// Configuration
let config = {
  apiBaseUrl: '/biz.payfrit.com/api',
  businessId: null,
  servicePointId: null,
  refreshInterval: 5000, // 5 seconds
};

// State
let orders = [];
let refreshTimer = null;

// Status ID mapping
const STATUS = {
  NEW: 1,
  PREPARING: 2,
  READY: 3,
  COMPLETED: 4
};

const STATUS_NAMES = {
  1: 'New',
  2: 'Preparing',
  3: 'Ready',
  4: 'Completed'
};

// Initialize
document.addEventListener('DOMContentLoaded', () => {
  loadConfig();
  startAutoRefresh();
});

// Load config from localStorage
function loadConfig() {
  const saved = localStorage.getItem('kds_config');
  if (saved) {
    try {
      const parsed = JSON.parse(saved);
      config.businessId = parsed.businessId || null;
      config.servicePointId = parsed.servicePointId || null;
      config.refreshInterval = (parsed.refreshInterval || 5) * 1000;

      document.getElementById('businessIdInput').value = config.businessId || '';
      document.getElementById('servicePointIdInput').value = config.servicePointId || '';
      document.getElementById('refreshIntervalInput').value = config.refreshInterval / 1000;
    } catch (e) {
      console.error('Failed to load config:', e);
    }
  }

  // If no business ID, show config panel
  if (!config.businessId) {
    toggleConfig();
  }
}

// Save config to localStorage
function saveConfig() {
  const businessId = parseInt(document.getElementById('businessIdInput').value) || null;
  const servicePointId = parseInt(document.getElementById('servicePointIdInput').value) || null;
  const refreshInterval = parseInt(document.getElementById('refreshIntervalInput').value) || 5;

  if (!businessId) {
    alert('Business ID is required');
    return;
  }

  config.businessId = businessId;
  config.servicePointId = servicePointId;
  config.refreshInterval = refreshInterval * 1000;

  localStorage.setItem('kds_config', JSON.stringify({
    businessId: config.businessId,
    servicePointId: config.servicePointId,
    refreshInterval: refreshInterval
  }));

  toggleConfig();
  location.reload();
}

// Toggle config panel
function toggleConfig() {
  const panel = document.getElementById('configPanel');
  panel.classList.toggle('show');
}

// Start auto-refresh
function startAutoRefresh() {
  if (!config.businessId) return;

  loadOrders();

  if (refreshTimer) clearInterval(refreshTimer);
  refreshTimer = setInterval(loadOrders, config.refreshInterval);
}

// Load orders from API
async function loadOrders() {
  if (!config.businessId) return;

  console.log('[loadOrders] Fetching with BusinessID:', config.businessId, 'ServicePointID:', config.servicePointId);

  try {
    const url = `${config.apiBaseUrl}/orders/listForKDS.cfm`;
    console.log('[loadOrders] URL:', url);

    const response = await fetch(url, {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
      },
      body: JSON.stringify({
        BusinessID: config.businessId,
        ServicePointID: config.servicePointId || 0
      })
    });

    console.log('[loadOrders] Response status:', response.status);
    const data = await response.json();
    console.log('[loadOrders] Response data:', data);

    if (data.OK) {
      orders = data.ORDERS || [];
      console.log('[loadOrders] Orders received:', orders.length);
      if (orders.length > 0) {
        console.log('[loadOrders] First order LineItems:', orders[0].LineItems);
      }
      renderOrders();
      updateStatus(true, `${orders.length} active orders`);
    } else {
      console.error('[loadOrders] API returned OK=false:', data);
      updateStatus(false, `Error: ${data.MESSAGE || data.ERROR}`);
    }
  } catch (error) {
    console.error('Failed to load orders:', error);
    updateStatus(false, 'Connection error');
  }
}

// Update status indicator
function updateStatus(isConnected, message) {
  const dot = document.getElementById('statusDot');
  const text = document.getElementById('statusText');

  if (isConnected) {
    dot.classList.remove('error');
    text.textContent = message || 'Connected';
  } else {
    dot.classList.add('error');
    text.textContent = message || 'Disconnected';
  }
}

