/*******************************************************************************
 * Copyright (c) 2000, 2003 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 net.sourceforge.phpdt.internal.compiler.flow;

import net.sourceforge.phpdt.internal.compiler.ast.ASTNode;
import net.sourceforge.phpdt.internal.compiler.ast.Reference;
import net.sourceforge.phpdt.internal.compiler.lookup.BlockScope;
import net.sourceforge.phpdt.internal.compiler.lookup.FieldBinding;
import net.sourceforge.phpdt.internal.compiler.lookup.LocalVariableBinding;
import net.sourceforge.phpdt.internal.compiler.lookup.VariableBinding;

/**
 * Reflects the context of code analysis, keeping track of enclosing try
 * statements, exception handlers, etc...
 */
public class FinallyFlowContext extends FlowContext {

	Reference finalAssignments[];

	VariableBinding finalVariables[];

	int assignCount;

	public FinallyFlowContext(FlowContext parent, ASTNode associatedNode) {
		super(parent, associatedNode);
	}

	/**
	 * Given some contextual initialization info (derived from a try block or a
	 * catch block), this code will check that the subroutine context does not
	 * also initialize a final variable potentially set redundantly.
	 */
	public void complainOnRedundantFinalAssignments(FlowInfo flowInfo,
			BlockScope scope) {
		for (int i = 0; i < assignCount; i++) {
			VariableBinding variable = finalVariables[i];
			if (variable == null)
				continue;

			boolean complained = false; // remember if have complained on this
										// final assignment
			if (variable instanceof FieldBinding) {
				// final field
				if (flowInfo.isPotentiallyAssigned((FieldBinding) variable)) {
					complained = true;
					scope.problemReporter()
							.duplicateInitializationOfBlankFinalField(
									(FieldBinding) variable,
									finalAssignments[i]);
				}
			} else {
				// final local variable
				if (flowInfo
						.isPotentiallyAssigned((LocalVariableBinding) variable)) {
					complained = true;
					scope.problemReporter()
							.duplicateInitializationOfFinalLocal(
									(LocalVariableBinding) variable,
									finalAssignments[i]);
				}
			}
			// any reference reported at this level is removed from the parent
			// context
			// where it could also be reported again
			if (complained) {
				FlowContext currentContext = parent;
				while (currentContext != null) {
					// if (currentContext.isSubRoutine()) {
					currentContext
							.removeFinalAssignmentIfAny(finalAssignments[i]);
					// }
					currentContext = currentContext.parent;
				}
			}
		}
	}

	public String individualToString() {

		StringBuffer buffer = new StringBuffer("Finally flow context"); //$NON-NLS-1$
		buffer
				.append("[finalAssignments count -").append(assignCount).append(']'); //$NON-NLS-1$
		return buffer.toString();
	}

	public boolean isSubRoutine() {
		return true;
	}

	boolean recordFinalAssignment(VariableBinding binding,
			Reference finalAssignment) {
		if (assignCount == 0) {
			finalAssignments = new Reference[5];
			finalVariables = new VariableBinding[5];
		} else {
			if (assignCount == finalAssignments.length)
				System.arraycopy(finalAssignments, 0,
						(finalAssignments = new Reference[assignCount * 2]), 0,
						assignCount);
			System.arraycopy(finalVariables, 0,
					(finalVariables = new VariableBinding[assignCount * 2]), 0,
					assignCount);
		}
		;
		finalAssignments[assignCount] = finalAssignment;
		finalVariables[assignCount++] = binding;
		return true;
	}

	void removeFinalAssignmentIfAny(Reference reference) {
		for (int i = 0; i < assignCount; i++) {
			if (finalAssignments[i] == reference) {
				finalAssignments[i] = null;
				finalVariables[i] = null;
				return;
			}
		}
	}
}
