// Configure Marked.js for Code Highlighting
marked.setOptions({
    highlight: function(code, lang) {
        const language = hljs.getLanguage(lang) ? lang : 'plaintext';
        return hljs.highlight(code, { language }).value;
    }
});

const chatBox = document.getElementById('chat-box');
const inputField = document.getElementById('user-input');
const sendBtn = document.getElementById('send-btn');
const themeToggle = document.getElementById('themeToggle');

// Theme Logic
themeToggle.addEventListener('click', () => {
    document.body.classList.toggle('dark-mode');
});

// Auto-resize Textarea up to a max height
inputField.addEventListener('input', function() {
    this.style.height = 'auto';
    this.style.height = Math.min(this.scrollHeight, 200) + 'px';
});

// Handle Enter (Send) vs Shift+Enter (New Line)
inputField.addEventListener('keydown', (e) => {
    if (e.key === 'Enter' && !e.shiftKey) {
        e.preventDefault();
        sendMessage();
    }
});

sendBtn.addEventListener('click', sendMessage);

async function sendMessage() {
    const text = inputField.value.trim();
    if (!text) return;

    // Reset UI
    inputField.value = '';
    inputField.style.height = 'auto';
    appendMessage('user', text);
    sendBtn.disabled = true;

    try {
        const response = await fetch('/api/chat', {
            method: 'POST',
            headers: { 'Content-Type': 'application/json' },
            body: JSON.stringify({ message: text })
        });
        
        const data = await response.json();
        
        if (response.ok) {
            appendMessage('ai', data.reply);
        } else {
            appendMessage('ai', `**Error:** ${data.detail}`);
        }
    } catch (error) {
        appendMessage('ai', `**Connection Error:** Please check your network.`);
    }

    sendBtn.disabled = false;
    inputField.focus();
}

function appendMessage(sender, text) {
    const msgDiv = document.createElement('div');
    msgDiv.classList.add('message');
    
    if (sender === 'ai') {
        msgDiv.classList.add('ai-msg');
        const htmlContent = marked.parse(text);
        msgDiv.innerHTML = `
            <div class="avatar">✦</div>
            <div class="content">${htmlContent}</div>
        `;
        
        // Add Copy Buttons to Code Blocks
        msgDiv.querySelectorAll('pre').forEach(pre => {
            const btn = document.createElement('button');
            btn.className = 'copy-btn';
            btn.innerText = 'Copy';
            btn.onclick = () => {
                const codeText = pre.querySelector('code').innerText;
                navigator.clipboard.writeText(codeText);
                btn.innerText = 'Copied!';
                setTimeout(() => btn.innerText = 'Copy', 2000);
            };
            pre.appendChild(btn);
        });
        
    } else {
        msgDiv.classList.add('user-msg');
        msgDiv.innerHTML = `<div class="content">${text}</div>`;
    }
    
    chatBox.appendChild(msgDiv);
    // Smooth scroll to bottom
    chatBox.scrollTo({ top: chatBox.scrollHeight, behavior: 'smooth' });
}