// Copyright 2006 The Closure Library Authors. 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.

/**
 * @fileoverview Definition of various formatters for logging. Please minimize
 * dependencies this file has on other closure classes as any dependency it
 * takes won't be able to use the logging infrastructure.
 *
 */

goog.provide('goog.debug.Formatter');
goog.provide('goog.debug.HtmlFormatter');
goog.provide('goog.debug.TextFormatter');

goog.require('goog.debug');
goog.require('goog.debug.Logger');
goog.require('goog.debug.RelativeTimeProvider');
goog.require('goog.html.SafeHtml');



/**
 * Base class for Formatters. A Formatter is used to format a LogRecord into
 * something that can be displayed to the user.
 *
 * @param {string=} opt_prefix The prefix to place before text records.
 * @constructor
 */
goog.debug.Formatter = function(opt_prefix) {
  this.prefix_ = opt_prefix || '';

  /**
   * A provider that returns the relative start time.
   * @type {goog.debug.RelativeTimeProvider}
   * @private
   */
  this.startTimeProvider_ =
      goog.debug.RelativeTimeProvider.getDefaultInstance();
};


/**
 * Whether to append newlines to the end of formatted log records.
 * @type {boolean}
 */
goog.debug.Formatter.prototype.appendNewline = true;


/**
 * Whether to show absolute time in the DebugWindow.
 * @type {boolean}
 */
goog.debug.Formatter.prototype.showAbsoluteTime = true;


/**
 * Whether to show relative time in the DebugWindow.
 * @type {boolean}
 */
goog.debug.Formatter.prototype.showRelativeTime = true;


/**
 * Whether to show the logger name in the DebugWindow.
 * @type {boolean}
 */
goog.debug.Formatter.prototype.showLoggerName = true;


/**
 * Whether to show the logger exception text.
 * @type {boolean}
 */
goog.debug.Formatter.prototype.showExceptionText = false;


/**
 * Whether to show the severity level.
 * @type {boolean}
 */
goog.debug.Formatter.prototype.showSeverityLevel = false;


/**
 * Formats a record.
 * @param {goog.debug.LogRecord} logRecord the logRecord to format.
 * @return {string} The formatted string.
 */
goog.debug.Formatter.prototype.formatRecord = goog.abstractMethod;


/**
 * Formats a record as SafeHtml.
 * @param {goog.debug.LogRecord} logRecord the logRecord to format.
 * @return {!goog.html.SafeHtml} The formatted string as SafeHtml.
 */
goog.debug.Formatter.prototype.formatRecordAsHtml = goog.abstractMethod;


/**
 * Sets the start time provider. By default, this is the default instance
 * but can be changed.
 * @param {goog.debug.RelativeTimeProvider} provider The provider to use.
 */
goog.debug.Formatter.prototype.setStartTimeProvider = function(provider) {
  this.startTimeProvider_ = provider;
};


/**
 * Returns the start time provider. By default, this is the default instance
 * but can be changed.
 * @return {goog.debug.RelativeTimeProvider} The start time provider.
 */
goog.debug.Formatter.prototype.getStartTimeProvider = function() {
  return this.startTimeProvider_;
};


/**
 * Resets the start relative time.
 */
goog.debug.Formatter.prototype.resetRelativeTimeStart = function() {
  this.startTimeProvider_.reset();
};


/**
 * Returns a string for the time/date of the LogRecord.
 * @param {goog.debug.LogRecord} logRecord The record to get a time stamp for.
 * @return {string} A string representation of the time/date of the LogRecord.
 * @private
 */
goog.debug.Formatter.getDateTimeStamp_ = function(logRecord) {
  var time = new Date(logRecord.getMillis());
  return goog.debug.Formatter.getTwoDigitString_((time.getFullYear() - 2000)) +
         goog.debug.Formatter.getTwoDigitString_((time.getMonth() + 1)) +
         goog.debug.Formatter.getTwoDigitString_(time.getDate()) + ' ' +
         goog.debug.Formatter.getTwoDigitString_(time.getHours()) + ':' +
         goog.debug.Formatter.getTwoDigitString_(time.getMinutes()) + ':' +
         goog.debug.Formatter.getTwoDigitString_(time.getSeconds()) + '.' +
         goog.debug.Formatter.getTwoDigitString_(
             Math.floor(time.getMilliseconds() / 10));
};


