/* -*- Mode: C++; tab-width: 3; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 *
 * 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 the Mozilla browser.
 * 
 * The Initial Developer of the Original Code is Netscape
 * Communications, Inc.  Portions created by Netscape are
 * Copyright (C) 1999, Mozilla.  All Rights Reserved.
 * 
 * Contributor(s):
 *   Scott MacGregor <mscott@netscape.com>
 */

#include "nsOSHelperAppService.h"
#include "nsISupports.h"
#include "nsString.h"
#include "nsXPIDLString.h"
#include "nsIURL.h"
#include "nsIMIMEInfo.h"
#include "nsMimeTypes.h"
#include "nsILocalFile.h"

// we need windows.h to read out registry information...
#include <windows.h>

// helper methods: forward declarations...
BYTE * GetValueBytes( HKEY hKey, const char *pValueName);
nsresult GetExtensionFrom4xRegistryInfo(const char * aMimeType, nsCString& aFileExtension);
nsresult GetExtensionFromWindowsMimeDatabase(const char * aMimeType, nsCString& aFileExtension);

nsOSHelperAppService::nsOSHelperAppService() : nsExternalHelperAppService()
{}

nsOSHelperAppService::~nsOSHelperAppService()
{}


NS_IMETHODIMP nsOSHelperAppService::CanHandleContent(const char *aMimeContentType, nsIURI * aURI, PRBool * aCanHandleContent)
{
  // once we have user over ride stuff working, we need to first call up to our base class
  // and ask the base class if we can handle the content. This will take care of looking for user specified 
  // apps for content types.

  *aCanHandleContent = PR_FALSE;
  nsresult rv = nsExternalHelperAppService::CanHandleContent(aMimeContentType, aURI,aCanHandleContent);

  if (NS_FAILED(rv) || *aCanHandleContent == PR_FALSE)
  {

  }
  return NS_OK;
}

NS_IMETHODIMP nsOSHelperAppService::DoContent(const char *aMimeContentType, nsIURI *aURI, nsISupports *aWindowContext, 
                                                    PRBool *aAbortProcess, nsIStreamListener ** aStreamListener)
{
  nsresult rv = NS_OK;

  // see if we have user specified information for handling this content type by giving the base class
  // first crack at it...

  rv = nsExternalHelperAppService::DoContent(aMimeContentType, aURI, aWindowContext, aAbortProcess, aStreamListener);
  
  // this is important!! if do content for the base class returned any success code, then assume we are done
  // and don't even play around with 
  if (NS_SUCCEEDED(rv)) return NS_OK;

  // okay the base class couldn't do anything so now it's our turn!!!
  // reset our rv value.
  rv = NS_OK;

  // ACK!!! we've done all this work to discover the content type just to find out that windows
  // registery uses the extension to figure out the right helper app....that's a bummer...
  // now we need to try to get the extension for the content type...

  nsCOMPtr<nsIMIMEInfo> mimeInfo;
  nsXPIDLCString fileExtension;

  GetFromMIMEType(aMimeContentType, getter_AddRefs(mimeInfo));

  // here's a nifty little trick. If we got a match back for the content type; but the content type is
  // unknown or octet (both of these are pretty much unhelpful mime objects), then see if the file extension
  // produces a better mime object...
  if (((nsCRT::strcmp(aMimeContentType, UNKNOWN_CONTENT_TYPE) == 0) ||
       (nsCRT::strcmp(aMimeContentType, APPLICATION_OCTET_STREAM) == 0) || 
       !mimeInfo))
  {
    // if we couldn't find one, don't give up yet! Try and see if there is an extension in the 
    // url itself...
    nsCOMPtr<nsIURL> url = do_QueryInterface(aURI);

    if (url)
    {
      url->GetFileExtension(getter_Copies(fileExtension));    
      nsCOMPtr<nsIMIMEInfo> tempMIMEObject;
      GetFromExtension(fileExtension, getter_AddRefs(tempMIMEObject));
      // only over write mimeInfo if we got a non-null temp mime info object.
      if (tempMIMEObject)
        mimeInfo = tempMIMEObject;
    }
  }

