/*
 * 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.
 */
#include "ElemForEach.hpp"


#include <algorithm>
#include <cassert>


#include <xercesc/sax/AttributeList.hpp>


#include <xalanc/Include/STLHelper.hpp>


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


#include <xalanc/XPath/XPath.hpp>


#include "ElemSort.hpp"
#include "NodeSorter.hpp"
#include "SelectionEvent.hpp"
#include "StylesheetConstructionContext.hpp"
#include "StylesheetExecutionContext.hpp"


XALAN_CPP_NAMESPACE_BEGIN


ElemForEach::ElemForEach(
			StylesheetConstructionContext&	constructionContext,
			Stylesheet&						stylesheetTree,
			const AttributeListType&		atts,
			int								lineNumber,
			int								columnNumber) :
	ElemTemplateElement(constructionContext,
						stylesheetTree,
						lineNumber,
						columnNumber,
						StylesheetConstructionContext::ELEMNAME_FOR_EACH),
	m_selectPattern(0),
	m_sortElems(),
	m_sortElemsCount(0)
{
	const unsigned int	nAttrs = atts.getLength();
		
	for(unsigned int i = 0; i < nAttrs; i++)
	{
		const XalanDOMChar*	const	aname = atts.getName(i);

		if(equals(aname, Constants::ATTRNAME_SELECT))
		{
			m_selectPattern = constructionContext.createXPath(getLocator(), atts.getValue(i), *this);
		}
		else if(!(isAttrOK(aname, atts, i, constructionContext) ||
				processSpaceAttr(aname, atts, i, constructionContext)))
		{
			constructionContext.error(
					XalanMessageLoader::getMessage(
						XalanMessages::TemplateHasIllegalAttribute_2Param,
							Constants::ELEMNAME_FOREACH_WITH_PREFIX_STRING.c_str(),
							aname),
					0,
					this);
		}
	}

	if(0 == m_selectPattern)
	{
		constructionContext.error(
			XalanMessageLoader::getMessage(
				XalanMessages::TemplateMustHaveAttribute_2Param,
				Constants::ELEMNAME_FOREACH_WITH_PREFIX_STRING,
				Constants::ATTRNAME_SELECT),
			0,
			this);
	}
}


ElemForEach::ElemForEach(
			StylesheetConstructionContext&	constructionContext,
			Stylesheet&						stylesheetTree,
			int								lineNumber,
			int								columnNumber,
			int								xslToken) :
	ElemTemplateElement(constructionContext,
						stylesheetTree,
						lineNumber,
						columnNumber,
						xslToken),
	m_selectPattern(0),
	m_sortElems(),
	m_sortElemsCount(0)
{
}


ElemForEach::~ElemForEach()
{
	XALAN_USING_STD(for_each)

	for_each(m_sortElems.begin(),
			 m_sortElems.end(),
			 DeleteFunctor<ElemSort>());
}


void
ElemForEach::processSortElement(
			StylesheetConstructionContext&	constructionContext,
			Stylesheet&						theStylesheet,
			const AttributeListType&		atts,
			const LocatorType*				locator)
{
	const int	lineNumber = XalanLocator::getLineNumber(locator);
	const int	columnNumber = XalanLocator::getColumnNumber(locator);

	m_sortElems.reserve(m_sortElems.size() + 1);

	ElemSort* sortElem = new ElemSort(
		constructionContext,
		theStylesheet,
		atts,
		lineNumber,
		columnNumber);

	m_sortElems.push_back(sortElem);
}


const XalanDOMString&
ElemForEach::getElementName() const
{
	return Constants::ELEMNAME_FOREACH_WITH_PREFIX_STRING;
}


void
ElemForEach::postConstruction(
			StylesheetConstructionContext&	constructionContext,
			const NamespacesHandler&		theParentHandler)
{
	ElemTemplateElement::postConstruction(constructionContext, theParentHandler);

	m_sortElemsCount = m_sortElems.size();
}


#if !defined(XALAN_RECURSIVE_STYLESHEET_EXECUTION)
const ElemTemplateElement*
ElemForEach::startElement(StylesheetExecutionContext&		executionContext) const
{
	assert(executionContext.getCurrentNode() != 0);

	if (hasChildren() == true)
	{
		executionContext.pushCurrentTemplate(0);
		const NodeRefListBase * nodeList = createSelectedAndSortedNodeList(
				executionContext);
		executionContext.createAndPushNodesToTransformList(nodeList);
		executionContext.pushContextNodeList(*nodeList);
		
