/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is Geolocation.
 *
 * The Initial Developer of the Original Code is Mozilla Corporation
 * Portions created by the Initial Developer are Copyright (C) 2008
 * the Initial Developer. All Rights Reserved.
 *
 * This is a derivative of work done by Google under a BSD style License.
 * See: http://gears.googlecode.com/svn/trunk/gears/geolocation/
 *
 * Contributor(s):
 *  Doug Turner <dougt@meer.net>  (Original Author)
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */


#include "windows.h"
#include "wlanapi.h"

#include <ntddndis.h>
#include "winioctl.h"


#include "nsAutoPtr.h"
#include "nsWifiMonitor.h"
#include "nsWifiAccessPoint.h"

#include "nsIProxyObjectManager.h"
#include "nsServiceManagerUtils.h"
#include "nsComponentManagerUtils.h"
#include "nsIMutableArray.h"


// Taken from ndis.h
#define NDIS_STATUS_INVALID_LENGTH   ((NDIS_STATUS)0xC0010014L)
#define NDIS_STATUS_BUFFER_TOO_SHORT ((NDIS_STATUS)0xC0010016L)

static const int kStringLength = 512;

// The limits on the size of the buffer used for the OID query.
static const int kInitialBufferSize = 2 << 12;  // Good for about 50 APs.
static const int kMaximumBufferSize = 2 << 20;  // 2MB

static int oid_buffer_size_ = kStringLength;

PRBool ResizeBuffer(int requested_size, BYTE **buffer)
{
  if (requested_size > kMaximumBufferSize) {
    free(*buffer);
    *buffer = NULL;
    return false;
  }

  BYTE *new_buffer = reinterpret_cast<BYTE*>(realloc(*buffer, requested_size));
  if (new_buffer == NULL) {
    free(*buffer);
    *buffer = NULL;
    return false;
  }

  *buffer = new_buffer;
  return true;
}



int PerformQuery(HANDLE adapter_handle,
                 BYTE *buffer,
                 DWORD buffer_size,
                 DWORD *bytes_out) {

  DWORD oid = OID_802_11_BSSID_LIST;
  
  if (!DeviceIoControl(adapter_handle,
                       IOCTL_NDIS_QUERY_GLOBAL_STATS,
                       &oid,
                       sizeof(oid),
                       buffer,
                       buffer_size,
                       bytes_out,
                       NULL)) {
    return GetLastError();
  }
  return ERROR_SUCCESS;
}

HANDLE GetFileHandle(const unsigned short* device_name) {
  // We access a device with DOS path \Device\<device_name> at
  // \\.\<device_name>. 

  nsString formatted_device_name;
  formatted_device_name.Assign(L"\\\\.\\");
  formatted_device_name.Append(device_name);

  return CreateFileW(formatted_device_name.get(),
                     GENERIC_READ,
                     FILE_SHARE_READ | FILE_SHARE_WRITE, // share mode
                     0,  // security attributes
                     OPEN_EXISTING,
                     0,  // flags and attributes
                     INVALID_HANDLE_VALUE);
}


bool UndefineDosDevice(const unsigned short* device_name) {
  // We remove only the mapping we use, that is \Device\<device_name>.
  nsString target_path;
  target_path.Assign(L"\\Device\\");
  target_path.Append(device_name);

  return DefineDosDeviceW(DDD_RAW_TARGET_PATH | DDD_REMOVE_DEFINITION | DDD_EXACT_MATCH_ON_REMOVE,
                          device_name,
                          target_path.get()) == TRUE;
}

bool DefineDosDeviceIfNotExists(unsigned short* device_name) {

  // We create a DOS device name for the device at \Device\<device_name>.
  nsString target_path;
  target_path.Assign(L"\\Device\\");
  target_path.Append(device_name);

  unsigned short target[kStringLength];

  if (QueryDosDeviceW(device_name, target, kStringLength) > 0 && target_path.Equals(target)) {     
    // Device already exists.
    return true;
  } 

  DWORD error = GetLastError();
  if (error != ERROR_FILE_NOT_FOUND) {
    return false;
  }

  if (!DefineDosDeviceW(DDD_RAW_TARGET_PATH,
                        device_name,
                        target_path.get())) {
    return false;
  }
  // Check that the device is really there. 
  return QueryDosDeviceW(device_name, target, kStringLength) > 0 &&
    target_path.Equals(target);
} 

void GetNetworkInterfacesFromRegistry(nsStringArray& interfaces)
{
  HKEY network_cards_key = NULL;
  if (RegOpenKeyExW(HKEY_LOCAL_MACHINE,
                    L"Software\\Microsoft\\Windows NT\\CurrentVersion\\NetworkCards",
                    0,
                    KEY_READ,
                    &network_cards_key) != ERROR_SUCCESS)
    {
      return;
    }   
  
  for (int i = 0; ; ++i) {
    unsigned short name[kStringLength];
    DWORD name_size = kStringLength;
    FILETIME time;
    
    if (RegEnumKeyExW(network_cards_key,
                      i,
                      name,
                      &name_size,
                      NULL,
                      NULL,
                      NULL,
                      &time) != ERROR_SUCCESS) 
      {
        break;
      }     
    
