/**
 * ============LICENSE_START=======================================================
 * org.onap.aai
 * ================================================================================
 * Copyright © 2017 AT&T Intellectual Property. All rights reserved.
 * Copyright © 2017 Amdocs
 * ================================================================================
 * 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=========================================================
 *
 * ECOMP is a trademark and service mark of AT&T Intellectual Property.
 */
package org.onap.aai.cl.eelf;

import com.att.eelf.configuration.EELFLogger;
import com.att.eelf.configuration.EELFLogger.Level;
import com.att.eelf.i18n.EELFResolvableErrorEnum;
import com.att.eelf.i18n.EELFResourceManager;
import org.onap.aai.cl.api.LogFields;
import org.onap.aai.cl.api.LogLine;
import org.onap.aai.cl.api.LogLine.LogLineType;
import org.onap.aai.cl.api.Logger;
import org.onap.aai.cl.mdc.MdcOverride;

/**
 * This class provides a logging implementation which wraps the EELF logging
 * framework.
 */
public class AaiLoggerAdapter implements Logger {

    public static final String BAD_ENUM_MSG = "UNRECOGNIZABLE ERROR CODE ";

    /** Field name to use for the message portion of our log lines. */
    public static final String MESSAGE_PREFIX = "Msg";

    /**
     * A place holder to use for fields in the standardized log message that we
     * are not explicitly setting.
     */
    private static final String NOT_APPLICABLE = "na";

    /**
     * The instance of the actual EELF logger that we will be sending our messages
     * to.
     */
    private final EELFLogger eelfLogger;

    /**
     * This indicates the logging format type. It is used for deciding the string
     * builder for constructing standardized log statements.
     */
    private final LogLineType logLineType;

    /** An identifier for the component that is generating the log statements. */
    private String component = NOT_APPLICABLE;

    /**
     * Creates a new instance of the {@link AaiLoggerAdapter}, backed by the
     * supplied {@link EELFLogger} instance.
     *
     * @param eelfLogger
     *          - The instance of {@link EELFLogger} that this logger will invoke.
     */
    public AaiLoggerAdapter(EELFLogger eelfLogger, LogLineType logLineType, String componentName) {

        // Store the supplied EELFLogger instance.
        this.eelfLogger = eelfLogger;
        this.logLineType = logLineType;
        component = componentName;
    }

    @Override
    public boolean isTraceEnabled() {
        return eelfLogger.isTraceEnabled();
    }

    @Override
    public boolean isInfoEnabled() {
        return eelfLogger.isInfoEnabled();
    }

    @Override
    public boolean isErrorEnabled() {
        return eelfLogger.isErrorEnabled();
    }

    @Override
    public boolean isWarnEnabled() {
        return eelfLogger.isWarnEnabled();
    }

    @Override
    public boolean isDebugEnabled() {
        return eelfLogger.isDebugEnabled();
    }

    /**
     * Sets a number of the common fields which prefix all standard log
     * statements.
     */
    private void initLogLine(LogLine logLine, String level, String logCode, String msg,
        LogFields fields) {
        logLine.init(component, logCode, level, msg, fields, new MdcOverride());
    }

    private void initLogLine(LogLine logLine, String level, String logCode, String msg,
        LogFields fields, MdcOverride override) {
        logLine.init(component, logCode, level, msg, fields, override);
    }

    @Override
    public void info(Enum logCode, String... arguments) {
        info(logCode, new LogFields(), arguments);
    }

    @Override
    public void info(Enum logCode, LogFields fields, String... arguments) {

        // We expect our error code to be compatible with the templating
        // functionality provided by the EELF framework, so make sure
        // that this is the case before we try to decode our error code.
        if (logCode instanceof LogMessageEnum) {
            // Cast our error code enum to make the EELF framework happy.
            LogMessageEnum eelfLogCode = (LogMessageEnum) logCode;

