/*
 * Copyright 1999-2004 The Apache Software Foundation.
 *
 * Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */


// Class header file...
#include "NamespacesHandler.hpp"


#include <xalanc/PlatformSupport/StringTokenizer.hpp>
#include <xalanc/PlatformSupport/XalanMessageLoader.hpp>


#include <xalanc/DOMSupport/DOMServices.hpp>


#include "AVT.hpp"
#include "Constants.hpp"
#include "StylesheetConstructionContext.hpp"
#include "StylesheetExecutionContext.hpp"


XALAN_CPP_NAMESPACE_BEGIN


template<class VectorType, class MemberFunctionType>
const typename VectorType::value_type*
find(
			const VectorType&		theVector,
			const XalanDOMString&	theString,
			MemberFunctionType		theMemberFunction)
{
	const typename VectorType::const_iterator	theEnd(theVector.end());
	typename VectorType::const_iterator			theCurrent(theVector.begin());

	while(theCurrent != theEnd)
	{
		if (((*theCurrent).*theMemberFunction)() == theString)
		{
			return &*theCurrent;
		}
		else
		{
			++theCurrent;
		}
	}

	return 0;
}


template<class VectorType, class MemberFunctionType>
typename VectorType::value_type*
findNonConst(
			VectorType&				theVector,
			const XalanDOMString&	theString,
			MemberFunctionType		theMemberFunction)
{
	const typename VectorType::iterator		theEnd(theVector.end());
	typename VectorType::iterator			theCurrent(theVector.begin());

	while(theCurrent != theEnd)
	{
		if (((*theCurrent).*theMemberFunction)() == theString)
		{
			return &*theCurrent;
		}
		else
		{
			++theCurrent;
		}
	}

	return 0;
}


template<class VectorType>
const typename VectorType::value_type*
findByPrefix(
			const VectorType&		theVector,
			const XalanDOMString&	thePrefix)
{
	typedef typename VectorType::value_type		value_type;

	return find(theVector, thePrefix, &value_type::getPrefix);
}


template<class VectorType>
typename VectorType::value_type*
findByPrefixNonConst(
			VectorType&				theVector,
			const XalanDOMString&	thePrefix)
{
	typedef typename VectorType::value_type		value_type;

	return findNonConst(theVector, thePrefix, &value_type::getPrefix);
}


template<class VectorType>
const typename VectorType::value_type*
findByURI(
			const VectorType&		theVector,
			const XalanDOMString&	theNamespaceURI)
{
	typedef typename VectorType::value_type		value_type;

	return find(theVector, theNamespaceURI, &value_type::getURI);
}


template<class VectorType>
bool
addByPrefix(
			StylesheetConstructionContext&	theConstructionContext,
			VectorType&						theVector,
			const XalanDOMString&			thePrefix,
			const XalanDOMString&			theURI)
{
	typedef typename VectorType::value_type		value_type;

	const value_type* const		theEntry =
		findByPrefix(theVector, thePrefix);

	if (theEntry != 0)
	{
		return false;
	}
	else
	{
		theVector.push_back(
			value_type(
				theConstructionContext.getPooledString(thePrefix),
				theConstructionContext.getPooledString(theURI)));

		return true;
	}
}


template<class VectorType>
bool
addOrUpdateByPrefix(
			StylesheetConstructionContext&	theConstructionContext,
			VectorType&						theVector,
			const XalanDOMString&			thePrefix,
			const XalanDOMString&			theURI)
{
	typedef typename VectorType::value_type		value_type;

	value_type* const	theEntry =
		findByPrefixNonConst(theVector, thePrefix);

	if (theEntry == 0)
	{
		theVector.push_back(
			value_type(
				theConstructionContext.getPooledString(thePrefix),
				theConstructionContext.getPooledString(theURI)));

		return true;
	}
	else
	{
		if (theEntry->getURI() == theURI)
		{
			return false;
		}
		else
		{
			theEntry->setURI(theConstructionContext.getPooledString(theURI));

