<?php

namespace App\Services;

use App\Models\Logger;
use App\Models\PaymentReminder;
use App\Models\ShoppingPayment;
use App\Mail\PaymentReminderEmail;
use App\Services\Util;
use Carbon\Carbon;
use Illuminate\Support\Facades\Mail;

class PaymentReminderService
{
    protected $clearingtypes = [];

    public function __construct()
    {
        $this->clearingtypes = PaymentReminder::returnClearingtypes();
    }

    /**
     * Erstellt einen Log-Eintrag für Payment Reminder Aktivitäten
     */
    private function createLog($action, $message, $model = null, $modelId = null, $level = 2)
    {
        return Logger::create([
            'user_id' => null, // System-Aktion
            'model_id' => $modelId,
            'model' => $model,
            'action' => $action,
            'channel' => 'payment_reminder',
            'message' => $message,
            'level' => $level
        ]);
    }

    /**
     * Hole alle aktiven Intervalle für Zahlungserinnerungen
     */
    public function getActiveIntervals()
    {
        $intervals = [];
        $payment_reminders = PaymentReminder::where('active', true)->get();

        foreach($payment_reminders as $reminder) {
            $intervals[$reminder->clearingtype] = $reminder->interval;
        }

        return $intervals;
    }

    /**
     * Hole alle offenen Zahlungen für einen bestimmten clearingtype
     */
    public function getOpenPaymentsForClearingType($clearingtype, $interval)
    {
        $date = Carbon::now()->subDays($interval);

        $payments = ShoppingPayment::join('shopping_orders', 'shopping_payments.shopping_order_id', '=', 'shopping_orders.id')
            ->where('shopping_payments.clearingtype', '=', $clearingtype)
            ->where('shopping_payments.txaction', '=', 'open')
            ->where('shopping_payments.mode', '=', 'live')
            ->where('shopping_payments.created_at', '<', $date)
            ->where('shopping_payments.amount', '>', 0)
            ->whereNull('shopping_orders.deleted_at')
            ->whereIn('shopping_payments.id', function($query) use ($clearingtype, $date) {
                $query->selectRaw('MAX(shopping_payments.id)')
                    ->from('shopping_payments')
                    ->join('shopping_orders', 'shopping_payments.shopping_order_id', '=', 'shopping_orders.id')
                    ->where('shopping_payments.clearingtype', '=', $clearingtype)
                    ->where('shopping_payments.txaction', '=', 'open')
                    ->where('shopping_payments.mode', '=', 'live')
                    ->where('shopping_payments.created_at', '<', $date)
                    ->where('shopping_payments.amount', '>', 0)
                    ->whereNull('shopping_orders.deleted_at')
                    ->groupBy('shopping_payments.shopping_order_id');
            })
            ->select('shopping_payments.*')
            ->get();


        return $payments;
    }

    /**
     * Hole alle offenen Zahlungen für alle clearingtypes
     */
    public function getAllOpenPayments()
    {
        $intervals = $this->getActiveIntervals();
        $results = [];

        foreach($intervals as $clearingtype => $interval){
            $date = Carbon::now()->subDays($interval);
            $payments = $this->getOpenPaymentsForClearingType($clearingtype, $interval);
            
            $results[$clearingtype] = [
                'interval' => $interval,
                'date_limit' => $date,
                'payments' => $payments,
                'count' => $payments->count()
            ];
        }

        return $results;
    }

    /**
     * Hole detaillierte Daten für Tabellen-Ansicht
     */
    public function getDetailedPaymentsData()
    {
        $intervals = $this->getActiveIntervals();
        $detailedData = [];

        foreach($intervals as $clearingtype => $interval){
            $date = Carbon::now()->subDays($interval);
            $payments = $this->getOpenPaymentsForClearingType($clearingtype, $interval);
            
            foreach($payments as $payment){
                $name = !isset($payment->shopping_order->shopping_user) ? 'Kein Name' : $payment->shopping_order->shopping_user->billing_firstname.' '.$payment->shopping_order->shopping_user->billing_lastname;
                $email = !isset($payment->shopping_order->shopping_user) ? 'Keine Email' : $payment->shopping_order->shopping_user->billing_email;
                $shipped = '<span class="badge badge-pill badge-'.$payment->shopping_order->getShippedColor().'">'.$payment->shopping_order->getShippedType().'</span>';
                
                // Countdown für nächste Erinnerung berechnen
                $countdown = $this->getNextReminderCountdown($payment);
                
