var Log = require('../../src/lib/log');
var FileLogger = require('../../src/lib/loggers/file');
var once = require('events').EventEmitter.prototype.once;
var _ = require('lodash');
var parentLog;
var logger;
var fs = require('fs');

beforeEach(function () {
  parentLog = new Log();
});

afterEach(function () {
  parentLog.close();

  if (logger
    && logger.stream
    && logger.stream._writableState
    && logger.stream._writableState.buffer.length
  ) {
    // empty the buffer manually
    logger.stream._writableState.buffer.splice(0);
  }
});

function makeLogger(parent, levels) {
  parent = parent || parentLog;
  logger = new FileLogger(parent, {
    levels: Log.parseLevels(levels || 'trace'),
    path: 'test.log'
  });
  return logger;
}

var stub = require('./auto_release_stub').make();

describe('File Logger', function () {
  require('./generic_logger_tests')(makeLogger);

  describe('buffer flush', function () {
    if (require('stream').Writable) {
      it('writes everything in the buffer to console.error', function () {
        var line = 'This string is written 10 times to create buffered output\n';

        var exitHandler;
        stub(process, 'once', function (event, handler) {
          if (event === 'exit') {
            exitHandler = handler;
          }
          once.call(process, event, handler);
        });

        var logger = makeLogger();

        // write the line 10 times
        _.times(10, function () {
          logger.onDebug(line);
        });

        // collect everything that is written to fs.appendFileSync
        var flushedOutput = '';
        stub(fs, 'appendFileSync', function (path, str) {
          flushedOutput += str;
        });

        // call the event handler
        exitHandler.call(process);

        // the first line is sent immediately to _write and there is nothing we can do about that
        flushedOutput.should.match(new RegExp(line));
        flushedOutput.match(new RegExp(line, 'g')).length.should.eql(9);
      });
    } else {
      it('does not fall apart with non streams2 streams', function () {
        var exitHandler;
        stub(process, 'once', function (event, handler) {
          if (event === 'exit') {
            exitHandler = handler;
          }
          once.call(process, event, handler);
        });

        var logger = makeLogger();

        (function () {
          // call the event handler
          exitHandler.call(process);
        }).should.not.throw();
      });
    }
  });
});