document.addEventListener('DOMContentLoaded', function() {

    const textInput = document.getElementById('text');
    const clearTextBtn = document.getElementById('clear-text');
    const wifiSsidInput = document.getElementById('wifi-ssid');
    const wifiPasswordInput = document.getElementById('wifi-password');
    const sizeSelect = document.getElementById('size');
    const errorCorrectionSelect = document.getElementById('errorCorrection');
    const foregroundColor = document.getElementById('foreground');
    const backgroundColor = document.getElementById('background');
    const downloadBtn = document.getElementById('download');
    const qrcodeCanvas = document.getElementById('qrcode');
    const qrcodeImg = document.getElementById('qrcode-img');
    const errorMessage = document.getElementById('error-message');
    const infoButton = document.getElementById('info-button');
    const infoPanel = document.getElementById('info-panel');
    const infoClose = document.getElementById('info-close');
    const titleElement = document.getElementById('title');

    // Title Easter egg
    let titleClickCount = 0;
    let titleTimeoutId = null;

    titleElement.addEventListener('click', function() {
        titleClickCount++;
        clearTimeout(titleTimeoutId);

        if (titleClickCount === 1) {
            this.textContent = "Just a [bleep]ing QR Code";

            titleTimeoutId = setTimeout(() => {
                this.textContent = "Just a QR Code";
                titleClickCount = 0;
            }, 500);
        }
    });

    // Info panel toggle
    infoButton.addEventListener('click', function() {
        infoPanel.classList.add('open');
    });

    infoClose.addEventListener('click', function() {
        infoPanel.classList.remove('open');
    });

    // Close info panel when clicking outside
    document.addEventListener('click', function(event) {
        if (infoPanel.classList.contains('open') &&
            !infoPanel.contains(event.target) &&
            event.target !== infoButton) {
            infoPanel.classList.remove('open');
        }
    });

    // Close info panel with Escape key
    document.addEventListener('keydown', function(event) {
        if (event.key === 'Escape' && infoPanel.classList.contains('open')) {
            infoPanel.classList.remove('open');
        }
    });

    // Set random compliment as default text and select it
    textInput.value = 'https://medisoftware.de';
    textInput.select();

    // Show/hide clear button based on text input content
    function toggleClearButton() {
        if (textInput.value.length > 0) {
            clearTextBtn.style.display = 'block';
        } else {
            clearTextBtn.style.display = 'none';
        }
    }

    // Initialize clear button visibility
    toggleClearButton();

    // Clear text when clear button is clicked
    clearTextBtn.addEventListener('click', function() {
        textInput.value = '';
        wifiSsidInput.value = '';
        wifiPasswordInput.value = '';
        toggleClearButton();
        textInput.focus();
        generateQRCode();
    });

    // Update clear button visibility when text changes
    textInput.addEventListener('input', function() {
        toggleClearButton();
        // Only generate QR code if no wifi data is being entered
        const wifiSsid = wifiSsidInput.value.trim();
        const wifiPassword = wifiPasswordInput.value.trim();
        if (!wifiSsid && !wifiPassword) {
            generateQRCode();
        }
    });

    let qr = null;

    // Generate QR code when settings change
    sizeSelect.addEventListener('change', generateQRCode);
    errorCorrectionSelect.addEventListener('change', generateQRCode);
    foregroundColor.addEventListener('input', generateQRCode);
    backgroundColor.addEventListener('input', generateQRCode);

    // Generate QR code when wifi settings change
    wifiSsidInput.addEventListener('input', function() {
        updateTextDisplay();
        generateQRCode();
    });
    wifiPasswordInput.addEventListener('input', function() {
        updateTextDisplay();
        generateQRCode();
    });

    // Download QR code as image
    downloadBtn.addEventListener('click', downloadQRCode);

    // Or check for URL parameters if present
    const urlParams = new URLSearchParams(window.location.search);
    if (urlParams.has('text')) {
        const safeText = urlParams.get('text');
        // Nur erlaubte Zeichen (Buchstaben, Zahlen, gängige URL-Zeichen)
        if (/^[\w\-.:/?&=#%+@!;,]*$/i.test(safeText)) {
            textInput.value = safeText;
        }
    }
    if (urlParams.has('ssid')) {
        const safeSsid = urlParams.get('ssid');
        if (/^[^<>"'`\\]*$/.test(safeSsid)) {
            wifiSsidInput.value = safeSsid;
        }
    }
    if (urlParams.has('password')) {
        const safePassword = urlParams.get('password');
        if (/^[^<>"'`\\]*$/.test(safePassword)) {
            wifiPasswordInput.value = safePassword;
        }
    }
    if (urlParams.has('size')) {
        const sizeValue = urlParams.get('size');
        if (["128", "256", "512", "1024"].includes(sizeValue)) {
            sizeSelect.value = sizeValue;
        }
    }
    if (urlParams.has('errorCorrection')) {
        const ecValue = urlParams.get('errorCorrection').toUpperCase();
        if (["L", "M", "Q", "H"].includes(ecValue)) {
            errorCorrectionSelect.value = ecValue;
        }
    }
    if (urlParams.has('foreground')) {
        const fgValue = urlParams.get('foreground');
        if (/^#[0-9A-F]{6}$/i.test(fgValue)) {
            foregroundColor.value = fgValue;
        }
    }
    if (urlParams.has('background')) {
        const bgValue = urlParams.get('background');
        if (/^#[0-9A-F]{6}$/i.test(bgValue)) {
            backgroundColor.value = bgValue;
        }
    }
    generateQRCode();

