<?php

declare(strict_types=1);

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

use App\Framework\QrCode\QrCodeGenerator;
use App\Framework\QrCode\Structure\FormatInformation;
use App\Framework\QrCode\ValueObjects\ErrorCorrectionLevel;
use App\Framework\QrCode\ValueObjects\QrCodeConfig;
use App\Framework\QrCode\ValueObjects\QrCodeVersion;
use App\Framework\QrCode\ValueObjects\EncodingMode;

echo "=== Format Information Debug ===\n\n";

$testData = 'HELLO WORLD';
$config = new QrCodeConfig(
    version: QrCodeVersion::fromNumber(1),
    errorCorrectionLevel: ErrorCorrectionLevel::M,
    encodingMode: EncodingMode::BYTE
);

$matrix = QrCodeGenerator::generate($testData, $config);

// Read format information from matrix
$formatCols = [0, 1, 2, 3, 4, 5, 7, 8, 20, 19, 18, 17, 16, 15, 14];
$formatH = '';
foreach ($formatCols as $col) {
    $formatH .= $matrix->getModuleAt(8, $col)->isDark() ? '1' : '0';
}

echo "Format Information (Horizontal): {$formatH}\n";
echo "Binary: " . str_pad(decbin(bindec($formatH)), 15, '0', STR_PAD_LEFT) . "\n";
echo "Decimal: " . bindec($formatH) . "\n\n";

// Unmask with XOR mask
$xorMask = "101010000010010";
$unmasked = '';
for ($i = 0; $i < 15; $i++) {
    $unmasked .= (int)$formatH[$i] ^ (int)$xorMask[$i];
}

echo "Unmasked (XOR with mask): {$unmasked}\n";
echo "Binary: " . str_pad(decbin(bindec($unmasked)), 15, '0', STR_PAD_LEFT) . "\n";
echo "Decimal: " . bindec($unmasked) . "\n\n";

// Decode
$ecBits = substr($unmasked, 0, 2);
$maskBits = substr($unmasked, 2, 5);
$bchBits = substr($unmasked, 5); // BCH error correction bits

echo "EC Level bits: {$ecBits}\n";
echo "Mask Pattern bits: {$maskBits}\n";
echo "BCH bits: {$bchBits}\n\n";

$ecLevel = match($ecBits) {
    '01' => 'L',
    '00' => 'M',
    '11' => 'Q',
    '10' => 'H',
    default => 'UNKNOWN'
};

$maskPattern = bindec($maskBits);

echo "Decoded:\n";
echo "  EC Level: {$ecLevel}\n";
echo "  Mask Pattern: {$maskPattern} (binary: {$maskBits})\n\n";

if ($maskPattern > 7) {
    echo "❌ PROBLEM: Mask Pattern {$maskPattern} is invalid (should be 0-7)!\n\n";
    
    // Check what the mask bits should be
    echo "Expected mask bits for Level M:\n";
    $expectedMasks = [
        0 => "000",
        1 => "001",
        2 => "010",
        3 => "011",
        4 => "100",
        5 => "101",
        6 => "110",
        7 => "111",
    ];
    
    foreach ($expectedMasks as $pattern => $bits) {
        echo "  Pattern {$pattern}: {$bits}\n";
    }
    
    echo "\nActual mask bits: {$maskBits} (5 bits, but should be 3 bits)\n";
    echo "The problem is that we're reading 5 bits instead of 3!\n\n";
    
    // Check what the correct format should be
    // Format: [EC(2 bits)][Mask(3 bits)][BCH(10 bits)]
    echo "Correct format structure:\n";
    echo "  Bits 0-1: EC Level (2 bits)\n";
    echo "  Bits 2-4: Mask Pattern (3 bits)\n";
    echo "  Bits 5-14: BCH error correction (10 bits)\n\n";
    
    // Try reading only 3 bits for mask
    $maskBits3 = substr($unmasked, 2, 3);
    $maskPattern3 = bindec($maskBits3);
    echo "Mask Pattern (3 bits): {$maskBits3} = {$maskPattern3}\n";
    
    if ($maskPattern3 <= 7) {
        echo "✅ This is correct! The mask pattern should be read as 3 bits, not 5!\n";
    }
} else {
    echo "✅ Mask Pattern is valid\n";
}

// Check what mask pattern was actually used
echo "\n=== Checking Actual Mask Pattern Used ===\n";
// We need to check which mask pattern was selected by the evaluator
// But we can't easily access that from the generated matrix
// Instead, let's check the format information table

$reflection = new \ReflectionClass(FormatInformation::class);
$formatTable = $reflection->getConstant('FORMAT_INFO_TABLE');

echo "Format Information Table for Level M:\n";
foreach ($formatTable['M'] as $pattern => $bits) {
    $bitsStr = str_pad(decbin($bits), 15, '0', STR_PAD_LEFT);
    echo "  Pattern {$pattern}: {$bitsStr} (decimal: {$bits})\n";
    
    // Check if this matches our format
    if ($bitsStr === $formatH) {
        echo "    ✅ MATCHES!\n";
    }
}