/*******************************************************************************
 * Copyright (c) 2004 Actuate Corporation.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *  Actuate Corporation  - initial API and implementation
 *******************************************************************************/

package org.eclipse.birt.report.model.writer;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.eclipse.birt.core.data.ExpressionUtil;
import org.eclipse.birt.core.data.IColumnBinding;
import org.eclipse.birt.core.exception.BirtException;
import org.eclipse.birt.report.model.api.StructureFactory;
import org.eclipse.birt.report.model.api.elements.structures.ComputedColumn;
import org.eclipse.birt.report.model.api.util.StringUtil;
import org.eclipse.birt.report.model.api.validators.DataColumnNameValidator;
import org.eclipse.birt.report.model.core.ContainerSlot;
import org.eclipse.birt.report.model.core.DesignElement;
import org.eclipse.birt.report.model.core.Module;
import org.eclipse.birt.report.model.elements.DataItem;
import org.eclipse.birt.report.model.elements.ExtendedItem;
import org.eclipse.birt.report.model.elements.GridItem;
import org.eclipse.birt.report.model.elements.GroupElement;
import org.eclipse.birt.report.model.elements.ImageItem;
import org.eclipse.birt.report.model.elements.Label;
import org.eclipse.birt.report.model.elements.ListGroup;
import org.eclipse.birt.report.model.elements.ListItem;
import org.eclipse.birt.report.model.elements.ListingElement;
import org.eclipse.birt.report.model.elements.ScalarParameter;
import org.eclipse.birt.report.model.elements.TableGroup;
import org.eclipse.birt.report.model.elements.TableItem;
import org.eclipse.birt.report.model.elements.TemplateReportItem;
import org.eclipse.birt.report.model.elements.TextDataItem;
import org.eclipse.birt.report.model.elements.TextItem;
import org.eclipse.birt.report.model.elements.interfaces.IDataItemModel;
import org.eclipse.birt.report.model.elements.interfaces.IGroupElementModel;
import org.eclipse.birt.report.model.elements.interfaces.IListingElementModel;
import org.eclipse.birt.report.model.elements.interfaces.IReportItemModel;
import org.eclipse.birt.report.model.util.BoundColumnsMgr;
import org.eclipse.birt.report.model.util.BoundDataColumnUtil;
import org.eclipse.birt.report.model.util.LevelContentIterator;

/**
 * The utility to provide backward compatibility of bound columns during writing
 * the design file.
 */

final class BoundColumnsWriterMgr extends BoundColumnsMgr
{

	/**
	 * Elements on which bound columns have been created.
	 */

	private Set<DesignElement> processedElement = new HashSet<DesignElement>( );

	/**
	 * 
	 */

	private Map<GroupElement, List<Object>> cachedGroup = new HashMap<GroupElement, List<Object>>( );

	/**
	 * The design file version from parsing.
	 */

	private String version = null;

	/**
	 * Constructs a writer manager with the given design version.
	 * 
	 * @param version
	 *            the design version
	 */

	protected BoundColumnsWriterMgr( String version )
	{
		super( );
		this.version = version;
	}

	/**
	 * Creates bound columns for the given element.
	 * 
	 * @param element
	 *            the element
	 * @param module
	 *            the root of the element
	 * @param propValue
	 *            the value from which to create bound columns
	 */

	protected void handleBoundsForValue( DesignElement element, Module module,
			String propValue )
	{
		if ( propValue == null )
			return;

		List newExprs = null;

		try
		{
			newExprs = ExpressionUtil.extractColumnExpressions( propValue );
		}
		catch ( BirtException e )
		{
			// do nothing
		}

		if ( newExprs == null || newExprs.isEmpty( ) )
			return;

		DesignElement target = BoundDataColumnUtil.findTargetOfBoundColumns(
				element, module );

		if ( target instanceof GroupElement )
		{
			appendBoundColumnsToGroup( (GroupElement) target, newExprs );
			return;
		}

		if ( newExprs != null && newExprs.size( ) >= 1 )
		{
			for ( int i = 0; i < newExprs.size( ); i++ )
			{
				IColumnBinding boundColumn = (IColumnBinding) newExprs.get( i );
				String newExpression = boundColumn.getBoundExpression( );
				if ( newExpression == null )
					continue;