    HKEY hardware_key = NULL;
    if (RegOpenKeyExW(network_cards_key,
                      name,
                      0,
                      KEY_READ,
                      &hardware_key) != ERROR_SUCCESS)
      {
        break;
      }
    
    unsigned short service_name[kStringLength];
    DWORD service_name_size = kStringLength;
    DWORD type = 0;
    
    if (RegQueryValueExW(hardware_key,
                         L"ServiceName",
                         NULL,
                         &type,
                         reinterpret_cast<LPBYTE>(service_name),
                         &service_name_size) == ERROR_SUCCESS) {
 
      interfaces.AppendString(nsString(service_name));  // is this allowed?
    } 
    RegCloseKey(hardware_key);
  }
  RegCloseKey(network_cards_key);
}


PRBool IsRunningOnVista() {
  static DWORD os_major_version = 0;
  static DWORD platform_id = 0;

  if (0 == os_major_version) {
    OSVERSIONINFO os_version = {0};
    os_version.dwOSVersionInfoSize = sizeof(os_version);
    GetVersionEx(&os_version);
    os_major_version = os_version.dwMajorVersion;
    platform_id = os_version.dwPlatformId;
  }

  return (6 == os_major_version) && (VER_PLATFORM_WIN32_NT == platform_id);
}

nsresult
nsWifiMonitor::DoScan()
{
  if (!IsRunningOnVista()) {

    nsCOMArray<nsWifiAccessPoint> lastAccessPoints;
    nsCOMArray<nsWifiAccessPoint> accessPoints;
    
    do {
      accessPoints.Clear();

      nsStringArray interfaces;
      GetNetworkInterfacesFromRegistry(interfaces);
      
      for (int i = 0; i < interfaces.Count(); i++) {
        nsString *s = interfaces.StringAt(i);
        unsigned short *service_name = (PRUnichar*) s->get();
        
        if (!DefineDosDeviceIfNotExists(service_name))
          continue;

        // Get the handle to the device. This will fail if the named device is not
        // valid.
        
        HANDLE adapter_handle = GetFileHandle(service_name);
        if (adapter_handle == INVALID_HANDLE_VALUE)
          continue;

        // Get the data.
        
        BYTE *buffer = reinterpret_cast<BYTE*>(malloc(oid_buffer_size_));
        if (buffer == NULL)
          return NS_ERROR_OUT_OF_MEMORY;
          
        DWORD bytes_out;
        int result;
        
        while (true) {     
          bytes_out = 0; 
          result = PerformQuery(adapter_handle, buffer, oid_buffer_size_, &bytes_out);
          
          if (result == ERROR_GEN_FAILURE ||  // Returned by some Intel cards.
              result == ERROR_INSUFFICIENT_BUFFER ||
              result == ERROR_MORE_DATA ||
              result == NDIS_STATUS_INVALID_LENGTH ||
              result == NDIS_STATUS_BUFFER_TOO_SHORT) {
            
            // The buffer we supplied is too small, so increase it. bytes_out should 
            // provide the required buffer size, but this is not always the case. 
            
            if (bytes_out > static_cast<DWORD>(oid_buffer_size_)) { 
              oid_buffer_size_ = bytes_out;
            } else {
              oid_buffer_size_ *= 2;
            } 
            
            if (!ResizeBuffer(oid_buffer_size_, &buffer)) {
              oid_buffer_size_ = kInitialBufferSize;  // Reset for next time. 
              continue;
            }
          } else {
            // The buffer is not too small.
            break;
          }
        }
          
        if (result == ERROR_SUCCESS) {
          NDIS_802_11_BSSID_LIST* bssid_list = reinterpret_cast<NDIS_802_11_BSSID_LIST*>(buffer);
          
          // Walk through the BSS IDs.
          int found = 0;
          const uint8 *iterator = reinterpret_cast<const uint8*>(&bssid_list->Bssid[0]);
          const uint8 *end_of_buffer = reinterpret_cast<const uint8*>(&bssid_list) + oid_buffer_size_;
          for (int i = 0; i < static_cast<int>(bssid_list->NumberOfItems); ++i) {
            
            const NDIS_WLAN_BSSID *bss_id = reinterpret_cast<const NDIS_WLAN_BSSID*>(iterator);
            
