/*******************************************************************************
 *  Copyright (c) 2010 Association for Decentralized Information Management in
 *  Industry THTH ry.
 *  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:
 *      VTT Technical Research Centre of Finland - initial API and implementation
 *******************************************************************************/
package org.simantics.databoard.parser.unparsing;

import gnu.trove.set.hash.THashSet;

import java.util.ArrayList;
import java.util.List;

import org.simantics.databoard.parser.ast.type.AstArrayType;
import org.simantics.databoard.parser.ast.type.AstComponent;
import org.simantics.databoard.parser.ast.type.AstRecordType;
import org.simantics.databoard.parser.ast.type.AstTupleType;
import org.simantics.databoard.parser.ast.type.AstType;
import org.simantics.databoard.parser.ast.type.AstTypeDefinition;
import org.simantics.databoard.parser.ast.type.AstTypeReference;
import org.simantics.databoard.parser.ast.type.AstUnionType;
import org.simantics.databoard.parser.repository.DataTypeRepository;
import org.simantics.databoard.type.ArrayType;
import org.simantics.databoard.type.BooleanType;
import org.simantics.databoard.type.ByteType;
import org.simantics.databoard.type.Component;
import org.simantics.databoard.type.Datatype;
import org.simantics.databoard.type.Datatype.Visitor;
import org.simantics.databoard.type.DoubleType;
import org.simantics.databoard.type.FloatType;
import org.simantics.databoard.type.IntegerType;
import org.simantics.databoard.type.LongType;
import org.simantics.databoard.type.MapType;
import org.simantics.databoard.type.NumberType;
import org.simantics.databoard.type.OptionalType;
import org.simantics.databoard.type.RecordType;
import org.simantics.databoard.type.StringType;
import org.simantics.databoard.type.UnionType;
import org.simantics.databoard.type.VariantType;

/**
 * Converts data type to abstract syntax tree.
 * 
 * @author Hannu Niemistö
 */
public class DataTypeToAst implements Visitor<AstType> {

	List<AstTypeDefinition> typeDefinitions = new ArrayList<AstTypeDefinition>();
	DataTypeRepository repo = new DataTypeRepository();
	THashSet<Datatype> underConstruction = new THashSet<Datatype>();

	int id = 0;

	public DataTypeToAst(DataTypeRepository repo) {
		this.repo = repo;
	}
	
	private String freshTypeName() {
		return "Temp" + (++id);
	}
	
	public AstType addDefinition(String name, Datatype type) {
		repo.add(name, type);
		AstType ast = type.accept(this);		
		typeDefinitions.add(new AstTypeDefinition(name, type.accept(this)));
		return ast;
	}
	
	public AstType visit(Datatype type) {
		if(repo.contains(type))
			return new AstTypeReference(repo.get(type));
		if(underConstruction.contains(type)) {
			String name = repo.get(type);
			if (name==null) {
				name = freshTypeName();
				repo.add(name, type);
			}
			underConstruction.remove(type);
			return new AstTypeReference(name);
		}
		else {
			underConstruction.add(type);
			AstType ast = type.accept(this);
			if(!underConstruction.remove(type)) {
				String name = repo.get(type);
				typeDefinitions.add(new AstTypeDefinition(name, ast));
				return new AstTypeReference(name);
			}
			else
				return ast;
		}
	}
	
	@Override
	public AstType visit(ArrayType b) {
		return new AstArrayType(visit(b.componentType), 
				b.getLength()==null ? null : b.getLength().getLower().smallestIncludedInteger(),
			    b.getLength()==null ? null : b.getLength().getUpper().greatestIncludedInteger());
	}

	@Override
	public AstType visit(BooleanType b) {
		return new AstTypeReference("Boolean");
	}