				BoundDataColumnUtil.createBoundDataColumn( target, boundColumn
						.getResultSetColumnName( ), newExpression, module );
			}
		}
	}

	/**
	 * Appends to the cached group bound columns. Becuase of "aggregateOn"
	 * property on bound columns, has to add bound columns at end() function of
	 * ListingElementState.
	 * 
	 * @param target
	 *            the group element
	 * @param newExprs
	 *            bound columns returned by ExpressionUtil
	 */

	private void appendBoundColumnsToGroup( GroupElement target, List newExprs )
	{
		List newColumns = new ArrayList( );
		for ( int i = 0; i < newExprs.size( ); i++ )
		{
			ComputedColumn column = StructureFactory.createComputedColumn( );
			IColumnBinding boundColumn = (IColumnBinding) newExprs.get( i );
			String newExpression = boundColumn.getBoundExpression( );
			if ( newExpression == null )
				continue;

			column.setName( boundColumn.getResultSetColumnName( ) );
			column.setExpression( boundColumn.getBoundExpression( ) );
			if ( !newColumns.contains( column ) )
				newColumns.add( column );
		}

		appendBoundColumnsToCachedGroup( target, newColumns );
	}

	/**
	 * Appends to the cached group bound columns. Becuase of "aggregateOn"
	 * property on bound columns, has to add bound columns at end() function of
	 * ListingElementState.
	 * 
	 * @param target
	 *            the group element
	 * @param newExprs
	 *            bound columns returned by ExpressionUtil
	 */

	private void appendBoundColumnsToCachedGroup( GroupElement target,
			List newColumns )
	{
		List<Object> boundColumns = cachedGroup.get( target );
		if ( boundColumns == null )
		{
			cachedGroup.put( target, newColumns );
			return;
		}

		for ( int i = 0; i < newColumns.size( ); i++ )
		{
			ComputedColumn column = (ComputedColumn) newColumns.get( i );
			if ( !boundColumns.contains( column ) )
				boundColumns.add( column );
		}
	}

	/**
	 * Appends to the cached group bound columns. Becuase of "aggregateOn"
	 * property on bound columns, has to add bound columns at end() function of
	 * ListingElementState.
	 * 
	 * @param target
	 *            the group element
	 * @param boundName
	 *            the bound column name
	 * @param expression
	 *            the bound column expression
	 * @return the return bound name
	 */

	protected String appendBoundColumnsToCachedGroup( GroupElement target,
			String boundName, String expression )
	{
		ComputedColumn column = StructureFactory.createComputedColumn( );
		column.setName( boundName );
		column.setExpression( expression );

		List<Object> boundColumns = cachedGroup.get( target );
		if ( boundColumns == null )
		{
			List newColumns = new ArrayList( );
			newColumns.add( column );

			cachedGroup.put( target, newColumns );
			return boundName;
		}

		boundColumns.add( column );

		return boundName;
	}

	/**
	 * Creates bound columns for the given value of the given element.
	 * 
	 * @param element
	 *            the element
	 * @param module
	 *            the root of the element
	 * @param propValue
	 *            the value from which to create bound columns
	 */

	protected void handleBoundsForParamBinding( DesignElement element,
			Module module, String propValue )
	{
		if ( propValue == null )
			return;

		List newExprs = null;

		try
		{
			newExprs = ExpressionUtil.extractColumnExpressions( propValue );
		}
		catch ( BirtException e )
		{
			// do nothing
		}

		if ( newExprs != null && newExprs.size( ) >= 1 )
		{
			DesignElement target = BoundDataColumnUtil
					.findTargetElementOfParamBinding( element, module );

			for ( int i = 0; i < newExprs.size( ); i++ )
			{
				IColumnBinding boundColumn = (IColumnBinding) newExprs.get( i );
				String newExpression = boundColumn.getBoundExpression( );
				if ( newExpression == null )
					continue;

