// DOM Elements
const queueTab = document.getElementById('queueTab');
const usersTab = document.getElementById('usersTab');
const cacheTab = document.getElementById('cacheTab');
const logoutButton = document.getElementById('logoutButton');

const queueSection = document.getElementById('queueSection');
const usersSection = document.getElementById('usersSection');
const cacheSection = document.getElementById('cacheSection');

const nowPlaying = document.getElementById('nowPlaying');
const queueList = document.getElementById('queueList');
const clearQueueButton = document.getElementById('clearQueueButton');

const usersTable = document.getElementById('usersTable');
const addUserButton = document.getElementById('addUserButton');
const addUserModal = document.getElementById('addUserModal');
const addUserForm = document.getElementById('addUserForm');
const cancelAddUser = document.getElementById('cancelAddUser');

const cacheSongCount = document.getElementById('cacheSongCount');
const cacheSize = document.getElementById('cacheSize');
const cacheMaxSize = document.getElementById('cacheMaxSize');
const cacheUsage = document.getElementById('cacheUsage');
const clearCacheButton = document.getElementById('clearCacheButton');

// Tab switching
function switchTab(tab, section) {
  // Remove active class from all tabs and sections
  [queueTab, usersTab, cacheTab].forEach(t => t.classList.remove('active'));
  [queueSection, usersSection, cacheSection].forEach(s => s.classList.remove('active'));
  
  // Add active class to selected tab and section
  tab.classList.add('active');
  section.classList.add('active');
}

queueTab.addEventListener('click', () => switchTab(queueTab, queueSection));
usersTab.addEventListener('click', () => switchTab(usersTab, usersSection));
cacheTab.addEventListener('click', () => switchTab(cacheTab, cacheSection));

// Logout
logoutButton.addEventListener('click', async () => {
  try {
    await fetch('/api/logout', {
      method: 'POST',
      credentials: 'include', // Important for cookies to work
    });
    window.location.href = '/login';
  } catch (error) {
    console.error('Logout failed:', error);
  }
});

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

async function loadQueue() {
  try {
    const response = await fetch('/api/queue', {
      credentials: 'include', // Important for cookies to work
    });
    const responseData = await response.json();
    
    // Update now playing
    if (responseData.current_song) {
      nowPlaying.innerHTML = `
        <div class="song-info">
          <h4>${responseData.current_song.title}</h4>
          <p>${formatDuration(responseData.current_song.duration)}</p>
        </div>
        <div class="song-status">
          <span class="badge">${responseData.state}</span>
        </div>
      `;
    } else {
      nowPlaying.innerHTML = '<p>Nothing playing</p>';
    }
    
    // Update queue
    if (responseData.queue && responseData.queue.length > 0) {
      queueList.innerHTML = responseData.queue.map((songItem, idx) => {
        if (songItem.is_current) {
          return `
            <li class="now-playing">
              <div class="song-info">
                <strong>${songItem.title}</strong>
                <span>${formatDuration(songItem.duration)}</span>
              </div>
              <div class="song-status">
                <span class="badge">Now Playing</span>
              </div>
            </li>
          `;
        } else {
          return `
            <li>
              <div class="song-info">
                <strong>${idx + 1}. ${songItem.title}</strong>
                <span>${formatDuration(songItem.duration)}</span>
              </div>
            </li>
          `;
        }
      }).join('');
    } else {
      queueList.innerHTML = '<li class="empty-message">Queue is empty</li>';
    }
  } catch (error) {
    console.error('Failed to load queue:', error);
    queueList.innerHTML = '<li class="empty-message">Failed to load queue</li>';
  }
}

clearQueueButton.addEventListener('click', async () => {
  if (!confirm('Are you sure you want to clear the queue?')) return;
  
  try {
    await fetch('/api/queue', {
      method: 'DELETE',
      credentials: 'include', // Important for cookies to work
    });
    loadQueue();
  } catch (error) {
    console.error('Failed to clear queue:', error);
    alert('Failed to clear queue');
  }
});

