/**
 * ============LICENSE_START====================================================
 * org.onap.aaf
 * ===========================================================================
 * Copyright (c) 2018 AT&T Intellectual Property. All rights reserved.
 * ===========================================================================
 * 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.
 * ============LICENSE_END====================================================
 *
 */

package org.onap.aaf.cadi;

import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;

/**
 * Various Environments require different logging mechanisms, or at least allow
 * for different ones. We need the Framework to be able to hook into any particular instance of logging
 * mechanism, whether it be a Logging Object within a Servlet Context, or a direct library like log4j.
 * This interface, therefore, allows maximum pluggability in a variety of different app styles.
 *
 * @author Jonathan
 *
 */
public interface Access {
    // levels to use
    public enum Level {
        DEBUG(0x1), INFO(0x10), AUDIT(0x100), WARN(0x2000), ERROR(0x4000), INIT(0x8000),TRACE(0x10000),NONE(0XFFFF);
        private final int bit;

        Level(int ord) {
            bit = ord;
        }

        public boolean inMask(int mask) {
            return (mask & bit) == bit;
        }

        public int addToMask(int mask) {
            return mask | bit;
        }

        public int delFromMask(int mask) {
            return mask & ~bit;
        }

        public int toggle(int mask) {
            if (inMask(mask)) {
                return delFromMask(mask);
            } else {
                return addToMask(mask);
            }
        }


        public int maskOf() {
            int mask=0;
            for (Level l : values()) {
                if (ordinal()<=l.ordinal() && l!=NONE) {
                    mask|=l.bit;
                }
            }
            return mask;
        }
    }

    /**
     * Write a variable list of Object's text via the toString() method with appropriate space, etc.
     * @param elements
     */
    public void log(Level level, Object ... elements);

    /**
     * Printf mechanism for Access
     * @param level
     * @param fmt
     * @param elements
     */
    public void printf(Level level, String fmt, Object ... elements);

    /**
     * Check if message will log before constructing
     * @param level
     * @return
     */
    public boolean willLog(Level level);

    /**
     * Write the contents of an exception, followed by a variable list of Object's text via the
     * toString() method with appropriate space, etc.
     *
     * The Loglevel is always "ERROR"
     *
     * @param elements
     */
    public void log(Exception e, Object ... elements);

    /**
     * Set the Level to compare logging too
     */
    public void setLogLevel(Level level);

    /**
     * It is important in some cases to create a class from within the same Classloader that created
     * Security Objects.  Specifically, it's pretty typical for Web Containers to separate classloaders
     * so as to allow Apps with different dependencies.
     * @return
     */
    public ClassLoader classLoader();

    public String getProperty(String string, String def);

    public Properties getProperties();

    public void load(InputStream is) throws IOException;

    /**
     * if "anytext" is true, then decryption will always be attempted.  Otherwise, only if starts with
     * Symm.ENC
     * @param encrypted
     * @param anytext
     * @return
     * @throws IOException
     */
    public String decrypt(String encrypted, boolean anytext) throws IOException;

    public static final Access NULL = new Access() {
        public void log(Level level, Object... elements) {
        }

        @Override
        public void printf(Level level, String fmt, Object... elements) {
        }

        public void log(Exception e, Object... elements) {
        }

        public ClassLoader classLoader() {
            return ClassLoader.getSystemClassLoader();
        }

        public String getProperty(String string, String def) {
            return null;
        }

        public void load(InputStream is) throws IOException {
        }

        public void setLogLevel(Level level) {
        }

        public String decrypt(String encrypted, boolean anytext) throws IOException {
            return encrypted;
        }

        @Override
        public boolean willLog(Level level) {
            return false;
        }

        @Override
        public Properties getProperties() {
            return new Properties();
        }
    };


}