var async = require('async');
var fs = require('fs.extra');
var path = require('path');
var userhome = require('userhome');

var Logs = function (config) {
  this.config = config;

  if (this.config.type === 'linux') {
    fs.mkdirp(this.logsPath());
  }
};

Logs.generateLogFileName = function () {
  var dateStr = new Date().toISOString().
    replace(/:/g, '-'). // Replace time dividers with dash
    replace(/T/, '_'). // Remove date and time divider
    replace(/\..+/, ''); // Remove milliseconds
  return 'arma3server_' + dateStr + '.log';
};

Logs.prototype.generateLogFilePath = function () {
  return path.join(this.logsPath(), Logs.generateLogFileName());
};

Logs.prototype.logsPath = function () {
  if (this.config.type === 'linux') {
    return path.join(this.config.path, 'logs');
  }

  if (this.config.type === 'windows') {
    return userhome('AppData', 'Local', 'Arma 3');
  }

  if (this.config.type === 'wine') {
    var username = process.env.USER;
    return userhome('.wine', 'drive_c', 'users', username, 'Local Settings', 'Application Data', 'Arma 3');
  }

  return null;
};

Logs.prototype.logFiles = function (callback) {
  var directory = this.logsPath();

  if (directory === null) {
    callback(null, []);
  }

  fs.readdir(directory, function (err, files) {
    if (err) {
      callback (err);
      return;
    }

    files = files.map(function (file) {
      return {
        name: file,
        path: path.join(directory, file),
      };
    });

    async.filter(files, function(file, cb) {
      fs.stat(file.path, function (err, stat) {
        file.size = stat.size;
        cb(!err && stat.isFile());
      });
    }, function (files) {
      files.sort(function (a, b) {
        return a.name.toLowerCase().localeCompare(b.name.toLowerCase());
      });

      callback(null, files);
    });
  });
};

Logs.prototype.getLogFile = function (filename, callback) {
  this.logFiles(function (err, files) {
    if (err) {
      callback(err);
    } else {
      var validLogs = files.filter(function (file) {
        return file.name === filename;
      });

      if (validLogs.length > 0) {
        callback(null, validLogs[0]);
      } else {
        callback(null, null);
      }
    }
  });
};

module.exports = Logs;