<?php

namespace App\Http\Controllers;

use Illuminate\Http\Request;
use App\Models\PhoneVerification;
use App\Models\Coupon;
use Illuminate\Support\Str;
use Illuminate\Support\Facades\Log;

class VerificationController extends Controller
{
    public function index()
    {
        return view('verification.index');
    }

    public function sendOtp(Request $request)
    {
        $request->validate([
            'phone' => ['required', 'regex:/^\+993 [67]\d \d{2} \d{2} \d{2}$/']
        ], [
            'phone.regex' => 'The phone number must be in the format: +993 KX XX XX XX (where K is 6 or 7).'
        ]);

        $phone = $request->phone;
        
        // Generate a 4-digit OTP
        $otp = (string) rand(1000, 9999);
        
        // Log it to simulate SMS
        Log::info("OTP for {$phone} is {$otp}");

        // Store in DB
        PhoneVerification::updateOrCreate(
            ['phone' => $phone],
            [
                'otp' => $otp,
                'expires_at' => now()->addMinutes(10),
                'verified' => false
            ]
        );

        // Store phone in session for the next step
        session()->put('verify_phone', $phone);

        return redirect()->route('verification.verify.form');
    }

    public function verifyForm()
    {
        if (!session()->has('verify_phone')) {
            return redirect()->route('verification.index');
        }

        return view('verification.verify', [
            'phone' => session()->get('verify_phone')
        ]);
    }

    public function verifyOtp(Request $request)
    {
        $request->validate([
            'phone' => 'required',
            'otp' => 'required|digits:4'
        ]);

        $verification = PhoneVerification::query()->where('phone', $request->phone)->first();

        if (!$verification || $verification->otp !== $request->otp) {
            return back()->withErrors(['otp' => 'Invalid OTP.']);
        }

        if ($verification->expires_at < now()) {
            return back()->withErrors(['otp' => 'OTP has expired.']);
        }

        // Mark as verified
        $verification->update(['verified' => true]);

        // Generate or get Coupon
        $coupon = Coupon::firstOrCreate(
            ['phone' => $request->phone],
            ['code' => $this->generateCouponCode()]
        );

        // Put coupon code in session for the congratulations page
        session()->put('coupon_code', $coupon->code);
        // Clear phone from session as verification is complete
        session()->forget('verify_phone');

        return redirect()->route('verification.congratulations');
    }

    public function congratulations()
    {
        if (!session()->has('coupon_code')) {
            return redirect()->route('verification.index');
        }

        return view('verification.congratulations', [
            'code' => session()->get('coupon_code')
        ]);
    }

    private function generateCouponCode()
    {
        // Format X_YYYY (X is integer, Y is capital char)
        $x = rand(1, 9);
        $yyyy = substr(str_shuffle("ABCDEFGHIJKLMNOPQRSTUVWXYZ"), 0, 4);

        return "{$x}_{$yyyy}";
    }
}