// newAgent returns a new MachineAgent instance
func (s *commonMachineSuite) newAgent(c *gc.C, m *state.Machine) *MachineAgent {
	a := &MachineAgent{}
	s.initAgent(c, a, "--machine-id", m.Id())
	err := a.ReadConfig(m.Tag())
	c.Assert(err, gc.IsNil)
	return a
}

// waitRemoved waits for the supplied machine to be removed from state.
func (s *CommonProvisionerSuite) waitRemoved(c *gc.C, m *state.Machine) {
	s.waitMachine(c, m, func() bool {
		err := m.Refresh()
		if errors.IsNotFound(err) {
			return true
		}
		c.Assert(err, gc.IsNil)
		c.Logf("machine %v is still %s", m, m.Life())
		return false
	})
}

func (s *lxcProvisionerSuite) expectStarted(c *gc.C, machine *state.Machine) string {
	s.State.StartSync()
	event := <-s.events
	c.Assert(event.Action, gc.Equals, mock.Created)
	event = <-s.events
	c.Assert(event.Action, gc.Equals, mock.Started)
	err := machine.Refresh()
	c.Assert(err, gc.IsNil)
	s.waitInstanceId(c, machine, instance.Id(event.InstanceId))
	return event.InstanceId
}

// waitInstanceId waits until the supplied machine has an instance id, then
// asserts it is as expected.
func (s *CommonProvisionerSuite) waitInstanceId(c *gc.C, m *state.Machine, expect instance.Id) {
	s.waitHardwareCharacteristics(c, m, func() bool {
		if actual, err := m.InstanceId(); err == nil {
			c.Assert(actual, gc.Equals, expect)
			return true
		} else if !state.IsNotProvisionedError(err) {
			// We don't expect any errors.
			panic(err)
		}
		c.Logf("machine %v is still unprovisioned", m)
		return false
	})
}

func (s *CommonProvisionerSuite) checkStartInstanceCustom(c *gc.C, m *state.Machine, secret string, cons constraints.Value, includeNetworks, excludeNetworks []string, networkInfo []network.Info, waitInstanceId bool) (inst instance.Instance) {
	s.BackingState.StartSync()
	for {
		select {
		case o := <-s.op:
			switch o := o.(type) {
			case dummy.OpStartInstance:
				inst = o.Instance
				if waitInstanceId {
					s.waitInstanceId(c, m, inst.Id())
				}

				// Check the instance was started with the expected params.
				c.Assert(o.MachineId, gc.Equals, m.Id())
				nonceParts := strings.SplitN(o.MachineNonce, ":", 2)
				c.Assert(nonceParts, gc.HasLen, 2)
				c.Assert(nonceParts[0], gc.Equals, names.MachineTag("0"))
				c.Assert(nonceParts[1], jc.Satisfies, utils.IsValidUUIDString)
				c.Assert(o.Secret, gc.Equals, secret)
				c.Assert(o.IncludeNetworks, jc.DeepEquals, includeNetworks)
				c.Assert(o.ExcludeNetworks, jc.DeepEquals, excludeNetworks)
				c.Assert(o.NetworkInfo, jc.DeepEquals, networkInfo)

				// All provisioned machines in this test suite have
				// their hardware characteristics attributes set to
				// the same values as the constraints due to the dummy
				// environment being used.
				if !constraints.IsEmpty(&cons) {
					c.Assert(o.Constraints, gc.DeepEquals, cons)
					hc, err := m.HardwareCharacteristics()
					c.Assert(err, gc.IsNil)
					c.Assert(*hc, gc.DeepEquals, instance.HardwareCharacteristics{
						Arch:     cons.Arch,
						Mem:      cons.Mem,
						RootDisk: cons.RootDisk,
						CpuCores: cons.CpuCores,
						CpuPower: cons.CpuPower,
						Tags:     cons.Tags,
					})
				}
				return
			default:
				c.Logf("ignoring unexpected operation %#v", o)
			}
		case <-time.After(2 * time.Second):
			c.Fatalf("provisioner did not start an instance")
			return
		}
	}
	return
}

