/*
 * 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.apache.tuscany.sca.implementation.java.introspect.impl;

import java.lang.reflect.Field;
import java.lang.reflect.Method;

import org.apache.tuscany.sca.assembly.AssemblyFactory;
import org.apache.tuscany.sca.implementation.java.IntrospectionException;
import org.apache.tuscany.sca.implementation.java.JavaImplementation;
import org.apache.tuscany.sca.implementation.java.introspect.BaseJavaClassVisitor;
import org.oasisopen.sca.annotation.ConversationAttributes;
import org.oasisopen.sca.annotation.ConversationID;
import org.oasisopen.sca.annotation.Scope;

/**
 * @version $Rev$ $Date$
 */
public class ConversationProcessor extends BaseJavaClassVisitor {
    private static final String SECONDS = " SECONDS";
    private static final String MINUTES = " MINUTES";
    private static final String HOURS = " HOURS";
    private static final String DAYS = " DAYS";
    private static final String YEARS = " YEARS";
    
    public ConversationProcessor(AssemblyFactory factory) {
        super(factory);
    }

    @Override
    public <T> void visitClass(Class<T> clazz, JavaImplementation type) throws IntrospectionException {

        ConversationAttributes conversation = clazz.getAnnotation(ConversationAttributes.class);
        if (conversation == null) {
            return;
        }
        Scope scope = clazz.getAnnotation(Scope.class);
        if (scope == null) {
            // implicitly assume conversation
            type.setJavaScope(org.apache.tuscany.sca.implementation.java.JavaScopeImpl.CONVERSATION);
        } else if (conversation != null) {
            long maxAge;
            long maxIdleTime;
            String maxAgeVal = conversation.maxAge();
            String maxIdleTimeVal = conversation.maxIdleTime();
            try {
                if (maxAgeVal.length() > 0) {
                    maxAge = convertTimeMillis(maxAgeVal);
                    type.setMaxAge(maxAge);
                }
            } catch (NumberFormatException e) {
                throw new InvalidConversationalImplementationException("Invalid maximum age", e);
            }
            try {
                if (maxIdleTimeVal.length() > 0) {
                    maxIdleTime = convertTimeMillis(maxIdleTimeVal);
                    type.setMaxIdleTime(maxIdleTime);
                }
            } catch (NumberFormatException e) {
                throw new InvalidConversationalImplementationException("Invalid maximum idle time", e);
            }
        }

    }

    @Override
    public void visitMethod(Method method,
                            JavaImplementation type) throws IntrospectionException {
        ConversationID conversationID = method.getAnnotation(ConversationID.class);
        if (conversationID == null) {
            return;
        }
        type.addConversationIDMember(method);
    }

    @Override
    public void visitField(Field field,
                           JavaImplementation type) throws IntrospectionException {
        ConversationID conversationID = field.getAnnotation(ConversationID.class);
        if (conversationID == null) {
            return;
        }
        type.addConversationIDMember(field);
    }

    static long convertTimeMillis(String expr) throws NumberFormatException {
        expr = expr.trim().toUpperCase();
        int i = expr.lastIndexOf(SECONDS);
        if (i >= 0) {
            String units = expr.substring(0, i);
            return Long.parseLong(units) * 1000;
        }
        i = expr.lastIndexOf(MINUTES);
        if (i >= 0) {
            String units = expr.substring(0, i);
            return Long.parseLong(units) * 60000;
        }

        i = expr.lastIndexOf(HOURS);
        if (i >= 0) {
            String units = expr.substring(0, i);
            return Long.parseLong(units) * 3600000;
        }
        i = expr.lastIndexOf(DAYS);
        if (i >= 0) {
            String units = expr.substring(0, i);
            return Long.parseLong(units) * 86400000;
        }
        i = expr.lastIndexOf(YEARS);
        if (i >= 0) {
            String units = expr.substring(0, i);
            return Long.parseLong(units) * 31556926000L;
        }
        return Long.parseLong(expr) * 1000; // assume seconds if no suffix
                                            // specified
    }
}