		XalanNode* currentNode = executionContext.getNextNodeToTransform();
		if (currentNode == 0)
		{
			return 0;
		}
		executionContext.pushCurrentNode(currentNode);

		return beginExecuteChildren(executionContext);	
	}
	
	return 0;
}


const ElemTemplateElement*
ElemForEach::getNextChildElemToExecute(
				   StylesheetExecutionContext& executionContext,
				   const ElemTemplateElement* currentElem) const
{
	ElemTemplateElement* nextElement = currentElem->getNextSiblingElem();

	if (nextElement != 0)
	{
		return nextElement;
	}

	executionContext.popCurrentNode();


	XalanNode * nextNode = executionContext.getNextNodeToTransform();

	if (nextNode == 0)
	{
		return 0;
	}

	executionContext.pushCurrentNode(nextNode);
	endExecuteChildren(executionContext);
	return beginExecuteChildren(executionContext);
}


void
ElemForEach::endElement(StylesheetExecutionContext&		executionContext) const
{
	if (hasChildren() == true)
	{
		endExecuteChildren(executionContext);
		executionContext.popNodesToTransformList();
		executionContext.popContextNodeList();
		releaseSelectedAndSortedNodeList(executionContext);
		executionContext.popCurrentTemplate();
	}	
}


const NodeRefListBase*
ElemForEach::createSelectedAndSortedNodeList(
			StylesheetExecutionContext&		executionContext) const 
{
	assert(m_selectPattern != 0);

	typedef StylesheetExecutionContext::SetAndRestoreCurrentStackFrameIndex		SetAndRestoreCurrentStackFrameIndex;

	MutableNodeRefList& selectedNodeList = executionContext.createAndPushMutableNodeRefList();	

	XObjectPtr xobjectResult;
		
	const NodeRefListBase*	nodesToTransform = 0;

	{
		xobjectResult = m_selectPattern->execute(
						*this,
						executionContext,
						selectedNodeList);

		if (xobjectResult.null() == true)
		{
			nodesToTransform = &selectedNodeList;
		}
		else
		{
			nodesToTransform = &xobjectResult->nodeset();
		}
	}
	executionContext.pushXObjectPtr(xobjectResult);

	if(0 != executionContext.getTraceListeners())
	{
		executionContext.fireSelectEvent(
				SelectionEvent(
					executionContext, 
					executionContext.getCurrentNode(),
					*this,
					StaticStringToDOMString(XALAN_STATIC_UCODE_STRING("select")),
					*m_selectPattern,
					*nodesToTransform));
	}

	if (m_sortElemsCount > 0) 
		//&& nodesToTransform->getLength() > 1)
	{
		MutableNodeRefList& sortedNodeList = executionContext.createAndPushMutableNodeRefList();

		nodesToTransform = sortChildren(
				executionContext,
				*nodesToTransform,
				sortedNodeList);
	}

	return nodesToTransform;
}


void
ElemForEach::releaseSelectedAndSortedNodeList(
		StylesheetExecutionContext& executionContext) const
{
	executionContext.popXObjectPtr();
	executionContext.releaseAndPopMutableNodeRefList();
	if (m_sortElemsCount > 0)
	{
		executionContext.releaseAndPopMutableNodeRefList();
	}
}


const NodeRefListBase*
ElemForEach::sortChildren(	
			StylesheetExecutionContext&		executionContext,
			const NodeRefListBase&			selectedNodeList,
			MutableNodeRefList&				sortedNodeList) const
{
	typedef NodeSorter::NodeSortKeyVectorType					NodeSortKeyVectorType;
	typedef StylesheetExecutionContext::SetAndRestoreCurrentStackFrameIndex		SetAndRestoreCurrentStackFrameIndex;
	typedef StylesheetExecutionContext::ContextNodeListPushAndPop				ContextNodeListPushAndPop;
	
	NodeSorter* sorter = executionContext.getNodeSorter();

	NodeSortKeyVectorType&	keys = sorter->getSortKeys();
	assert(keys.empty() == true);

	CollectionClearGuard<NodeSortKeyVectorType>		guard(keys);

	// Reserve the space now...
	keys.reserve(m_sortElemsCount);

	// Get some temporary strings to use for evaluting the AVTs...
	StylesheetExecutionContext::GetAndReleaseCachedString	theTemp1(executionContext);