func (s *commonMachineSuite) setFakeMachineAddresses(c *gc.C, machine *state.Machine) {
	addrs := []instance.Address{
		instance.NewAddress("0.1.2.3", instance.NetworkUnknown),
	}
	err := machine.SetAddresses(addrs...)
	c.Assert(err, gc.IsNil)
	// Set the addresses in the environ instance as well so that if the instance poller
	// runs it won't overwrite them.
	instId, err := machine.InstanceId()
	c.Assert(err, gc.IsNil)
	insts, err := s.Conn.Environ.Instances([]instance.Id{instId})
	c.Assert(err, gc.IsNil)
	dummy.SetInstanceAddresses(insts[0], addrs)
}

func newMachineToolWaiter(m *state.Machine) *toolsWaiter {
	w := m.Watch()
	waiter := &toolsWaiter{
		changes: make(chan struct{}, 1),
		watcher: w,
		tooler:  m,
	}
	go func() {
		for _ = range w.Changes() {
			waiter.changes <- struct{}{}
		}
		close(waiter.changes)
	}()
	return waiter
}

func (t *LiveTests) assertStartInstance(c *gc.C, m *state.Machine) {
	// Wait for machine to get an instance id.
	for a := waitAgent.Start(); a.Next(); {
		err := m.Refresh()
		c.Assert(err, gc.IsNil)
		instId, err := m.InstanceId()
		if err != nil {
			c.Assert(err, jc.Satisfies, state.IsNotProvisionedError)
			continue
		}
		_, err = t.Env.Instances([]instance.Id{instId})
		c.Assert(err, gc.IsNil)
		return
	}
	c.Fatalf("provisioner failed to start machine after %v", waitAgent.Total)
}

func (s *CommonProvisionerSuite) waitHardwareCharacteristics(c *gc.C, m *state.Machine, check func() bool) {
	w := m.WatchHardwareCharacteristics()
	defer stop(c, w)
	timeout := time.After(coretesting.LongWait)
	resync := time.After(0)
	for {
		select {
		case <-w.Changes():
			if check() {
				return
			}
		case <-resync:
			resync = time.After(coretesting.ShortWait)
			s.BackingState.StartSync()
		case <-timeout:
			c.Fatalf("hardware characteristics for machine %v wait timed out", m)
		}
	}
}

// assertInstanceId asserts that the machine has an instance id
// that matches that of the given instance. If the instance is nil,
// It asserts that the instance id is unset.
func assertInstanceId(c *gc.C, m *state.Machine, inst instance.Instance) {
	var wantId, gotId instance.Id
	var err error
	if inst != nil {
		wantId = inst.Id()
	}
	for a := waitAgent.Start(); a.Next(); {
		err := m.Refresh()
		c.Assert(err, gc.IsNil)
		gotId, err = m.InstanceId()
		if err != nil {
			c.Assert(err, jc.Satisfies, state.IsNotProvisionedError)
			if inst == nil {
				return
			}
			continue
		}
		break
	}
	c.Assert(err, gc.IsNil)
	c.Assert(gotId, gc.Equals, wantId)
}

func (s *CommonProvisionerSuite) APILogin(c *gc.C, machine *state.Machine) {
	if s.st != nil {
		c.Assert(s.st.Close(), gc.IsNil)
	}
	password, err := utils.RandomPassword()
	c.Assert(err, gc.IsNil)
	err = machine.SetPassword(password)
	c.Assert(err, gc.IsNil)
	err = machine.SetProvisioned("i-fake", "fake_nonce", nil)
	c.Assert(err, gc.IsNil)
	s.st = s.OpenAPIAsMachine(c, machine.Tag(), password, "fake_nonce")
	c.Assert(s.st, gc.NotNil)
	c.Logf("API: login as %q successful", machine.Tag())
	s.provisioner = s.st.Provisioner()
	c.Assert(s.provisioner, gc.NotNil)
}

func (s *CommonProvisionerSuite) waitMachine(c *gc.C, m *state.Machine, check func() bool) {
	// TODO(jam): We need to grow a new method on NotifyWatcherC
	// that calls StartSync while waiting for changes, then
	// waitMachine and waitHardwareCharacteristics can use that
	// instead
	w := m.Watch()
	defer stop(c, w)
	timeout := time.After(coretesting.LongWait)
	resync := time.After(0)
	for {
		select {
		case <-w.Changes():
			if check() {
				return
			}
		case <-resync:
			resync = time.After(coretesting.ShortWait)
			s.BackingState.StartSync()
		case <-timeout:
			c.Fatalf("machine %v wait timed out", m)
		}
	}
}

