        $modelPlural = $this->getTable();
        $modelSingular = str_singular($modelPlural);
        $columns = implode(',',$this->searchable);

        return $query->join($modelSingular . '_translations', $modelPlural . '.id', '=', $modelSingular . '_translations.' . $modelSingular . '_id')
        ->select($modelPlural . '.*')
        ->where($modelSingular . '_translations.locale', app()->getLocale())
        ->whereRaw("MATCH ({$columns}) AGAINST (? IN BOOLEAN MODE)", [$this->fullTextWildcards($term)]); 
    }
}