/* CheddahBot Frontend JS */

// ── Session Management ──
const SESSION_KEY = 'cheddahbot_session';

function getSession() {
    try { return JSON.parse(localStorage.getItem(SESSION_KEY) || '{}'); }
    catch { return {}; }
}

function saveSession(data) {
    const s = getSession();
    Object.assign(s, data);
    localStorage.setItem(SESSION_KEY, JSON.stringify(s));
}

function getActiveAgent() {
    return getSession().agent_name || document.getElementById('input-agent-name')?.value || 'default';
}

// ── Agent Switching ──
function switchAgent(name) {
    // Update UI
    document.querySelectorAll('.agent-btn').forEach(b => {
        b.classList.toggle('active', b.dataset.agent === name);
    });
    document.getElementById('input-agent-name').value = name;
    document.getElementById('input-conv-id').value = '';
    saveSession({ agent_name: name, conv_id: null });

    // Clear chat and load new sidebar
    document.getElementById('chat-messages').innerHTML = '';
    refreshSidebar();
}

function setActiveAgent(name) {
    document.querySelectorAll('.agent-btn').forEach(b => {
        b.classList.toggle('active', b.dataset.agent === name);
    });
    const agentInput = document.getElementById('input-agent-name');
    if (agentInput) agentInput.value = name;
}

// ── Sidebar ──
function refreshSidebar() {
    const agent = getActiveAgent();
    htmx.ajax('GET', '/chat/conversations?agent_name=' + agent, {
        target: '#sidebar-conversations',
        swap: 'innerHTML'
    });
}

// ── Conversation Loading ──
function loadConversation(convId) {
    const agent = getActiveAgent();
    document.getElementById('input-conv-id').value = convId;
    saveSession({ conv_id: convId });

    htmx.ajax('GET', '/chat/load/' + convId + '?agent_name=' + agent, {
        target: '#chat-messages',
        swap: 'innerHTML'
    }).then(() => {
        scrollChat();
        renderAllMarkdown();
    });
}

// ── Chat Input ──
function handleKeydown(e) {
    if (e.key === 'Enter' && !e.shiftKey) {
        e.preventDefault();
        document.getElementById('chat-form').requestSubmit();
    }
}

function autoResize(el) {
    el.style.height = 'auto';
    el.style.height = Math.min(el.scrollHeight, 200) + 'px';
}

function afterSend(event) {
    const input = document.getElementById('chat-input');
    input.value = '';
    input.style.height = 'auto';

    // Clear file input and preview
    const fileInput = document.querySelector('input[type="file"]');
    if (fileInput) fileInput.value = '';
    const preview = document.getElementById('file-preview');
    if (preview) { preview.style.display = 'none'; preview.innerHTML = ''; }

    scrollChat();
}

function scrollChat() {
    const el = document.getElementById('chat-messages');
    if (el) {
        requestAnimationFrame(() => {
            el.scrollTop = el.scrollHeight;
        });
    }
}

// ── File Upload Preview ──
function showFileNames(input) {
    const preview = document.getElementById('file-preview');
    if (!input.files.length) {
        preview.style.display = 'none';
        return;
    }
    let html = '';
    for (const f of input.files) {
        html += '<span class="file-tag">' + f.name + '</span>';
    }
    preview.innerHTML = html;
    preview.style.display = 'block';
}

// Drag and drop
document.addEventListener('DOMContentLoaded', () => {
    const chatMain = document.querySelector('.chat-main');
    if (!chatMain) return;

    chatMain.addEventListener('dragover', e => {
        e.preventDefault();
        chatMain.style.outline = '2px dashed var(--accent)';
    });
    chatMain.addEventListener('dragleave', () => {
        chatMain.style.outline = '';
    });
    chatMain.addEventListener('drop', e => {
        e.preventDefault();
        chatMain.style.outline = '';
        const fileInput = document.querySelector('input[type="file"]');
        if (fileInput && e.dataTransfer.files.length) {
            fileInput.files = e.dataTransfer.files;
            showFileNames(fileInput);
        }
    });
});

