widget/src/xpwidgets/nsHTMLFormatConverter.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
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  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
  13  * License.
  14  *
  15  * The Original Code is mozilla.org code.
  16  *
  17  * The Initial Developer of the Original Code is
  18  * Netscape Communications Corporation.
  19  * Portions created by the Initial Developer are Copyright (C) 1998
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *   Pierre Phaneuf <pp@ludusdesign.com>
  24  *
  25  * Alternatively, the contents of this file may be used under the terms of
  26  * either the GNU General Public License Version 2 or later (the "GPL"), or
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  37  * ***** END LICENSE BLOCK ***** */
  38
  39 #include "nsHTMLFormatConverter.h"
  40
  41 #include "nsCRT.h"
  42 #include "nsISupportsArray.h"
  43 #include "nsIComponentManager.h"
  44 #include "nsCOMPtr.h"
  45 #include "nsXPCOM.h"
  46 #include "nsISupportsPrimitives.h"
  47
  48 #include "nsITransferable.h" // for mime defs, this is BAD
  49
  50 // HTML convertor stuff
  51 #include "nsIParser.h"
  52 #include "nsIDTD.h"
  53 #include "nsParserCIID.h"
  54 #include "nsIContentSink.h"
  55 #include "nsPrimitiveHelpers.h"
  56 #include "nsIDocumentEncoder.h"
  57 #include "nsIHTMLToTextSink.h"
  58
  59 static NS_DEFINE_CID(kCParserCID, NS_PARSER_CID);
  60
  61 nsHTMLFormatConverter::nsHTMLFormatConverter()
  62 {
  63 }
  64
  65 nsHTMLFormatConverter::~nsHTMLFormatConverter()
  66 {
  67 }
  68
  69 NS_IMPL_ISUPPORTS1(nsHTMLFormatConverter, nsIFormatConverter)
  70
  71 //
  72 // GetInputDataFlavors
  73 //
  74 // Creates a new list and returns the list of all the flavors this converter
  75 // knows how to import. In this case, it's just HTML.
  76 //
  77 // Flavors (strings) are wrapped in a primitive object so that JavaScript can
  78 // access them easily via XPConnect.
  79 //
  80 NS_IMETHODIMP
  81 nsHTMLFormatConverter::GetInputDataFlavors(nsISupportsArray **_retval)
  82 {
  83   if ( !_retval )
  84     return NS_ERROR_INVALID_ARG;
  85
  86   nsresult rv = NS_NewISupportsArray ( _retval );  // addrefs for us
  87   if ( NS_SUCCEEDED(rv) )
  88     rv = AddFlavorToList ( *_retval, kHTMLMime );
  89
  90   return rv;
  91
  92 } // GetInputDataFlavors
  93
  94
  95 //
  96 // GetOutputDataFlavors
  97 //
  98 // Creates a new list and returns the list of all the flavors this converter
  99 // knows how to export (convert). In this case, it's all sorts of things that HTML can be
 100 // converted to.
 101 //
 102 // Flavors (strings) are wrapped in a primitive object so that JavaScript can
 103 // access them easily via XPConnect.
 104 //
 105 NS_IMETHODIMP
 106 nsHTMLFormatConverter::GetOutputDataFlavors(nsISupportsArray **_retval)
 107 {
 108   if ( !_retval )
 109     return NS_ERROR_INVALID_ARG;
 110
 111   nsresult rv = NS_NewISupportsArray ( _retval );  // addrefs for us
 112   if ( NS_SUCCEEDED(rv) ) {
 113     rv = AddFlavorToList ( *_retval, kHTMLMime );
 114     if ( NS_FAILED(rv) )
 115       return rv;
 116 #if NOT_NOW
 117 // pinkerton
 118 // no one uses this flavor right now, so it's just slowing things down. If anyone cares I
 119 // can put it back in.