            // Check that the length of this BSS ID is reasonable.
            if (bss_id->Length < sizeof(NDIS_WLAN_BSSID) ||
                iterator + bss_id->Length > end_of_buffer) {
              break;
            }
            
            nsWifiAccessPoint* ap = new nsWifiAccessPoint();
            if (!ap)
              continue;
            
            ap->setMac(bss_id->MacAddress);
            ap->setSignal(bss_id->Rssi);
            ap->setSSID((char*) bss_id->Ssid.Ssid, bss_id->Ssid.SsidLength);
            
            accessPoints.AppendObject(ap);
            
            // Move to the next BSS ID.
            iterator += bss_id->Length;
          }

          free(buffer); 

          // Clean up.
          CloseHandle(adapter_handle);
        }
        
        UndefineDosDevice(service_name);
      }
     
 
    
    PRBool accessPointsChanged = !AccessPointsEqual(accessPoints, lastAccessPoints);
    nsCOMArray<nsIWifiListener> currentListeners;
    
    {
      nsAutoMonitor mon(mMonitor);
      
      for (PRUint32 i = 0; i < mListeners.Length(); i++) {
        if (!mListeners[i].mHasSentData || accessPointsChanged) {
          mListeners[i].mHasSentData = PR_TRUE;
          currentListeners.AppendObject(mListeners[i].mListener);
        }
      }
    }
    
    ReplaceArray(lastAccessPoints, accessPoints);
    
    if (currentListeners.Count() > 0) {

      PRUint32 resultCount = lastAccessPoints.Count();
      nsIWifiAccessPoint** result = static_cast<nsIWifiAccessPoint**> (nsMemory::Alloc(sizeof(nsIWifiAccessPoint*) * resultCount));
      if (!result)
        return NS_ERROR_OUT_OF_MEMORY;
      
      for (PRUint32 i = 0; i < resultCount; i++)
        result[i] = lastAccessPoints[i];
      
      for (PRInt32 i = 0; i < currentListeners.Count(); i++) {
          
        LOG(("About to send data to the wifi listeners\n"));
        
        nsCOMPtr<nsIWifiListener> proxy;
        nsCOMPtr<nsIProxyObjectManager> proxyObjMgr = do_GetService("@mozilla.org/xpcomproxy;1");
        proxyObjMgr->GetProxyForObject(NS_PROXY_TO_MAIN_THREAD,
                                       NS_GET_IID(nsIWifiListener),
                                       currentListeners[i],
                                       NS_PROXY_SYNC | NS_PROXY_ALWAYS,
                                       getter_AddRefs(proxy));
        if (!proxy) {
          LOG(("There is no proxy available.  this should never happen\n"));
        }
        else
        {
          nsresult rv = proxy->OnChange(result, resultCount);
          LOG( ("... sent %d\n", rv));
        }
      }

      nsMemory::Free(result);
    }
    
    // wait for some reasonable amount of time.  pref?
    LOG(("waiting on monitor\n"));
    
    nsAutoMonitor mon(mMonitor);
    mon.Wait(PR_SecondsToInterval(60));
  }
  while (mKeepGoing == PR_TRUE);



  }
  else {

    HINSTANCE wlan_library = LoadLibrary("Wlanapi.dll");
    if (!wlan_library)
      return NS_ERROR_NOT_AVAILABLE;
    
    WlanOpenHandleFunction WlanOpenHandle = (WlanOpenHandleFunction) GetProcAddress(wlan_library, "WlanOpenHandle");
    WlanEnumInterfacesFunction WlanEnumInterfaces = (WlanEnumInterfacesFunction) GetProcAddress(wlan_library, "WlanEnumInterfaces");
    WlanGetNetworkBssListFunction WlanGetNetworkBssList = (WlanGetNetworkBssListFunction) GetProcAddress(wlan_library, "WlanGetNetworkBssList");
    WlanFreeMemoryFunction WlanFreeMemory = (WlanFreeMemoryFunction) GetProcAddress(wlan_library, "WlanFreeMemory");
    WlanCloseHandleFunction WlanCloseHandle = (WlanCloseHandleFunction) GetProcAddress(wlan_library, "WlanCloseHandle");
    
    if (!WlanOpenHandle ||
        !WlanEnumInterfaces ||
        !WlanGetNetworkBssList ||
        !WlanFreeMemory ||
        !WlanCloseHandle)
      return NS_ERROR_FAILURE;
    
    // Regularly get the access point data.
    
    nsCOMArray<nsWifiAccessPoint> lastAccessPoints;
    nsCOMArray<nsWifiAccessPoint> accessPoints;
    
    do {
      accessPoints.Clear();
      
