// DNS Things - Punycode Module

// Real Punycode conversion functions using punycode.js library
function toPunycode(domain) {
    try {
        // Check if punycode library is available
        if (typeof punycode === 'undefined') {
            throw new Error('Punycode library not loaded');
        }
        
        // Split domain into parts and convert each part
        const parts = domain.split('.');
        const convertedParts = parts.map(part => {
            // Check if part contains non-ASCII characters
            if (/[^\x00-\x7F]/.test(part)) {
                return punycode.toASCII(part);
            }
            return part;
        });
        
        return convertedParts.join('.');
    } catch (error) {
        // Fallback to URL API if punycode library fails
        try {
            const url = new URL(`http://${domain}`);
            return url.hostname;
        } catch {
            throw new Error('Invalid domain format');
        }
    }
}

function fromPunycode(domain) {
    try {
        // Check if domain contains punycode
        if (!domain.includes('xn--')) {
            return domain; // No punycode to convert
        }
        
        // Check if punycode library is available
        if (typeof punycode === 'undefined') {
            throw new Error('Punycode library not loaded');
        }
        
        // Split domain into parts and convert each part
        const parts = domain.split('.');
        const convertedParts = parts.map(part => {
            if (part.startsWith('xn--')) {
                try {
                    return punycode.toUnicode(part);
                } catch {
                    return part; // Return original if conversion fails
                }
            }
            return part;
        });
        
        return convertedParts.join('.');
    } catch (error) {
        throw new Error('Invalid punycode format');
    }
}

// Initialize IDN Punycode Converter
function initPunycodeConverter() {
    const unicodeInput = document.getElementById('unicode-input');
    const punycodeInput = document.getElementById('punycode-input');
    const unicodeToPunycodeBtn = document.getElementById('unicode-to-punycode-btn');
    const punycodeToUnicodeBtn = document.getElementById('punycode-to-unicode-btn');
    const punycodeResult = document.getElementById('punycode-result');
    const unicodeResult = document.getElementById('unicode-result');

    if (!unicodeInput || !punycodeInput) return;

    // Unicode to Punycode conversion
    const convertUnicodeToPunycode = () => {
        const input = unicodeInput.value.trim();
        if (!input) {
            punycodeResult.innerHTML = '';
            return;
        }

        try {
            const converted = toPunycode(input);
            const isConverted = converted !== input;
            
            punycodeResult.innerHTML = `
                <div class="p-4 bg-green-50 dark:bg-green-900/30 rounded-lg">
                    <div class="flex justify-between items-start">
                        <div class="flex-1">
                            <h5 class="font-medium text-green-800 dark:text-green-200 mb-2">Punycode Result:</h5>
                            <div class="font-mono text-sm break-all p-2 bg-white dark:bg-gray-800 rounded border">${converted}</div>
                            ${isConverted ? '<p class="text-xs text-green-600 dark:text-green-400 mt-2">✅ Conversion applied</p>' : '<p class="text-xs text-gray-500 dark:text-gray-400 mt-2">ℹ️ No conversion needed (ASCII only)</p>'}
                        </div>
                        <button onclick="copyToClipboard('${converted}', this)" class="ml-2 p-2 text-green-600 dark:text-green-400 hover:bg-green-100 dark:hover:bg-green-800 rounded" title="Copy to clipboard">
                            <svg class="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                                <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M8 16H6a2 2 0 01-2-2V6a2 2 0 012-2h8a2 2 0 012 2v2m-6 12h8a2 2 0 002-2v-8a2 2 0 00-2-2h-8a2 2 0 00-2 2v8a2 2 0 002 2z"></path>
                            </svg>
                        </button>
                    </div>
                </div>
            `;
        } catch (error) {
            punycodeResult.innerHTML = `
                <div class="p-4 bg-red-50 dark:bg-red-900/30 text-red-700 dark:text-red-300 rounded-lg">
                    <h5 class="font-medium mb-1">Error:</h5>
                    <p class="text-sm">${error.message}</p>
                </div>
            `;
        }
    };

    // Punycode to Unicode conversion
    const convertPunycodeToUnicode = () => {
        const input = punycodeInput.value.trim();
        if (!input) {
            unicodeResult.innerHTML = '';
            return;
        }

        try {
            const converted = fromPunycode(input);
            const isConverted = converted !== input;
            
            unicodeResult.innerHTML = `
                <div class="p-4 bg-green-50 dark:bg-green-900/30 rounded-lg">
                    <div class="flex justify-between items-start">
                        <div class="flex-1">
                            <h5 class="font-medium text-green-800 dark:text-green-200 mb-2">Unicode Result:</h5>
                            <div class="font-mono text-sm break-all p-2 bg-white dark:bg-gray-800 rounded border">${converted}</div>
                            ${isConverted ? '<p class="text-xs text-green-600 dark:text-green-400 mt-2">✅ Conversion applied</p>' : '<p class="text-xs text-gray-500 dark:text-gray-400 mt-2">ℹ️ No conversion needed (no punycode found)</p>'}
                        </div>
                        <button onclick="copyToClipboard('${converted}', this)" class="ml-2 p-2 text-green-600 dark:text-green-400 hover:bg-green-100 dark:hover:bg-green-800 rounded" title="Copy to clipboard">
                            <svg class="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                                <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M8 16H6a2 2 0 01-2-2V6a2 2 0 012-2h8a2 2 0 012 2v2m-6 12h8a2 2 0 002-2v-8a2 2 0 00-2 2v8a2 2 0 002 2z"></path>
                            </svg>
                        </button>
                    </div>
                </div>
            `;
        } catch (error) {
            unicodeResult.innerHTML = `
                <div class="p-4 bg-red-50 dark:bg-red-900/30 text-red-700 dark:text-red-300 rounded-lg">
                    <h5 class="font-medium mb-1">Error:</h5>
                    <p class="text-sm">${error.message}</p>
                </div>
            `;
        }
    };

    // Event listeners
    unicodeToPunycodeBtn.addEventListener('click', convertUnicodeToPunycode);
    punycodeToUnicodeBtn.addEventListener('click', convertPunycodeToUnicode);

    // Auto-convert on input (with debounce)
    let unicodeTimeout, punycodeTimeout;
    
    unicodeInput.addEventListener('input', () => {
        clearTimeout(unicodeTimeout);
        unicodeTimeout = setTimeout(convertUnicodeToPunycode, 500);
    });
    
    punycodeInput.addEventListener('input', () => {
        clearTimeout(punycodeTimeout);
        punycodeTimeout = setTimeout(convertPunycodeToUnicode, 500);
    });

    // Paste support
    unicodeInput.addEventListener('paste', () => {
        setTimeout(convertUnicodeToPunycode, 100);
    });
    
    punycodeInput.addEventListener('paste', () => {
        setTimeout(convertPunycodeToUnicode, 100);
    });
}