<?php
/**
 * Invoice Ninja (https://invoiceninja.com).
 *
 * @link https://github.com/invoiceninja/invoiceninja source repository
 *
 * @copyright Copyright (c) 2021. Invoice Ninja LLC (https://invoiceninja.com)
 *
 * @license https://www.elastic.co/licensing/elastic-license
 */

namespace App\Helpers\Invoice;

use App\Models\Invoice;
use App\Models\RecurringInvoice;
use Carbon\Exceptions\InvalidFormatException;
use Exception;
use Illuminate\Contracts\Container\BindingResolutionException;
use Illuminate\Support\Carbon;

class ProRata
{

    /**
     * @param float $amount 
     * @param Carbon $from_date 
     * @param Carbon $to_date 
     * @param int $frequency 
     * @return float 
     */
    public function refund(float $amount, Carbon $from_date, Carbon $to_date, int $frequency) :float
    {
        $days = $from_date->diffInDays($to_date);
        $days_in_frequency = $this->getDaysInFrequency($frequency);

        return round( (($days/$days_in_frequency) * $amount),2);
    }


    /**
     * Prepares the line items of an invoice
     * to be pro rata refunded.
     * 
     * @param Invoice $invoice 
     * @param bool $is_credit 
     * @return array 
     * @throws Exception 
     */
    public function refundItems(Invoice $invoice, $is_credit = false) :array
    {
        if(!$invoice)
            return [];

        $recurring_invoice = RecurringInvoice::find($invoice->recurring_id)->first();

        if(!$recurring_invoice)
            throw new \Exception("Invoice isn't attached to a recurring invoice");

        /* depending on whether we are creating an invoice or a credit*/
        $multiplier = $is_credit ? 1 : -1;

        $start_date = Carbon::parse($invoice->date);

        $line_items = [];

        foreach($invoice->line_items as $item)
        {

            if($item->product_key != ctrans('texts.refund'))
            {
                $item->quantity = 1;
                $item->cost = $this->refund($item->cost*$multiplier, $start_date, now(), $recurring_invoice->frequency_id);
                $item->product_key = ctrans('texts.refund');
                $item->notes = ctrans('texts.refund') . ": ". $item->notes;

                $line_items[] = $item;

            }
        }

        return $line_items;

    }


    private function getDaysInFrequency($frequency)
    {

        switch ($frequency) {
            case RecurringInvoice::FREQUENCY_DAILY:
                return 1;
            case RecurringInvoice::FREQUENCY_WEEKLY:
                return 7;
            case RecurringInvoice::FREQUENCY_TWO_WEEKS:
                return 14;
            case RecurringInvoice::FREQUENCY_FOUR_WEEKS:
                return now()->diffInDays(now()->addWeeks(4));
            case RecurringInvoice::FREQUENCY_MONTHLY:
                return now()->diffInDays(now()->addMonthNoOverflow());
            case RecurringInvoice::FREQUENCY_TWO_MONTHS:
                return now()->diffInDays(now()->addMonthNoOverflow(2));
            case RecurringInvoice::FREQUENCY_THREE_MONTHS:
                return now()->diffInDays(now()->addMonthNoOverflow(3));
            case RecurringInvoice::FREQUENCY_FOUR_MONTHS:
                return now()->diffInDays(now()->addMonthNoOverflow(4));
            case RecurringInvoice::FREQUENCY_SIX_MONTHS:
                return now()->diffInDays(now()->addMonthNoOverflow(6));
            case RecurringInvoice::FREQUENCY_ANNUALLY:
                return now()->diffInDays(now()->addYear());
            case RecurringInvoice::FREQUENCY_TWO_YEARS:
                return now()->diffInDays(now()->addYears(2));
            case RecurringInvoice::FREQUENCY_THREE_YEARS:
                return now()->diffInDays(now()->addYears(3));
            default:
                return 0;
        }

    }

}