                $detailedData[] = [
                    'clearingtype' => $clearingtype,
                    'clearingtype_name' => $this->getClearingtype($clearingtype),
                    'interval_days' => $interval,
                    'date_limit' => $date->format('d.m.Y H:i:s'),
                    'order_id' => $payment->shopping_order_id,
                    'payment_id' => $payment->id,
                    'amount' => $payment->amount,
                    'created_at' => $payment->created_at->format('d.m.Y H:i:s'),
                    'days_old' => $payment->created_at->diffInDays(now()),
                    'payment' => $payment, // Vollständiges Payment-Objekt für weitere Verarbeitung
                    'name' => $name,
                    'email' => $email,
                    'shipped' => $shipped,
                    'reminder' => $payment->reminder,
                    'reminder_date' => $payment->reminder_date ? $payment->reminder_date->format('d.m.Y H:i:s') : null,
                    'countdown' => $countdown,
                ];
            }
        }

        return $detailedData;
    }

    /**
     * Sende die nächste Zahlungserinnerung
     * noch kein reminder gesendet = 1. Zahlungserinnerung
     *  reminder > 0 die nächste zahlungserinnerung aus der liste holen
     */
    public function sendReminder($payment)
    {
      

        //holen der nächsten zahlungserinnerung
        $payment_reminder = $this->getReminder((int) $payment->reminder, $payment->clearingtype);
        if(!$payment_reminder){
            return false;
        }

        //zahlungserinnerung Platzhalter ersetzen.
        $payment_reminder = $this->replacePlaceholder($payment, $payment_reminder);

        //zahlungserinnerung senden
        $emailSent = $this->sendReminderEmail($payment, $payment_reminder);

        if ($emailSent) {
            $this->createLog(
                'email_sent',
                "Zahlungserinnerung E-Mail gesendet an: {$payment->shopping_order->shopping_user->billing_email}, Subject: {$payment_reminder->subject}",
               'ShoppingOrder',
                $payment->shopping_order_id,
                3
            );
        }

        //action ausführen
        if($payment_reminder->action === 'set_order_status_cancelled'){
            $this->setNoNPayment($payment);
            $payment->shopping_order->shipped = 10;
            $payment->shopping_order->save();
            $this->createLog(
                'action_completed',
                "Action abgeschlossen: Bestellung auf 'Storniert' gesetzt, Payment auf 'non' gesetzt",
                'ShoppingOrder',
                $payment->shopping_order_id,
                3
            );
        }
       
        //reminder setzen +1
        $payment->reminder = (int) $payment->reminder + 1;
        $payment->reminder_date = Carbon::now();
        $payment->save();

        $this->createLog(
            'reminder_completed',
            "Zahlungserinnerung für Payment ID: {$payment->id}, Order ID: {$payment->shopping_order_id}",
            'ShoppingOrder',
            $payment->shopping_order_id,
            4
        );

        return true;
    }

    public function setNoNPayment($payment)
    {
        $this->createLog(
            'set_non_payment',
            "Setze Payment ID: {$payment->id} auf 'non' Status",
            'ShoppingOrder',
            $payment->shopping_order_id,
            4
        );
        PaymentService::updateTransactionStatus($payment->shopping_order_id, 'non', $payment->id);
    }

    public function getClearingtype($clearingtype)
    {
       return isset($this->clearingtypes[$clearingtype]) ? $this->clearingtypes[$clearingtype] : $clearingtype;
    }

    public function getReminder($reminder, $clearingtype)
    {
        $payment_reminders = PaymentReminder::where('active', true)
            ->where('clearingtype', $clearingtype)
            ->orderBy('interval', 'asc')
            ->get();

        if($payment_reminders->isEmpty()) {
            return false;
        }
        // Wenn reminder größer ist als Anzahl der Erinnerungen
        if($reminder >= $payment_reminders->count()) {
            return false;
        }
        // Hole die Erinnerung an Position $reminder (0,1,2,3...)
        return $payment_reminders[$reminder];
    }

    public function replacePlaceholder($payment, $payment_reminder)
    {
        $shopping_order = $payment->shopping_order;
        $shopping_user = $shopping_order->shopping_user;

        $replacements = [
            '{billing_first_name}' => $shopping_user->billing_firstname,
            '{billing_last_name}' => $shopping_user->billing_lastname,
            '{order_number}' => '<b>'.$shopping_order->getLastShoppingPayment('reference').'</b>',
            '{order_date}' => '<b>'.$shopping_order->created_at->format('d.m.Y').'</b>',
            '{order_total}' => '<b>'.$shopping_order->getFormattedTotalShipping().'</b>'
        ];

        $payment_reminder->subject = str_replace(
            array_keys($replacements),
            array_values($replacements), 
            $payment_reminder->subject
        );

        $payment_reminder->message = str_replace(
            array_keys($replacements),
            array_values($replacements),
            $payment_reminder->message
        );

        return $payment_reminder;
    }

    public function sendReminderEmail($payment, $payment_reminder)
    {
        try {
            $email = $payment->shopping_order->shopping_user->billing_email;
            $subject = $payment_reminder->subject;
            $message = $payment_reminder->message;
            
            if(Util::isTestSystem()){
                $email = config('app.checkout_test_mail');
            }
            
            if($payment->shopping_order->mode === 'test' || Util::isTestSystem()){
                $bcc[] = config('app.checkout_test_mail');
            }else{
                $bcc[] = config('app.checkout_mail');
            }
            
