/*
 *  Licensed to the Apache Software Foundation (ASF) under one
 *  or more contributor license agreements.  See the NOTICE file
 *  distributed with this work for additional information
 *  regarding copyright ownership.  The ASF licenses this file
 *  to you 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.
 */
package org.codehaus.groovy.transform.tailrec

import groovy.transform.CompileStatic
import org.codehaus.groovy.ast.CodeVisitorSupport
import org.codehaus.groovy.ast.MethodNode
import org.codehaus.groovy.ast.expr.Expression
import org.codehaus.groovy.ast.expr.MethodCallExpression
import org.codehaus.groovy.ast.expr.StaticMethodCallExpression

/**
 * Collect all recursive calls within method
 */
@CompileStatic
class CollectRecursiveCalls extends CodeVisitorSupport {
	MethodNode method
	List<Expression> recursiveCalls = []

	void visitMethodCallExpression(MethodCallExpression call) {
		if (isRecursive(call)) {
			recursiveCalls << call
		}
        super.visitMethodCallExpression(call)
    }

	void visitStaticMethodCallExpression(StaticMethodCallExpression call) {
		if (isRecursive(call)) {
            recursiveCalls << call
        }
		super.visitStaticMethodCallExpression(call)
	}
	
	private boolean isRecursive(call) {
		new RecursivenessTester().isRecursive(method: method, call: call)
	}
	
	synchronized List<Expression> collect(MethodNode method) {
		recursiveCalls.clear()
		this.method = method
		this.method.code.visit(this)
		recursiveCalls
	}
}
