function sendMessage() {
    const inputField = document.getElementById('userInput');
    const message = inputField.value.trim();
    const imageUpload = document.getElementById('imageUpload').files[0];
    const complexity = document.getElementById('complexity').value;
    const model = document.getElementById('model').value; // Get the selected model
    const chatbox = document.getElementById('chatbox');

    if (message === "" && !imageUpload) return;

    // Append user message
    const userMessageDiv = document.createElement('div');
    userMessageDiv.classList.add('user-message');
    const userText = document.createElement('span');
    userText.textContent = message;
    userMessageDiv.appendChild(userText);

    if (imageUpload) {
        const imagePreview = document.createElement('img');
        imagePreview.src = URL.createObjectURL(imageUpload);
        imagePreview.style.maxWidth = '100px';
        imagePreview.style.maxHeight = '100px';
        imagePreview.style.marginTop = '10px';
        userMessageDiv.appendChild(imagePreview);
    }

    chatbox.appendChild(userMessageDiv);

    // Clear input field
    inputField.value = '';
    document.getElementById('imageUpload').value = '';

    // Scroll chatbox to the bottom
    chatbox.scrollTop = chatbox.scrollHeight;

    // Send request to Flask backend
    const formData = new FormData();
    formData.append('image', imageUpload);
    formData.append('question', message);
    formData.append('complexity', complexity);
    formData.append('model', model);  // Append selected model

    fetch('/ask', {
        method: 'POST',
        body: formData
    })
    .then(response => response.json())
    .then(data => {
        const botMessageDiv = document.createElement('div');
        botMessageDiv.classList.add('bot-message');
        const botText = document.createElement('span');
        botText.textContent = data.answer;
        botMessageDiv.appendChild(botText);
        chatbox.appendChild(botMessageDiv);

        // Scroll chatbox to the bottom
        chatbox.scrollTop = chatbox.scrollHeight;
    })
    .catch(error => {
        console.error('Error:', error);
    });
}