// Render orders to DOM
function renderOrders() {
  const grid = document.getElementById('ordersGrid');

  if (orders.length === 0) {
    grid.innerHTML = `
      <div class="empty-state">
        <svg xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke="currentColor">
          <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M9 5H7a2 2 0 00-2 2v12a2 2 0 002 2h10a2 2 0 002-2V7a2 2 0 00-2-2h-2M9 5a2 2 0 002 2h2a2 2 0 002-2M9 5a2 2 0 012-2h2a2 2 0 012 2" />
        </svg>
        <h2>No Active Orders</h2>
        <p>New orders will appear here automatically</p>
      </div>
    `;
    return;
  }

  grid.innerHTML = orders.map(order => renderOrder(order)).join('');
}

// Render single order card
function renderOrder(order) {
  const statusClass = getStatusClass(order.OrderStatusID);
  const elapsedTime = getElapsedTime(order.OrderSubmittedOn);
  const timeClass = getTimeClass(elapsedTime);

  // Group line items by root items and their modifiers
  const rootItems = order.LineItems.filter(item => item.OrderLineItemParentOrderLineItemID === 0);

  return `
    <div class="order-card ${statusClass}">
      <div class="order-header">
        <div class="order-number">#${order.OrderID}</div>
        <div class="order-time">
          <div class="elapsed-time ${timeClass}">${formatElapsedTime(elapsedTime)}</div>
          <div class="submit-time">${formatSubmitTime(order.OrderSubmittedOn)}</div>
        </div>
      </div>

      <div class="order-info">
        <div><strong>Table:</strong> ${order.ServicePointName || 'N/A'}</div>
        <div><strong>Customer:</strong> ${order.UserFirstName || ''} ${order.UserLastName || ''}</div>
        <div><strong>Status:</strong> ${STATUS_NAMES[order.OrderStatusID] || 'Unknown'}</div>
      </div>

      ${order.OrderRemarks ? `<div class="order-remarks">Note: ${escapeHtml(order.OrderRemarks)}</div>` : ''}

      <div class="line-items">
        ${rootItems.map(item => renderLineItem(item, order.LineItems)).join('')}
      </div>

      <div class="action-buttons">
        ${renderActionButtons(order)}
      </div>
    </div>
  `;
}

// Render line item with modifiers
function renderLineItem(item, allItems) {
  const modifiers = allItems.filter(mod => mod.OrderLineItemParentOrderLineItemID === item.OrderLineItemID);

  console.log(`[renderLineItem] Item: ${item.ItemName}, ID: ${item.OrderLineItemID}, Modifiers found: ${modifiers.length}`);
  if (modifiers.length > 0) {
    console.log('[renderLineItem] Modifiers:', modifiers);
  }

  return `
    <div class="line-item">
      <div class="line-item-main">
        <div class="item-name">${escapeHtml(item.ItemName)}</div>
        <div class="item-qty">×${item.OrderLineItemQuantity}</div>
      </div>

      ${modifiers.length > 0 ? renderAllModifiers(modifiers, allItems) : ''}

      ${item.OrderLineItemRemark ? `
        <div class="item-remark">Note: ${escapeHtml(item.OrderLineItemRemark)}</div>
      ` : ''}
    </div>
  `;
}

// Render all modifiers (flattened, no nested wrappers)
function renderAllModifiers(modifiers, allItems) {
  let html = '<div class="modifiers">';

  // Build path for each leaf modifier
  function getModifierPath(mod) {
    const path = [];
    let current = mod;

