widget/nsHTMLFormatConverter.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "nsHTMLFormatConverter.h"
   7
   8 #include "nsCRT.h"
   9 #include "nsISupportsArray.h"
  10 #include "nsIComponentManager.h"
  11 #include "nsCOMPtr.h"
  12 #include "nsXPCOM.h"
  13 #include "nsISupportsPrimitives.h"
  14
  15 #include "nsITransferable.h" // for mime defs, this is BAD
  16
  17 // HTML convertor stuff
  18 #include "nsPrimitiveHelpers.h"
  19 #include "nsIDocumentEncoder.h"
  20 #include "nsContentUtils.h"
  21
  22 nsHTMLFormatConverter::nsHTMLFormatConverter()
  23 {
  24 }
  25
  26 nsHTMLFormatConverter::~nsHTMLFormatConverter()
  27 {
  28 }
  29
  30 NS_IMPL_ISUPPORTS(nsHTMLFormatConverter, nsIFormatConverter)
  31
  32 //
  33 // GetInputDataFlavors
  34 //
  35 // Creates a new list and returns the list of all the flavors this converter
  36 // knows how to import. In this case, it's just HTML.
  37 //
  38 // Flavors (strings) are wrapped in a primitive object so that JavaScript can
  39 // access them easily via XPConnect.
  40 //
  41 NS_IMETHODIMP
  42 nsHTMLFormatConverter::GetInputDataFlavors(nsISupportsArray **_retval)
  43 {
  44   if ( !_retval )
  45     return NS_ERROR_INVALID_ARG;
  46
  47   nsresult rv = NS_NewISupportsArray ( _retval );  // addrefs for us
  48   if ( NS_SUCCEEDED(rv) )
  49     rv = AddFlavorToList ( *_retval, kHTMLMime );
  50
  51   return rv;
  52
  53 } // GetInputDataFlavors
  54
  55
  56 //
  57 // GetOutputDataFlavors
  58 //
  59 // Creates a new list and returns the list of all the flavors this converter
  60 // knows how to export (convert). In this case, it's all sorts of things that HTML can be
  61 // converted to.
  62 //
  63 // Flavors (strings) are wrapped in a primitive object so that JavaScript can
  64 // access them easily via XPConnect.
  65 //
  66 NS_IMETHODIMP
  67 nsHTMLFormatConverter::GetOutputDataFlavors(nsISupportsArray **_retval)
  68 {
  69   if ( !_retval )
  70     return NS_ERROR_INVALID_ARG;
  71
  72   nsresult rv = NS_NewISupportsArray ( _retval );  // addrefs for us
  73   if ( NS_SUCCEEDED(rv) ) {
  74     rv = AddFlavorToList ( *_retval, kHTMLMime );
  75     if ( NS_FAILED(rv) )
  76       return rv;
  77 #if NOT_NOW
  78 // pinkerton
  79 // no one uses this flavor right now, so it's just slowing things down. If anyone cares I
  80 // can put it back in.
  81     rv = AddFlavorToList ( *_retval, kAOLMailMime );
  82     if ( NS_FAILED(rv) )
  83       return rv;
  84 #endif
  85     rv = AddFlavorToList ( *_retval, kUnicodeMime );
  86     if ( NS_FAILED(rv) )
  87       return rv;
  88   }
  89   return rv;
  90
  91 } // GetOutputDataFlavors
  92
  93
  94 //
  95 // AddFlavorToList
  96 //
  97 // Convenience routine for adding a flavor wrapped in an nsISupportsCString object
  98 // to a list
  99 //
 100 nsresult
 101 nsHTMLFormatConverter :: AddFlavorToList ( nsISupportsArray* inList, const char* inFlavor )
 102 {
 103   nsresult rv;
 104
 105   nsCOMPtr<nsISupportsCString> dataFlavor =
 106       do_CreateInstance(NS_SUPPORTS_CSTRING_CONTRACTID, &rv);
 107   if ( dataFlavor ) {
 108     dataFlavor->SetData ( nsDependentCString(inFlavor) );
 109     // add to list as an nsISupports so the correct interface gets the addref
 110     // in AppendElement()
 111     nsCOMPtr<nsISupports> genericFlavor ( do_QueryInterface(dataFlavor) );
 112     inList->AppendElement ( genericFlavor);
 113   }
 114   return rv;
 115
 116 } // AddFlavorToList
 117
 118
 119 //
 120 // CanConvert
 121 //
 122 // Determines if we support the given conversion. Currently, this method only
 123 // converts from HTML to others.
 124 //
 125 NS_IMETHODIMP
 126 nsHTMLFormatConverter::CanConvert(const char *aFromDataFlavor, const char *aToDataFlavor, bool *_retval)
 127 {
 128   if ( !_retval )
 129     return NS_ERROR_INVALID_ARG;
 130
 131   *_retval = false;
 132   if ( !nsCRT::strcmp(aFromDataFlavor, kHTMLMime) ) {
 133     if ( !nsCRT::strcmp(aToDataFlavor, kHTMLMime) )
 134       *_retval = true;
 135     else if ( !nsCRT::strcmp(aToDataFlavor, kUnicodeMime) )
 136       *_retval = true;
 137 #if NOT_NOW
 138 // pinkerton
 139 // no one uses this flavor right now, so it's just slowing things down. If anyone cares I
 140 // can put it back in.
