pollux/app/Person.php

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;
use Carbon\Carbon;
use App\MemberState;

class Person extends Model
{
    /*
     * Return true, if the person is active member, return false otherwise.
     *
     * @return boolean
     */
    public function isActiveMember()
    {
        $latest = $this->hasMany('\App\MemberState')
                       ->orderBy('joining_date', 'desc')
                       ->first();
    
        if (is_null($latest)) {
            return false;
        } else {
            return is_null($latest['leaving_date']);
        }
    }

    /*
     * Return a collection of all persons which are active members.
     *
     * @return Illuminate\Database\Eloquent\Collection
     */
    public static function active()
    {
        return Person::join('member_states', 'people.id', '=', 'member_states.person_id')
                     ->where('member_states.leaving_date', null)
                     ->select('person_id as id', 'title', 'name_or_company',
                              'surname', 'date_of_birth', 'city', 'street',
                              'postal_code', 'email', 'mobile', 'phone',
                              'people.created_at', 'people.updated_at')
                     ->get();
    }

    /*
     * Return the last date since when the person is an active member.
     * 
     * @return Carbon\Carbon
     */
    public function activeSince()
    {
        $latest = $this->hasMany('\App\MemberState')
                       ->orderBy('joining_date', 'desc')
                       ->first();
    
        return Carbon::parse($latest['joining_date']);
    }

    /*
     * Returns the active time of the person until now in years.
     *
     * @return float
     */
    public function activeTime()
    {
        $activeTimes = $this->hasMany('\App\MemberState')->get();
        
        $diff = 0;

        foreach ($activeTimes as $period) {
            $start = Carbon::parse($period['joining_date']);
            $end = is_null($period['leaving_date']) ?
                   Carbon::now() :
                   Carbon::parse($period['leaving_date']);
            
            $diffYears = Carbon::parse($start)->diffInYears($end);
            $diffDays = Carbon::parse($start)->diffInDays($end);

            $diff += $diffYears + $diffDays / 365 - $diffYears;
        }

        return $diff;
    }
}