/*******************************************************************************
 * Copyright (c) 2000, 2004 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials 
 * are made available under the terms of the Common Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/cpl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.wst.jsdt.internal.compiler.lookup;

import java.util.Map;
import org.eclipse.wst.jsdt.core.compiler.CharOperation;
import org.eclipse.wst.jsdt.internal.compiler.impl.Constant;

public final class ArrayBinding extends TypeBinding {
	// creation and initialization of the length field
	// the declaringClass of this field is intentionally set to null so it can be distinguished.
	public static final FieldBinding ArrayLength = new FieldBinding(LENGTH, IntBinding, AccPublic | AccFinal, null, Constant.NotAConstant);

	public TypeBinding leafComponentType;
	public int dimensions;
	LookupEnvironment environment;	
	char[] constantPoolName;
	char[] genericTypeSignature;
	
public ArrayBinding(TypeBinding type, int dimensions, LookupEnvironment environment) {
	this.tagBits |= IsArrayType;
	this.leafComponentType = type;
	this.dimensions = dimensions;
	this.environment = environment;
	if (type instanceof UnresolvedReferenceBinding)
		((UnresolvedReferenceBinding) type).addWrapper(this);
	else
    	this.tagBits |= type.tagBits & (HasTypeVariable | HasWildcard);
}

/**
 * Collect the substitutes into a map for certain type variables inside the receiver type
 * e.g.   Collection<T>.findSubstitute(T, Collection<List<X>>):   T --> List<X>
 */
public void collectSubstitutes(TypeBinding otherType, Map substitutes) {
    if (otherType.isArrayType()) {
        int otherDim = otherType.dimensions();
        if (otherDim == this.dimensions) {
		    this.leafComponentType.collectSubstitutes(otherType.leafComponentType(), substitutes);
        } else if (otherDim > this.dimensions) {
            ArrayBinding otherReducedType = this.environment.createArrayType(otherType.leafComponentType(), otherDim - this.dimensions);
            this.leafComponentType.collectSubstitutes(otherReducedType, substitutes);
        }
    } 
}
	
/**
 * Answer the receiver's constant pool name.
 * NOTE: This method should only be used during/after code gen.
 * e.g. '[Ljava/lang/Object;'
 */
public char[] constantPoolName() {
	if (constantPoolName != null)
		return constantPoolName;

	char[] brackets = new char[dimensions];
	for (int i = dimensions - 1; i >= 0; i--) brackets[i] = '[';
	return constantPoolName = CharOperation.concat(brackets, leafComponentType.signature());
}
public String debugName() {
	StringBuffer brackets = new StringBuffer(dimensions * 2);
	for (int i = dimensions; --i >= 0;)
		brackets.append("[]"); //$NON-NLS-1$
	return leafComponentType.debugName() + brackets.toString();
}
public int dimensions() {
	return this.dimensions;
}

/* Answer an array whose dimension size is one less than the receiver.
*
* When the receiver's dimension size is one then answer the leaf component type.
*/

public TypeBinding elementsType() {
	if (this.dimensions == 1) return this.leafComponentType;
	return this.environment.createArrayType(this.leafComponentType, this.dimensions - 1);
}
/**
 * @see org.eclipse.wst.jsdt.internal.compiler.lookup.TypeBinding#erasure()
 */
public TypeBinding erasure() {
    TypeBinding erasedType = this.leafComponentType.erasure();
    if (this.leafComponentType != erasedType)
        return this.environment.createArrayType(erasedType, this.dimensions);
    return this;
}
public LookupEnvironment environment() {
    return this.environment;
}

public char[] genericTypeSignature() {
	
    if (this.genericTypeSignature == null) {
		char[] brackets = new char[dimensions];
		for (int i = dimensions - 1; i >= 0; i--) brackets[i] = '[';
		this.genericTypeSignature = CharOperation.concat(brackets, leafComponentType.genericTypeSignature());
    }
    return this.genericTypeSignature;
}