// ── SSE Streaming ──
// Handle SSE chunks for chat streaming
let streamBuffer = '';
let activeSSE = null;

document.addEventListener('htmx:sseBeforeMessage', function(e) {
    // This fires for each SSE event received by htmx
});

// Watch for SSE trigger divs being added to the DOM
const observer = new MutationObserver(mutations => {
    for (const m of mutations) {
        for (const node of m.addedNodes) {
            if (node.id === 'sse-trigger') {
                setupStream(node);
            }
        }
    }
});

document.addEventListener('DOMContentLoaded', () => {
    const chatMessages = document.getElementById('chat-messages');
    if (chatMessages) {
        observer.observe(chatMessages, { childList: true, subtree: true });
    }
});

function setupStream(triggerDiv) {
    const sseUrl = triggerDiv.getAttribute('sse-connect');
    if (!sseUrl) return;

    // Remove the htmx SSE to manage manually
    triggerDiv.remove();

    const responseDiv = document.getElementById('assistant-response');
    if (!responseDiv) return;

    streamBuffer = '';

    // Show typing indicator
    responseDiv.innerHTML = '<div class="typing-indicator"><span></span><span></span><span></span></div>';

    const source = new EventSource(sseUrl);
    activeSSE = source;

    source.addEventListener('chunk', function(e) {
        if (streamBuffer === '') {
            // Remove typing indicator on first chunk
            responseDiv.innerHTML = '';
        }
        streamBuffer += e.data;
        // Render markdown
        try {
            responseDiv.innerHTML = marked.parse(streamBuffer);
        } catch {
            responseDiv.textContent = streamBuffer;
        }
        scrollChat();
    });

    source.addEventListener('done', function(e) {
        source.close();
        activeSSE = null;
        // Final markdown render
        if (streamBuffer) {
            try {
                responseDiv.innerHTML = marked.parse(streamBuffer);
            } catch {
                responseDiv.textContent = streamBuffer;
            }
        }
        streamBuffer = '';

        // Update conv_id from done event data
        const convId = e.data;
        if (convId) {
            document.getElementById('input-conv-id').value = convId;
            saveSession({ conv_id: convId });
        }

        // Refresh sidebar
        refreshSidebar();
        scrollChat();
    });

    source.onerror = function() {
        source.close();
        activeSSE = null;
        if (!streamBuffer) {
            responseDiv.innerHTML = '<span class="text-err">Connection lost</span>';
        }
    };
}

// ── Markdown Rendering ──
function renderAllMarkdown() {
    document.querySelectorAll('.message-content').forEach(el => {
        const raw = el.textContent;
        if (raw && typeof marked !== 'undefined') {
            try {
                el.innerHTML = marked.parse(raw);
            } catch { /* keep raw text */ }
        }
    });
}

// ── Mobile Sidebar ──
function toggleSidebar() {
    const sidebar = document.getElementById('chat-sidebar');
    const overlay = document.getElementById('sidebar-overlay');
    if (sidebar) {
        sidebar.classList.toggle('open');
    }
    if (overlay) {
        overlay.classList.toggle('visible');
    }
}

// ── Notification Banner (chat page) ──
function setupChatNotifications() {
    const banner = document.getElementById('notification-banner');
    if (!banner) return;

    const source = new EventSource('/sse/notifications');
    source.addEventListener('notification', function(e) {
        const notif = JSON.parse(e.data);
        banner.textContent = notif.message;
        banner.style.display = 'block';
        // Auto-hide after 15s
        setTimeout(() => { banner.style.display = 'none'; }, 15000);
    });
}

document.addEventListener('DOMContentLoaded', setupChatNotifications);

// ── HTMX Events ──
document.addEventListener('scrollChat', scrollChat);
document.addEventListener('htmx:afterSwap', function(e) {
    if (e.target.id === 'chat-messages') {
        renderAllMarkdown();
        scrollChat();
    }
});