var fs = require('fs');
var path = require('path');

window.onload = function() {
  try {
    var startTime = Date.now();

    process.on('unhandledRejection', function(error, promise) {
      console.error('Unhandled promise rejection %o with error: %o', promise, error);
    });

    // Ensure ATOM_HOME is always set before anything else is required
    setupAtomHome();

    var cacheDir = path.join(process.env.ATOM_HOME, 'compile-cache');
    // Use separate compile cache when sudo'ing as root to avoid permission issues
    if (process.env.USER === 'root' && process.env.SUDO_USER && process.env.SUDO_USER !== process.env.USER) {
      cacheDir = path.join(cacheDir, 'root');
    }

    var rawLoadSettings = decodeURIComponent(location.hash.substr(1));
    var loadSettings;
    try {
      loadSettings = JSON.parse(rawLoadSettings);
    } catch (error) {
      console.error("Failed to parse load settings: " + rawLoadSettings);
      throw error;
    }

    // Normalize to make sure drive letter case is consistent on Windows
    process.resourcesPath = path.normalize(process.resourcesPath);

    var devMode = loadSettings.devMode || !loadSettings.resourcePath.startsWith(process.resourcesPath + path.sep);

    if (loadSettings.profileStartup) {
      profileStartup(cacheDir, loadSettings, Date.now() - startTime);
    } else {
      setupWindow(cacheDir, loadSettings);
      setLoadTime(Date.now() - startTime);
    }
  } catch (error) {
    handleSetupError(error);
  }
}

var setLoadTime = function(loadTime) {
  if (global.atom) {
    global.atom.loadTime = loadTime;
    console.log('Window load time: ' + global.atom.getWindowLoadTime() + 'ms');
  }
}

var handleSetupError = function(error) {
  var currentWindow = require('remote').getCurrentWindow();
  currentWindow.setSize(800, 600);
  currentWindow.center();
  currentWindow.show();
  currentWindow.openDevTools();
  console.error(error.stack || error);
}

var setupWindow = function(cacheDir, loadSettings) {
  setupCoffeeCache(cacheDir);

  ModuleCache = require('../src/module-cache');
  ModuleCache.register(loadSettings);
  ModuleCache.add(loadSettings.resourcePath);

  require('grim').includeDeprecatedAPIs = !loadSettings.apiPreviewMode;

  // Start the crash reporter before anything else.
  require('crash-reporter').start({
    productName: 'Atom',
    companyName: 'GitHub',
    // By explicitly passing the app version here, we could save the call
    // of "require('remote').require('app').getVersion()".
    extra: {_version: loadSettings.appVersion}
  });

  setupVmCompatibility();
  setupCsonCache(cacheDir);
  setupSourceMapCache(cacheDir);
  setupBabel(cacheDir);
  setupTypeScript(cacheDir);

  require(loadSettings.bootstrapScript);
  require('ipc').sendChannel('window-command', 'window:loaded');
}

var setupCoffeeCache = function(cacheDir) {
  var CoffeeCache = require('coffee-cash');
  CoffeeCache.setCacheDirectory(path.join(cacheDir, 'coffee'));
  CoffeeCache.register();
}

var setupAtomHome = function() {
  if (!process.env.ATOM_HOME) {
    var home;
    if (process.platform === 'win32') {
      home = process.env.USERPROFILE;
    } else {
      home = process.env.HOME;
    }
    var atomHome = path.join(home, '.atom');
    try {
      atomHome = fs.realpathSync(atomHome);
    } catch (error) {
      // Ignore since the path might just not exist yet.
    }
    process.env.ATOM_HOME = atomHome;
  }
}

var setupBabel = function(cacheDir) {
  var babel = require('../src/babel');
  babel.setCacheDirectory(path.join(cacheDir, 'js', 'babel'));
  babel.register();
}

var setupTypeScript = function(cacheDir) {
  var typescript = require('../src/typescript');
  typescript.setCacheDirectory(path.join(cacheDir, 'typescript'));
  typescript.register();
}

var setupCsonCache = function(cacheDir) {
  require('season').setCacheDir(path.join(cacheDir, 'cson'));
}

var setupSourceMapCache = function(cacheDir) {
  require('coffeestack').setCacheDirectory(path.join(cacheDir, 'coffee', 'source-maps'));
}

var setupVmCompatibility = function() {
  var vm = require('vm');
  if (!vm.Script.createContext)
    vm.Script.createContext = vm.createContext;
}

var profileStartup = function(cacheDir, loadSettings, initialTime) {
  var profile = function() {
    console.profile('startup');
    try {
      var startTime = Date.now()
      setupWindow(cacheDir, loadSettings);
      setLoadTime(Date.now() - startTime + initialTime);
    } catch (error) {
      handleSetupError(error);
    } finally {
      console.profileEnd('startup');
      console.log("Switch to the Profiles tab to view the created startup profile")
    }
  };

  var currentWindow = require('remote').getCurrentWindow();
  if (currentWindow.devToolsWebContents) {
    profile();
  } else {
    currentWindow.openDevTools();
    currentWindow.once('devtools-opened', function() {
      setTimeout(profile, 100);
    });
  }
}