	XalanDOMString&		langString = theTemp1.get();

	StylesheetExecutionContext::GetAndReleaseCachedString	theTemp2(executionContext);

	XalanDOMString&		scratchString = theTemp2.get();

	// March backwards, performing a sort on each xsl:sort child.
	// Probably not the most efficient method.
	for(SortElemsVectorType::size_type	i = 0; i < m_sortElemsCount; i++)
	{
		const ElemSort* const	sort = m_sortElems[i];
		assert(sort != 0);

		const AVT* avt = sort->getLangAVT();

		if(0 != avt)
		{
			avt->evaluate(langString, *this, executionContext);
		}

		avt = sort->getDataTypeAVT();

		if(0 != avt)
		{
			avt->evaluate(scratchString, *this, executionContext);
		}			

		bool	treatAsNumbers = false;

		if (isEmpty(scratchString) == false)
		{
			if (equals(scratchString, Constants::ATTRVAL_DATATYPE_NUMBER) == true)
			{
				treatAsNumbers = true;
			}
			else if (equals(scratchString, Constants::ATTRVAL_DATATYPE_TEXT) == false)
			{
				const XalanQNameByValue		theQName(scratchString, this);

				if (theQName.getNamespace().length() == 0)
				{
					executionContext.error(
						XalanMessageLoader::getMessage(XalanMessages::XslSortDataTypeMustBe),
						executionContext.getCurrentNode(),
						sort->getLocator());
				}
				else
				{
					executionContext.warn(
						XalanMessageLoader::getMessage(XalanMessages::XslSortHasUnlnownDataType),
						executionContext.getCurrentNode(),
						sort->getLocator());
				}
			}
		}

		clear(scratchString);

		avt = sort->getOrderAVT();

		if(0 != avt)
		{
			avt->evaluate(scratchString, *this, executionContext);
		}			

		bool	descending = false;
		
		if (isEmpty(scratchString) == false)
		{
			if (equals(scratchString, Constants::ATTRVAL_ORDER_DESCENDING) == true)
			{
				descending = true;
			}
			else if (equals(scratchString, Constants::ATTRVAL_ORDER_ASCENDING) == false)
			{
				executionContext.error(
					XalanMessageLoader::getMessage(XalanMessages::XslSortMustBeAscendOrDescend),
					executionContext.getCurrentNode(),
					sort->getLocator());
			}
		}

		clear(scratchString);

		avt = sort->getCaseOrderAVT();

		if(0 != avt)
		{
			avt->evaluate(scratchString, *this, executionContext);
		}			

		XalanCollationServices::eCaseOrder	caseOrder = XalanCollationServices::eDefault;

		if (isEmpty(scratchString) == false)
		{
			if (equals(scratchString, Constants::ATTRVAL_CASEORDER_UPPER) == true)
			{
				caseOrder = XalanCollationServices::eUpperFirst;
			}
			else if (equals(scratchString, Constants::ATTRVAL_CASEORDER_LOWER) == true)
			{
				caseOrder = XalanCollationServices::eLowerFirst;
			}
			else
			{
				executionContext.error(
					XalanMessageLoader::getMessage(XalanMessages::XslSortCaseOrderMustBe),
					executionContext.getCurrentNode(),
					sort->getLocator());
			}
		}

		clear(scratchString);

		keys.push_back(
				NodeSortKey(
					executionContext,
					sort->getSelectPattern(),
					treatAsNumbers,
					descending,
					caseOrder,
					langString,
					*this));
	}

	sortedNodeList = selectedNodeList;

	{
		ContextNodeListPushAndPop	theContextNodeListPushAndPop(
				executionContext,
				selectedNodeList);

		sorter->sort(executionContext, sortedNodeList);
	}

	return &sortedNodeList;
}
#endif


#if defined(XALAN_RECURSIVE_STYLESHEET_EXECUTION)
void
ElemForEach::execute(StylesheetExecutionContext&	executionContext) const
{
	assert(m_selectPattern != 0);
	assert(executionContext.getCurrentNode() != 0);