 120     rv = AddFlavorToList ( *_retval, kAOLMailMime );
 121     if ( NS_FAILED(rv) )
 122       return rv;
 123 #endif
 124     rv = AddFlavorToList ( *_retval, kUnicodeMime );
 125     if ( NS_FAILED(rv) )
 126       return rv;
 127   }
 128   return rv;
 129
 130 } // GetOutputDataFlavors
 131
 132
 133 //
 134 // AddFlavorToList
 135 //
 136 // Convenience routine for adding a flavor wrapped in an nsISupportsCString object
 137 // to a list
 138 //
 139 nsresult
 140 nsHTMLFormatConverter :: AddFlavorToList ( nsISupportsArray* inList, const char* inFlavor )
 141 {
 142   nsresult rv;
 143
 144   nsCOMPtr<nsISupportsCString> dataFlavor =
 145       do_CreateInstance(NS_SUPPORTS_CSTRING_CONTRACTID, &rv);
 146   if ( dataFlavor ) {
 147     dataFlavor->SetData ( nsDependentCString(inFlavor) );
 148     // add to list as an nsISupports so the correct interface gets the addref
 149     // in AppendElement()
 150     nsCOMPtr<nsISupports> genericFlavor ( do_QueryInterface(dataFlavor) );
 151     inList->AppendElement ( genericFlavor);
 152   }
 153   return rv;
 154
 155 } // AddFlavorToList
 156
 157
 158 //
 159 // CanConvert
 160 //
 161 // Determines if we support the given conversion. Currently, this method only
 162 // converts from HTML to others.
 163 //
 164 NS_IMETHODIMP
 165 nsHTMLFormatConverter::CanConvert(const char *aFromDataFlavor, const char *aToDataFlavor, PRBool *_retval)
 166 {
 167   if ( !_retval )
 168     return NS_ERROR_INVALID_ARG;
 169
 170     // STRING USE WARNING: reduce conversions here?
 171
 172   *_retval = PR_FALSE;
 173   nsAutoString fromFlavor; fromFlavor.AssignWithConversion( aFromDataFlavor );
 174   if ( !nsCRT::strcmp(aFromDataFlavor, kHTMLMime) ) {
 175     if ( !nsCRT::strcmp(aToDataFlavor, kHTMLMime) )
 176       *_retval = PR_TRUE;
 177     else if ( !nsCRT::strcmp(aToDataFlavor, kUnicodeMime) )
 178       *_retval = PR_TRUE;
 179 #if NOT_NOW
 180 // pinkerton
 181 // no one uses this flavor right now, so it's just slowing things down. If anyone cares I
 182 // can put it back in.
 183     else if ( toFlavor.Equals(kAOLMailMime) )
 184       *_retval = PR_TRUE;
 185 #endif
 186   }
 187   return NS_OK;
 188
 189 } // CanConvert
 190
 191
 192
 193 //
 194 // Convert
 195 //
 196 // Convert data from one flavor to another. The data is wrapped in primitive objects so that it is
 197 // accessible from JS. Currently, this only accepts HTML input, so anything else is invalid.
 198 //
 199 //XXX This method copies the data WAAAAY too many time for my liking. Grrrrrr. Mostly it's because
 200 //XXX we _must_ put things into nsStrings so that the parser will accept it. Lame lame lame lame. We
 201 //XXX also can't just get raw unicode out of the nsString, so we have to allocate heap to get
 202 //XXX unicode out of the string. Lame lame lame.
 203 //
 204 NS_IMETHODIMP
 205 nsHTMLFormatConverter::Convert(const char *aFromDataFlavor, nsISupports *aFromData, PRUint32 aDataLen,
 206                                const char *aToDataFlavor, nsISupports **aToData, PRUint32 *aDataToLen)
 207 {
 208   if ( !aToData || !aDataToLen )
 209     return NS_ERROR_INVALID_ARG;
 210
 211   nsresult rv = NS_OK;
 212
 213   if ( !nsCRT::strcmp(aFromDataFlavor, kHTMLMime) ) {
 214     nsCAutoString toFlavor ( aToDataFlavor );
 215
 216     // HTML on clipboard is going to always be double byte so it will be in a primitive
 217     // class of nsISupportsString. Also, since the data is in two byte chunks the
 218     // length represents the length in 1-byte chars, so we need to divide by two.
 219     nsCOMPtr<nsISupportsString> dataWrapper0 ( do_QueryInterface(aFromData) );
 220     if (!dataWrapper0) {
 221       return NS_ERROR_INVALID_ARG;
 222     }
 223
 224     nsAutoString dataStr;
 225     dataWrapper0->GetData ( dataStr );  //¥¥¥ COPY #1
 226     // note: conversion to text/plain is done inside the clipboard. we do not need to worry
 227     // about it here.