/**
 * Returns the number as a two-digit string, meaning it prepends a 0 if the
 * number if less than 10.
 * @param {number} n The number to format.
 * @return {string} A two-digit string representation of {@code n}.
 * @private
 */
goog.debug.Formatter.getTwoDigitString_ = function(n) {
  if (n < 10) {
    return '0' + n;
  }
  return String(n);
};


/**
 * Returns a string for the number of seconds relative to the start time.
 * Prepads with spaces so that anything less than 1000 seconds takes up the
 * same number of characters for better formatting.
 * @param {goog.debug.LogRecord} logRecord The log to compare time to.
 * @param {number} relativeTimeStart The start time to compare to.
 * @return {string} The number of seconds of the LogRecord relative to the
 *     start time.
 * @private
 */
goog.debug.Formatter.getRelativeTime_ = function(logRecord,
                                                 relativeTimeStart) {
  var ms = logRecord.getMillis() - relativeTimeStart;
  var sec = ms / 1000;
  var str = sec.toFixed(3);

  var spacesToPrepend = 0;
  if (sec < 1) {
    spacesToPrepend = 2;
  } else {
    while (sec < 100) {
      spacesToPrepend++;
      sec *= 10;
    }
  }
  while (spacesToPrepend-- > 0) {
    str = ' ' + str;
  }
  return str;
};



/**
 * Formatter that returns formatted html. See formatRecord for the classes
 * it uses for various types of formatted output.
 *
 * @param {string=} opt_prefix The prefix to place before text records.
 * @constructor
 * @extends {goog.debug.Formatter}
 */
goog.debug.HtmlFormatter = function(opt_prefix) {
  goog.debug.Formatter.call(this, opt_prefix);
};
goog.inherits(goog.debug.HtmlFormatter, goog.debug.Formatter);


/**
 * Whether to show the logger exception text
 * @type {boolean}
 * @override
 */
goog.debug.HtmlFormatter.prototype.showExceptionText = true;


/**
 * Formats a record
 * @param {goog.debug.LogRecord} logRecord the logRecord to format.
 * @return {string} The formatted string as html.
 * @override
 */
goog.debug.HtmlFormatter.prototype.formatRecord = function(logRecord) {
  if (!logRecord) {
    return '';
  }
  // OK not to use goog.html.SafeHtml.unwrap() here.
  return this.formatRecordAsHtml(logRecord).getTypedStringValue();
};


/**
 * Formats a record.
 * @param {goog.debug.LogRecord} logRecord the logRecord to format.
 * @return {!goog.html.SafeHtml} The formatted string as SafeHtml.
 * @override
 */
goog.debug.HtmlFormatter.prototype.formatRecordAsHtml = function(logRecord) {
  if (!logRecord) {
    return goog.html.SafeHtml.EMPTY;
  }

  var className;
  switch (logRecord.getLevel().value) {
    case goog.debug.Logger.Level.SHOUT.value:
      className = 'dbg-sh';
      break;
    case goog.debug.Logger.Level.SEVERE.value:
      className = 'dbg-sev';
      break;
    case goog.debug.Logger.Level.WARNING.value:
      className = 'dbg-w';
      break;
    case goog.debug.Logger.Level.INFO.value:
      className = 'dbg-i';
      break;
    case goog.debug.Logger.Level.FINE.value:
    default:
      className = 'dbg-f';
      break;
  }

