/**

 * Back 2 Browser Bytecode Translator

 * Copyright (C) 2012 Jaroslav Tulach <jaroslav.tulach@apidesign.org>

 *

 * This program is free software: you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation, version 2 of the License.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program. Look for COPYING file in the top folder.

 * If not, see http://opensource.org/licenses/GPL-2.0.

 */

package org.apidesign.bck2brwsr.vmtest;

import java.lang.annotation.Annotation;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.List;

import org.apidesign.bck2brwsr.launcher.Launcher;

import org.apidesign.bck2brwsr.vmtest.impl.CompareCase;

import org.testng.annotations.Factory;

/** A TestNG {@link Factory} that seeks for {@link Compare} and {@link BrwsrTest} annotations

 * in provided class and builds set of tests that verify the functionality of <b>Bck2Brwsr</b> 

 * based system. Use as:

 * <pre>

 * {@code @}{@link Factory} public static create() {

 *   return @{link VMTest}.{@link #create(java.lang.Class) create}(YourClass.class);

 * }</pre>

 * where <code>YourClass</code> contains methods annotated with

 * {@link Compare} and {@link BrwsrTest} annotations.

 * 

 * @author Jaroslav Tulach <jtulach@netbeans.org>

 */

public final class VMTest {

    private final List<Class> classes = new ArrayList<>();

    private final List<String> launcher = new ArrayList<>();

    private Class<? extends Annotation> annotation = BrwsrTest.class;

    private VMTest() {

    }

    /** Inspects <code>clazz</code> and for each method annotated by

     * {@link Compare} or {@link BrwsrTest} creates

     * instances of tests. 

     * <p>

     * Each {@link Compare} instance runs the test in different virtual

     * machine and at the end they compare the results.

     * <p>

     * Each {@link BrwsrTest} annotated method is executed once in {@link Launcher started

     * browser}.

     * 

     * @param clazz the class (or classes) to inspect

     * @return the set of created tests

     */

    public static Object[] create(Class clazz) {

        return newTests().withClasses(clazz).build();

    }

    /** Creates new builder for test execution. Continue with methods

     * like {@link #withClasses(java.lang.Class[])} or {@link #withLaunchers(java.lang.String[])}.

     * Finish the process by calling {@link #build()}.

     * 

     * @return new instance of a builder

     * @since 0.7

     */

    public static VMTest newTests() {

        return new VMTest();

    }

    /** Adds class (or classes) to the test execution. The classes are inspected

     * to contain methods annotated by

     * {@link Compare} or {@link BrwsrTest}. Appropriate set of TestNG test

     * cases is then created.

     * <p>

     * Each {@link Compare} instance runs the test in different virtual

     * machine and at the end they compare the results.

     * <p>

     * Each {@link BrwsrTest} annotated method is executed once in {@link Launcher started

     * browser}.

     * 

     * @param classes one or more classes to inspect

     * @since 0.7

     */

    public final VMTest withClasses(Class... classes) {

        this.classes.addAll(Arrays.asList(classes));

        return this;

    }

    /** Adds list of launchers that should be used to execute tests defined

     * by {@link Compare} and {@link BrwsrTest} annotations. This value 

     * can be overrided by using <code>vmtest.brwsrs</code> property.

     * List of supported launchers is available in the documentation of

     * {@link Launcher}.

     * 

     * @param launcher names of one or more launchers to use for the execution

     *   of tests

     * @since 0.7

     */

    public final VMTest withLaunchers(String... launcher) {

        this.launcher.addAll(Arrays.asList(launcher));

        return this;

    }

    /** Specifies which annotation annotates the test methods

     * to be executed. By 

     * default it is the {@link BrwsrTest} annotation. Methods in

     * {@link #withClasses(java.lang.Class[]) test classes} annotated by

     * this annotation will be executed.

     * 

     * @param aClass an annotation class 

     * @return this

     * @since 0.8

     */

    public final VMTest withTestAnnotation(Class<? extends Annotation> aClass) {

        if (!aClass.isAnnotation()) {

            throw new IllegalStateException();

        }

        this.annotation = aClass;

        return this;

    }

    /** Assembles the provided information into the final array of tests.

     * @return array of TestNG tests

     * @since 0.7

     */

    public final Object[] build() {

        return CompareCase.create(

            launcher.toArray(new String[0]), 

            classes.toArray(new Class[0]),

            annotation

        );

    }

}