    // Walk up the tree to build the path
    while (current) {
      path.unshift(current.ItemName);
      const parentId = current.OrderLineItemParentOrderLineItemID;
      if (parentId === 0) break;
      current = allItems.find(item => item.OrderLineItemID === parentId);
    }

    return path;
  }

  // Collect all leaf modifiers with their paths
  const leafModifiers = [];

  function collectLeafModifiers(mods) {
    mods.forEach(mod => {
      const children = allItems.filter(item => item.OrderLineItemParentOrderLineItemID === mod.OrderLineItemID);
      if (children.length === 0) {
        // This is a leaf - no children
        const path = getModifierPath(mod);
        leafModifiers.push({ mod, path });
      } else {
        // This has children, recurse into them
        collectLeafModifiers(children);
      }
    });
  }

  collectLeafModifiers(modifiers);

  // Render leaf modifiers with breadcrumb paths
  leafModifiers.forEach(({ path }) => {
    const displayText = path.join(': ');
    html += `<div class="modifier">+ ${escapeHtml(displayText)}</div>`;
  });

  html += '</div>';
  return html;
}

// Render modifier recursively with indentation
function renderModifierRecursive(modifier, allItems, level) {
  const subModifiers = allItems.filter(mod => mod.OrderLineItemParentOrderLineItemID === modifier.OrderLineItemID);
  // For KDS MVP: no indentation, just flat list
  const indent = 0; // Changed from: level * 20

  console.log(`[renderModifierRecursive] Level ${level}: ${modifier.ItemName} (ID: ${modifier.OrderLineItemID}), Sub-modifiers: ${subModifiers.length}`);

  let html = `<div class="modifier" style="padding-left: ${indent}px;">+ ${escapeHtml(modifier.ItemName)}</div>`;

  // Recursively render sub-modifiers
  if (subModifiers.length > 0) {
    subModifiers.forEach(sub => {
      html += renderModifierRecursive(sub, allItems, level + 1);
    });
  }

  return html;
}

// Render action buttons based on order status
function renderActionButtons(order) {
  switch (order.OrderStatusID) {
    case STATUS.NEW:
      return `<button class="btn btn-start" onclick="updateOrderStatus(${order.OrderID}, ${STATUS.PREPARING})">Start Preparing</button>`;

    case STATUS.PREPARING:
      return `<button class="btn btn-ready" onclick="updateOrderStatus(${order.OrderID}, ${STATUS.READY})">Mark as Ready</button>`;

    case STATUS.READY:
      return `<button class="btn btn-complete" onclick="updateOrderStatus(${order.OrderID}, ${STATUS.COMPLETED})">Complete</button>`;

    default:
      return '';
  }
}

// Update order status
async function updateOrderStatus(orderId, newStatusId) {
  try {
    const response = await fetch(`${config.apiBaseUrl}/orders/updateStatus.cfm`, {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
      },
      body: JSON.stringify({
        OrderID: orderId,
        StatusID: newStatusId
      })
    });

    const data = await response.json();

    if (data.OK) {
      // Immediately reload orders to reflect the change
      await loadOrders();
    } else {
      alert(`Failed to update order: ${data.MESSAGE || data.ERROR}`);
    }
  } catch (error) {
    console.error('Failed to update order status:', error);
    alert('Failed to update order status. Please try again.');
  }
}

// Helper functions
function getStatusClass(statusId) {
  switch (statusId) {
    case STATUS.NEW: return 'new';
    case STATUS.PREPARING: return 'preparing';
    case STATUS.READY: return 'ready';
    default: return '';
  }
}

function getElapsedTime(submittedOn) {
  if (!submittedOn) return 0;
  const submitted = new Date(submittedOn);
  const now = new Date();
  return Math.floor((now - submitted) / 1000); // seconds
}

function getTimeClass(seconds) {
  if (seconds > 900) return 'critical'; // > 15 min
  if (seconds > 600) return 'warning';  // > 10 min
  return '';
}

function formatElapsedTime(seconds) {
  const minutes = Math.floor(seconds / 60);
  const secs = seconds % 60;
  return `${minutes}:${secs.toString().padStart(2, '0')}`;
}

function formatSubmitTime(dateString) {
  if (!dateString) return '';
  const date = new Date(dateString);
  return date.toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' });
}

function escapeHtml(text) {
  const div = document.createElement('div');
  div.textContent = text;
  return div.innerHTML;
}