const electronSettings = require("electron-settings");

const electron = require("electron");
const isDev = require("electron-is-dev");
const app = electron.app;
const app_version_as_string = app.getVersion().replace(/\./g, "_") + (isDev ? "-dev" : "");

function storageHaveCurrentVersion() {
  return typeof electronSettings.get(app_version_as_string) === "object";
}

function getAllAvailableVersion() {
  var keys = Object.keys(electronSettings.getAll());
  var versionAsRegex = isDev
    ? /^\d*_\d*_\d*(-dev)$/
    : /^\d*_\d*_\d*$/;
  var validKeys = keys.filter((val, index) => {
    return versionAsRegex.test(val);
  });
  validKeys.push(app_version_as_string);
  validKeys.sort((a, b) => {
    return a.localeCompare(b);
  });
  return validKeys;
}

function storageHasPreviousVersion() {
  var validKeys = getAllAvailableVersion();
  return validKeys.indexOf(app_version_as_string) > 0;
}

function getPreviousVersion() {
  var validKeys = getAllAvailableVersion();
  const index = validKeys.indexOf(app_version_as_string);
  return validKeys[index-1];
}

function from_2_0_0_MoveAppContext(previousVersion) {
  electronSettings.set(
    `${app_version_as_string}.appContext`,
    electronSettings.get(previousVersion)
  );
}
function from_2_0_0_MoveLightMode() {
  electronSettings.set(
    `${app_version_as_string}.lightMode`,
    electronSettings.get("lightMode")
  );
}
function from_2_0_0_MoveLocale() {
  electronSettings.set(
    `${app_version_as_string}.locale`,
    electronSettings.get("locale")
  );
}
function from_2_0_0_MoveReApplyPeriodically() {
  electronSettings.set(
    `${app_version_as_string}.reApplyPeriodically`,
    electronSettings.get("reApplyPeriodically")
  );
}
function from_2_0_0_MoveVotedPresets() {
  electronSettings.set(
    `${app_version_as_string}.votedPresets`,
    electronSettings.get("votedPresets")
  );
}

function upgradeFromPreviousVersion() {
  isDev && console.log('Upgrading storage...');
  const previousVersion = getPreviousVersion();
  switch (previousVersion) {
    case "2_0_0":
    case "2_0_0-dev":
      from_2_0_0_MoveAppContext(previousVersion);
      from_2_0_0_MoveLightMode(previousVersion);
      from_2_0_0_MoveLocale(previousVersion);
      from_2_0_0_MoveReApplyPeriodically(previousVersion);
      from_2_0_0_MoveVotedPresets(previousVersion);
      isDev && console.log('... from 2.0.0');
      break;
  
    default:
      break;
  }

}

const upgrader = () => {
  if (storageHaveCurrentVersion()) {
    // No need to upgrade.
    return;
  }
  if (!storageHasPreviousVersion()) {
    // No need to upgrade.
    return;
  }
  upgradeFromPreviousVersion();
};

module.exports = upgrader;