  if (!mimeInfo)
  {
    // if we didn't get a mime info object then the OS knows nothing about this mime type and WE know nothing about this mime type
    // so create a new mime info object and use it....
    mimeInfo = do_CreateInstance(NS_MIMEINFO_CONTRACTID);
    if (mimeInfo)
    {
      // the file extension was conviently already filled in by our call to FindOSMimeInfoForType.
      mimeInfo->SetFileExtensions(fileExtension);
      mimeInfo->SetMIMEType(aMimeContentType);
      // we may need to add a new method to nsIMIMEService so we can add this mime info object to our mime service.
    }
  }

  *aStreamListener = nsnull;
  if (NS_SUCCEEDED(rv) && mimeInfo)
  {
    // ensure that the file extension field is always filled in
    mimeInfo->FirstExtension(getter_Copies(fileExtension));

    // this code is incomplete and just here to get things started..
    nsExternalAppHandler * handler = CreateNewExternalHandler(mimeInfo, fileExtension, aWindowContext);
    handler->QueryInterface(NS_GET_IID(nsIStreamListener), (void **) aStreamListener);
  }

  return rv;
}

NS_IMETHODIMP nsOSHelperAppService::LaunchAppWithTempFile(nsIMIMEInfo * aMIMEInfo, nsIFile * aTempFile)
{
  nsresult rv = NS_OK;

  if (aMIMEInfo)
  {
    nsCOMPtr<nsIFile> application;
    nsXPIDLCString path;
    aTempFile->GetPath(getter_Copies(path));

    nsMIMEInfoHandleAction action = nsIMIMEInfo::useSystemDefault;
    aMIMEInfo->GetPreferredAction(&action);
    
    aMIMEInfo->GetPreferredApplicationHandler(getter_AddRefs(application));
    if (application && action == nsIMIMEInfo::useHelperApp)
    {
      // if we were given an application to use then use it....otherwise
      // make the registry call to launch the app
      const char * strPath = (const char *) path;
      application->Spawn(&strPath, 1);
    }    
    else // use the system default
    {
      // use the app registry name to launch a shell execute....
      LONG r = (LONG) ::ShellExecute( NULL, "open", (const char *) path, NULL, NULL, SW_SHOWNORMAL);
      if (r < 32) 
        rv = NS_ERROR_FAILURE;
			else
			  rv = NS_OK;
    }
  }

  return rv;
}

// The windows registry provides a mime database key which lists a set of mime types and corresponding "Extension" values. 
// we can use this to look up our mime type to see if there is a preferred extension for the mime type.
nsresult GetExtensionFromWindowsMimeDatabase(const char * aMimeType, nsCString& aFileExtension)
{
   nsresult rv = NS_OK;
   HKEY hKey;
   nsCAutoString mimeDatabaseKey ("MIME\\Database\\Content Type\\");

   mimeDatabaseKey += aMimeType;
   
   LONG err = ::RegOpenKeyEx( HKEY_CLASSES_ROOT, mimeDatabaseKey, 0, KEY_QUERY_VALUE, &hKey);
   if (err == ERROR_SUCCESS)
   {
      LPBYTE pBytes = GetValueBytes( hKey, "Extension");
      if (pBytes)
      { 
        aFileExtension = (char * )pBytes;
      }

      delete pBytes;

      ::RegCloseKey(hKey);
   }

   return NS_OK;

}

// We have a serious problem!! I have this content type and the windows registry only gives me
// helper apps based on extension. Right now, we really don't have a good place to go for 
// trying to figure out the extension for a particular mime type....One short term hack is to look
// this information in 4.x (it's stored in the windows regsitry). 
nsresult GetExtensionFrom4xRegistryInfo(const char * aMimeType, nsCString& aFileExtension)
{
   nsCAutoString command ("Software\\Netscape\\Netscape Navigator\\Suffixes");
   nsresult rv = NS_OK;
   HKEY hKey;
   LONG err = ::RegOpenKeyEx( HKEY_CURRENT_USER, command, 0, KEY_QUERY_VALUE, &hKey);
   if (err == ERROR_SUCCESS)
   {
      LPBYTE pBytes = GetValueBytes( hKey, aMimeType);
      if (pBytes) // only try to get the extension if we have a value!
      {
        aFileExtension = ".";
        aFileExtension.Append( (char *) pBytes);
      
        // this may be a comma separate list of extensions...just take the first one
        // for now...