				BoundDataColumnUtil.createBoundDataColumn( target, boundColumn
						.getResultSetColumnName( ), newExpression, module );
			}
		}
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.eclipse.birt.report.model.util.BoundColumnsMgr#dealData(org.eclipse
	 * .birt.report.model.elements.DataItem,
	 * org.eclipse.birt.report.model.core.Module)
	 */
	protected void dealData( DataItem element, Module module )
	{
		if ( version != null || processedElement.contains( element ) )
			return;

		processedElement.add( element );

		super.dealData( element, module );
		dealCompatibleValueExpr( element, module );
	}

	/**
	 * Converts the old value expression to the new result set column with
	 * correspoding bound columns.
	 * 
	 * @param obj
	 *            the data item
	 */

	private void dealCompatibleValueExpr( DataItem obj, Module module )
	{

		String valueExpr = (String) obj.getLocalProperty( module,
				IDataItemModel.RESULT_SET_COLUMN_PROP );
		if ( valueExpr == null )
			return;

		List newExprs = null;

		try
		{
			newExprs = ExpressionUtil.extractColumnExpressions( valueExpr );
		}
		catch ( BirtException e )
		{
			// do nothing
		}

		if ( newExprs == null || newExprs.size( ) == 0 )
			return;

		DesignElement target = BoundDataColumnUtil.findTargetOfBoundColumns(
				obj, module );

		if ( newExprs != null && newExprs.size( ) == 1 )
		{
			IColumnBinding column = (IColumnBinding) newExprs.get( 0 );

			String newName = column.getResultSetColumnName( );
			if ( target instanceof GroupElement )
			{
				appendBoundColumnsToCachedGroup( (GroupElement) target,
						newName, column.getBoundExpression( ) );
			}
			else
			{
				newName = BoundDataColumnUtil.createBoundDataColumn( target,
						newName, column.getBoundExpression( ), module );
			}

			if ( valueExpr.equals( ExpressionUtil.createRowExpression( column
					.getResultSetColumnName( ) ) ) )
			{
				// set the property for the result set column property of
				// DataItem.

				obj.setProperty( IDataItemModel.RESULT_SET_COLUMN_PROP, newName );

				return;
			}
		}

		if ( newExprs != null && newExprs.size( ) > 1 )
		{
			if ( target instanceof GroupElement )
			{
				appendBoundColumnsToCachedGroup( (GroupElement) target,
						newExprs );
			}
			else
			{
				for ( int i = 0; i < newExprs.size( ); i++ )
				{
					IColumnBinding boundColumn = (IColumnBinding) newExprs
							.get( i );
					String newExpression = boundColumn.getBoundExpression( );
					if ( newExpression == null )
						continue;

					BoundDataColumnUtil.createBoundDataColumn( target,
							boundColumn.getResultSetColumnName( ),
							newExpression, module );
				}
			}
		}

		String newName = valueExpr;
		if ( target instanceof GroupElement )
		{
			appendBoundColumnsToCachedGroup( (GroupElement) target, valueExpr,
					valueExpr );
		}
		else
		{
			newName = BoundDataColumnUtil.createBoundDataColumn( target,
					valueExpr, valueExpr, module );
		}

		// set the property for the result set column property of DataItem.

		obj.setProperty( IDataItemModel.RESULT_SET_COLUMN_PROP, newName );
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.eclipse.birt.report.model.util.BoundColumnsMgr#dealExtendedItem(org
	 * .eclipse.birt.report.model.elements.ExtendedItem,
	 * org.eclipse.birt.report.model.core.Module)
	 */
	protected void dealExtendedItem( ExtendedItem element, Module module )
	{
		if ( version != null || processedElement.contains( element ) )
			return;

		processedElement.add( element );

		super.dealExtendedItem( element, module );
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.eclipse.birt.report.model.util.BoundColumnsMgr#dealGrid(org.eclipse
	 * .birt.report.model.elements.GridItem,
	 * org.eclipse.birt.report.model.core.Module)
	 */
	protected void dealGrid( GridItem element, Module module )
	{
		if ( version != null || processedElement.contains( element ) )
			return;

		processedElement.add( element );

