/*
 * Copyright 2015 the original author or authors.
 *
 * Licensed 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.springframework.statemachine.state;

import static org.hamcrest.Matchers.contains;
import static org.junit.Assert.assertThat;
import static org.junit.Assert.assertTrue;

import java.util.EnumSet;

import org.junit.Test;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.context.annotation.Configuration;
import org.springframework.statemachine.AbstractStateMachineTests;
import org.springframework.statemachine.ObjectStateMachine;
import org.springframework.statemachine.StateMachineSystemConstants;
import org.springframework.statemachine.config.EnableStateMachine;
import org.springframework.statemachine.config.EnumStateMachineConfigurerAdapter;
import org.springframework.statemachine.config.builders.StateMachineStateConfigurer;
import org.springframework.statemachine.config.builders.StateMachineTransitionConfigurer;

/**
 * Tests for functionality around state machine initial state.
 *
 * @author Janne Valkealahti
 *
 */
public class InitialStateTests extends AbstractStateMachineTests {

	@SuppressWarnings({ "unchecked" })
	@Test
	public void testInitialStateTransition() throws Exception {
		context.register(BaseConfig.class, Config1.class);
		context.refresh();
		assertTrue(context.containsBean(StateMachineSystemConstants.DEFAULT_ID_STATEMACHINE));
		ObjectStateMachine<TestStates,TestEvents> machine =
				context.getBean(StateMachineSystemConstants.DEFAULT_ID_STATEMACHINE, ObjectStateMachine.class);
		machine.start();
		assertThat(machine.getState().getIds(), contains(TestStates.S1));
	}

	@Test(expected = Exception.class)
	public void testInitialStateMissingFailure() throws Exception {
		context.register(BaseConfig.class, Config2.class);
		context.refresh();
	}

	@SuppressWarnings({ "unchecked" })
	@Test
	public void testInitialNoNeedAsState() throws Exception {
		context.register(BaseConfig.class, Config3.class);
		context.refresh();
		assertTrue(context.containsBean(StateMachineSystemConstants.DEFAULT_ID_STATEMACHINE));
		ObjectStateMachine<TestStates,TestEvents> machine =
				context.getBean(StateMachineSystemConstants.DEFAULT_ID_STATEMACHINE, ObjectStateMachine.class);
		machine.start();
		assertThat(machine.getState().getIds(), contains(TestStates.SI));
		machine.sendEvent(TestEvents.E1);
		assertThat(machine.getState().getIds(), contains(TestStates.S1));
	}

	@Configuration
	@EnableStateMachine
	public static class Config1 extends EnumStateMachineConfigurerAdapter<TestStates, TestEvents> {

		@Override
		public void configure(StateMachineStateConfigurer<TestStates, TestEvents> states) throws Exception {
			states
				.withStates()
					.initial(TestStates.SI)
					.states(EnumSet.allOf(TestStates.class));
		}

		@Override
		public void configure(StateMachineTransitionConfigurer<TestStates, TestEvents> transitions) throws Exception {
			transitions
				.withExternal()
					.source(TestStates.SI)
					.target(TestStates.S1)
					.and()
				.withExternal()
					.source(TestStates.S1)
					.target(TestStates.S2)
					.event(TestEvents.E1)
					.and()
				.withExternal()
					.source(TestStates.S2)
					.target(TestStates.S3)
					.event(TestEvents.E2);
		}

	}

	@Configuration
	@EnableStateMachine
	public static class Config2 extends EnumStateMachineConfigurerAdapter<TestStates, TestEvents> {

		@Override
		public void configure(StateMachineStateConfigurer<TestStates, TestEvents> states) throws Exception {
			states
				.withStates()
					.states(EnumSet.allOf(TestStates.class));
		}

		@Override
		public void configure(StateMachineTransitionConfigurer<TestStates, TestEvents> transitions) throws Exception {
			transitions
				.withExternal()
					.source(TestStates.SI)
					.target(TestStates.S1);
		}

	}

	@Configuration
	@EnableStateMachine
	public static class Config3 extends EnumStateMachineConfigurerAdapter<TestStates, TestEvents> {

		@Override
		public void configure(StateMachineStateConfigurer<TestStates, TestEvents> states) throws Exception {
			states
				.withStates()
					.initial(TestStates.SI)
					.state(TestStates.S1);
		}

		@Override
		public void configure(StateMachineTransitionConfigurer<TestStates, TestEvents> transitions) throws Exception {
			transitions
				.withExternal()
					.source(TestStates.SI)
					.target(TestStates.S1)
					.event(TestEvents.E1);
		}

	}
	
	@Override
	protected AnnotationConfigApplicationContext buildContext() {
		return new AnnotationConfigApplicationContext();
	}

}