			return true;
		}
	}
}


template<class VectorType>
const XalanDOMString*
findNamespace(
			const VectorType&		theVector,
			const XalanDOMString&	thePrefix)
{
	typedef typename VectorType::value_type		value_type;

	const value_type* const		theEntry =
		findByPrefix(theVector, thePrefix);

	if (theEntry == 0)
	{
		return 0;
	}
	else
	{
		return &theEntry->getURI();
	}
}


const XalanDOMString		NamespacesHandler::Namespace::s_emptyString;


NamespacesHandler::PrefixChecker::PrefixChecker()
{
}


NamespacesHandler::PrefixChecker::~PrefixChecker()
{
}


NamespacesHandler::NamespacesHandler() :
	m_excludedResultPrefixes(),
	m_namespaceDeclarations(),
	m_extensionNamespaceURIs(),
	m_namespaceAliases()
{
}


NamespacesHandler::NamespacesHandler(
			StylesheetConstructionContext&	theConstructionContext,
			const NamespacesHandler&		/* stylesheetNamespacesHandler */,
			const NamespacesStackType&		theCurrentNamespaces,
			const XalanDOMString&			theXSLTNamespaceURI) :
	m_excludedResultPrefixes(),
	m_namespaceDeclarations(),
	m_extensionNamespaceURIs(),
	m_namespaceAliases()
{
	// Go through the namespaces stack in reverse order...
	const NamespacesStackType::const_reverse_iterator	theEnd =
		theCurrentNamespaces.rend();

	NamespacesStackType::const_reverse_iterator		i =
		theCurrentNamespaces.rbegin();

	for(; i != theEnd; ++i)
	{
		// Process each namespace in the current vector...
		const NamespaceVectorType::const_iterator	theVectorEnd =
			(*i).end();

		NamespaceVectorType::const_iterator			j =
			(*i).begin();

		for(; j != theVectorEnd; ++j)
		{
			const NameSpace&		theNamespace = *j;

			const XalanDOMString&	theURI = theNamespace.getURI();

			const XalanDOMString&	thePrefix = theNamespace.getPrefix();

			if(shouldExcludeResultNamespaceNode(
					theXSLTNamespaceURI,
					theURI) == false)
			{
				addByPrefix(
					theConstructionContext,
					m_namespaceDeclarations,
					thePrefix,
					theURI);
			}
			else
			{
				addByPrefix(
					theConstructionContext,
					m_excludedResultPrefixes,
					thePrefix,
					theURI);

				assert(findByPrefix(m_excludedResultPrefixes, thePrefix) != 0 &&
					   findByPrefix(m_excludedResultPrefixes, thePrefix)->getURI() == theURI);
			}
		}
	}
}


NamespacesHandler::~NamespacesHandler()
{
}


void
NamespacesHandler::addExtensionNamespaceURI(
			StylesheetConstructionContext&	theConstructionContext,
			const XalanDOMString&			theURI)
{
	m_extensionNamespaceURIs.push_back(&theConstructionContext.getPooledString(theURI));
}


const XalanDOMString*
NamespacesHandler::getNamespace(const XalanDOMString&	thePrefix) const
{
	const NamespacesVectorType::value_type*		theNamespace =
		findByPrefix(m_excludedResultPrefixes, thePrefix);

	if (theNamespace != 0)
	{
		return &theNamespace->getURI();
	}
	else
	{
		return findNamespace(m_namespaceDeclarations, thePrefix);
	}
}


void
NamespacesHandler::copyNamespaceAliases(const NamespacesHandler&	parentNamespacesHandler)
{
	copyNamespaceAliases(parentNamespacesHandler.m_namespaceAliases);
}


