ui/views/RecyclerView/kotlinApp/app/src/main/java/com/example/android/common/logger/Log.kt

/*
 * Copyright (C) 2017 The Android Open Source Project
 *
 * 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.
 */
package com.example.android.common.logger

/**
 * Helper class for a list (or tree) of LoggerNodes.
 *
 *
 * When this is set as the head of the list,
 * an instance of it can function as a drop-in replacement for [android.util.Log].
 * Most of the methods in this class server only to map a method call in Log to its equivalent
 * in LogNode.
 */
object Log {
    // Grabbing the native values from Android's native logging facilities,
    // to make for easy migration and interop.
    val NONE = -1
    val VERBOSE = android.util.Log.VERBOSE
    val DEBUG = android.util.Log.DEBUG
    val INFO = android.util.Log.INFO
    val WARN = android.util.Log.WARN
    val ERROR = android.util.Log.ERROR
    val ASSERT = android.util.Log.ASSERT

    // Stores the beginning of the LogNode topology.
    var logNode: LogNode? = null

    /**
     * Instructs the LogNode to print the log data provided. Other LogNodes can
     * be chained to the end of the LogNode as desired.
     *
     * @param priority Log level of the data being logged. Verbose, Error, etc.
     * @param tag Tag for for the log data. Can be used to organize log statements.
     * @param msg The actual message to be logged.
     * @param tr If an exception was thrown, this can be sent along for the logging facilities
     * to extract and print useful information.
     */
    fun println(priority: Int, tag: String, msg: String?, tr: Throwable? = null) {

        logNode?.println(priority, tag, msg, tr)

    }

    /**
     * Prints a message at VERBOSE priority.
     *
     * @param tag Tag for for the log data. Can be used to organize log statements.
     * @param msg The actual message to be logged.
     * @param tr If an exception was thrown, this can be sent along for the logging facilities
     * to extract and print useful information.
     */
    fun v(tag: String, msg: String? = null, tr: Throwable? = null) {
        println(VERBOSE, tag, msg, tr)
    }


    /**
     * Prints a message at DEBUG priority.
     *
     * @param tag Tag for for the log data. Can be used to organize log statements.
     * @param msg The actual message to be logged.
     * @param tr If an exception was thrown, this can be sent along for the logging facilities
     * to extract and print useful information.
     */
    fun d(tag: String, msg: String? = null, tr: Throwable? = null) {
        println(DEBUG, tag, msg, tr)
    }

    /**
     * Prints a message at INFO priority.
     *
     * @param tag Tag for for the log data. Can be used to organize log statements.
     * @param msg The actual message to be logged.
     * @param tr If an exception was thrown, this can be sent along for the logging facilities
     * to extract and print useful information.
     */
    fun i(tag: String, msg: String, tr: Throwable? = null) {
        println(INFO, tag, msg, tr)
    }

    /**
     * Prints a message at WARN priority.
     *
     * @param tag Tag for for the log data. Can be used to organize log statements.
     * @param msg The actual message to be logged.
     * @param tr If an exception was thrown, this can be sent along for the logging facilities
     * to extract and print useful information.
     */
    fun w(tag: String, msg: String? = null, tr: Throwable? = null) {
        println(WARN, tag, msg, tr)
    }



    /**
     * Prints a message at ERROR priority.
     *
     * @param tag Tag for for the log data. Can be used to organize log statements.
     * @param msg The actual message to be logged.
     * @param tr If an exception was thrown, this can be sent along for the logging facilities
     * to extract and print useful information.
     */
    fun e(tag: String, msg: String, tr: Throwable? = null) {
        println(ERROR, tag, msg, tr)
    }

    /**
     * Prints a message at ASSERT priority.
     *
     * @param tag Tag for for the log data. Can be used to organize log statements.
     * @param msg The actual message to be logged.
     * @param tr If an exception was thrown, this can be sent along for the logging facilities
     * to extract and print useful information.
     */
    fun wtf(tag: String, msg: String? = null, tr: Throwable? = null) {
        println(ASSERT, tag, msg, tr)
    }


}