package org.junit.internal.runners;

import java.lang.annotation.Annotation;

import java.lang.reflect.Method;

import java.util.ArrayList;

import java.util.Collections;

import java.util.List;

import org.junit.Before;

import org.junit.BeforeClass;

import org.junit.Ignore;

import org.junit.Test;

import org.junit.Test.None;

public class TestIntrospector {

	private final Class< ?> fTestClass;

	public TestIntrospector(Class<?> testClass) {

		fTestClass= testClass;

	}

	public List<Method> getTestMethods(Class<? extends Annotation> annotationClass) {

		List<Method> results= new ArrayList<Method>();

		for (Class<?> eachClass : getSuperClasses(fTestClass)) {

			Method[] methods= eachClass.getDeclaredMethods();

			for (Method eachMethod : methods) {

				Annotation annotation= eachMethod.getAnnotation(annotationClass);

				if (annotation != null && ! isShadowed(eachMethod, results)) 

					results.add(eachMethod);

			}

		}

		if (runsTopToBottom(annotationClass))

			Collections.reverse(results);

		return results;

	}

	public boolean isIgnored(Method eachMethod) {

		return eachMethod.getAnnotation(Ignore.class) != null;

	}

	private boolean runsTopToBottom(Class< ? extends Annotation> annotation) {

		return annotation.equals(Before.class) || annotation.equals(BeforeClass.class);

	}

	private boolean isShadowed(Method method, List<Method> results) {

		for (Method each : results) {

			if (isShadowed(method, each))

				return true;

		}

		return false;

	}

	private boolean isShadowed(Method current, Method previous) {

		if (! previous.getName().equals(current.getName()))

			return false;

		if (previous.getParameterTypes().length != current.getParameterTypes().length)

			return false;

		for (int i= 0; i < previous.getParameterTypes().length; i++) {

			if (! previous.getParameterTypes()[i].equals(current.getParameterTypes()[i]))

				return false;

		}

		return true;

	}

	private List<Class<?>> getSuperClasses(Class< ?> testClass) {

		ArrayList<Class<?>> results= new ArrayList<Class<?>>();

		Class<?> current= testClass;

		while (current != null) {

			results.add(current);

			current= current.getSuperclass();

		}

		return results;

	}

	long getTimeout(Method method) {

		Test annotation= method.getAnnotation(Test.class);

		long timeout= annotation.timeout();

		return timeout;

	}

	Class<? extends Throwable> expectedException(Method method) {

		Test annotation= method.getAnnotation(Test.class);

		if (annotation.expected() == None.class)

			return null;

		else

			return annotation.expected();

	}

}