/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsString.h"
#include "nsIComponentManager.h"
#include "nsCOMPtr.h"
#include "nsXPCOM.h"
#include "nsISupportsPrimitives.h"
#include "nsXPIDLString.h"
#include "nsScriptLoader.h"
#include "nsEscape.h"
#include "nsIParser.h"
#include "nsIDTD.h"
#include "nsNetCID.h"
#include "nsNetUtil.h"
#include "nsParserCIID.h"
#include "nsContentUtils.h"
#include "nsIContentSink.h"
#include "nsIDocumentEncoder.h"
#include "nsIDOMDocumentFragment.h"
#include "nsIFragmentContentSink.h"
#include "nsIDOMDocument.h"
#include "nsIDOMNodeList.h"
#include "nsIDOMNode.h"
#include "nsIDOMElement.h"
#include "nsIDocument.h"
#include "nsIContent.h"
#include "nsAttrName.h"
#include "nsHTMLParts.h"
#include "nsContentCID.h"
#include "nsIScriptableUnescapeHTML.h"
#include "nsParserUtils.h"
#include "nsAutoPtr.h"
#include "nsTreeSanitizer.h"
#include "nsHtml5Module.h"
#include "mozilla/dom/DocumentFragment.h"

#define XHTML_DIV_TAG "div xmlns=\"http://www.w3.org/1999/xhtml\""

using namespace mozilla::dom;

NS_IMPL_ISUPPORTS(nsParserUtils,
                  nsIScriptableUnescapeHTML,
                  nsIParserUtils)

NS_IMETHODIMP
nsParserUtils::ConvertToPlainText(const nsAString& aFromStr,
                                  uint32_t aFlags,
                                  uint32_t aWrapCol,
                                  nsAString& aToStr)
{
  return nsContentUtils::ConvertToPlainText(aFromStr,
    aToStr,
    aFlags,
    aWrapCol);
}

NS_IMETHODIMP
nsParserUtils::Unescape(const nsAString& aFromStr,
                        nsAString& aToStr)
{
  return nsContentUtils::ConvertToPlainText(aFromStr,
    aToStr,
    nsIDocumentEncoder::OutputSelectionOnly |
    nsIDocumentEncoder::OutputAbsoluteLinks,
    0);
}

NS_IMETHODIMP
nsParserUtils::Sanitize(const nsAString& aFromStr,
                        uint32_t aFlags,
                        nsAString& aToStr)
{
  nsCOMPtr<nsIURI> uri;
  NS_NewURI(getter_AddRefs(uri), "about:blank");
  nsCOMPtr<nsIPrincipal> principal =
    do_CreateInstance("@mozilla.org/nullprincipal;1");
  nsCOMPtr<nsIDOMDocument> domDocument;
  nsresult rv = NS_NewDOMDocument(getter_AddRefs(domDocument),
                                  EmptyString(),
                                  EmptyString(),
                                  nullptr,
                                  uri,
                                  uri,
                                  principal,
                                  true,
                                  nullptr,
                                  DocumentFlavorHTML);
  NS_ENSURE_SUCCESS(rv, rv);

  nsCOMPtr<nsIDocument> document = do_QueryInterface(domDocument);
  rv = nsContentUtils::ParseDocumentHTML(aFromStr, document, false);
  NS_ENSURE_SUCCESS(rv, rv);

  nsTreeSanitizer sanitizer(aFlags);
  sanitizer.Sanitize(document);

  nsCOMPtr<nsIDocumentEncoder> encoder =
    do_CreateInstance(NS_DOC_ENCODER_CONTRACTID_BASE "text/html");

  encoder->NativeInit(document,
                      NS_LITERAL_STRING("text/html"),
                      nsIDocumentEncoder::OutputDontRewriteEncodingDeclaration |
                      nsIDocumentEncoder::OutputNoScriptContent |
                      nsIDocumentEncoder::OutputEncodeBasicEntities |
                      nsIDocumentEncoder::OutputLFLineBreak |
                      nsIDocumentEncoder::OutputRaw);

  return encoder->EncodeToString(aToStr);
}

NS_IMETHODIMP
nsParserUtils::ParseFragment(const nsAString& aFragment,
                             bool aIsXML,
                             nsIURI* aBaseURI,
                             nsIDOMElement* aContextElement,
                             nsIDOMDocumentFragment** aReturn)
{
  return nsParserUtils::ParseFragment(aFragment,
                                      0,
                                      aIsXML,
                                      aBaseURI,
                                      aContextElement,
                                      aReturn);
}

