/* 
 * 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.felix.ipojo.junit4osgi.impl;

import java.io.PrintStream;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

import junit.framework.Test;
import junit.framework.TestResult;
import junit.framework.TestSuite;

import org.apache.felix.ipojo.junit4osgi.OSGiJunitRunner;
import org.apache.felix.ipojo.junit4osgi.OSGiTestCase;
import org.apache.felix.ipojo.junit4osgi.OSGiTestSuite;
import org.apache.felix.ipojo.parser.ParseUtils;
import org.osgi.framework.Bundle;
import org.osgi.framework.BundleContext;

/**
 * Detect test suite from installed bundles.
 * @author <a href="mailto:dev@felix.apache.org">Felix Project Team</a>
 */
public class JunitExtender implements OSGiJunitRunner {

    public static final String SUITE_METHODNAME = "suite";

    private Map/*<Bundle, List<Class>>*/ m_suites = new HashMap/*<Bundle, List<Class>>*/();

    private ResultPrinter m_printer = new ResultPrinter(System.out);

    void onBundleArrival(Bundle bundle, String header) {
        String[] tss = ParseUtils.split(header, ",");
        for (int i = 0; i < tss.length; i++) {
            try {
                if (tss[i].length() != 0) {
                    System.out.println("Loading " + tss[i]);
                    Class/*<? extends Test>*/ clazz = bundle.loadClass(tss[i].trim());
                    addTestSuite(bundle, clazz);
                }
            } catch (ClassNotFoundException e) {
                System.err.println("The test suite " + tss[i] + " is not in the bundle " + bundle.getBundleId() + " : " + e.getMessage());
            }
        }
    }

    private synchronized void addTestSuite(Bundle bundle, Class/*<? extends Test>*/ test) {
        List/*<Class>*/ list = (List) m_suites.get(bundle);
        if (list == null) {
            list = new ArrayList/*<Class>*/();
            list.add(test);
            m_suites.put(bundle, list);
        } else {
            list.add(test);
        }
    }

    private synchronized void removeTestSuites(Bundle bundle) {
        List list = (List) m_suites.remove(bundle);
        System.out.println("Unload test suites " + list);
    }

    void onBundleDeparture(Bundle bundle) {
        removeTestSuites(bundle);
    }

    public void setResultPrinter(PrintStream pw) {
        m_printer = new ResultPrinter(pw);
    }

    public synchronized List/*<TestResult>*/ run() {
        List/*<TestResult>*/ results = new ArrayList/*<TestResult>*/(m_suites.size());
        Iterator/*<Entry<Bundle, List<Class>>>*/ it = m_suites.entrySet().iterator();
        while (it.hasNext()) {
            Entry/*<Bundle, List<Class>>*/ entry = (Entry) it.next();
            Bundle bundle = (Bundle) entry.getKey();
            List/*<Class>*/ list = (List) m_suites.get(bundle);
            for (int i = 0; i < list.size(); i++) {
                Test test = createTestFromClass((Class)list.get(i), bundle);
                TestResult tr = doRun(test);
                results.add(tr);
            }
        }
        return results;
    }

    private TestResult doRun(Test test) {
        TestResult result = new TestResult();
        result.addListener(m_printer);
        long startTime = System.currentTimeMillis();

        test.run(result);

        long endTime = System.currentTimeMillis();
        long runTime = endTime - startTime;
        m_printer.print(result, runTime);

        return result;
    }

    private Test createTestFromClass(Class/*<?>*/ clazz, Bundle bundle) {
        Method suiteMethod = null;
        boolean bc = false;
        try {
            suiteMethod = clazz.getMethod(SUITE_METHODNAME, new Class[0]);
        } catch (Exception e) {
            // try to use a suite method receiving a bundle context
            try {
                suiteMethod = clazz.getMethod(SUITE_METHODNAME, new Class[] { BundleContext.class });
                bc = true;
            } catch (Exception e2) {
                // try to extract a test suite automatically
                if (OSGiTestSuite.class.isAssignableFrom(clazz)) {
                    OSGiTestSuite ts = new OSGiTestSuite(clazz, getBundleContext(bundle));
                    return ts;
                } else if (OSGiTestCase.class.isAssignableFrom(clazz)) {
                    OSGiTestSuite ts = new OSGiTestSuite(clazz, getBundleContext(bundle));
                    return ts;
                } else {
                    return new TestSuite(clazz);
                }
            }
        }

        if (!Modifier.isStatic(suiteMethod.getModifiers())) {
            System.err.println("Suite() method must be static");
            return null;
        }
        Test test = null;
        try {
            if (bc) {
                test = (Test) suiteMethod.invoke(null, new Object[] { getBundleContext(bundle) }); // static method injection the bundle context
            } else {
                test = (Test) suiteMethod.invoke(null, (Object[]) new Class[0]); // static method
            }
        } catch (InvocationTargetException e) {
            System.err.println("Failed to invoke suite():" + e.getTargetException().toString());
            return null;
        } catch (IllegalAccessException e) {
            System.err.println("Failed to invoke suite():" + e.toString());
            return null;
        }