const XalanDOMString*
NamespacesHandler::getNamespaceAlias(const XalanDOMString&		theStylesheetNamespace) const
{
	if (m_namespaceAliases.empty() == true)
	{
		return 0;
	}
	else
	{
		const NamespaceAliasesMapType::const_iterator	i =
						m_namespaceAliases.find(&theStylesheetNamespace);

		if (i != m_namespaceAliases.end())
		{
			return (*i).second;
		}
		else
		{
			return 0;
		}
	}
}


void
NamespacesHandler::setNamespaceAlias(
			StylesheetConstructionContext&	theConstructionContext,
			const XalanDOMString&			theStylesheetNamespace,
			const XalanDOMString&			theResultNamespace)
{
	m_namespaceAliases[&theConstructionContext.getPooledString(theStylesheetNamespace)] =
		&theConstructionContext.getPooledString(theResultNamespace);
}


void
NamespacesHandler::processExcludeResultPrefixes(
		StylesheetConstructionContext&	theConstructionContext,
		const XalanDOMChar*				theValue,
		const NamespacesStackType&		theCurrentNamespaces)
{
	typedef StylesheetConstructionContext::GetAndReleaseCachedString	GetAndReleaseCachedString;

	StringTokenizer		tokenizer(
					theValue,
					Constants::DEFAULT_WHITESPACE_SEPARATOR_STRING);

	const GetAndReleaseCachedString		theGuard(theConstructionContext);

	XalanDOMString&		thePrefix = theGuard.get();

    while(tokenizer.hasMoreTokens() == true)
    {
		 tokenizer.nextToken(thePrefix);

		if(equalsIgnoreCaseASCII(thePrefix, Constants::ATTRVAL_DEFAULT_PREFIX) == true)
		{
			thePrefix.clear();
		}

		const XalanDOMString* const		theNamespaceURI =
			XalanQName::getNamespaceForPrefix(theCurrentNamespaces, thePrefix);

		if(theNamespaceURI == 0)
		{
			theConstructionContext.error(
				XalanMessageLoader::getMessage(
					XalanMessages::PrefixMustResolveToNamespace_1Param,
					thePrefix));
		}

		addOrUpdateByPrefix(
			theConstructionContext,
			m_excludedResultPrefixes,
			thePrefix,
			*theNamespaceURI);

		assert(findByPrefix(m_excludedResultPrefixes, thePrefix) != 0 &&
			   findByPrefix(m_excludedResultPrefixes, thePrefix)->getURI() == *theNamespaceURI);
    }
}


void
NamespacesHandler::processExtensionElementPrefixes(
			StylesheetConstructionContext&	theConstructionContext,
			const XalanDOMChar*				theValue,
			const NamespacesStackType&		theCurrentNamespaces)
{
	typedef StylesheetConstructionContext::GetAndReleaseCachedString	GetAndReleaseCachedString;

	StringTokenizer		tokenizer(
					theValue,
					Constants::DEFAULT_WHITESPACE_SEPARATOR_STRING);

	const GetAndReleaseCachedString		theGuard(theConstructionContext);

	XalanDOMString&		thePrefix = theGuard.get();

	while(tokenizer.hasMoreTokens() == true)
    {
		tokenizer.nextToken(thePrefix);

		if(equalsIgnoreCaseASCII(thePrefix, Constants::ATTRVAL_DEFAULT_PREFIX) == true)
		{
			thePrefix.clear();
		}

		const XalanDOMString* const		theNamespace =
			XalanQName::getNamespaceForPrefix(theCurrentNamespaces, thePrefix);

		if(theNamespace == 0)
		{
			theConstructionContext.error(
				XalanMessageLoader::getMessage(
					XalanMessages::PrefixMustResolveToNamespace_1Param,
					thePrefix));
		}

		assert(theNamespace != 0);

		m_extensionNamespaceURIs.push_back(&theConstructionContext.getPooledString(*theNamespace));
    }
}