        PRInt32 pos = aFileExtension.FindChar(',', PR_TRUE);
        if (pos > 0) // we have a comma separated list of languages...
          aFileExtension.Truncate(pos); // truncate everything after the first comma (including the comma)
      }
   
      delete [] pBytes;
      // close the key
      ::RegCloseKey(hKey);
   }
   else
     rv = NS_ERROR_FAILURE; // no 4.x extension mapping found!

   return rv;
}

BYTE * GetValueBytes( HKEY hKey, const char *pValueName)
{
	LONG	err;
	DWORD	bufSz;
	LPBYTE	pBytes = NULL;

	err = ::RegQueryValueEx( hKey, pValueName, NULL, NULL, NULL, &bufSz); 
	if (err == ERROR_SUCCESS) {
		pBytes = new BYTE[bufSz];
		err = ::RegQueryValueEx( hKey, pValueName, NULL, NULL, pBytes, &bufSz);
		if (err != ERROR_SUCCESS) {
			delete [] pBytes;
			pBytes = NULL;
		}
	}

	return( pBytes);
}

NS_IMETHODIMP nsOSHelperAppService::ExternalProtocolHandlerExists(const char * aProtocolScheme, PRBool * aHandlerExists)
{
  // look up the protocol scheme in the windows registry....if we find a match then we have a handler for it...
  *aHandlerExists = PR_FALSE;
  if (aProtocolScheme && *aProtocolScheme)
  {
     HKEY hKey;
     LONG err = ::RegOpenKeyEx( HKEY_CLASSES_ROOT, aProtocolScheme, 0, KEY_QUERY_VALUE, &hKey);
     if (err == ERROR_SUCCESS)
     {
       *aHandlerExists = PR_TRUE;
       // close the key
       ::RegCloseKey(hKey);
     }
  }

  return NS_OK;
}

// this implementation was pretty much copied verbatime from Tony Robinson's code in nsExternalProtocolWin.cpp

NS_IMETHODIMP nsOSHelperAppService::LoadUrl(nsIURI * aURL)
{
	nsresult rv = NS_OK;

	// 1. Find the default app for this protocol
	// 2. Set up the command line
	// 3. Launch the app.

	// For now, we'll just cheat essentially, check for the command line
	// then just call ShellExecute()!

  if (aURL)
  {
    // extract the url spec from the url
    nsXPIDLCString urlSpec;
    aURL->GetSpec(getter_Copies(urlSpec));

		LONG r = (LONG) ::ShellExecute( NULL, "open", (const char *) urlSpec, NULL, NULL, SW_SHOWNORMAL);
		if (r < 32) 
			rv = NS_ERROR_FAILURE;
  }

  return rv;
}

nsresult nsOSHelperAppService::GetFileTokenForPath(const PRUnichar * platformAppPath, nsIFile ** aFile)
{
  nsCOMPtr<nsILocalFile> localFile (do_CreateInstance(NS_LOCAL_FILE_CONTRACTID));
  nsresult rv = NS_OK;

  if (localFile)
  {
    if (localFile)
      localFile->InitWithUnicodePath(platformAppPath);
    *aFile = localFile;
    NS_IF_ADDREF(*aFile);
  }
  else
    rv = NS_ERROR_FAILURE;