            // Initialize the log line
            LogLine logLine = getLogLine();
            if (logLine != null) {
                initLogLine(logLine, Level.INFO.toString(), EELFResourceManager.getIdentifier(eelfLogCode),
                    EELFResourceManager.format(eelfLogCode, arguments),
                    fields == null ? new LogFields() : fields);

                // Pass our log string to the EELF logging framework.
                eelfLogger.info(logLine.getFormattedLine());
            }
        } else {
            eelfLogger.error(BAD_ENUM_MSG + logCode);
        }
    }

    @Override
    public void info(Enum logCode, LogFields fields, MdcOverride override, String... arguments) {

        // We expect our error code to be compatible with the templating
        // functionality provided by the EELF framework, so make sure
        // that this is the case before we try to decode our error code.
        if (logCode instanceof LogMessageEnum) {
            // Cast our error code enum to make the EELF framework happy.
            LogMessageEnum eelfLogCode = (LogMessageEnum) logCode;

            // Initialize the log line
            LogLine logLine = getLogLine();
            if (logLine != null) {
                initLogLine(logLine, Level.INFO.toString(), EELFResourceManager.getIdentifier(eelfLogCode),
                    EELFResourceManager.format(eelfLogCode, arguments),
                    fields == null ? new LogFields() : fields, override);

                // Pass our log string to the EELF logging framework.
                eelfLogger.info(logLine.getFormattedLine());
            }
        } else {
            eelfLogger.error(BAD_ENUM_MSG + logCode);
        }
    }

    @Override
    public void debug(String message) {
        // Initialize the log line
        LogLine logLine = getLogLine();
        if (logLine != null) {
            initLogLine(logLine, Level.DEBUG.toString(), "", message, new LogFields());

            // Pass our log string the the EELF logging framework.
            eelfLogger.debug(logLine.getFormattedLine());
        }
    }

    @Override
    public void debug(Enum logCode, String... arguments) {
        debug(logCode, new LogFields(), arguments);
    }

    @Override
    public void debug(Enum logCode, LogFields fields, String... arguments) {

        // We expect our log code to be compatible with the templating
        // functionality provided by the EELF framework, so make sure
        // that this is the case before we try to decode it.
        if (logCode instanceof LogMessageEnum) {
            // Cast our error code enum to make the EELF framework happy.
            LogMessageEnum eelfLogCode = (LogMessageEnum) logCode;

            // Initialize the log lineLogLine logLine = getLogLine()
            LogLine logLine = getLogLine();
            if (logLine != null) {
                initLogLine(logLine, Level.DEBUG.toString(), EELFResourceManager.getIdentifier(eelfLogCode),
                    EELFResourceManager.format(eelfLogCode, arguments),
                    fields == null ? new LogFields() : fields);

                // Pass our log string to the EELF logging framework.
                eelfLogger.debug(logLine.getFormattedLine());
            }
        } else {
            eelfLogger.error(BAD_ENUM_MSG + logCode);
        }
    }

    @Override
    public void warn(Enum logCode, String... arguments) {
        warn(logCode, new LogFields(), arguments);
    }

    @Override
    public void warn(Enum logCode, LogFields fields, String... arguments) {

        // We expect our log code to be compatible with the templating
        // functionality provided by the EELF framework, so make sure
        // that this is the case before we try to decode our it.
        if (logCode instanceof LogMessageEnum) {
            // Cast our error code enum to make the EELF framework happy.
            LogMessageEnum eelfLogCode = (LogMessageEnum) logCode;

            // Initialize the log line
            LogLine logLine = getLogLine();
            if (logLine != null) {
                initLogLine(logLine, Level.WARN.toString(), EELFResourceManager.getIdentifier(eelfLogCode),
                    EELFResourceManager.format(eelfLogCode, arguments),
                    fields == null ? new LogFields() : fields);

                // Pass our log string to the EELF logging framework.
                eelfLogger.warn(logLine.getFormattedLine());
            }
        } else {
            eelfLogger.error(BAD_ENUM_MSG + logCode);
        }
    }