NS_IMETHODIMP
nsParserUtils::ParseFragment(const nsAString& aFragment,
                             uint32_t aFlags,
                             bool aIsXML,
                             nsIURI* aBaseURI,
                             nsIDOMElement* aContextElement,
                             nsIDOMDocumentFragment** aReturn)
{
  NS_ENSURE_ARG(aContextElement);
  *aReturn = nullptr;

  nsCOMPtr<nsIDocument> document;
  nsCOMPtr<nsIDOMDocument> domDocument;
  nsCOMPtr<nsIDOMNode> contextNode;
  contextNode = do_QueryInterface(aContextElement);
  contextNode->GetOwnerDocument(getter_AddRefs(domDocument));
  document = do_QueryInterface(domDocument);
  NS_ENSURE_TRUE(document, NS_ERROR_NOT_AVAILABLE);

  nsAutoScriptBlockerSuppressNodeRemoved autoBlocker;

  // stop scripts
  nsRefPtr<nsScriptLoader> loader;
  bool scripts_enabled = false;
  if (document) {
    loader = document->ScriptLoader();
    scripts_enabled = loader->GetEnabled();
  }
  if (scripts_enabled) {
    loader->SetEnabled(false);
  }

  // Wrap things in a div or body for parsing, but it won't show up in
  // the fragment.
  nsAutoTArray<nsString, 2> tagStack;
  nsAutoCString base, spec;
  if (aIsXML) {
    // XHTML
    if (aBaseURI) {
      base.AppendLiteral(XHTML_DIV_TAG);
      base.AppendLiteral(" xml:base=\"");
      aBaseURI->GetSpec(spec);
      // nsEscapeHTML is good enough, because we only need to get
      // quotes, ampersands, and angle brackets
      char* escapedSpec = nsEscapeHTML(spec.get());
      if (escapedSpec)
        base += escapedSpec;
      NS_Free(escapedSpec);
      base.Append('"');
      tagStack.AppendElement(NS_ConvertUTF8toUTF16(base));
    }  else {
      tagStack.AppendElement(NS_LITERAL_STRING(XHTML_DIV_TAG));
    }
  }

  nsresult rv = NS_OK;
  nsCOMPtr<nsIContent> fragment;
  if (aIsXML) {
    rv = nsContentUtils::ParseFragmentXML(aFragment,
                                          document,
                                          tagStack,
                                          true,
                                          aReturn);
    fragment = do_QueryInterface(*aReturn);
  } else {
    NS_ADDREF(*aReturn = new DocumentFragment(document->NodeInfoManager()));
    fragment = do_QueryInterface(*aReturn);
    rv = nsContentUtils::ParseFragmentHTML(aFragment,
                                           fragment,
                                           nsGkAtoms::body,
                                           kNameSpaceID_XHTML,
                                           false,
                                           true);
    // Now, set the base URI on all subtree roots.
    if (aBaseURI) {
      aBaseURI->GetSpec(spec);
      nsAutoString spec16;
      CopyUTF8toUTF16(spec, spec16);
      nsIContent* node = fragment->GetFirstChild();
      while (node) {
        if (node->IsElement()) {
          node->SetAttr(kNameSpaceID_XML,
                        nsGkAtoms::base,
                        nsGkAtoms::xml,
                        spec16,
                        false);
        }
        node = node->GetNextSibling();
      }
    }
  }
  if (fragment) {
    nsTreeSanitizer sanitizer(aFlags);
    sanitizer.Sanitize(fragment);
  }

  if (scripts_enabled) {
    loader->SetEnabled(true);
  }

  return rv;
}