/*
 * Copyright 2011-2012 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.shell;

import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;

import org.springframework.beans.factory.support.BeanDefinitionRegistry;
import org.springframework.beans.factory.support.DefaultListableBeanFactory;
import org.springframework.beans.factory.support.RootBeanDefinition;
import org.springframework.beans.factory.xml.XmlBeanDefinitionReader;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.ClassPathBeanDefinitionScanner;
import org.springframework.context.support.GenericApplicationContext;
import org.springframework.shell.core.ExitShellRequest;
import org.springframework.shell.core.JLineShellComponent;
import org.springframework.shell.core.Shell;
import org.springframework.shell.support.logging.HandlerUtils;
import org.springframework.util.StopWatch;

/**
 * Loads a {@link Shell} using Spring IoC container.
 * 
 * @author Ben Alex (original Roo code)
 * @author Mark Pollack 
 *
 */
public class Bootstrap {

	private final static String[] CONTEXT_PATH = { "classpath*:/META-INF/spring/spring-shell-plugin.xml" };
	 
	private static Bootstrap bootstrap;
	private static StopWatch sw = new StopWatch("Spring Shell");
	private static CommandLine commandLine;
	
	private GenericApplicationContext ctx;
		

	public static void main(String[] args) throws IOException {
		sw.start();
		ExitShellRequest exitShellRequest;
		try {
			bootstrap = new Bootstrap(args);			
			exitShellRequest = bootstrap.run();
		} catch (RuntimeException t) {
			throw t;
		} finally {
			HandlerUtils.flushAllHandlers(Logger.getLogger(""));
		}

		System.exit(exitShellRequest.getExitCode());
	}

	public Bootstrap(String[] args) throws IOException {	
		this(args, CONTEXT_PATH);
	}
	
	public Bootstrap(String[] args, String[] contextPath) {
		try {
			commandLine = SimpleShellCommandLineOptions.parseCommandLine(args);
        } catch (IOException e) {
            throw new ShellException(e.getMessage(), e);
        }
		
		ctx = new GenericApplicationContext();
		ctx.registerShutdownHook();
		configureApplicationContext(ctx);		
		//built-in commands and converters
		ClassPathBeanDefinitionScanner scanner = new ClassPathBeanDefinitionScanner(ctx);
		scanner.scan("org.springframework.shell.commands", "org.springframework.shell.converters", "org.springframework.shell.plugin.support");
		//user contributed commands
		XmlBeanDefinitionReader reader = new XmlBeanDefinitionReader((BeanDefinitionRegistry) ctx);
		reader.loadBeanDefinitions(contextPath);
		ctx.refresh();
	}
	
	
	public ApplicationContext getApplicationContext() {
		return ctx;
	}

	private void configureApplicationContext(GenericApplicationContext annctx) {
		createAndRegisterBeanDefinition(annctx, org.springframework.shell.converters.StringConverter.class);
		createAndRegisterBeanDefinition(annctx,
				org.springframework.shell.converters.AvailableCommandsConverter.class);
		createAndRegisterBeanDefinition(annctx, org.springframework.shell.converters.BigDecimalConverter.class);
		createAndRegisterBeanDefinition(annctx, org.springframework.shell.converters.BigIntegerConverter.class);
		createAndRegisterBeanDefinition(annctx, org.springframework.shell.converters.BooleanConverter.class);
		createAndRegisterBeanDefinition(annctx, org.springframework.shell.converters.CharacterConverter.class);
		createAndRegisterBeanDefinition(annctx, org.springframework.shell.converters.DateConverter.class);
		createAndRegisterBeanDefinition(annctx, org.springframework.shell.converters.DoubleConverter.class);
		createAndRegisterBeanDefinition(annctx, org.springframework.shell.converters.EnumConverter.class);
		createAndRegisterBeanDefinition(annctx, org.springframework.shell.converters.FloatConverter.class);
		createAndRegisterBeanDefinition(annctx, org.springframework.shell.converters.IntegerConverter.class);
		createAndRegisterBeanDefinition(annctx, org.springframework.shell.converters.LocaleConverter.class);
		createAndRegisterBeanDefinition(annctx, org.springframework.shell.converters.LongConverter.class);
		createAndRegisterBeanDefinition(annctx, org.springframework.shell.converters.ShortConverter.class);
		createAndRegisterBeanDefinition(annctx, org.springframework.shell.converters.StaticFieldConverterImpl.class);
		createAndRegisterBeanDefinition(annctx, org.springframework.shell.core.JLineShellComponent.class, "shell");
		createAndRegisterBeanDefinition(annctx, org.springframework.shell.converters.SimpleFileConverter.class);
		
		annctx.getBeanFactory().registerSingleton("commandLine", commandLine);
	}

	protected void createAndRegisterBeanDefinition(GenericApplicationContext annctx, Class clazz) {
		createAndRegisterBeanDefinition(annctx, clazz, null);
	}

	protected void createAndRegisterBeanDefinition(GenericApplicationContext annctx, Class clazz, String name) {
		RootBeanDefinition rbd = new RootBeanDefinition();
		rbd.setBeanClass(clazz);
		DefaultListableBeanFactory bf = (DefaultListableBeanFactory)annctx.getBeanFactory();
		if (name != null) {
			bf.registerBeanDefinition(name, rbd);
		}
		else {
			bf.registerBeanDefinition(clazz.getSimpleName(), rbd);
		}
	}

	// seems on JDK 1.6.0_18 or higher causes the output to disappear
	private void setupLogging() {
		// Ensure all JDK log messages are deferred until a target is registered
		Logger rootLogger = Logger.getLogger("");
		HandlerUtils.wrapWithDeferredLogHandler(rootLogger, Level.SEVERE);

		// Set a suitable priority level on Spring Framework log messages
		Logger sfwLogger = Logger.getLogger("org.springframework");
		sfwLogger.setLevel(Level.WARNING);

		// Set a suitable priority level on Roo log messages
		// (see ROO-539 and HandlerUtils.getLogger(Class))
		Logger rooLogger = Logger.getLogger("org.springframework.shell");
		rooLogger.setLevel(Level.FINE);
	}


	protected ExitShellRequest run() {

		String[] commandsToExecuteAndThenQuit = commandLine.getShellCommandsToExecute();
		// The shell is used 
		JLineShellComponent shell = ctx.getBean("shell", JLineShellComponent.class);
		ExitShellRequest exitShellRequest;

		if (null != commandsToExecuteAndThenQuit) {
			boolean successful = false;
			exitShellRequest = ExitShellRequest.FATAL_EXIT;

			for (String cmd : commandsToExecuteAndThenQuit) {
				successful = shell.executeCommand(cmd);
				if (!successful)
					break;
			}

			//if all commands were successful, set the normal exit status
			if (successful) {
				exitShellRequest = ExitShellRequest.NORMAL_EXIT;
			}
		}
		else {
			shell.start();
			shell.promptLoop();
			exitShellRequest = shell.getExitShellRequest();
			if (exitShellRequest == null) {
				// shouldn't really happen, but we'll fallback to this anyway
				exitShellRequest = ExitShellRequest.NORMAL_EXIT;
			}
			shell.waitForComplete();
		}

		ctx.close();
		sw.stop();
		if (shell.isDevelopmentMode()) {
			System.out.println("Total execution time: " + sw.getLastTaskTimeMillis() + " ms");
		}
		return exitShellRequest;
	}
	
	JLineShellComponent getJLineShellComponent() {
		return ctx.getBean("shell", JLineShellComponent.class);
	}
}