    @Override
    public void trace(Enum logCode, String... arguments) {
        trace(logCode, new LogFields(), arguments);
    }

    @Override
    public void trace(Enum logCode, LogFields fields, String... arguments) {

        // We expect our log code to be compatible with the templating
        // functionality provided by the EELF framework, so make sure
        // that this is the case before we try to decode our it.
        if (logCode instanceof LogMessageEnum) {
            // Cast our error code enum to make the EELF framework happy.
            LogMessageEnum eelfLogCode = (LogMessageEnum) logCode;

            // Initialize the log line
            LogLine logLine = getLogLine();
            if (logLine != null) {
                initLogLine(logLine, Level.TRACE.toString(), EELFResourceManager.getIdentifier(eelfLogCode),
                    EELFResourceManager.format(eelfLogCode, arguments),
                    fields == null ? new LogFields() : fields);

                // Pass our log string to the EELF logging framework.
                eelfLogger.trace(logLine.getFormattedLine());
            }
        } else {
            eelfLogger.error(BAD_ENUM_MSG + logCode);
        }
    }

    @Override
    public void error(Enum logCode, String... arguments) {
        error(logCode, new LogFields(), arguments);
    }

    @Override
    public void error(Enum logCode, LogFields fields, String... arguments) {

        // We expect our log code to be compatible with the templating
        // functionality provided by the EELF framework, so make sure
        // that this is the case before we try to decode it.
        if (logCode instanceof LogMessageEnum) {

            // Cast our error code enum to make the EELF framework happy.
            LogMessageEnum eelfLogCode = (LogMessageEnum) logCode;

            // Initialize the log line
            LogLine logLine = getLogLine();
            if (logLine != null) {
                initLogLine(logLine, Level.ERROR.toString(), EELFResourceManager.getIdentifier(eelfLogCode),
                    EELFResourceManager.format(eelfLogCode, arguments),
                    fields == null ? new LogFields() : fields);

                // Pass our log string to the EELF logging framework.
                eelfLogger.error(logLine.getFormattedLine());
            }
        } else {
            eelfLogger.error(BAD_ENUM_MSG + logCode);
        }
    }

    @Override
    public void error(Enum logCode, Throwable ex, String... arguments) {
        error(logCode, new LogFields(), ex, arguments);
    }

    @Override
    public void error(Enum logCode, LogFields fields, Throwable ex, String... arguments) {

        // We expect our log code to be compatible with the templating
        // functionality provided by the EELF framework, so make sure
        // that this is the case before we try to decode it.
        if (logCode instanceof LogMessageEnum) {
            // Cast our error code enum to make the EELF framework happy.
            LogMessageEnum eelfLogCode = (LogMessageEnum) logCode;

            // Initialize the log line
            LogLine logLine = getLogLine();
            if (logLine != null) {
                initLogLine(logLine, Level.ERROR.toString(), EELFResourceManager.getIdentifier(eelfLogCode),
                    EELFResourceManager.format(eelfLogCode, arguments),
                    fields == null ? new LogFields() : fields);

                // Pass our log string to the EELF logging framework.
                eelfLogger.error(logLine.getFormattedLine(), ex);
            }
        } else {
            eelfLogger.error(BAD_ENUM_MSG + logCode);
        }
    }

    @Override
    public String formatMsg(Enum logCode, String... arguments) {
        return EELFResourceManager.getMessage((EELFResolvableErrorEnum) logCode, arguments);
    }

    private LogLine getLogLine() {
        if (logLineType == LogLineType.AUDIT) {
            return new AuditLogLine();
        }

        if (logLineType == LogLineType.ERROR) {
            return new ErrorLogLine();
        }

        if (logLineType == LogLineType.METRICS) {
            return new MetricsLogLine();
        }

        eelfLogger.warn("Unsupported LogLineType: " + logLineType);
        return null;
    }
}