<?php

namespace App\InvoiceRule;

use App\InvoiceRuleInterface;

use App\Ramcar\TradeInType;

class TradeIn implements InvoiceRuleInterface
{
    public function getID()
    {
        return 'trade-in';
    }

    public function compute($criteria, &$total)
    {
        $items = [];

        // get the entries
        $entries = $criteria->getEntries();
        foreach($entries as $entry)
        {
            $batt = $entry['battery'];
            $qty = $entry['qty'];
            $trade_in_type = null;

            if (isset($entry['trade_in']))
                $trade_in_type = $entry['trade_in'];

            if ($trade_in_type != null)
            {
                $ti_rate = $this->getTradeInRate($batt, $trade_in_type);

                $qty_ti = bcmul($ti_rate, $qty, 2);

                $total['ti_rate'] = bcadd($total['ti_rate'], $qty_ti, 2);
                $total['total_price'] = bcsub($total['total_price'], $qty_ti, 2);

                $price = bcmul($ti_rate, -1, 2);

                $items[] = [
                    'qty' => $qty,
                    'title' => $this->getTitle($batt, $trade_in_type),
                    'price' => $price,
                ];
            }
        }

        return $items;
    }

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

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

    protected function getTradeInRate($battery, $trade_in_type)
    {
        $size = $battery->getSize();

        switch ($trade_in_type)
        {
            case TradeInType::MOTOLITE:
                return $size->getTIPriceMotolite();
            case TradeInType::PREMIUM:
                return $size->getTIPricePremium();
            case TradeInType::OTHER:
                return $size->getTIPriceOther();
        }

        return 0;
    }

    protected function getTitle($battery, $trade_in_type)
    {
        $title = 'Trade-in ' . TradeInType::getName($trade_in_type) . ' ' . $battery->getSize()->getName() . ' battery';

        return $title;
    }
}