 228     if ( toFlavor.Equals(kHTMLMime) || toFlavor.Equals(kUnicodeMime) ) {
 229       nsresult res;
 230       if (toFlavor.Equals(kHTMLMime)) {
 231         PRInt32 dataLen = dataStr.Length() * 2;
 232         nsPrimitiveHelpers::CreatePrimitiveForData ( toFlavor.get(), (void*)dataStr.get(), dataLen, aToData );
 233         if ( *aToData )
 234           *aDataToLen = dataLen;
 235       } else {
 236         nsAutoString outStr;
 237         res = ConvertFromHTMLToUnicode(dataStr, outStr);
 238         if (NS_SUCCEEDED(res)) {
 239           PRInt32 dataLen = outStr.Length() * 2;
 240           nsPrimitiveHelpers::CreatePrimitiveForData ( toFlavor.get(), (void*)outStr.get(), dataLen, aToData );
 241           if ( *aToData )
 242             *aDataToLen = dataLen;
 243         }
 244       }
 245     } // else if HTML or Unicode
 246     else if ( toFlavor.Equals(kAOLMailMime) ) {
 247       nsAutoString outStr;
 248       if ( NS_SUCCEEDED(ConvertFromHTMLToAOLMail(dataStr, outStr)) ) {
 249         PRInt32 dataLen = outStr.Length() * 2;
 250         nsPrimitiveHelpers::CreatePrimitiveForData ( toFlavor.get(), (void*)outStr.get(), dataLen, aToData );
 251         if ( *aToData )
 252           *aDataToLen = dataLen;
 253       }
 254     } // else if AOL mail
 255     else {
 256       *aToData = nsnull;
 257       *aDataToLen = 0;
 258       rv = NS_ERROR_FAILURE;
 259     }
 260   } // if we got html mime
 261   else
 262     rv = NS_ERROR_FAILURE;
 263
 264   return rv;
 265
 266 } // Convert
 267
 268
 269 //
 270 // ConvertFromHTMLToUnicode
 271 //
 272 // Takes HTML and converts it to plain text but in unicode.
 273 //
 274 NS_IMETHODIMP
 275 nsHTMLFormatConverter::ConvertFromHTMLToUnicode(const nsAutoString & aFromStr, nsAutoString & aToStr)
 276 {
 277   // create the parser to do the conversion.
 278   aToStr.SetLength(0);
 279   nsresult rv;
 280   nsCOMPtr<nsIParser> parser = do_CreateInstance(kCParserCID, &rv);
 281   if ( !parser )
 282     return rv;
 283
 284   // convert it!
 285   nsCOMPtr<nsIContentSink> sink;
 286
 287   sink = do_CreateInstance(NS_PLAINTEXTSINK_CONTRACTID);
 288   NS_ENSURE_TRUE(sink, NS_ERROR_FAILURE);
 289
 290   nsCOMPtr<nsIHTMLToTextSink> textSink(do_QueryInterface(sink));
 291   NS_ENSURE_TRUE(textSink, NS_ERROR_FAILURE);
 292
 293   textSink->Initialize(&aToStr, nsIDocumentEncoder::OutputSelectionOnly
 294                        | nsIDocumentEncoder::OutputAbsoluteLinks, 0);
 295
 296   parser->SetContentSink(sink);
 297
 298   parser->Parse(aFromStr, 0, NS_LITERAL_CSTRING("text/html"), PR_TRUE, eDTDMode_fragment);
 299
 300   return NS_OK;
 301 } // ConvertFromHTMLToUnicode
 302
 303
 304 NS_IMETHODIMP
 305 nsHTMLFormatConverter::ConvertFromHTMLToAOLMail(const nsAutoString & aFromStr,
 306                                                 nsAutoString & aToStr)
 307 {
 308   aToStr.AssignLiteral("<HTML>");
 309   aToStr.Append(aFromStr);
 310   aToStr.AppendLiteral("</HTML>");
 311
 312   return NS_OK;
 313 }
 314