void
NamespacesHandler::postConstruction(
			StylesheetConstructionContext&	theConstructionContext,
			bool							fProcessNamespaceAliases,
			const XalanDOMString&			theElementName,
			const NamespacesHandler*		parentNamespacesHandler,
			const PrefixChecker*			prefixChecker)
{
	// Copy everything from the parent handler, if there is one...
	if (parentNamespacesHandler != 0)
	{
		copyNamespaceAliases(parentNamespacesHandler->m_namespaceAliases);

		copyExtensionNamespaceURIs(parentNamespacesHandler->m_extensionNamespaceURIs);

		copyExcludeResultPrefixes(parentNamespacesHandler->m_excludedResultPrefixes);
	}

	// Figure out the prefix of the owning element, to make sure we
	// don't exclude its prefix.
	const XalanDOMString::size_type		indexOfNSSep = indexOf(theElementName, XalanUnicode::charColon);

	typedef StylesheetConstructionContext::GetAndReleaseCachedString	GetAndReleaseCachedString;

	const GetAndReleaseCachedString		theGuard(theConstructionContext);

	XalanDOMString&		thePrefix = theGuard.get();

	if (indexOfNSSep < length(theElementName))
	{
		substring(theElementName, thePrefix, 0, indexOfNSSep);
	}

	processExcludeResultPrefixes(theConstructionContext, thePrefix, prefixChecker);

	if (fProcessNamespaceAliases == true)
	{
		// $$ ToDo: Does this happen before or after exclude-result-prefixes?
		processNamespaceAliases();
	}

	createResultAttributeNames(theConstructionContext);
}


NamespacesHandler&
NamespacesHandler::operator=(const NamespacesHandler&	theRHS)
{
	if (&theRHS != this)
	{
		m_excludedResultPrefixes = theRHS.m_excludedResultPrefixes;

		m_namespaceDeclarations = theRHS.m_namespaceDeclarations;

		m_extensionNamespaceURIs = theRHS.m_extensionNamespaceURIs;

		m_namespaceAliases = theRHS.m_namespaceAliases;
	}

	return *this;
}


bool
NamespacesHandler::shouldExcludeResultNamespaceNode(
			const XalanDOMString&	theXSLTNamespaceURI,
			const XalanDOMString&	theURI) const
{
	// These are commone namespaces that are always excluded...
	if(equals(theURI, theXSLTNamespaceURI)
			|| isExtensionNamespaceURI(theURI) == true
			|| equals(theURI, DOMServices::s_XMLNamespaceURI))
	{
		return true;
	}
	else if (isExcludedNamespaceURI(theURI) == true)
	{
		// It was found in the excluded result prefixes URIs...
		return true;
	}
	else
	{
		return false;
	}
}


void
NamespacesHandler::outputResultNamespaces(
			StylesheetExecutionContext&		theExecutionContext,
			bool							supressDefault) const
{
	// Write out the namespace declarations...
	if (m_namespaceDeclarations.empty() == false)
	{
		const NamespaceExtendedVectorType::const_iterator	theEnd =
				m_namespaceDeclarations.end();

		NamespaceExtendedVectorType::const_iterator	i =
				m_namespaceDeclarations.begin();

		for(; i != theEnd; ++i)
		{
			const NamespaceExtended&	theNamespace = *i;

			const XalanDOMString&		thePrefix = theNamespace.getPrefix();

			// If we're not supposed to suppress the default namespace, or
			// there's a prefix (so it's not the default), we can continue
			// to see if we need to add the result namespace.
			if (supressDefault == false ||
				length(thePrefix) != 0)
			{
				const XalanDOMString&		theResultURI = theNamespace.getURI();
				assert(length(theNamespace.getResultAttributeName()) > 0);

				// Get the any namespace declaration currently active for the
				// prefix.
				const XalanDOMString* const		desturi =
					theExecutionContext.getResultNamespaceForPrefix(thePrefix);