	StylesheetExecutionContext::PushAndPopCurrentTemplate	thePushAndPop(executionContext, 0);

	if (hasChildren() == true)
	{
		transformSelectedChildren(
			executionContext,
			this);
	}
}


void
ElemForEach::transformSelectedChildren(
			StylesheetExecutionContext&		executionContext,
			const ElemTemplateElement*		theTemplate) const
{
	assert(m_selectPattern != 0);
	assert(m_sortElemsCount == m_sortElems.size());

	if (m_sortElemsCount == 0)
	{
		selectAndSortChildren(
					executionContext,
					theTemplate,
					0,
					executionContext.getCurrentStackFrameIndex());
	}
	else
	{
		typedef NodeSorter::NodeSortKeyVectorType					NodeSortKeyVectorType;
		typedef StylesheetExecutionContext::BorrowReturnNodeSorter	BorrowReturnNodeSorter;

		BorrowReturnNodeSorter	sorter(executionContext);

		NodeSortKeyVectorType&	keys = sorter->getSortKeys();
		assert(keys.empty() == true);

		CollectionClearGuard<NodeSortKeyVectorType>		guard(keys);

		// Reserve the space now...
		keys.reserve(m_sortElemsCount);

		// Get some temporary strings to use for evaluting the AVTs...
		StylesheetExecutionContext::GetAndReleaseCachedString	theTemp1(executionContext);

		XalanDOMString&		langString = theTemp1.get();

		StylesheetExecutionContext::GetAndReleaseCachedString	theTemp2(executionContext);

		XalanDOMString&		scratchString = theTemp2.get();

		// March backwards, performing a sort on each xsl:sort child.
		// Probably not the most efficient method.
		for(SortElemsVectorType::size_type	i = 0; i < m_sortElemsCount; i++)
		{
			const ElemSort* const	sort = m_sortElems[i];
			assert(sort != 0);

			const AVT* avt = sort->getLangAVT();

			if(0 != avt)
			{
				avt->evaluate(langString, *this, executionContext);
			}

			avt = sort->getDataTypeAVT();

			if(0 != avt)
			{
				avt->evaluate(scratchString, *this, executionContext);
			}			

			bool	treatAsNumbers = false;

			if (isEmpty(scratchString) == false)
			{
				if (equals(scratchString, Constants::ATTRVAL_DATATYPE_NUMBER) == true)
				{
					treatAsNumbers = true;
				}
				else if (equals(scratchString, Constants::ATTRVAL_DATATYPE_TEXT) == false)
				{
					const XalanQNameByValue		theQName(scratchString, this);

					if (theQName.getNamespace().length() == 0)
					{
						executionContext.error(
							XalanMessageLoader::getMessage(XalanMessages::XslSortDataTypeMustBe),
							executionContext.getCurrentNode(),
							sort->getLocator());
					}
					else
					{
						executionContext.warn(
							XalanMessageLoader::getMessage(XalanMessages::XslSortHasUnlnownDataType),
							executionContext.getCurrentNode(),
							sort->getLocator());
					}
				}
			}

			clear(scratchString);

			avt = sort->getOrderAVT();

			if(0 != avt)
			{
				avt->evaluate(scratchString, *this, executionContext);
			}			

			bool	descending = false;
			
			if (isEmpty(scratchString) == false)
			{
				if (equals(scratchString, Constants::ATTRVAL_ORDER_DESCENDING) == true)
				{
					descending = true;
				}
				else if (equals(scratchString, Constants::ATTRVAL_ORDER_ASCENDING) == false)
				{
					executionContext.error(
						XalanMessageLoader::getMessage(XalanMessages::XslSortMustBeAscendOrDescend),
						executionContext.getCurrentNode(),
						sort->getLocator());
				}
			}

			clear(scratchString);

			avt = sort->getCaseOrderAVT();

			if(0 != avt)
			{
				avt->evaluate(scratchString, *this, executionContext);
			}			

			XalanCollationServices::eCaseOrder	caseOrder = XalanCollationServices::eDefault;

			if (isEmpty(scratchString) == false)
			{
				if (equals(scratchString, Constants::ATTRVAL_CASEORDER_UPPER) == true)
				{
					caseOrder = XalanCollationServices::eUpperFirst;
				}
				else if (equals(scratchString, Constants::ATTRVAL_CASEORDER_LOWER) == true)
				{
					caseOrder = XalanCollationServices::eLowerFirst;
				}
				else
				{
					executionContext.error(
						XalanMessageLoader::getMessage(XalanMessages::XslSortCaseOrderMustBe),
						executionContext.getCurrentNode(),
						sort->getLocator());
				}
			}