	@Override
	public AstType visit(DoubleType b) {
		AstTypeReference ref = new AstTypeReference("Double");
		// XXX
		if( b.metadata.containsKey( NumberType.KEY_RANGE ) )
			ref.addAttribute("range", b.metadata.get( NumberType.KEY_RANGE ) );		
		if( b.metadata.containsKey( NumberType.KEY_UNIT ) )
			ref.addAttribute("unit", b.metadata.get( NumberType.KEY_UNIT ));
		return ref;
	}

	@Override
	public AstType visit(FloatType b) {
		AstTypeReference ref = new AstTypeReference("Float");
		// XXX
		if( b.metadata.containsKey( NumberType.KEY_RANGE ) )
			ref.addAttribute("range", b.metadata.get( NumberType.KEY_RANGE ) );		
		if( b.metadata.containsKey( NumberType.KEY_UNIT ) )
			ref.addAttribute("unit", b.metadata.get( NumberType.KEY_UNIT ));
		return ref;
	}

	@Override
	public AstType visit(IntegerType b) {
		AstTypeReference ref = new AstTypeReference("Integer");
		// XXX
		if( b.metadata.containsKey( NumberType.KEY_RANGE ) )
			ref.addAttribute("range", b.metadata.get( NumberType.KEY_RANGE ) );		
		if( b.metadata.containsKey( NumberType.KEY_UNIT ) )
			ref.addAttribute("unit", b.metadata.get( NumberType.KEY_UNIT ));
		return ref;
	}

	@Override
	public AstType visit(ByteType b) {
		return new AstTypeReference("Byte");
	}

	@Override
	public AstType visit(LongType b) {
		AstTypeReference ref = new AstTypeReference("Long");
		// XXX
		if( b.metadata.containsKey( NumberType.KEY_RANGE ) )
			ref.addAttribute("range", b.metadata.get( NumberType.KEY_RANGE ) );		
		if( b.metadata.containsKey( NumberType.KEY_UNIT ) )
			ref.addAttribute("unit", b.metadata.get( NumberType.KEY_UNIT ));
		return ref;
	}

	@Override
	public AstType visit(OptionalType b) {
		return new AstTypeReference("Optional", visit(b.getComponentType()));
	}

	@Override
	public AstType visit(RecordType b) {
		if(b.isTupleType()) {
			AstTupleType tuple = new AstTupleType(new ArrayList<AstType>(b.getComponentCount()));
			for(Component component : b.getComponents()) 
				tuple.addComponent(visit(component.type));
			return tuple;
		}
		else {
			AstRecordType record = new AstRecordType(b.isReferable(), new ArrayList<AstComponent>(b.getComponentCount()));
			for(Component component : b.getComponents()) 
				record.addComponent(component.name, visit(component.type));
			return record;
		}
	}

	@Override
	public AstType visit(StringType b) {
		AstTypeReference ref = new AstTypeReference("String");
		// XXX
		if( b.metadata.containsKey( StringType.KEY_MIMETYPE ) )
			ref.addAttribute("mimeType", b.metadata.get( StringType.KEY_MIMETYPE ));
		if( b.metadata.containsKey( StringType.KEY_LENGTH ) )
			ref.addAttribute("length", b.metadata.get( StringType.KEY_LENGTH ));
		if( b.metadata.containsKey( StringType.KEY_PATTERN ))
			ref.addAttribute("pattern", b.metadata.get( StringType.KEY_PATTERN ));
		return ref;
	}

	@Override
	public AstType visit(UnionType b) {
		AstUnionType union = new AstUnionType(new ArrayList<AstComponent>(b.components.length));
		for(Component component : b.components) 
			union.addComponent(component.name, visit(component.type));
		return union;
	}	
	
	@Override
	public AstType visit(VariantType b) {
		AstTypeReference ref = new AstTypeReference("Variant");
		return ref;
	}
	
	public List<AstTypeDefinition> getTypeDefinitions() {
		return typeDefinitions;
	}

	@Override
	public AstType visit(MapType b) {
		AstTypeReference ref = new AstTypeReference("Map", visit(b.keyType), visit(b.valueType));
		return ref;
	}
	
}