      // Get the handle to the WLAN API.
      DWORD negotiated_version;
      HANDLE wlan_handle = NULL;
      // We could be executing on either Windows XP or Windows Vista, so use the
      // lower version of the client WLAN API. It seems that the negotiated version
      // is the Vista version irrespective of what we pass!
      static const int kXpWlanClientVersion = 1;
      if ((*WlanOpenHandle)(kXpWlanClientVersion,
                            NULL,
                            &negotiated_version,
                            &wlan_handle) != ERROR_SUCCESS) {
        return NS_ERROR_NOT_AVAILABLE;
      }
      
      // try again later.
      if (!wlan_handle)
        return NS_ERROR_FAILURE;
      
      // Get the list of interfaces. WlanEnumInterfaces allocates interface_list.
      WLAN_INTERFACE_INFO_LIST *interface_list = NULL;
      if ((*WlanEnumInterfaces)(wlan_handle, NULL, &interface_list) != ERROR_SUCCESS) {
        // try again later
        (*WlanCloseHandle)(wlan_handle, NULL);
        return NS_ERROR_FAILURE;
      }
      
      // Go through the list of interfaces and get the data for each.
      for (int i = 0; i < static_cast<int>(interface_list->dwNumberOfItems); ++i) {
        
        WLAN_BSS_LIST *bss_list;
        HRESULT rv = (*WlanGetNetworkBssList)(wlan_handle,
                                              &interface_list->InterfaceInfo[i].InterfaceGuid,
                                              NULL,   // Use all SSIDs.
                                              DOT11_BSS_TYPE_UNUSED,
                                              false,  // bSecurityEnabled - unused
                                              NULL,   // reserved
                                              &bss_list);
        if (rv != ERROR_SUCCESS) {
          continue;
        }
        
        for (int j = 0; j < static_cast<int>(bss_list->dwNumberOfItems); ++j) {
          
          nsWifiAccessPoint* ap = new nsWifiAccessPoint();
          if (!ap)
            continue;
          
          const WLAN_BSS_ENTRY bss_entry = bss_list->wlanBssEntries[j];
          
          ap->setMac(bss_entry.dot11Bssid);
          ap->setSignal(bss_entry.lRssi);
          ap->setSSID((char*) bss_entry.dot11Ssid.ucSSID,
                      bss_entry.dot11Ssid.uSSIDLength);
          
          accessPoints.AppendObject(ap);
        }
        (*WlanFreeMemory)(bss_list);
      }
      
      // Free interface_list.
      (*WlanFreeMemory)(interface_list);
      
      // Close the handle.
      (*WlanCloseHandle)(wlan_handle, NULL);
      
      
      PRBool accessPointsChanged = !AccessPointsEqual(accessPoints, lastAccessPoints);
      nsCOMArray<nsIWifiListener> currentListeners;
      
      {
        nsAutoMonitor mon(mMonitor);
      
        for (PRUint32 i = 0; i < mListeners.Length(); i++) {
          if (!mListeners[i].mHasSentData || accessPointsChanged) {
            mListeners[i].mHasSentData = PR_TRUE;
            currentListeners.AppendObject(mListeners[i].mListener);
          }
        }
      }
      
      ReplaceArray(lastAccessPoints, accessPoints);
      
      if (currentListeners.Count() > 0) {
        PRUint32 resultCount = lastAccessPoints.Count();
        nsIWifiAccessPoint** result = static_cast<nsIWifiAccessPoint**> (nsMemory::Alloc(sizeof(nsIWifiAccessPoint*) * resultCount));
        if (!result)
          return NS_ERROR_OUT_OF_MEMORY;
      
        for (PRUint32 i = 0; i < resultCount; i++)
          result[i] = lastAccessPoints[i];
        
        for (PRInt32 i = 0; i < currentListeners.Count(); i++) {
          
          LOG(("About to send data to the wifi listeners\n"));
          
          nsCOMPtr<nsIWifiListener> proxy;
          nsCOMPtr<nsIProxyObjectManager> proxyObjMgr = do_GetService("@mozilla.org/xpcomproxy;1");
          proxyObjMgr->GetProxyForObject(NS_PROXY_TO_MAIN_THREAD,
                                         NS_GET_IID(nsIWifiListener),
                                         currentListeners[i],
                                         NS_PROXY_SYNC | NS_PROXY_ALWAYS,
                                         getter_AddRefs(proxy));
          if (!proxy) {
            LOG(("There is no proxy available.  this should never happen\n"));
          }
          else
          {
            nsresult rv = proxy->OnChange(result, resultCount);
            LOG( ("... sent %d\n", rv));
          }
        }
        
        nsMemory::Free(result);
      }
      
      // wait for some reasonable amount of time.  pref?
      LOG(("waiting on monitor\n"));
      
      nsAutoMonitor mon(mMonitor);
      mon.Wait(PR_SecondsToInterval(60));
    }
    while (mKeepGoing == PR_TRUE);
  }
  return NS_OK;
}