				// Is there already an active namespace declaration?
				if(desturi == 0 || !equals(theResultURI, *desturi))
				{
					// No, so add one...
					theExecutionContext.addResultAttribute(theNamespace.getResultAttributeName(), theResultURI);
				}
			}
		}
	}
}


bool
NamespacesHandler::isExcludedNamespaceURI(const XalanDOMString&		theNamespaceURI) const
{
	return findByURI(m_excludedResultPrefixes, theNamespaceURI) != 0 ? true : false; 
}


bool
NamespacesHandler::findString(
			const XalanDOMString&					theString,
			const XalanDOMStringPointerVectorType&	theVector)
{
	const XalanDOMStringPointerVectorType::const_iterator	theEnd = theVector.end();
	XalanDOMStringPointerVectorType::const_iterator			theCurrent = theVector.begin();

	while(theCurrent != theEnd)
	{
		assert(*theCurrent != 0);

		const XalanDOMString* const		theCurrentString = *theCurrent;

		if (theString == *theCurrentString)
		{
			return true;
		}

		++theCurrent;
	}

	return false;
}


void
NamespacesHandler::clear()
{
	m_excludedResultPrefixes.clear();

	m_namespaceDeclarations.clear();

	m_extensionNamespaceURIs.clear();

	m_namespaceAliases.clear();
}


void
NamespacesHandler::swap(NamespacesHandler&	theOther)
{
	m_excludedResultPrefixes.swap(theOther.m_excludedResultPrefixes);

	m_namespaceDeclarations.swap(theOther.m_namespaceDeclarations);

	m_extensionNamespaceURIs.swap(theOther.m_extensionNamespaceURIs);

	m_namespaceAliases.swap(theOther.m_namespaceAliases);
}


void
NamespacesHandler::createResultAttributeNames(StylesheetConstructionContext&	theConstructionContext)
{
	// Go through all of the result namespaces and create the attribute
	// name that will be used when they're written to the result tree.
	// This is more efficient if the stylesheet is used multiple times.
	if (m_namespaceDeclarations.empty() == false)
	{
		const NamespaceExtendedVectorType::iterator	theEnd =
				m_namespaceDeclarations.end();

		NamespaceExtendedVectorType::iterator		i =
				m_namespaceDeclarations.begin();

		XalanDOMString	theName;

		for(; i != theEnd; ++i)
		{
			NamespaceExtended&		theNamespace = *i;

			const XalanDOMString&	thePrefix = theNamespace.getPrefix();

			if (isEmpty(thePrefix) == false)
			{
				// Create a name of the form xmlns:prefix, where "prefix" is the
				// text of the prefix.
				// Reserve the appropriate amount of space in the string.
				reserve(theName, DOMServices::s_XMLNamespaceWithSeparatorLength + length(thePrefix) + 1);

				theName = DOMServices::s_XMLNamespaceWithSeparator;
				theName += thePrefix;

				theNamespace.setResultAttributeName(theConstructionContext.getPooledString(theName));
			}
			else
			{
				// It's the default namespace...
				theNamespace.setResultAttributeName(DOMServices::s_XMLNamespace);
			}
		}
	}
}


void
NamespacesHandler::processExcludeResultPrefixes(
			StylesheetConstructionContext&	theConstructionContext,
			const XalanDOMString&			theElementPrefix,
			const PrefixChecker*			prefixChecker)
{
	if (m_excludedResultPrefixes.empty() == false)
	{
		NamespaceExtendedVectorType::iterator		i =
				m_namespaceDeclarations.begin();

		// Check for any result prefixes we should exclude...
		while(i != m_namespaceDeclarations.end())
		{
			const Namespace&		theNamespace = *i;

			const XalanDOMString&	thePrefix = theNamespace.getPrefix();
			const XalanDOMString&	theURI = theNamespace.getURI();