		super.dealGrid( element, module );
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.eclipse.birt.report.model.util.BoundColumnsMgr#dealImage(org.eclipse
	 * .birt.report.model.elements.ImageItem,
	 * org.eclipse.birt.report.model.core.Module)
	 */
	protected void dealImage( ImageItem element, Module module )
	{
		if ( version != null || processedElement.contains( element ) )
			return;

		processedElement.add( element );

		super.dealImage( element, module );
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.eclipse.birt.report.model.util.BoundColumnsMgr#dealLabel(org.eclipse
	 * .birt.report.model.elements.Label,
	 * org.eclipse.birt.report.model.core.Module)
	 */
	protected void dealLabel( Label element, Module module )
	{
		if ( version != null || processedElement.contains( element ) )
			return;

		processedElement.add( element );

		super.dealLabel( element, module );
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.eclipse.birt.report.model.util.BoundColumnsMgr#dealList(org.eclipse
	 * .birt.report.model.elements.ListItem,
	 * org.eclipse.birt.report.model.core.Module)
	 */
	protected void dealList( ListItem element, Module module )
	{
		if ( version != null || processedElement.contains( element ) )
			return;

		processedElement.add( element );

		super.dealList( element, module );

		appendCachedBoundColumns( element, module );
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.eclipse.birt.report.model.util.BoundColumnsMgr#dealScalarParameter
	 * (org.eclipse.birt.report.model.elements.ScalarParameter,
	 * org.eclipse.birt.report.model.core.Module)
	 */
	protected void dealScalarParameter( ScalarParameter element, Module module )
	{
		if ( version != null || processedElement.contains( element ) )
			return;

		processedElement.add( element );

		super.dealScalarParameter( element, module );
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.eclipse.birt.report.model.util.BoundColumnsMgr#dealTable(org.eclipse
	 * .birt.report.model.elements.TableItem,
	 * org.eclipse.birt.report.model.core.Module)
	 */
	protected void dealTable( TableItem element, Module module )
	{
		if ( version != null || processedElement.contains( element ) )
			return;

		processedElement.add( element );

		super.dealTable( element, module );

		appendCachedBoundColumns( element, module );
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.eclipse.birt.report.model.util.BoundColumnsMgr#dealTemplateReportItem
	 * (org.eclipse.birt.report.model.elements.TemplateReportItem,
	 * org.eclipse.birt.report.model.core.Module)
	 */
	protected void dealTemplateReportItem( TemplateReportItem element,
			Module module )
	{
		if ( version != null || processedElement.contains( element ) )
			return;

		processedElement.add( element );

		super.dealTemplateReportItem( element, module );
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.eclipse.birt.report.model.util.BoundColumnsMgr#dealText(org.eclipse
	 * .birt.report.model.elements.TextItem,
	 * org.eclipse.birt.report.model.core.Module)
	 */
	protected void dealText( TextItem element, Module module )
	{
		if ( version != null || processedElement.contains( element ) )
			return;

		processedElement.add( element );

		super.dealText( element, module );
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.eclipse.birt.report.model.util.BoundColumnsMgr#dealTextData(org.eclipse
	 * .birt.report.model.elements.TextDataItem,
	 * org.eclipse.birt.report.model.core.Module)
	 */
	protected void dealTextData( TextDataItem element, Module module )
	{
		if ( version != null || processedElement.contains( element ) )
			return;

		processedElement.add( element );

		super.dealTextData( element, module );
	}

	/**
	 * Returns the bound column of which expression and aggregateOn values are
	 * equals to the input column.
	 * 
	 * @param columns
	 *            the bound column list
	 * @param column
	 *            the input bound column
	 * @return the matched bound column
	 */

	private ComputedColumn checkMatchedBoundColumnForGroup( List columns,
			String expression, String aggregateOn )
	{
		if ( ( columns == null ) || ( columns.size( ) == 0 )
				|| expression == null )
			return null;

		for ( int i = 0; i < columns.size( ); i++ )
		{
			ComputedColumn column = (ComputedColumn) columns.get( i );
			if ( expression.equals( column.getExpression( ) ) )
			{
				if ( aggregateOn == null && column.getAggregateOn( ) == null )
					return column;