    function generateQRCode() {
        const text = textInput.value.trim();
        const wifiSsid = wifiSsidInput.value.trim();
        const wifiPassword = wifiPasswordInput.value.trim();
        const size = parseInt(sizeSelect.value);
        const errorCorrection = errorCorrectionSelect.value.toLowerCase();
        const fgColor = foregroundColor.value;
        const bgColor = backgroundColor.value;

        // Update the gabe link color to match foreground color
        const gabeLink = document.querySelector('.credit a');
        if (gabeLink) {
            gabeLink.style.color = fgColor;
        }

        // Clear previous error
        errorMessage.textContent = '';
        downloadBtn.style.display = 'none';

        // Determine what to encode
        let qrText = text;
        
        // If wifi credentials are provided, generate wifi QR code
        if (wifiSsid && wifiPassword) {
            // Wifi QR code format: WIFI:S:<SSID>;T:WPA;P:<password>;;
            qrText = `WIFI:S:${escapeSpecialChars(wifiSsid)};T:WPA;P:${escapeSpecialChars(wifiPassword)};;`;
        } else if (wifiSsid && !wifiPassword) {
            // SSID only (open network)
            qrText = `WIFI:S:${escapeSpecialChars(wifiSsid)};T:nopass;;`;
        } else if (!wifiSsid && wifiPassword) {
            // Password without SSID is invalid
            errorMessage.textContent = 'Bitte geben Sie eine SSID ein, wenn Sie ein Passwort angeben';
            qrcodeCanvas.style.display = 'none';
            qrcodeImg.style.display = 'none';
            return;
        }

        // Validate input
        if (qrText === '') {
            errorMessage.textContent = 'Bitte geben Sie Text/URL oder Wifi-Daten ein';
            // Hide both canvas and image
            qrcodeCanvas.style.display = 'none';
            qrcodeImg.style.display = 'none';
            return;
        }

        // Create new QR code on canvas
        try {
            if (!qr) {
                qr = new QRious({
                    element: qrcodeCanvas,
                    size: size,
                    value: qrText,
                    foreground: fgColor,
                    background: bgColor,
                    level: errorCorrection
                });
            } else {
                qr.set({
                    size: size,
                    value: qrText,
                    foreground: fgColor,
                    background: bgColor,
                    level: errorCorrection
                });
            }

            // Convert canvas to image
            const dataURL = qrcodeCanvas.toDataURL('image/png');
            qrcodeImg.src = dataURL;

            // Show image (hide canvas) and download button
            qrcodeCanvas.style.display = 'none';
            qrcodeImg.style.display = 'block';
            downloadBtn.style.display = 'inline-block';
        } catch (err) {
            errorMessage.textContent = 'Error generating QR code: ' + err.message;
            qrcodeCanvas.style.display = 'none';
            qrcodeImg.style.display = 'none';
        }
    }

    // Helper function to escape special characters in wifi strings
    function escapeSpecialChars(str) {
        return str.replace(/[\\;:,]/g, '\\$&');
    }

    function downloadQRCode() {
        // Use the image source for download
        const link = document.createElement('a');
        link.download = 'qrcode.png';
        link.href = qrcodeImg.src;

        // Simulate click to trigger download
        document.body.appendChild(link);
        link.click();
        document.body.removeChild(link);

        // Show success feedback
        const originalText = downloadBtn.textContent;
        downloadBtn.textContent = 'Downloaded!';

        // Reset button after a short delay
        setTimeout(() => {
            downloadBtn.textContent = originalText;
        }, 2000);
    }

    // Function to update the text display with current QR code content
    function updateTextDisplay() {
        const wifiSsid = wifiSsidInput.value.trim();
        const wifiPassword = wifiPasswordInput.value.trim();
        
        if (wifiSsid && wifiPassword) {
            // Show wifi QR code format
            textInput.value = `WIFI:S:${escapeSpecialChars(wifiSsid)};T:WPA;P:${escapeSpecialChars(wifiPassword)};;`;
        } else if (wifiSsid && !wifiPassword) {
            // Show open network format
            textInput.value = `WIFI:S:${escapeSpecialChars(wifiSsid)};T:nopass;;`;
        } else {
            // If no wifi data, keep original text input value
            // Don't change it here to avoid overwriting user input
        }
        
        // Update clear button visibility
        toggleClearButton();
    }
});