			// We can never exclude the prefix of our owner element, so
			// check that first...
			if (equals(thePrefix, theElementPrefix) == false &&
				(prefixChecker == 0 || prefixChecker->isActive(thePrefix) == false) &&
				(isExcludedNamespaceURI(theURI) == true ||
				 isExtensionNamespaceURI(theURI) == true))
			{
				// Add it to the excluded prefixes, in case we need it later...
				m_excludedResultPrefixes.push_back(
						NamespacesVectorType::value_type(
							theConstructionContext.getPooledString(thePrefix),
							theConstructionContext.getPooledString(theURI)));

				// It's excluded, so remove it...
				i = m_namespaceDeclarations.erase(i);
			}
			else
			{
				++i;
			}
		}
	}
}


void
NamespacesHandler::processNamespaceAliases()
{
	if (m_namespaceDeclarations.empty() == false)
	{
		const NamespaceExtendedVectorType::iterator		theEnd =
				m_namespaceDeclarations.end();

		NamespaceExtendedVectorType::iterator	i =
				m_namespaceDeclarations.begin();

		// Look at everyone of my namespaces for an alias, and substitute the
		// alias as appropriate...
		for(; i != theEnd; ++i)
		{
			Namespace&	theNamespace = *i;

			const XalanDOMString&			theURI =
						theNamespace.getURI();

			const XalanDOMString* const		theAlias =
						getNamespaceAlias(theURI);

			// Is there a local alias?
			if (theAlias != 0)
			{
				// Yup, so use it...
				theNamespace.setURI(*theAlias);
			}
		}
	}
}


void
NamespacesHandler::copyNamespaceAliases(const NamespaceAliasesMapType&	theNamespaceAliases)
{
	if (theNamespaceAliases.empty() == false)
	{
		if (m_namespaceAliases.empty() == true)
		{
			m_namespaceAliases = theNamespaceAliases;
		}
		else
		{
			const NamespaceAliasesMapType::const_iterator	theEnd =
					theNamespaceAliases.end();

			NamespaceAliasesMapType::const_iterator		i =
					theNamespaceAliases.begin();

			// Add them in...
			while(i != theEnd)
			{
				m_namespaceAliases.insert(*i);

				++i;
			}
		}
	}
}


void
NamespacesHandler::copyExtensionNamespaceURIs(const XalanDOMStringPointerVectorType&	theExtensionNamespaceURIs)
{
	if (theExtensionNamespaceURIs.empty() == false)
	{
		if (m_extensionNamespaceURIs.empty() == true)
		{
			m_extensionNamespaceURIs = theExtensionNamespaceURIs;
		}
		else
		{
			const XalanDOMStringPointerVectorType::const_iterator	theEnd =
					theExtensionNamespaceURIs.end();

			XalanDOMStringPointerVectorType::const_iterator	i =
					theExtensionNamespaceURIs.begin();

			// Add them in...
			while(i != theEnd)
			{
				assert(*i != 0);

				if (isExtensionNamespaceURI(**i) == false)
				{
					m_extensionNamespaceURIs.push_back(*i);
				}

				++i;
			}
		}
	}
}


void
NamespacesHandler::copyExcludeResultPrefixes(const NamespacesVectorType&	theExcludeResultPrefixes)
{
	if (theExcludeResultPrefixes.empty() == false)
	{
		if (m_excludedResultPrefixes.empty() == true)
		{
			m_excludedResultPrefixes = theExcludeResultPrefixes;
		}
		else
		{
			const NamespacesVectorType::const_iterator	theEnd =
					theExcludeResultPrefixes.end();

			NamespacesVectorType::const_iterator	i =
					theExcludeResultPrefixes.begin();

			// Add them in...
			while(i != theEnd)
			{
				if (findByPrefix(m_excludedResultPrefixes, (*i).getPrefix()) == 0)
				{
					m_excludedResultPrefixes.push_back(*i);
				}

				++i;
			}
		}
	}
}


XALAN_CPP_NAMESPACE_END