webdrop-bridge/src/webdrop_bridge/ui/bridge_script_intercept.js

// WebDrop Bridge - Intercept Version
// Prevents browser drag for ALT+drag, hands off to Qt for file drag

(function() {
  try {
    if (window.__webdrop_intercept_injected) return;
    window.__webdrop_intercept_injected = true;

    // Intercept mode enabled
    var INTERCEPT_ENABLED = true;

    console.log('%c[WebDrop Intercept] Script loaded - INTERCEPT_ENABLED=' + INTERCEPT_ENABLED, 'background: #2196F3; color: white; font-weight: bold; padding: 4px 8px;');
    
    var currentDragUrl = null;
    var angularDragHandlers = [];
    var originalAddEventListener = EventTarget.prototype.addEventListener;
    var listenerPatchActive = true;
    
    // Capture Authorization token from XHR requests
    window.capturedAuthToken = null;
    var originalXHRSetRequestHeader = XMLHttpRequest.prototype.setRequestHeader;
    XMLHttpRequest.prototype.setRequestHeader = function(header, value) {
      if (header === 'Authorization' && value.startsWith('Bearer ')) {
        window.capturedAuthToken = value;
        console.log('[Intercept] Captured auth token');
      }
      return originalXHRSetRequestHeader.apply(this, arguments);
    };
  
  // ============================================================================
  // PART 1: Intercept Angular's dragstart listener registration
  // ============================================================================
  
  EventTarget.prototype.addEventListener = function(type, listener, options) {
    if (listenerPatchActive && type === 'dragstart' && listener) {
      // Store Angular's dragstart handler instead of registering it
      console.log('[Intercept] Storing Angular dragstart listener for', this.tagName || this.constructor.name);
      angularDragHandlers.push({
        target: this,
        listener: listener,
        options: options
      });
      return; // Don't actually register it yet
    }
    // All other events: use original
    return originalAddEventListener.call(this, type, listener, options);
  };
  
  // ============================================================================
  // PART 2: Intercept DataTransfer.setData to capture URL
  // ============================================================================
  
  var originalSetData = DataTransfer.prototype.setData;
  
  DataTransfer.prototype.setData = function(format, data) {
    if (format === 'text/plain' || format === 'text/uri-list') {
      currentDragUrl = data;
      console.log('%c[Intercept] Captured URL:', 'color: #4CAF50; font-weight: bold;', data.substring(0, 80));
    }
    return originalSetData.call(this, format, data);
  };
  
  console.log('[Intercept] DataTransfer.setData patched ✓');
  
  // ============================================================================
  // PART 3: Install OUR dragstart handler in capture phase
  // ============================================================================
  
  function installDragHandler() {
    console.log('[Intercept] Installing dragstart handler, have', angularDragHandlers.length, 'Angular handlers');
    
    if (angularDragHandlers.length === 0) {
      console.warn('[Intercept] No Angular handlers found yet, will retry in 1s...');
      setTimeout(installDragHandler, 1000);
      return;
    }
    
    // Stop intercepting addEventListener
    listenerPatchActive = false;
    
    // Register OUR handler in capture phase
    originalAddEventListener.call(document, 'dragstart', function(e) {
      currentDragUrl = null; // Reset
      
      // Check once per drag if native DnD is disabled via URL param (e.g. ?disablednd=true)
      var disabledNativeDnD = /[?&]disablednd=true/i.test(window.location.search);
      console.log('%c[Intercept] dragstart', 'background: #FF9800; color: white; padding: 2px 6px;', 'ALT:', e.altKey, '| disablednd:', disabledNativeDnD);
      
      // Call Angular's handlers first to let them set the data
      var handled = 0;
      for (var i = 0; i < angularDragHandlers.length; i++) {
        var h = angularDragHandlers[i];
        if (h.target === document || h.target === e.target || 
            (h.target.contains && h.target.contains(e.target))) {
          try {
            h.listener.call(e.target, e);
            handled++;
          } catch(err) {
            console.error('[Intercept] Error calling Angular handler:', err);
          }
        }
      }
      
      console.log('[Intercept] Called', handled, 'Angular handlers, URL:', currentDragUrl ? currentDragUrl.substring(0, 60) : 'none');
      
      // NOW check if we should intercept
      // Intercept when: Alt key held (normal mode) OR native DnD disabled via URL param
      if ((e.altKey || disabledNativeDnD) && currentDragUrl) {
        var shouldIntercept = false;
        
        // Check against configured URL mappings
        if (window.webdropConfig && window.webdropConfig.urlMappings) {
          for (var j = 0; j < window.webdropConfig.urlMappings.length; j++) {
            var mapping = window.webdropConfig.urlMappings[j];
            if (currentDragUrl.toLowerCase().startsWith(mapping.url_prefix.toLowerCase())) {
              shouldIntercept = true;
              console.log('[Intercept] URL matches mapping for:', mapping.local_path);
              break;
            }
          }
        } else {
          // Fallback: Check for legacy Z: drive pattern if no config available
          shouldIntercept = /^z:/i.test(currentDragUrl);
          if (shouldIntercept) {
            console.warn('[Intercept] Using fallback Z: drive pattern (no URL mappings configured)');
          }
        }
        
        if (shouldIntercept) {
          console.log('%c[Intercept] PREVENTING browser drag, using Qt', 
                      'background: #F44336; color: white; font-weight: bold; padding: 4px 8px;');
          
          e.preventDefault();
          e.stopPropagation();
          
          ensureChannel(function() {
            if (window.bridge && typeof window.bridge.start_file_drag === 'function') {
              console.log('%c[Intercept] → Qt: start_file_drag', 'color: #9C27B0; font-weight: bold;');
              window.bridge.start_file_drag(currentDragUrl);
            } else {
              console.error('[Intercept] bridge.start_file_drag not available!');
            }
          });
          
          currentDragUrl = null;
          return false;
        }
      }
      
      console.log('[Intercept] Normal drag, allowing browser');
    }, true); // Capture phase
    
    console.log('[Intercept] dragstart handler installed ✓');
  }
  
  // Wait for Angular to register its listeners, then install our handler
  // Start checking after 2 seconds (give Angular time to load on first page load)
  setTimeout(installDragHandler, 2000);
  
  // ============================================================================
  // PART 3: QWebChannel connection
  // ============================================================================
  
  function ensureChannel(callback) {
    if (window.bridge) {
      callback();
      return;
    }
    
    if (window.QWebChannel && window.qt && window.qt.webChannelTransport) {
      new QWebChannel(window.qt.webChannelTransport, function(channel) {
        window.bridge = channel.objects.bridge;
        console.log('[WebDrop Intercept] QWebChannel connected ✓');
        callback();
      });
    } else {
      console.error('[WebDrop Intercept] QWebChannel not available!');
    }
  }
  
  // Initialize channel on load
  if (document.readyState === 'loading') {
    document.addEventListener('DOMContentLoaded', function() {
      ensureChannel(function() {
        console.log('[WebDrop Intercept] Bridge ready ✓');
      });
    });
  } else {
    ensureChannel(function() {
      console.log('[WebDrop Intercept] Bridge ready ✓');
    });
  }
  
  console.log('%c[WebDrop Intercept] Ready! ALT-drag or ?disablednd=true will use Qt file drag.', 
              'background: #4CAF50; color: white; font-weight: bold; padding: 4px 8px;');
  } catch(e) {
    console.error('[WebDrop Intercept] FATAL ERROR in bridge script:', e);
    console.error('[WebDrop Intercept] Stack:', e.stack);
  }
})();