/* -*- Mode: C++; tab-width: 4; 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 "txUnknownHandler.h"

#include <utility>

#include "mozilla/UniquePtrExtensions.h"
#include "nsGkAtoms.h"
#include "txExecutionState.h"
#include "txStringUtils.h"
#include "txStylesheet.h"

using mozilla::UniquePtr;
using mozilla::WrapUnique;

txUnknownHandler::txUnknownHandler(txExecutionState* aEs)
    : mEs(aEs), mFlushed(false) {
  MOZ_COUNT_CTOR_INHERITED(txUnknownHandler, txBufferingHandler);
}

txUnknownHandler::~txUnknownHandler() {
  MOZ_COUNT_DTOR_INHERITED(txUnknownHandler, txBufferingHandler);
}

nsresult txUnknownHandler::attribute(nsAtom* aPrefix, nsAtom* aLocalName,
                                     nsAtom* aLowercaseLocalName, int32_t aNsID,
                                     const nsString& aValue) {
  return mFlushed
             ? mEs->mResultHandler->attribute(
                   aPrefix, aLocalName, aLowercaseLocalName, aNsID, aValue)
             : txBufferingHandler::attribute(
                   aPrefix, aLocalName, aLowercaseLocalName, aNsID, aValue);
}

nsresult txUnknownHandler::attribute(nsAtom* aPrefix,
                                     const nsAString& aLocalName,
                                     const int32_t aNsID,
                                     const nsString& aValue) {
  return mFlushed ? mEs->mResultHandler->attribute(aPrefix, aLocalName, aNsID,
                                                   aValue)
                  : txBufferingHandler::attribute(aPrefix, aLocalName, aNsID,
                                                  aValue);
}

nsresult txUnknownHandler::characters(const nsAString& aData, bool aDOE) {
  return mFlushed ? mEs->mResultHandler->characters(aData, aDOE)
                  : txBufferingHandler::characters(aData, aDOE);
}

nsresult txUnknownHandler::comment(const nsString& aData) {
  return mFlushed ? mEs->mResultHandler->comment(aData)
                  : txBufferingHandler::comment(aData);
}

nsresult txUnknownHandler::endDocument(nsresult aResult) {
  if (!mFlushed) {
    if (NS_FAILED(aResult)) {
      return NS_OK;
    }

    // This is an unusual case, no output method has been set and we
    // didn't create a document element. Switching to XML output mode
    // anyway.

    // Make sure that mEs->mResultHandler == this is true, otherwise we'll
    // leak mEs->mResultHandler in createHandlerAndFlush.
    NS_ASSERTION(mEs->mResultHandler == this,
                 "We're leaking mEs->mResultHandler.");

    nsresult rv = createHandlerAndFlush(false, u""_ns, kNameSpaceID_None);
    NS_ENSURE_SUCCESS(rv, rv);
  }

  return mEs->mResultHandler->endDocument(aResult);
}

nsresult txUnknownHandler::endElement() {
  return mFlushed ? mEs->mResultHandler->endElement()
                  : txBufferingHandler::endElement();
}

nsresult txUnknownHandler::processingInstruction(const nsString& aTarget,
                                                 const nsString& aData) {
  return mFlushed ? mEs->mResultHandler->processingInstruction(aTarget, aData)
                  : txBufferingHandler::processingInstruction(aTarget, aData);
}

nsresult txUnknownHandler::startDocument() {
  return mFlushed ? mEs->mResultHandler->startDocument()
                  : txBufferingHandler::startDocument();
}

nsresult txUnknownHandler::startElement(nsAtom* aPrefix, nsAtom* aLocalName,
                                        nsAtom* aLowercaseLocalName,
                                        int32_t aNsID) {
  if (!mFlushed) {
    // Make sure that mEs->mResultHandler == this is true, otherwise we'll
    // leak mEs->mResultHandler in createHandlerAndFlush.
    NS_ASSERTION(mEs->mResultHandler == this,
                 "We're leaking mEs->mResultHandler.");

    RefPtr<nsAtom> owner;
    if (!aLowercaseLocalName) {
      owner = TX_ToLowerCaseAtom(aLocalName);
      NS_ENSURE_TRUE(owner, NS_ERROR_OUT_OF_MEMORY);

      aLowercaseLocalName = owner;
    }

    bool htmlRoot = aNsID == kNameSpaceID_None && !aPrefix &&
                    aLowercaseLocalName == nsGkAtoms::html;

    // Use aLocalName and not aLowercaseLocalName in case the output
    // handler cares about case. For eHTMLOutput the handler will hardcode
    // to 'html' anyway.
    nsresult rv = createHandlerAndFlush(
        htmlRoot, nsDependentAtomString(aLocalName), aNsID);
    NS_ENSURE_SUCCESS(rv, rv);
  }

  return mEs->mResultHandler->startElement(aPrefix, aLocalName,
                                           aLowercaseLocalName, aNsID);
}

nsresult txUnknownHandler::startElement(nsAtom* aPrefix,
                                        const nsAString& aLocalName,
                                        const int32_t aNsID) {
  if (!mFlushed) {
    // Make sure that mEs->mResultHandler == this is true, otherwise we'll
    // leak mEs->mResultHandler in createHandlerAndFlush.
    NS_ASSERTION(mEs->mResultHandler == this,
                 "We're leaking mEs->mResultHandler.");

    bool htmlRoot =
        aNsID == kNameSpaceID_None && !aPrefix &&
        aLocalName.Equals(u"html"_ns, nsCaseInsensitiveStringComparator);
    nsresult rv = createHandlerAndFlush(htmlRoot, aLocalName, aNsID);
    NS_ENSURE_SUCCESS(rv, rv);
  }

  return mEs->mResultHandler->startElement(aPrefix, aLocalName, aNsID);
}

nsresult txUnknownHandler::createHandlerAndFlush(bool aHTMLRoot,
                                                 const nsAString& aName,
                                                 const int32_t aNsID) {
  NS_ENSURE_TRUE(mBuffer, NS_ERROR_NOT_INITIALIZED);

  txOutputFormat format;
  format.merge(*(mEs->mStylesheet->getOutputFormat()));
  if (format.mMethod == eMethodNotSet) {
    format.mMethod = aHTMLRoot ? eHTMLOutput : eXMLOutput;
  }

  UniquePtr<txAXMLEventHandler> handler;
  nsresult rv = mEs->mOutputHandlerFactory->createHandlerWith(
      &format, aName, aNsID, getter_Transfers(handler));
  NS_ENSURE_SUCCESS(rv, rv);

  mEs->mOutputHandler = handler.get();
  mEs->mResultHandler = handler.release();
  // Let the executionstate delete us. We need to stay alive because we might
  // need to forward hooks to mEs->mResultHandler if someone is currently
  // flushing a buffer to mEs->mResultHandler.
  mEs->mObsoleteHandler = WrapUnique(this);

  mFlushed = true;

  // Let go of out buffer as soon as we're done flushing it, we're not going
  // to need it anymore from this point on (all hooks get forwarded to
  // mEs->mResultHandler.
  UniquePtr<txResultBuffer> buffer(std::move(mBuffer));
  return buffer->flushToHandler(mEs->mResultHandler);
}