public PackageBinding getPackage() {
	return leafComponentType.getPackage();
}
public int hashCode() {
	return this.leafComponentType == null ? super.hashCode() : this.leafComponentType.hashCode();
}
/* Answer true if the receiver type can be assigned to the argument type (right)
*/
public boolean isCompatibleWith(TypeBinding right) {
	if (this == right)
		return true;

	if (right.isArrayType()) {
		ArrayBinding rightArray = (ArrayBinding) right;
		if (rightArray.leafComponentType.isBaseType())
			return false; // relying on the fact that all equal arrays are identical
		if (dimensions == rightArray.dimensions)
			return leafComponentType.isCompatibleWith(rightArray.leafComponentType);
		if (dimensions < rightArray.dimensions)
			return false; // cannot assign 'String[]' into 'Object[][]' but can assign 'byte[][]' into 'Object[]'
	} else {
		if (right.isBaseType())
			return false;
		if (right.isWildcard()) {
		    return ((WildcardBinding) right).boundCheck(this);
		}
	}
	//Check dimensions - Java does not support explicitly sized dimensions for types.
	//However, if it did, the type checking support would go here.
	switch (right.leafComponentType().id) {
	    case T_JavaLangObject :
	    case T_JavaLangCloneable :
	    case T_JavaIoSerializable :
	        return true;
	}
	return false;
}

/**
 * Returns true if a type is identical to another one,
 * or for generic types, true if compared to its raw type.
 */
public boolean isEquivalentTo(TypeBinding otherType) {
    if (this == otherType) return true;
    if (otherType == null) return false;
    if (otherType.isWildcard()) // wildcard
		return ((WildcardBinding) otherType).boundCheck(this);
	return false;

}
public TypeBinding leafComponentType(){
	return leafComponentType;
}

/* API
* Answer the problem id associated with the receiver.
* NoError if the receiver is a valid binding.
*/

public int problemId() {
	return leafComponentType.problemId();
}
/**
* Answer the source name for the type.
* In the case of member types, as the qualified name from its top level type.
* For example, for a member type N defined inside M & A: "A.M.N".
*/

public char[] qualifiedSourceName() {
	char[] brackets = new char[dimensions * 2];
	for (int i = dimensions * 2 - 1; i >= 0; i -= 2) {
		brackets[i] = ']';
		brackets[i - 1] = '[';
	}
	return CharOperation.concat(leafComponentType.qualifiedSourceName(), brackets);
}
public char[] readableName() /* java.lang.Object[] */ {
	char[] brackets = new char[dimensions * 2];
	for (int i = dimensions * 2 - 1; i >= 0; i -= 2) {
		brackets[i] = ']';
		brackets[i - 1] = '[';
	}
	return CharOperation.concat(leafComponentType.readableName(), brackets);
}
public char[] shortReadableName(){
	char[] brackets = new char[dimensions * 2];
	for (int i = dimensions * 2 - 1; i >= 0; i -= 2) {
		brackets[i] = ']';
		brackets[i - 1] = '[';
	}
	return CharOperation.concat(leafComponentType.shortReadableName(), brackets);
}
public char[] sourceName() {
	char[] brackets = new char[dimensions * 2];
	for (int i = dimensions * 2 - 1; i >= 0; i -= 2) {
		brackets[i] = ']';
		brackets[i - 1] = '[';
	}
	return CharOperation.concat(leafComponentType.sourceName(), brackets);
}
public void swapUnresolved(UnresolvedReferenceBinding unresolvedType, ReferenceBinding resolvedType, LookupEnvironment env) {
	if (this.leafComponentType == unresolvedType) {
		this.leafComponentType = resolvedType.isGenericType() ? env.createRawType(resolvedType, null) : resolvedType;
		this.tagBits |= this.leafComponentType.tagBits & (HasTypeVariable | HasWildcard);
	}
}
public String toString() {
	return leafComponentType != null ? debugName() : "NULL TYPE ARRAY"; //$NON-NLS-1$
}
}
