<?php

namespace App\Service;

use App\Ramcar\InvoiceCriteria;
use App\Ramcar\TradeInType;

use App\Entity\Invoice;
use App\Entity\InvoiceItem;
use App\Entity\User;

use Doctrine\Common\Util\Debug;

class InvoiceCreator
{
    const VAT_RATE              = 0.12;
    const TIRATE_MOTOLITE       = 200.00;
    const TIRATE_OTHER          = 100.00;

    // creates invoice based on the criteria sent
    public function __construct()
    {
    }

    public function getVATAmount($price)
    {
        $vat_ex_price = $this->getVATExclusivePrice($price);
        return round($vat_ex_price * self::VAT_RATE, 2);
    }

    public function getVATExclusivePrice($price)
    {
        return round($price / (1 + self::VAT_RATE), 2);
    }

    public function getTradeInRate($trade_in)
    {
        if ($trade_in == 'motolite')
            return self::TIRATE_MOTOLITE;

        return self::TIRATE_OTHER;
    }

    protected function processBatteries(&$total, InvoiceCriteria $criteria, Invoice $invoice)
    {
        // get batteries
        $batts = $criteria->getBatteries();

        // consolidate batteries
        $con_batts = [];
        foreach ($batts as $batt)
        {
            $batt_id = $batt->getID();

            // initialize
            if (!isset($con_batts[$batt_id]))
                $con_batts[$batt->getID()] = [
                    'batt' => $batt,
                    'qty' => 0
                ];

            // increment quantity
            $con_batts[$batt_id]['qty']++;
        }

        // process batteries
        foreach ($con_batts as $con_data)
        {
            $batt = $con_data['batt'];
            $qty = $con_data['qty'];

            $sell_price = $batt->getSellingPrice();
            $vat = $this->getVATAmount($sell_price);
            // $vat_ex_price = $this->getVATExclusivePrice($sell_price);

            $total['sell_price'] += $sell_price * $qty;
            $total['vat'] += $vat * $qty;
            $total['vat_ex_price'] += ($sell_price - $vat) * $qty;

            $total['total_price'] += $sell_price * $qty;

            // add item
            $item = new InvoiceItem();
            $item->setInvoice($invoice)
                ->setTitle($batt->getModel()->getName() . ' ' . $batt->getSize()->getName())
                ->setQuantity($qty)
                ->setPrice($sell_price);

            $invoice->addItem($item);
        }
    }

    protected function processTradeIns(&$total, InvoiceCriteria $criteria, Invoice $invoice)
    {
        // get trade-ins
        $trade_ins = $criteria->getTradeIns();

        // consolidate
        $con_tis = [];
        foreach ($trade_ins as $ti)
        {
            if (!isset($con_tis[$ti]))
                $con_tis[$ti] = 0;

            $con_tis[$ti]++;
        }

        // process
        foreach ($con_tis as $ti => $qty)
        {
            $ti_rate = $this->getTradeInRate($ti);

            $total['ti_rate'] += $ti_rate * $qty;
            $total['total_price'] -= $ti_rate * $qty;

            // add item
            $item = new InvoiceItem();
            $item->setInvoice($invoice)
                ->setTitle('Trade-in ' . TradeInType::getName($ti) . ' battery')
                ->setQuantity($qty)
                ->setPrice($ti_rate * -1);

            $invoice->addItem($item);
        }
    }

    protected function processDiscount(&$total, InvoiceCriteria $criteria, Invoice $invoice)
    {
    }

    public function processCriteria(InvoiceCriteria $criteria)
    {
        $invoice = new Invoice();

        $total = [
            'sell_price' => 0.0,
            'vat' => 0.0,
            'vat_ex_price' => 0.0,
            'ti_rate' => 0.0,
            'total_price' => 0.0,
        ];

        $this->processBatteries($total, $criteria, $invoice);
        $this->processTradeIns($total, $criteria, $invoice);
        $this->processDiscount($total, $criteria, $invoice);

        // TODO: check if any promo is applied
        // apply discounts
        $promos = $criteria->getPromos();

        $invoice->setTotalPrice($total['total_price'])
            ->setVATExclusivePrice($total['vat_ex_price'])
            ->setVAT($total['vat'])
            ->setTradeIn($total['ti_rate']);


        // dump
        //Debug::dump($invoice, 1);

        return $invoice;
    }
}