  return rv;
}

/////////////////////////////////////////////////////////////////////////////////////////////////
// nsIMIMEService method over-rides used to gather information from the windows registry for
// various mime types. 
////////////////////////////////////////////////////////////////////////////////////////////////
NS_IMETHODIMP nsOSHelperAppService::GetFromExtension(const char *aFileExt, nsIMIMEInfo **_retval) 
{
  // first, see if the base class already has an entry....
  nsresult rv = nsExternalHelperAppService::GetFromExtension(aFileExt, _retval);
  if (NS_SUCCEEDED(rv) && *_retval) return NS_OK; // okay we got an entry so we are done.
  if (!aFileExt || *aFileExt == '\0') return NS_ERROR_FAILURE;

  rv = NS_OK;

  // windows registry assumes your file extension is going to include the '.'.
  // so make sure it's there...
  nsCAutoString fileExtToUse;
  if (aFileExt && aFileExt[0] != '.')
    fileExtToUse = '.';

  fileExtToUse.Append(aFileExt);

  // o.t. try to get an entry from the windows registry.
   HKEY hKey;
   LONG err = ::RegOpenKeyEx( HKEY_CLASSES_ROOT, fileExtToUse, 0, KEY_QUERY_VALUE, &hKey);
   if (err == ERROR_SUCCESS)
   {
      LPBYTE pBytes = GetValueBytes( hKey, "Content Type");
      LPBYTE pFileDescription = GetValueBytes(hKey, "");

      nsCOMPtr<nsIMIMEInfo> mimeInfo (do_CreateInstance(NS_MIMEINFO_CONTRACTID));
      if (mimeInfo && pBytes)
      {
        mimeInfo->SetMIMEType((char *) pBytes);
        // if the file extension includes the '.' then we don't want to include that when we append
        // it to the mime info object.
        if (aFileExt && *aFileExt == '.' && (aFileExt+1))
          mimeInfo->AppendExtension(aFileExt+1);
        else
          mimeInfo->AppendExtension(aFileExt);

        mimeInfo->SetPreferredAction(nsIMIMEInfo::useSystemDefault);

        nsAutoString description;
        description.AssignWithConversion((char *) pFileDescription);

        PRInt32 pos = description.FindChar('.', PR_TRUE);
        if (pos > 0) 
          description.Truncate(pos); 
        // the format of the description usually looks like appname.version.something.
        // for now, let's try to make it pretty and just show you the appname.

        mimeInfo->SetApplicationDescription(description.GetUnicode());

        // if we got here, then set our return variable and be sure to add this new mime Info object to the hash
        // table so we don't hit the registry the next time we look up this content type.
        *_retval = mimeInfo;
        NS_ADDREF(*_retval);
        AddMimeInfoToCache(mimeInfo);
      }
      else
        rv = NS_ERROR_FAILURE; // we failed to really find an entry in the registry

      delete [] pBytes;
      delete [] pFileDescription;

      // close the key
     ::RegCloseKey(hKey);
   }

   // we failed to find a mime type.
   if (!*_retval) rv = NS_ERROR_FAILURE;
    
   return rv;
}

NS_IMETHODIMP nsOSHelperAppService::GetFromMIMEType(const char *aMIMEType, nsIMIMEInfo ** _retval) 
{
  // first, see if the base class already has an entry....
  nsresult rv = nsExternalHelperAppService::GetFromMIMEType(aMIMEType, _retval);
  if (NS_SUCCEEDED(rv) && *_retval) return NS_OK; // okay we got an entry so we are done.

  // (1) try to use the windows mime database to see if there is a mapping to a file extension
  // (2) try to see if we have some left over 4.x registry info we can peek at...
  nsCAutoString fileExtension;
  GetExtensionFromWindowsMimeDatabase(aMIMEType, fileExtension);
  if (fileExtension.IsEmpty())
    GetExtensionFrom4xRegistryInfo(aMIMEType, fileExtension);

  // now look up based on the file extension.
  if (!fileExtension.IsEmpty())
    return GetFromExtension(fileExtension, _retval);
  else
   rv = NS_ERROR_FAILURE;

  return rv;
}