package org.owasp.webgoat.session;

import org.owasp.webgoat.HammerHead;
import org.owasp.webgoat.lessons.AbstractLesson;
import org.owasp.webgoat.lessons.Category;
import org.owasp.webgoat.plugins.Plugin;
import org.owasp.webgoat.plugins.PluginsLoader;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.servlet.ServletContext;
import java.io.File;
import java.io.IOException;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Set;

/**
 * *************************************************************************************************
 * <p/>
 * <p/>
 * This file is part of WebGoat, an Open Web Application Security Project
 * utility. For details, please see http://www.owasp.org/
 * <p/>
 * Copyright (c) 2002 - 20014 Bruce Mayhew
 * <p/>
 * 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; either version 2 of the License, or (at your option) any later
 * version.
 * <p/>
 * 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.
 * <p/>
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
 * Place - Suite 330, Boston, MA 02111-1307, USA.
 * <p/>
 * Getting Source ==============
 * <p/>
 * Source for this application is maintained at https://github.com/WebGoat/WebGoat, a repository
 * for free software projects.
 * <p/>
 * For details, please see http://webgoat.github.io
 *
 * @author Bruce Mayhew <a href="http://code.google.com/p/webgoat">WebGoat</a>
 * @created October 28, 2003
 */
public class Course {

    final Logger logger = LoggerFactory.getLogger(Course.class);

    private final List<AbstractLesson> lessons = new LinkedList<AbstractLesson>();

    private final static String PROPERTIES_FILENAME = HammerHead.propertiesPath;

    private WebgoatProperties properties = null;

    private final List<String> files = new LinkedList<String>();

    private WebgoatContext webgoatContext;

    public Course() {
        try {
            properties = new WebgoatProperties(PROPERTIES_FILENAME);
        } catch (IOException e) {
            logger.error("Error loading webgoat properties", e);
        }
    }

    /**
     * Take an absolute file and return the filename.
     * <p/>
     * Ex. /etc/password becomes password
     *
     * @param s
     * @return the file name
     */
    private static String getFileName(String s) {
        String fileName = new File(s).getName();

        if (fileName.contains("/")) {
            fileName = fileName.substring(fileName.lastIndexOf("/"), fileName.length());
        }

        if (fileName.contains(".")) {
            fileName = fileName.substring(0, fileName.indexOf("."));
        }

        return fileName;
    }

    /**
     * Take a class name and return the equivalent file name
     * <p/>
     * Ex. org.owasp.webgoat becomes org/owasp/webgoat.java
     *
     * @param className
     * @return
     */
    private static String getSourceFile(String className) {
        StringBuilder sb = new StringBuilder();

        sb.append(className.replace(".", "/"));
        sb.append(".java");

        return sb.toString();
    }

    /**
     * Takes a file name and builds the class file name
     *
     * @param fileName Description of the Parameter
     * @param path     Description of the Parameter
     * @return Description of the Return Value
     */
    private static String getClassFile(String fileName, String path) {
        String ext = ".class";
        fileName = fileName.trim();

        /**
         * We do not handle directories. We do not handle files with different
         * extensions
         */
        if (fileName.endsWith("/") || !fileName.endsWith(ext)) {
            return null;
        }

        // if the file is in /WEB-INF/classes strip the dir info off
        int index = fileName.indexOf("/WEB-INF/classes/");
        if (index != -1) {
            fileName = fileName.substring(index + "/WEB-INF/classes/".length(), fileName.length() - ext.length());
            fileName = fileName.replace('/', '.');
            fileName = fileName.replace('\\', '.');
        } else {
            // Strip off the leading path info
            fileName = fileName.substring(path.length(), fileName.length() - ext.length());
        }

        return fileName;
    }

    /**
     * Gets the categories attribute of the Course object
     *
     * @return The categories value
     */
    public List getCategories() {
        List<Category> categories = new ArrayList<Category>();
        for (AbstractLesson lesson : lessons) {
            if (!categories.contains(lesson.getCategory())) {
                categories.add(lesson.getCategory());
            }
        }

        Collections.sort(categories);

        return categories;
    }

    /**
     * Gets the firstLesson attribute of the Course object
     *
     * @return The firstLesson value
     */
    public AbstractLesson getFirstLesson() {
        List<String> roles = new ArrayList<String>();
        roles.add(AbstractLesson.USER_ROLE);
        // Category 0 is the admin function. We want the first real category
        // to be returned. This is noramally the General category and the Http Basics lesson
        return ((AbstractLesson) getLessons((Category) getCategories().get(0), roles).get(0));
    }

