/**
 * Copyright 2014 Google Inc.
 *
 * 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.
 *
 * @fileoverview Implements log functions which can be compiled out.
 */

goog.provide('shaka.log');


/**
 * @namespace shaka.log
 * @summary A console logging framework which is compiled out for deployment.
 */


/**
 * Log levels.
 * @enum {number}
 */
shaka.log.Level = {
  NONE: 0,
  ERROR: 1,
  WARNING: 2,
  INFO: 3,
  DEBUG: 4,
  V1: 5,
  V2: 6
};


/**
 * @define {number} the maximum log level.
 */
goog.define('shaka.log.MAX_LOG_LEVEL', 3);


/** @type {function(*, ...*)} */
shaka.log.error = function() {};


/** @type {function(*, ...*)} */
shaka.log.warning = function() {};


/** @type {function(*, ...*)} */
shaka.log.info = function() {};


/** @type {function(*, ...*)} */
shaka.log.debug = function() {};


/** @type {function(*, ...*)} */
shaka.log.v1 = function() {};


/** @type {function(*, ...*)} */
shaka.log.v2 = function() {};


/**
 * @private
 * @param {string} logName
 */
shaka.log.patchConsole_ = function(logName) {
  var nop = function() {};
  var logFunction = console[logName];

  if (!logFunction) {
    console[logName] = nop;
  } else if (!logFunction.bind) {
    // IE 9 does not provide a .bind for the built-in logging functions.
    console[logName] = function() {
      logFunction.apply(console, arguments);
    };
  }
};

shaka.log.patchConsole_('error');
shaka.log.patchConsole_('warn');
shaka.log.patchConsole_('info');
shaka.log.patchConsole_('log');
shaka.log.patchConsole_('debug');

if (!COMPILED) {
  /**
   * Change the log level.  Useful for debugging in uncompiled mode.
   *
   * @param {number} level
   */
  shaka.log.setLevel = function(level) {
    var nop = function() {};
    var log = shaka.log;
    var Level = shaka.log.Level;

    log.error = (level >= Level.ERROR) ? console.error.bind(console) : nop;
    log.warning = (level >= Level.WARNING) ? console.warn.bind(console) : nop;
    log.info = (level >= Level.INFO) ? console.info.bind(console) : nop;
    log.debug = (level >= Level.DEBUG) ? console.log.bind(console) : nop;
    log.v1 = (level >= Level.V1) ? console.debug.bind(console) : nop;
    log.v2 = (level >= Level.V2) ? console.debug.bind(console) : nop;
  };
}


// Although these bindings are redundant with setLevel() above, refactoring to
// call a method here makes it so that the log messages themselves cannot be
// compiled out.

if (shaka.log.MAX_LOG_LEVEL >= shaka.log.Level.ERROR) {
  shaka.log.error = console.error.bind(console);
}

if (shaka.log.MAX_LOG_LEVEL >= shaka.log.Level.WARNING) {
  shaka.log.warning = console.warn.bind(console);
}

if (shaka.log.MAX_LOG_LEVEL >= shaka.log.Level.INFO) {
  shaka.log.info = console.info.bind(console);
}

if (shaka.log.MAX_LOG_LEVEL >= shaka.log.Level.DEBUG) {
  shaka.log.debug = console.log.bind(console);
}

if (shaka.log.MAX_LOG_LEVEL >= shaka.log.Level.V1) {
  shaka.log.v1 = console.debug.bind(console);
}

if (shaka.log.MAX_LOG_LEVEL >= shaka.log.Level.V2) {
  shaka.log.v2 = console.debug.bind(console);
}