// For these tests we use a fake DBus daemon to verify powerMonitor module
// interaction with the system bus. This requires python-dbusmock installed and
// running (with the DBUS_SYSTEM_BUS_ADDRESS environment variable set).
// script/spec-runner.js will take care of spawning the fake DBus daemon and setting
// DBUS_SYSTEM_BUS_ADDRESS when python-dbusmock is installed.
//
// See https://pypi.python.org/pypi/python-dbusmock for more information about
// python-dbusmock.
const chai = require('chai');
const dirtyChai = require('dirty-chai');
const dbus = require('dbus-native');
const Promise = require('bluebird');

const { expect } = chai;
chai.use(dirtyChai);

const skip = process.platform !== 'linux' || !process.env.DBUS_SYSTEM_BUS_ADDRESS;

describe('powerMonitor', () => {
  let logindMock, dbusMockPowerMonitor, getCalls, emitSignal, reset;

  if (!skip) {
    before(async () => {
      const systemBus = dbus.systemBus();
      const loginService = systemBus.getService('org.freedesktop.login1');
      const getInterface = Promise.promisify(loginService.getInterface, { context: loginService });
      logindMock = await getInterface('/org/freedesktop/login1', 'org.freedesktop.DBus.Mock');
      getCalls = Promise.promisify(logindMock.GetCalls, { context: logindMock });
      emitSignal = Promise.promisify(logindMock.EmitSignal, { context: logindMock });
      reset = Promise.promisify(logindMock.Reset, { context: logindMock });
    });

    after(async () => {
      await reset();
    });
  }

  (skip ? describe.skip : describe)('when powerMonitor module is loaded with dbus mock', () => {
    function onceMethodCalled (done) {
      function cb () {
        logindMock.removeListener('MethodCalled', cb);
      }
      done();
      return cb;
    }

    before(done => {
      logindMock.on('MethodCalled', onceMethodCalled(done));
      // lazy load powerMonitor after we listen to MethodCalled mock signal
      dbusMockPowerMonitor = require('electron').remote.powerMonitor;
    });

    it('should call Inhibit to delay suspend', async () => {
      const calls = await getCalls();
      expect(calls).to.be.an('array').that.has.lengthOf(1);
      expect(calls[0].slice(1)).to.deep.equal([
        'Inhibit', [
          [[{ type: 's', child: [] }], ['sleep']],
          [[{ type: 's', child: [] }], ['electron']],
          [[{ type: 's', child: [] }], ['Application cleanup before suspend']],
          [[{ type: 's', child: [] }], ['delay']]
        ]
      ]);
    });

    describe('when PrepareForSleep(true) signal is sent by logind', () => {
      it('should emit "suspend" event', (done) => {
        dbusMockPowerMonitor.once('suspend', () => done());
        emitSignal('org.freedesktop.login1.Manager', 'PrepareForSleep',
          'b', [['b', true]]);
      });

      describe('when PrepareForSleep(false) signal is sent by logind', () => {
        it('should emit "resume" event', done => {
          dbusMockPowerMonitor.once('resume', () => done());
          emitSignal('org.freedesktop.login1.Manager', 'PrepareForSleep',
            'b', [['b', false]]);
        });

        it('should have called Inhibit again', async () => {
          const calls = await getCalls();
          expect(calls).to.be.an('array').that.has.lengthOf(2);
          expect(calls[1].slice(1)).to.deep.equal([
            'Inhibit', [
              [[{ type: 's', child: [] }], ['sleep']],
              [[{ type: 's', child: [] }], ['electron']],
              [[{ type: 's', child: [] }], ['Application cleanup before suspend']],
              [[{ type: 's', child: [] }], ['delay']]
            ]
          ]);
        });
      });
    });

    describe('when a listener is added to shutdown event', () => {
      before(async () => {
        const calls = await getCalls();
        expect(calls).to.be.an('array').that.has.lengthOf(2);
        dbusMockPowerMonitor.once('shutdown', () => { });
      });

      it('should call Inhibit to delay shutdown', async () => {
        const calls = await getCalls();
        expect(calls).to.be.an('array').that.has.lengthOf(3);
        expect(calls[2].slice(1)).to.deep.equal([
          'Inhibit', [
            [[{ type: 's', child: [] }], ['shutdown']],
            [[{ type: 's', child: [] }], ['electron']],
            [[{ type: 's', child: [] }], ['Ensure a clean shutdown']],
            [[{ type: 's', child: [] }], ['delay']]
          ]
        ]);
      });

      describe('when PrepareForShutdown(true) signal is sent by logind', () => {
        it('should emit "shutdown" event', done => {
          dbusMockPowerMonitor.once('shutdown', () => { done(); });
          emitSignal('org.freedesktop.login1.Manager', 'PrepareForShutdown',
            'b', [['b', true]]);
        });
      });
    });
  });

  describe('when powerMonitor module is loaded', () => {
    let powerMonitor;
    before(() => {
      powerMonitor = require('electron').remote.powerMonitor;
    });

    describe('powerMonitor.getSystemIdleState', () => {
      it('gets current system idle state', () => {
        // this function is not mocked out, so we can test the result's
        // form and type but not its value.
        const idleState = powerMonitor.getSystemIdleState(1);
        expect(idleState).to.be.a('string');
        const validIdleStates = [ 'active', 'idle', 'locked', 'unknown' ];
        expect(validIdleStates).to.include(idleState);
      });

      it('does not accept non positive integer threshold', () => {
        expect(() => {
          powerMonitor.getSystemIdleState(-1);
        }).to.throw(/must be greater than 0/);

        expect(() => {
          powerMonitor.getSystemIdleState(NaN);
        }).to.throw(/conversion failure/);

        expect(() => {
          powerMonitor.getSystemIdleState('a');
        }).to.throw(/conversion failure/);
      });
    });

    describe('powerMonitor.getSystemIdleTime', () => {
      it('notify current system idle time', () => {
        const idleTime = powerMonitor.getSystemIdleTime();
        expect(idleTime).to.be.at.least(0);
      });
    });
  });
});