/**
 * Copyright 2013-2017  Zaid Abdulla
 *
 * This file is part of GenieACS.
 *
 * GenieACS is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * GenieACS is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with GenieACS.  If not, see <http://www.gnu.org/licenses/>.
 */
"use strict";

const config = require("./config");
const common = require("./common");
const device = require("./device");

const MAX_DEPTH = config.get("MAX_DEPTH");


function refresh(sessionContext, provision, declarations, startRevision, endRevision) {
  let path = common.parsePath(provision[1]).slice();
  let l = path.length;
  path.length = MAX_DEPTH;
  path.fill("*", l);
  let every = 1000 * (provision[2] || 1);
  let offset = Math.abs(common.djb2(sessionContext.deviceId)) % 86400000;
  let t = Math.trunc((sessionContext.timestamp + offset) / every) * every - offset;

  for (let i = l; i < path.length; ++ i)
    declarations.push([path.slice(0, i), t, {object: 1, writable: 1, value: t}]);

  return true;
}


function value(sessionContext, provision, declarations, startRevision, endRevision) {
  let path = common.parsePath(provision[1]);
  declarations.push([path, 1, {value: 1}, null, {value: [provision[2]]}]);

  return true;
}


function tag(sessionContext, provision, declarations, startRevision, endRevision) {
  let path = ["Tags", provision[1]];
  declarations.push([path, 1, {value: 1}, null, {value: [provision[2]]}]);

  return true;
}


function reboot(sessionContext, provision, declarations, startRevision, endRevision) {
  declarations.push([["Reboot"], 1, {value: 1}, null, {value: [sessionContext.timestamp]}]);

  return true;
}


function reset(sessionContext, provision, declarations, startRevision, endRevision) {
  declarations.push([["FactoryReset"], 1, {value: 1}, null, {value: [sessionContext.timestamp]}]);

  return true;
}


function download(sessionContext, provision, declarations, startRevision, endRevision) {
  let alias = ["FileType", provision[1] || "", "FileName", provision[2] || "",
    "TargetFileName", provision[3] || ""];

  declarations.push([["Downloads", alias], 1, {}, 1]);
  declarations.push([["Downloads", alias, "Download"], 1, {value: 1}, null,
    {value: [sessionContext.timestamp]}]);

  return true;
}


function instances(sessionContext, provision, declarations, startRevision, endRevision) {
  let count = Number(provision[2]);

  if (Number.isNaN(count))
    return true;

  let path = common.parsePath(provision[1]);

  if (provision[2][0] === "+" || provision[2][0] === "-") {
    declarations.push([path, 1]);

    if (endRevision === startRevision)
      return false;

    let unpacked = device.unpack(sessionContext.deviceData, path, startRevision + 1);
    count = Math.max(0, unpacked.length + count);
  }

  declarations.push([path, 1, null, count]);

  return true;
}


exports.refresh = refresh;
exports.value = value;
exports.tag = tag;
exports.reboot = reboot;
exports.reset = reset;
exports.download = download;
exports.instances = instances;