  // HTML for user defined prefix, time, logger name, and severity.
  var sb = [];
  sb.push(this.prefix_, ' ');
  if (this.showAbsoluteTime) {
    sb.push('[', goog.debug.Formatter.getDateTimeStamp_(logRecord), '] ');
  }
  if (this.showRelativeTime) {
    sb.push('[',
        goog.debug.Formatter.getRelativeTime_(
            logRecord, this.startTimeProvider_.get()),
        's] ');
  }
  if (this.showLoggerName) {
    sb.push('[', logRecord.getLoggerName(), '] ');
  }
  if (this.showSeverityLevel) {
    sb.push('[', logRecord.getLevel().name, '] ');
  }
  var fullPrefixHtml =
      goog.html.SafeHtml.htmlEscapePreservingNewlinesAndSpaces(sb.join(''));

  // HTML for exception text and log record.
  var exceptionHtml = goog.html.SafeHtml.EMPTY;
  if (this.showExceptionText && logRecord.getException()) {
    exceptionHtml = goog.html.SafeHtml.concat(
        goog.html.SafeHtml.create('br'),
        goog.debug.exposeExceptionAsHtml(logRecord.getException()));
  }
  var logRecordHtml = goog.html.SafeHtml.htmlEscapePreservingNewlinesAndSpaces(
      logRecord.getMessage());
  var recordAndExceptionHtml = goog.html.SafeHtml.create(
      'span',
      {'class': className},
      goog.html.SafeHtml.concat(logRecordHtml, exceptionHtml));


  // Combine both pieces of HTML and, if needed, append a final newline.
  var html;
  if (this.appendNewline) {
    html = goog.html.SafeHtml.concat(fullPrefixHtml, recordAndExceptionHtml,
        goog.html.SafeHtml.create('br'));
  } else {
    html = goog.html.SafeHtml.concat(fullPrefixHtml, recordAndExceptionHtml);
  }
  return html;
};



/**
 * Formatter that returns formatted plain text
 *
 * @param {string=} opt_prefix The prefix to place before text records.
 * @constructor
 * @extends {goog.debug.Formatter}
 * @final
 */
goog.debug.TextFormatter = function(opt_prefix) {
  goog.debug.Formatter.call(this, opt_prefix);
};
goog.inherits(goog.debug.TextFormatter, goog.debug.Formatter);


/**
 * Formats a record as text
 * @param {goog.debug.LogRecord} logRecord the logRecord to format.
 * @return {string} The formatted string.
 * @override
 */
goog.debug.TextFormatter.prototype.formatRecord = function(logRecord) {
  var sb = [];
  sb.push(this.prefix_, ' ');
  if (this.showAbsoluteTime) {
    sb.push('[', goog.debug.Formatter.getDateTimeStamp_(logRecord), '] ');
  }
  if (this.showRelativeTime) {
    sb.push('[', goog.debug.Formatter.getRelativeTime_(logRecord,
        this.startTimeProvider_.get()), 's] ');
  }

  if (this.showLoggerName) {
    sb.push('[', logRecord.getLoggerName(), '] ');
  }
  if (this.showSeverityLevel) {
    sb.push('[', logRecord.getLevel().name, '] ');
  }
  sb.push(logRecord.getMessage());
  if (this.showExceptionText) {
    var exception = logRecord.getException();
    if (exception) {
      var exceptionText = exception instanceof Error ?
          exception.message :
          exception.toString();
      sb.push('\n', exceptionText);
    }
  }
  if (this.appendNewline) {
    sb.push('\n');
  }
  return sb.join('');
};


/**
 * Formats a record as text
 * @param {goog.debug.LogRecord} logRecord the logRecord to format.
 * @return {!goog.html.SafeHtml} The formatted string as SafeHtml. This is
 *     just an HTML-escaped version of the text obtained from formatRecord().
 * @override
 */
goog.debug.TextFormatter.prototype.formatRecordAsHtml = function(logRecord) {
  return goog.html.SafeHtml.htmlEscapePreservingNewlinesAndSpaces(
      goog.debug.TextFormatter.prototype.formatRecord(logRecord));
};