 141     else if ( toFlavor.Equals(kAOLMailMime) )
 142       *_retval = true;
 143 #endif
 144   }
 145   return NS_OK;
 146
 147 } // CanConvert
 148
 149
 150
 151 //
 152 // Convert
 153 //
 154 // Convert data from one flavor to another. The data is wrapped in primitive objects so that it is
 155 // accessible from JS. Currently, this only accepts HTML input, so anything else is invalid.
 156 //
 157 //XXX This method copies the data WAAAAY too many time for my liking. Grrrrrr. Mostly it's because
 158 //XXX we _must_ put things into nsStrings so that the parser will accept it. Lame lame lame lame. We
 159 //XXX also can't just get raw unicode out of the nsString, so we have to allocate heap to get
 160 //XXX unicode out of the string. Lame lame lame.
 161 //
 162 NS_IMETHODIMP
 163 nsHTMLFormatConverter::Convert(const char *aFromDataFlavor, nsISupports *aFromData, uint32_t aDataLen,
 164                                const char *aToDataFlavor, nsISupports **aToData, uint32_t *aDataToLen)
 165 {
 166   if ( !aToData || !aDataToLen )
 167     return NS_ERROR_INVALID_ARG;
 168
 169   nsresult rv = NS_OK;
 170   *aToData = nullptr;
 171   *aDataToLen = 0;
 172
 173   if ( !nsCRT::strcmp(aFromDataFlavor, kHTMLMime) ) {
 174     nsAutoCString toFlavor ( aToDataFlavor );
 175
 176     // HTML on clipboard is going to always be double byte so it will be in a primitive
 177     // class of nsISupportsString. Also, since the data is in two byte chunks the
 178     // length represents the length in 1-byte chars, so we need to divide by two.
 179     nsCOMPtr<nsISupportsString> dataWrapper0 ( do_QueryInterface(aFromData) );
 180     if (!dataWrapper0) {
 181       return NS_ERROR_INVALID_ARG;
 182     }
 183
 184     nsAutoString dataStr;
 185     dataWrapper0->GetData ( dataStr );  //¥¥¥ COPY #1
 186     // note: conversion to text/plain is done inside the clipboard. we do not need to worry
 187     // about it here.
 188     if ( toFlavor.Equals(kHTMLMime) || toFlavor.Equals(kUnicodeMime) ) {
 189       nsresult res;
 190       if (toFlavor.Equals(kHTMLMime)) {
 191         int32_t dataLen = dataStr.Length() * 2;
 192         nsPrimitiveHelpers::CreatePrimitiveForData ( toFlavor.get(), dataStr.get(), dataLen, aToData );
 193         if ( *aToData )
 194           *aDataToLen = dataLen;
 195       } else {
 196         nsAutoString outStr;
 197         res = ConvertFromHTMLToUnicode(dataStr, outStr);
 198         if (NS_SUCCEEDED(res)) {
 199           int32_t dataLen = outStr.Length() * 2;
 200           nsPrimitiveHelpers::CreatePrimitiveForData ( toFlavor.get(), outStr.get(), dataLen, aToData );
 201           if ( *aToData )
 202             *aDataToLen = dataLen;
 203         }
 204       }
 205     } // else if HTML or Unicode
 206     else if ( toFlavor.Equals(kAOLMailMime) ) {
 207       nsAutoString outStr;
 208       if ( NS_SUCCEEDED(ConvertFromHTMLToAOLMail(dataStr, outStr)) ) {
 209         int32_t dataLen = outStr.Length() * 2;
 210         nsPrimitiveHelpers::CreatePrimitiveForData ( toFlavor.get(), outStr.get(), dataLen, aToData );
 211         if ( *aToData )
 212           *aDataToLen = dataLen;
 213       }
 214     } // else if AOL mail
 215     else {
 216       rv = NS_ERROR_FAILURE;
 217     }
 218   } // if we got html mime
 219   else
 220     rv = NS_ERROR_FAILURE;
 221
 222   return rv;
 223
 224 } // Convert
 225
 226
 227 //
 228 // ConvertFromHTMLToUnicode
 229 //
 230 // Takes HTML and converts it to plain text but in unicode.
 231 //
 232 NS_IMETHODIMP
 233 nsHTMLFormatConverter::ConvertFromHTMLToUnicode(const nsAutoString & aFromStr, nsAutoString & aToStr)
 234 {
 235   return nsContentUtils::ConvertToPlainText(aFromStr,
 236     aToStr,
 237     nsIDocumentEncoder::OutputSelectionOnly |
 238     nsIDocumentEncoder::OutputAbsoluteLinks |
 239     nsIDocumentEncoder::OutputNoScriptContent |
 240     nsIDocumentEncoder::OutputNoFramesContent,
 241     0);
 242 } // ConvertFromHTMLToUnicode
 243
 244
 245 NS_IMETHODIMP
 246 nsHTMLFormatConverter::ConvertFromHTMLToAOLMail(const nsAutoString & aFromStr,
 247                                                 nsAutoString & aToStr)
 248 {
 249   aToStr.AssignLiteral("<HTML>");
 250   aToStr.Append(aFromStr);
 251   aToStr.AppendLiteral("</HTML>");
 252
 253   return NS_OK;
 254 }
 255