			clear(scratchString);

			keys.push_back(
					NodeSortKey(
						executionContext,
						sort->getSelectPattern(),
						treatAsNumbers,
						descending,
						caseOrder,
						langString,
						*this));
		}

		selectAndSortChildren(
					executionContext,
					theTemplate,
					sorter.get(),
					executionContext.getCurrentStackFrameIndex());
	}
}


void
ElemForEach::selectAndSortChildren(
			StylesheetExecutionContext&		executionContext,
			const ElemTemplateElement*		theTemplate,
			NodeSorter*						sorter,
			int								selectStackFrameIndex) const
{
	typedef StylesheetExecutionContext::SetAndRestoreCurrentStackFrameIndex		SetAndRestoreCurrentStackFrameIndex;

	assert(m_selectPattern != 0);

	typedef XPathExecutionContext::BorrowReturnMutableNodeRefList	BorrowReturnMutableNodeRefList;

	BorrowReturnMutableNodeRefList	theGuard(executionContext);

	const NodeRefListBase*	sourceNodes = 0;

	XObjectPtr				xobjectResult;

	{
		SetAndRestoreCurrentStackFrameIndex		theSetAndRestore(
					executionContext,
					selectStackFrameIndex);

		xobjectResult = m_selectPattern->execute(
						*this,
						executionContext,
						*theGuard);

		if (xobjectResult.null() == true)
		{
			sourceNodes = &*theGuard;
		}
		else
		{
			theGuard.release();

			sourceNodes = &xobjectResult->nodeset();
		}
	}

	if(0 != executionContext.getTraceListeners())
	{
		executionContext.fireSelectEvent(
				SelectionEvent(
					executionContext, 
					executionContext.getCurrentNode(),
					*this,
					StaticStringToDOMString(XALAN_STATIC_UCODE_STRING("select")),
					*m_selectPattern,
					*sourceNodes));
	}

	const NodeRefListBase::size_type	nNodes = sourceNodes->getLength();

	if (nNodes > 0)
	{
		// If there's not NodeSorter, or we've only selected one node,
		// then just do the transform...
		if (sorter == 0 || nNodes == 1)
		{
			transformSelectedChildren(
				executionContext,
				theTemplate,
				*sourceNodes,
				nNodes);
		}
		else
		{
			typedef StylesheetExecutionContext::SetAndRestoreCurrentStackFrameIndex		SetAndRestoreCurrentStackFrameIndex;
			typedef StylesheetExecutionContext::ContextNodeListPushAndPop				ContextNodeListPushAndPop;
			typedef StylesheetExecutionContext::BorrowReturnMutableNodeRefList			BorrowReturnMutableNodeRefList;

			BorrowReturnMutableNodeRefList	sortedSourceNodes(executionContext);

			*sortedSourceNodes = *sourceNodes;

			{
				SetAndRestoreCurrentStackFrameIndex		theStackFrameSetAndRestore(
						executionContext,
						selectStackFrameIndex);

				ContextNodeListPushAndPop	theContextNodeListPushAndPop(
						executionContext,
						*sourceNodes);

				sorter->sort(executionContext, *sortedSourceNodes);
			}

			transformSelectedChildren(
				executionContext,
				theTemplate,
				*sortedSourceNodes,
				nNodes);
		}
	}
}


void
ElemForEach::transformSelectedChildren(
			StylesheetExecutionContext&		executionContext,
			const ElemTemplateElement*		theTemplate,
			const NodeRefListBase&			sourceNodes,
			NodeRefListBase::size_type		sourceNodesCount) const
{
	if(executionContext.getTraceSelects() == true)
	{
		executionContext.traceSelect(
			*this,
			sourceNodes,
			m_selectPattern);
	}

	// Create an object to set and restore the context node list...
	const StylesheetExecutionContext::ContextNodeListPushAndPop		theContextNodeLisPushAndPop(
				executionContext,
				sourceNodes);

	for(NodeRefListBase::size_type i = 0; i < sourceNodesCount; i++) 
	{
		XalanNode* const		childNode = sourceNodes.item(i);
		assert(childNode != 0);

		transformChild(
				executionContext,
				*this,
				theTemplate,
				childNode);
	}
}
#endif


const XPath*
ElemForEach::getXPath(unsigned int	index) const
{
	return index == 0 ? m_selectPattern : 0;
}


XALAN_CPP_NAMESPACE_END