// User management
async function loadUsers() {
  try {
    const response = await fetch('/api/users', {
      credentials: 'include', // Important for cookies to work
    });
    const responseData = await response.json();
    
    if (responseData.users && responseData.users.length > 0) {
      const tbody = usersTable.querySelector('tbody');
      tbody.innerHTML = responseData.users.map(userItem => `
        <tr>
          <td>${userItem.username}</td>
          <td>
            <select class="permission-select" data-username="${userItem.username}">
              <option value="0" ${userItem.permission_level == 0 ? 'selected' : ''}>None</option>
              <option value="1" ${userItem.permission_level == 1 ? 'selected' : ''}>View Only</option>
              <option value="2" ${userItem.permission_level == 2 ? 'selected' : ''}>Read/Write</option>
              <option value="3" ${userItem.permission_level == 3 ? 'selected' : ''}>Admin</option>
            </select>
          </td>
          <td>
            <button class="save-permission" data-username="${userItem.username}">Save</button>
          </td>
        </tr>
      `).join('');
      
      // Add event listeners to save buttons
      document.querySelectorAll('.save-permission').forEach(button => {
        button.addEventListener('click', async () => {
          const username = button.dataset.username;
          const select = document.querySelector(`.permission-select[data-username="${username}"]`);
          const permissionLevel = parseInt(select.value);
          
          try {
            await fetch(`/api/users/${username}/permissions`, {
              method: 'PUT',
              headers: {
                'Content-Type': 'application/json',
                'Accept': 'application/json'
              },
              body: JSON.stringify({ permission_level: permissionLevel }),
              credentials: 'include', // Important for cookies to work
            });
            alert(`Permission updated for ${username}`);
          } catch (error) {
            console.error('Failed to update permission:', error);
            alert('Failed to update permission');
          }
        });
      });
    } else {
      usersTable.querySelector('tbody').innerHTML = '<tr class="empty-message"><td colspan="3">No users found</td></tr>';
    }
  } catch (error) {
    console.error('Failed to load users:', error);
    usersTable.querySelector('tbody').innerHTML = '<tr class="empty-message"><td colspan="3">Failed to load users</td></tr>';
  }
}

// Add user modal
addUserButton.addEventListener('click', () => {
  addUserModal.classList.add('active');
});

cancelAddUser.addEventListener('click', () => {
  addUserModal.classList.remove('active');
  addUserForm.reset();
});

addUserForm.addEventListener('submit', async (e) => {
  e.preventDefault();
  
  const username = document.getElementById('newUsername').value;
  const permissionLevel = parseInt(document.getElementById('newPermissionLevel').value);
  
  try {
    await fetch('/api/users', {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
      },
      body: JSON.stringify({ username, permission_level: permissionLevel }),
      credentials: 'include', // Important for cookies to work
    });
    
    addUserModal.classList.remove('active');
    addUserForm.reset();
    loadUsers();
  } catch (error) {
    console.error('Failed to add user:', error);
    alert('Failed to add user');
  }
});

// Cache management
async function loadCacheStats() {
  try {
    const response = await fetch('/api/cache', {
      credentials: 'include', // Important for cookies to work
      headers: {
        'Accept': 'application/json'
      }
    });
    const stats = await response.json();
    
    cacheSongCount.textContent = stats.songCount;
    cacheSize.textContent = `${stats.totalSizeMb} MB`;
    cacheMaxSize.textContent = `${stats.maxSizeMb} MB`;
    
    const usagePercent = stats.maxSizeMb > 0 
      ? (stats.totalSizeMb / stats.maxSizeMb) * 100 
      : 0;
    
    cacheUsage.style.width = `${Math.min(usagePercent, 100)}%`;
    
    // Change color based on usage
    if (usagePercent > 90) {
      cacheUsage.style.backgroundColor = 'var(--danger-color)';
    } else if (usagePercent > 70) {
      cacheUsage.style.backgroundColor = 'var(--accent-color)';
    } else {
      cacheUsage.style.backgroundColor = 'var(--primary-color)';
    }
  } catch (error) {
    console.error('Failed to load cache stats:', error);
  }
}

clearCacheButton.addEventListener('click', async () => {
  if (!confirm('Are you sure you want to clear the cache? This will delete all downloaded audio files.')) return;
  
  try {
    await fetch('/api/cache', {
      method: 'DELETE',
      credentials: 'include', // Important for cookies to work
    });
    loadCacheStats();
  } catch (error) {
    console.error('Failed to clear cache:', error);
    alert('Failed to clear cache');
  }
});

// Initial load
document.addEventListener('DOMContentLoaded', () => {
  loadQueue();
  loadUsers();
  loadCacheStats();
  
  // Refresh data periodically
  setInterval(loadQueue, 10000); // Every 10 seconds
  setInterval(loadCacheStats, 30000); // Every 30 seconds
});