            Mail::to($email)->bcc($bcc)->send(new PaymentReminderEmail($subject, $message, $payment->shopping_order));
            
            return true;
        } catch (\Exception $e) {
            \Log::error('Fehler beim E-Mail-Versand: ' . $e->getMessage());
            $this->createLog(
                'email_exception',
                "E-Mail Exception: " . $e->getMessage() . " für Payment ID: {$payment->id}",
                'ShoppingOrder',
                $payment->shopping_order_id,
                5
            );
            return false;
        }
    }

    /**
     * Berechnet den Countdown bis zur nächsten Zahlungserinnerung
     */
    public function getNextReminderCountdown($payment)
    {
        // Wenn noch keine Erinnerung gesendet wurde
        if ($payment->reminder == 0) {
            return null;
        }

        // Hole alle aktiven Erinnerungen für diesen Clearingtype
        $payment_reminders = PaymentReminder::where('active', true)
            ->where('clearingtype', $payment->clearingtype)
            ->orderBy('interval', 'asc')
            ->get();

        if ($payment_reminders->isEmpty()) {
            return null;
        }

        // Wenn alle Erinnerungen bereits gesendet wurden
        if ($payment->reminder >= $payment_reminders->count()) {
            return [
                'type' => 'completed',
                'message' => 'Alle Erinnerungen gesendet',
                'days_left' => 0
            ];
        }

        // Hole die nächste Erinnerung
        $next_reminder = $payment_reminders[$payment->reminder];
        
        // Berechne die Differenz zwischen aktuellem und nächstem Reminder
        $current_reminder = $payment_reminders[$payment->reminder - 1];
        $interval_difference = $next_reminder->interval - $current_reminder->interval;
        
        // Berechne das Datum der nächsten Erinnerung
        $next_reminder_date = Carbon::parse($payment->reminder_date)->addDays($interval_difference);
        
        // Berechne die verbleibenden Tage
        $days_left = Carbon::now()->diffInDays($next_reminder_date, false);
        
        // Wenn die nächste Erinnerung bereits fällig ist
        if ($days_left <= 0) {
            return [
                'type' => 'overdue',
                'message' => 'Nächste Erinnerung fällig',
                'days_left' => 0,
                'next_reminder_date' => $next_reminder_date
            ];
        }

        return [
            'type' => 'countdown',
            'message' => 'Nächste Erinnerung in ' . $days_left . ' Tagen',
            'days_left' => $days_left,
            'next_reminder_date' => $next_reminder_date,
            'next_reminder_interval' => $interval_difference
        ];
    }

    /**
     * Hole alle Logs für Payment Reminder
     */
    public function getPaymentReminderLogs($limit = 100, $paymentId = null, $action = null)
    {
        $query = Logger::where('channel', 'payment_reminder')
                      ->orderBy('created_at', 'desc');

        if ($paymentId) {
            $query->where('model_id', $paymentId);
        }

        if ($action) {
            $query->where('action', $action);
        }

        return $query->limit($limit)->get();
    }

    /**
     * Hole Logs für einen spezifischen Payment
     */
    public function getLogsForPayment($orderId)
    {
        return Logger::where('channel', 'payment_reminder')
                     ->where('model_id', $orderId)
                     ->orderBy('created_at', 'desc')
                     ->get();
    }

    /**
     * Hole Logs für einen spezifischen Zeitraum
     */
    public function getLogsForDateRange($startDate, $endDate)
    {
        return Logger::where('channel', 'payment_reminder')
                     ->whereBetween('created_at', [$startDate, $endDate])
                     ->orderBy('created_at', 'desc')
                     ->get();
    }

    /**
     * Hole Statistiken für Payment Reminder Logs
     */
    public function getLogStatistics($days = 30)
    {
        $startDate = Carbon::now()->subDays($days);
        
        $stats = Logger::where('channel', 'payment_reminder')
                      ->where('created_at', '>=', $startDate)
                      ->selectRaw('action, level, COUNT(*) as count')
                      ->groupBy('action', 'level')
                      ->get();

        $summary = [
            'total_logs' => Logger::where('channel', 'payment_reminder')
                                 ->where('created_at', '>=', $startDate)
                                 ->count(),
            'emails_sent' => Logger::where('channel', 'payment_reminder')
                                  ->where('action', 'email_sent')
                                  ->where('created_at', '>=', $startDate)
                                  ->count(),
            'emails_failed' => Logger::where('channel', 'payment_reminder')
                                    ->where('action', 'email_exception')
                                    ->where('created_at', '>=', $startDate)
                                    ->count(),
            'reminders_completed' => Logger::where('channel', 'payment_reminder')
                                          ->where('action', 'reminder_completed')
                                          ->where('created_at', '>=', $startDate)
                                          ->count(),
            'actions_executed' => Logger::where('channel', 'payment_reminder')
                                       ->where('action', 'action_completed')
                                       ->where('created_at', '>=', $startDate)
                                       ->count(),
        ];

        return [
            'summary' => $summary,
            'detailed_stats' => $stats
        ];
    }

}