const launcher = document.getElementById('askross-launcher');
const openChat = document.getElementById('open-chat');
const closeChat = document.getElementById('close-chat');
const chatbotContainer = document.getElementById('chatbot-container');
const chatForm = document.getElementById('chat-form');
const userInput = document.getElementById('user-input');
const chatMessages = document.getElementById('chat-messages');
const typingIndicator = document.getElementById('typing-indicator');
const scrollBottom = document.getElementById('scroll-bottom');

let thread_id = localStorage.getItem('askross_thread_id');
if (!thread_id) {
    thread_id = crypto.randomUUID();
    localStorage.setItem('askross_thread_id', thread_id);
}

const pageContext = {
    page_id: window.location.pathname === '/' ? 'home' : 'page',
    page_title: document.title || 'AskRoss',
};

let isFirstMessage = true;

const homepageQuestions = [
    "How can I get a mortgage if the bank said no?",
    "What mortgage services do you offer?",
    "Can I refinance my home?",
    "How do I improve my credit score?"
];

// ✅ Welcome + Suggestions (clean spacing)
function showSuggestions() {
    const wrapper = document.createElement('div');
    wrapper.className = 'suggestions-wrapper';

    const welcome = document.createElement('div');
    welcome.className = 'welcome-message';
    welcome.innerHTML = `<div class="bubble"><strong>Hi, I’m AskRoss 👋</strong><br>Simple mortgage advice — even if the bank said no.</div>`;

    const divider = document.createElement('div');
    divider.className = 'suggestion-divider';
    divider.textContent = 'Popular questions';

    wrapper.appendChild(welcome);
    wrapper.appendChild(divider);

    homepageQuestions.forEach(q => {
        const btn = document.createElement('button');
        btn.className = 'suggestion-btn';
        btn.textContent = q;
        btn.onclick = () => sendMessage(q);
        wrapper.appendChild(btn);
    });

    chatMessages.appendChild(wrapper);
}

// OPEN
openChat.addEventListener('click', () => {
    chatbotContainer.classList.add('open');
    launcher.style.display = 'none';

    if (chatMessages.children.length === 0) {
        showSuggestions();
    }
});

// CLOSE
closeChat.addEventListener('click', () => {
    chatbotContainer.classList.remove('open');
    launcher.style.display = 'flex';
});

// Initialize closed by default
chatbotContainer.classList.remove('open');
launcher.style.display = 'flex';

// SEND
async function sendMessage(message) {
    if (!message) return;

    if (isFirstMessage) {
        chatMessages.innerHTML = '';
        isFirstMessage = false;
    }

    appendMessage('user', message);
    typingIndicator.classList.remove('hidden');
    scrollToBottom();

    try {
        const response = await fetch('/chat', {
            method: 'POST',
            headers: {'Content-Type': 'application/json'},
            body: JSON.stringify({
                message,
                thread_id,
                page_id: pageContext.page_id,
                page_title: pageContext.page_title
            })
        });

        const data = await response.json();
        typingIndicator.classList.add('hidden');

        if (data.message) {
            appendMessage('bot', data.message);
        } else {
            appendMessage('bot', "Sorry, something went wrong");
        }
        updateScrollButton();
        scrollToBotMessage();

    } catch {
        typingIndicator.classList.add('hidden');
        appendMessage('bot', "Network error. Please try again.");
        updateScrollButton();
        scrollToBottom();
    }

    updateScrollButton();
}

function updateScrollButton() {
    const nearBottom = chatMessages.scrollHeight - chatMessages.scrollTop - chatMessages.clientHeight < 80;
    scrollBottom.classList.toggle('hidden', nearBottom);
}

chatMessages.addEventListener('scroll', updateScrollButton);
scrollBottom.addEventListener('click', () => {
    scrollToBottom();
    updateScrollButton();
});

chatForm.addEventListener('submit', (e) => {
    e.preventDefault();
    const message = userInput.value.trim();
    if (!message) return;

    userInput.value = '';
    sendMessage(message);
});

// Markdown
function escapeHtml(text) {
    return text
        .replace(/&/g,'&amp;')
        .replace(/</g,'&lt;')
        .replace(/>/g,'&gt;');
}

function normalizeMarkdownLinks(md) {
    let normalized = md;
    normalized = normalized.replace(/<a\s+href="(https?:\/\/[^\s"<>]+)"[^>]*>([^<]+)<\/a>/gi, '[$2]($1)');
    normalized = normalized.replace(/(https?:\/\/[^\s"<>]+)(?:"\s*target="[^"]*"\s*rel="[^"]*"\s*>|\s*target="[^"]*"\s*rel="[^"]*"\s*>|>)([^\n<>]+)/gi, '[$2]($1)');
    return normalized;
}

function markdownToHtml(md) {
    const normalized = normalizeMarkdownLinks(md);
    const html = marked.parse(normalized);
    return DOMPurify.sanitize(html, {ADD_ATTR: ['target', 'rel']});
}

// ✅ Messages (NO avatars)
function appendMessage(sender, text) {
    const wrapper = document.createElement('div');
    wrapper.className = `message ${sender}`;

    const bubble = document.createElement('div');
    bubble.className = 'bubble';

    if (sender === 'bot') {
        bubble.innerHTML = markdownToHtml(text);
    } else {
        bubble.textContent = text;
    }

    wrapper.appendChild(bubble);
    chatMessages.appendChild(wrapper);
}

function scrollToBottom() {
    chatMessages.scrollTo({
        top: chatMessages.scrollHeight,
        behavior: 'smooth'
    });
}

function scrollToBotMessage() {
    const lastBot = chatMessages.querySelector('.message.bot:last-child');
    if (lastBot) {
        lastBot.scrollIntoView({ behavior: 'smooth', block: 'start' });
    } else {
        scrollToBottom();
    }
}