    /**
     * Gets the lesson attribute of the Course object
     *
     * @param s
     * @param lessonId Description of the Parameter
     * @param roles
     * @return The lesson value
     */
    public AbstractLesson getLesson(WebSession s, int lessonId, List<String> roles) {
        if (s.isHackedAdmin()) {
            roles.add(AbstractLesson.HACKED_ADMIN_ROLE);
        }
        // System.out.println("getLesson() with roles: " + roles);
        Iterator<AbstractLesson> iter = lessons.iterator();

        while (iter.hasNext()) {
            AbstractLesson lesson = iter.next();

            // System.out.println("getLesson() at role: " + lesson.getRole());
            if (lesson.getScreenId() == lessonId && roles.contains(lesson.getRole())) {
                return lesson;
            }
        }

        return null;
    }

    public AbstractLesson getLesson(WebSession s, int lessonId, String role) {
        List<String> roles = new ArrayList<String>();
        roles.add(role);
        return getLesson(s, lessonId, roles);
    }

    public List getLessons(WebSession s, String role) {
        List<String> roles = new ArrayList<String>();
        roles.add(role);
        return getLessons(s, roles);
    }

    /**
     * Gets the lessons attribute of the Course object
     *
     * @param s
     * @param roles
     * @return The lessons value
     */
    public List<AbstractLesson> getLessons(WebSession s, List<String> roles) {
        if (s.isHackedAdmin()) {
            roles.add(AbstractLesson.HACKED_ADMIN_ROLE);
        }
        List<AbstractLesson> lessonList = new ArrayList<AbstractLesson>();
        Iterator categoryIter = getCategories().iterator();

        while (categoryIter.hasNext()) {
            lessonList.addAll(getLessons(s, (Category) categoryIter.next(), roles));
        }
        return lessonList;
    }

    /**
     * Gets the lessons attribute of the Course object
     *
     * @param category Description of the Parameter
     * @param role     Description of the Parameter
     * @return The lessons value
     */
    private List<AbstractLesson> getLessons(Category category, List roles) {
        List<AbstractLesson> lessonList = new ArrayList<AbstractLesson>();

        for (AbstractLesson lesson : lessons) {
            if (lesson.getCategory().equals(category) && roles.contains(lesson.getRole())) {
                lessonList.add(lesson);
            }
        }

        Collections.sort(lessonList);
        // System.out.println(java.util.Arrays.asList(lessonList));
        return lessonList;
    }

    public List getLessons(WebSession s, Category category, String role) {
        List<String> roles = new ArrayList<String>();
        roles.add(role);
        return getLessons(s, category, roles);
    }

    public List<AbstractLesson> getLessons(WebSession s, Category category, List<String> roles) {
        if (s.isHackedAdmin()) {
            roles.add(AbstractLesson.HACKED_ADMIN_ROLE);
        }
        return getLessons(category, roles);
    }

    public AbstractLesson getLesson(int lessonId) {
        for (AbstractLesson l : lessons) {
            if (l.getScreenId() == lessonId) {
                return l;
            }
        }
        return null;
    }

    private void loadLessionFromPlugin(ServletContext context) {
        context.getContextPath();
        logger.debug("Loading plugins into cache");
        String pluginPath = context.getRealPath("plugin_lessons");
        String targetPath = context.getRealPath("plugin_extracted");
        if (pluginPath == null) {
            logger.error("Plugins directory {} not found", pluginPath);
            return;
        }
        Path pluginDirectory = Paths.get(pluginPath);
        List<Plugin> plugins = new PluginsLoader(Paths.get(pluginPath), Paths.get(targetPath)).loadPlugins(false);
        for (Plugin plugin : plugins) {
            try {
                Class<AbstractLesson> c = plugin.getLesson();
                Object o = c.newInstance();

                AbstractLesson lesson = (AbstractLesson) o;
                lesson.setWebgoatContext(webgoatContext);

                lesson.update(properties);

                if (lesson.getHidden() == false) {
                    lessons.add(lesson);
                }
                for(Map.Entry<String, File> lessonPlan : plugin.getLessonPlans().entrySet()) {
                    lesson.setLessonPlanFileName(lessonPlan.getKey(), lessonPlan.getValue().toString());
                }
                lesson.setLessonSolutionFileName(plugin.getLessonSolutions().get("en").toString());
                lesson.setSourceFileName(plugin.getLessonSource().toString());
            } catch (Exception e) {
                logger.error("Error in loadLessons: ", e);
            }
        }
    }

    /**
     * Description of the Method
     *
     * @param webgoatContext
     * @param path           Description of the Parameter
     * @param context        Description of the Parameter
     */
    public void loadCourses(WebgoatContext webgoatContext, ServletContext context, String path) {
        logger.info("Loading courses: " + path);
        this.webgoatContext = webgoatContext;
        loadLessionFromPlugin(context);
    }

}