<?php

declare(strict_types=1);

require_once __DIR__ . '/../../vendor/autoload.php';

use App\Framework\QrCode\ErrorCorrection\ReedSolomonEncoder;

echo "=== Generator Polynomial Verification ===\n\n";

$rs = new ReedSolomonEncoder();
$reflection = new ReflectionClass($rs);

// Get generator polynomial for 10 EC codewords
$getGeneratorMethod = $reflection->getMethod('getGeneratorPolynomial');
$getGeneratorMethod->setAccessible(true);
$generator = $getGeneratorMethod->invoke($rs, 10);

echo "Current generator polynomial (10 EC codewords):\n";
echo "  [" . implode(', ', $generator) . "]\n\n";

// Expected from QR code specification
$expected = [0, 251, 67, 46, 61, 118, 70, 64, 94, 32, 45];

echo "Expected generator polynomial:\n";
echo "  [" . implode(', ', $expected) . "]\n\n";

if ($generator === $expected) {
    echo "✅ Generator polynomial matches!\n\n";
} else {
    echo "❌ Generator polynomial doesn't match!\n";
    echo "Differences:\n";
    for ($i = 0; $i < min(count($generator), count($expected)); $i++) {
        if ($generator[$i] !== $expected[$i]) {
            echo "  Coefficient {$i}: got {$generator[$i]}, expected {$expected[$i]}\n";
        }
    }
    echo "\n";
}

// Test: Generate polynomial dynamically
echo "=== Testing Dynamic Generation ===\n";
$generateMethod = $reflection->getMethod('generateGeneratorPolynomial');
$generateMethod->setAccessible(true);
$generated = $generateMethod->invoke($rs, 10);

echo "Dynamically generated:\n";
echo "  [" . implode(', ', $generated) . "]\n\n";

if ($generated === $expected) {
    echo "✅ Dynamic generation matches expected!\n";
} else {
    echo "❌ Dynamic generation doesn't match!\n";
    echo "This might be the problem - the generator polynomial is wrong.\n";
}

// Check if the issue is with the leading coefficient
// In QR codes, the generator polynomial should be monic (leading coefficient = 1)
// But our polynomials start with 0
echo "\n=== Generator Polynomial Format ===\n";
echo "Note: In our implementation, generator polynomials start with [0, ...]\n";
echo "This might be correct if we're using a different representation.\n";
echo "But let's check if the actual polynomial is correct.\n\n";

// The generator polynomial should be: g(x) = (x - α^0)(x - α^1)...(x - α^9)
// When expanded, this should give us the expected coefficients