				if ( aggregateOn != null
						&& aggregateOn.equals( column.getAggregateOn( ) ) )
					return column;
			}
		}

		return null;
	}

	/**
	 * Creates a unique bound column name in the column bound list.
	 * 
	 * @param columns
	 *            the bound column list
	 * @param checkColumn
	 *            the column of which name to check
	 * @return the newly created column name
	 */

	private String getUniqueBoundColumnNameForGroup( List columns,
			ComputedColumn checkColumn )
	{
		String oldName = checkColumn.getName( );
		String tmpName = oldName;
		int index = 0;

		while ( true )
		{
			ComputedColumn column = DataColumnNameValidator.getColumn( columns,
					tmpName );
			if ( column == null )
				break;

			tmpName = oldName + "_" + ++index; //$NON-NLS-1$
		}

		return tmpName;
	}

	/**
	 * Reset the result column name for the data item. Since the bound column
	 * name may recreated in this state, the corresponding result set colum must
	 * be resetted.
	 * 
	 * @param group
	 *            the group element
	 * @param columns
	 *            the bound column list
	 */

	private void reCheckResultSetColumnName( GroupElement group, List columns,
			Module module )
	{
		int level = -1;
		if ( group instanceof TableGroup )
			level = 3;
		if ( group instanceof ListGroup )
			level = 1;

		LevelContentIterator contentIter = new LevelContentIterator( module,
				group, level );
		while ( contentIter.hasNext( ) )
		{
			DesignElement item = contentIter.next( );
			if ( !( item instanceof DataItem ) )
				continue;

			String resultSetColumn = (String) item.getLocalProperty( module,
					IDataItemModel.RESULT_SET_COLUMN_PROP );

			if ( StringUtil.isBlank( resultSetColumn ) )
				continue;

			ComputedColumn foundColumn = DataColumnNameValidator.getColumn(
					columns, resultSetColumn );

			if ( foundColumn == null )
				continue;

			foundColumn = checkMatchedBoundColumnForGroup( columns, foundColumn
					.getExpression( ), (String) group.getLocalProperty( module,
					IGroupElementModel.GROUP_NAME_PROP ) );

			if ( foundColumn == null )
				continue;

			item.setProperty( IDataItemModel.RESULT_SET_COLUMN_PROP,
					foundColumn.getName( ) );
		}
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.report.model.parser.ReportItemState#end()
	 */

	private void appendCachedBoundColumns( ListingElement element, Module module )
	{

		Set<GroupElement> elements = cachedGroup.keySet( );
		ContainerSlot groups = element
				.getSlot( IListingElementModel.GROUP_SLOT );
		for ( int i = 0; i < groups.getCount( ); i++ )
		{
			GroupElement group = (GroupElement) groups.getContent( i );

			module.getNameHelper( ).makeUniqueName( group );

			String groupName = (String) group.getLocalProperty( module,
					IGroupElementModel.GROUP_NAME_PROP );

			if ( !elements.contains( group ) )
				continue;

			List<Object> columns = cachedGroup.get( group );
			if ( columns == null || columns.isEmpty( ) )
				continue;

			List tmpList = (List) element.getLocalProperty( module,
					IReportItemModel.BOUND_DATA_COLUMNS_PROP );

			if ( tmpList == null )
			{
				tmpList = new ArrayList( );
				element.setProperty( IReportItemModel.BOUND_DATA_COLUMNS_PROP,
						tmpList );
			}

			for ( int j = 0; j < columns.size( ); j++ )
			{
				ComputedColumn column = (ComputedColumn) columns.get( j );

				column.setAggregateOn( groupName );

				ComputedColumn foundColumn = checkMatchedBoundColumnForGroup(
						tmpList, column.getExpression( ), column
								.getAggregateOn( ) );
				if ( foundColumn == null
						|| !foundColumn.getName( ).equals( column.getName( ) ) )
				{
					String newName = getUniqueBoundColumnNameForGroup( tmpList,
							column );
					column.setName( newName );
					tmpList.add( column );
				}
			}

			reCheckResultSetColumnName( group, tmpList, module );
		}

	}
}