// startInstance starts a new instance for the given machine.
func (s *FirewallerSuite) startInstance(c *gc.C, m *state.Machine) instance.Instance {
	inst, hc := testing.AssertStartInstance(c, s.Conn.Environ, m.Id())
	err := m.SetProvisioned(inst.Id(), "fake_nonce", hc)
	c.Assert(err, gc.IsNil)
	return inst
}

func (s *SSHCommonSuite) setAddresses(m *state.Machine, c *gc.C) {
	addrPub := instance.NewAddress(fmt.Sprintf("dummyenv-%s.dns", m.Id()), instance.NetworkPublic)
	addrPriv := instance.NewAddress(fmt.Sprintf("dummyenv-%s.internal", m.Id()), instance.NetworkCloudLocal)
	err := m.SetAddresses(addrPub, addrPriv)
	c.Assert(err, gc.IsNil)
}

// Run initializes state for an environment.
func (c *BootstrapCommand) Run(_ *cmd.Context) error {
	envCfg, err := config.New(config.NoDefaults, c.EnvConfig)
	if err != nil {
		return err
	}
	err = c.ReadConfig("machine-0")
	if err != nil {
		return err
	}
	agentConfig := c.CurrentConfig()

	// agent.Jobs is an optional field in the agent config, and was
	// introduced after 1.17.2. We default to allowing units on
	// machine-0 if missing.
	jobs := agentConfig.Jobs()
	if len(jobs) == 0 {
		jobs = []params.MachineJob{
			params.JobManageEnviron,
			params.JobHostUnits,
		}
	}

	// Get the bootstrap machine's addresses from the provider.
	env, err := environs.New(envCfg)
	if err != nil {
		return err
	}
	instanceId := instance.Id(c.InstanceId)
	instances, err := env.Instances([]instance.Id{instanceId})
	if err != nil {
		return err
	}
	addrs, err := instances[0].Addresses()
	if err != nil {
		return err
	}

	// Create system-identity file
	if err := agent.WriteSystemIdentityFile(agentConfig); err != nil {
		return err
	}

	// Generate a shared secret for the Mongo replica set, and write it out.
	sharedSecret, err := mongo.GenerateSharedSecret()
	if err != nil {
		return err
	}
	info, ok := agentConfig.StateServingInfo()
	if !ok {
		return fmt.Errorf("bootstrap machine config has no state serving info")
	}
	info.SharedSecret = sharedSecret
	err = c.ChangeConfig(func(agentConfig agent.ConfigSetter) {
		agentConfig.SetStateServingInfo(info)
	})
	if err != nil {
		return fmt.Errorf("cannot write agent config: %v", err)
	}
	agentConfig = c.CurrentConfig()

	if err := c.startMongo(addrs, agentConfig); err != nil {
		return err
	}

	logger.Infof("started mongo")
	// Initialise state, and store any agent config (e.g. password) changes.
	var st *state.State
	var m *state.Machine
	err = nil
	writeErr := c.ChangeConfig(func(agentConfig agent.ConfigSetter) {
		st, m, err = agent.InitializeState(
			agentConfig,
			envCfg,
			agent.BootstrapMachineConfig{
				Addresses:       addrs,
				Constraints:     c.Constraints,
				Jobs:            jobs,
				InstanceId:      instanceId,
				Characteristics: c.Hardware,
				SharedSecret:    sharedSecret,
			},
			state.DefaultDialOpts(),
			environs.NewStatePolicy(),
		)
	})
	if writeErr != nil {
		return fmt.Errorf("cannot write initial configuration: %v", err)
	}
	if err != nil {
		return err
	}
	defer st.Close()

	// bootstrap machine always gets the vote
	return m.SetHasVote(true)
}