<?php

namespace App\InvoiceRule;

use App\InvoiceRuleInterface;

use App\Ramcar\FuelType;
use App\Ramcar\ServiceType;

class Fuel implements InvoiceRuleInterface
{   
    public function getID()
    {   
        return 'fuel';
    }

    public function compute($criteria, &$total) 
    {
        $stype = $criteria->getServiceType();

        $items = [];
        
        if ($stype == $this->getID())
        {
            // check if customer vehicle has a motolite battery
            $cv = $criteria->getCustomerVehicle();
            if ($cv->hasMotoliteBattery())
                $fee = 0;
            else
                $fee = $this->getServiceTypeFee();

            $ftype = $cv->getFuelType();

            // add the service fee to items
            $qty = 1;
            $items[] = [
                'service_type' => $this->getID(),
                'qty' => $qty,
                'title' => $this->getServiceTitle($ftype),
                'price' => $fee,
            ];
 
            $qty_fee = bcmul($qty, $fee, 2);
            $total_price = $qty_fee;

            switch ($ftype)
            {
                case FuelType::GAS:
                case FuelType::DIESEL:
                    $qty = 1;
                    $price = $this->getFuelFee($ftype);
                    $items[] = [
                        'service_type' => $this->getID(),
                        'qty' => $qty,
                        'title' => $this->getTitle($ftype),
                        'price' => $price,
                    ];

                    $qty_price = bcmul($price, $qty, 2);
                    $total_price = bcadd($total_price, $qty_price, 2);

                    break;
                default:
                    $qty = 1;
                    $price = 0;
                    $items[] = [
                        'service_type' => $this->getID(),
                        'qty' => $qty,
                        'title' => $this->getTitle('Unknown'),
                        'price' => $price,
                    ];

                    $qty_price = bcmul($price, $qty, 2);
                    $total_price = bcadd($total_price, $qty_price, 2);

                    break;    
            }

            $total['total_price'] = bcadd($total['total_price'], $total_price, 2);
        }

        return $items;
    }

    public function getServiceTypeFee()
    {   
        // TODO: we need to to put this somewhere like in .env
        // so that if any changes are to be made, we just edit the file
        // instead of the code
        return 300;
    }

    public function getFuelFee($fuel_type)
    {
        // TODO: we need to to put this somewhere like in .env
        // so that if any changes are to be made, we just edit the file
        // instead of the code
        if ($fuel_type == FuelType::GAS)
        {
            // gas fuel fee
            return 320;
        }
        else
        {
            // diesel fuel fee
            return 340;
        }
    }

    public function validatePromo($criteria, $promo_id)
    {
        return false;
    }

    public function validateInvoiceItems($criteria, $invoice_items)
    {
        return null;
    }

    protected function getTitle($fuel_type)
    {
        $title = '4L - ' . ucfirst($fuel_type);

        return $title;
    }

    protected function getServiceTitle($fuel_type)
    {
        $title = 'Service - ' . ServiceType::getName(ServiceType::EMERGENCY_REFUEL);

        return $title;
    }
}