        return test;
    }

    public synchronized List/*<Test>*/ getTests() {
        List/*<Test>*/ results = new ArrayList/*<Test>*/();
        Iterator/*<Entry<Bundle, List<Class>>>*/ it = m_suites.entrySet().iterator();
        while (it.hasNext()) {
            Entry/*<Bundle, List<Class>>*/ entry = (Entry) it.next();
            Bundle bundle = (Bundle) entry.getKey();
            List/*<Class>*/ list = (List) m_suites.get(bundle);
            for (int i = 0; i < list.size(); i++) {
                Test test = createTestFromClass((Class) list.get(i), bundle);
                results.add(test);
            }
        }
        return results;
    }

    public TestResult run(Test test) {
        return doRun(test);
    }

    public synchronized List/*<Test>*/ getTests(long bundleId) {
        Iterator/*<Entry<Bundle, List<Class>>>*/ it = m_suites.entrySet().iterator();
        while (it.hasNext()) {
            Entry/*<Bundle, List<Class>>*/ entry = (Entry) it.next();
            Bundle bundle = (Bundle) entry.getKey();
            if (bundle.getBundleId() == bundleId) {
                List/*<Test>*/ results = new ArrayList/*<Test>*/();
                List/*<Class>*/ list = (List) m_suites.get(bundle);
                for (int i = 0; i < list.size(); i++) {
                    Test test = createTestFromClass((Class) list.get(i), bundle);
                    results.add(test);
                }
                return results;
            }
        }
        return null;
    }

    public synchronized List/*<TestResult>*/ run(long bundleId) {
        Iterator/*<Entry<Bundle, List<Class>>>*/ it = m_suites.entrySet().iterator();
        while (it.hasNext()) {
            Entry/*<Bundle, List<Class>>*/ entry = (Entry) it.next();
            Bundle bundle = (Bundle) entry.getKey();
            if (bundle.getBundleId() == bundleId) {
                List/*<TestResult>*/ results = new ArrayList/*<TestResult>*/();
                List/*<Class>*/ list = (List) m_suites.get(bundle);
                for (int i = 0; i < list.size(); i++) {
                    Test test = createTestFromClass((Class) list.get(i), bundle);
                    TestResult tr = doRun(test);
                    results.add(tr);
                }
                return results;
            }
        }
        return null;
    }

    public synchronized void stopping() {
        System.out.println("Cleaning test suites ...");
        m_suites.clear();
    }
    
    public void starting() {
        System.out.println("Junit Extender starting ...");
    }

    private BundleContext getBundleContext(Bundle bundle) {
        if (bundle == null) { return null; }

        // getBundleContext (OSGi 4.1)
        Method meth = null;
        try {
            meth = bundle.getClass().getMethod("getBundleContext", new Class[0]);
        } catch (SecurityException e) {
            // Nothing do to, will try the Equinox method
        } catch (NoSuchMethodException e) {
            // Nothing do to, will try the Equinox method
        }

        // try Equinox getContext if not found.
        if (meth == null) {
            try {
                meth = bundle.getClass().getMethod("getContext", new Class[0]);
            } catch (SecurityException e) {
                // Nothing do to, will try field inspection
            } catch (NoSuchMethodException e) {
                // Nothing do to, will try field inspection
            }
        }

        if (meth != null) {
            if (! meth.isAccessible()) {
                meth.setAccessible(true);
            }
            try {
                return (BundleContext) meth.invoke(bundle, new Object[0]);
            } catch (IllegalArgumentException e) {
                err("Cannot get the BundleContext by invoking " + meth.getName(), e);
                return null;
            } catch (IllegalAccessException e) {
                err("Cannot get the BundleContext by invoking " + meth.getName(), e);
                return null;
            } catch (InvocationTargetException e) {
                err("Cannot get the BundleContext by invoking " + meth.getName(), e);
                return null;
            }
        }

        // Else : Field inspection (KF and Prosyst)        
        Field[] fields = bundle.getClass().getDeclaredFields();
        for (int i = 0; i < fields.length; i++) {
            if (BundleContext.class.isAssignableFrom(fields[i].getType())) {
                if (! fields[i].isAccessible()) {
                    fields[i].setAccessible(true);
                }
                try {
                    return (BundleContext) fields[i].get(bundle);
                } catch (IllegalArgumentException e) {
                    err("Cannot get the BundleContext by invoking " + meth.getName(), e);
                    return null;
                } catch (IllegalAccessException e) {
                    err("Cannot get the BundleContext by invoking " + meth.getName(), e);
                    return null;
                }
            }
        }
        err("Cannot find the BundleContext for " + bundle.getSymbolicName(), null);
        return null;
    }

    private void err(String s, Throwable e) {
        System.err.println(s + " : " + e.getMessage());
    }

}