// -*- Mode: Go; indent-tabs-mode: t -*-

/*
 * Copyright (C) 2018 Canonical Ltd
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 3 as
 * published by the Free Software Foundation.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

package ifacestate_test

import (
	"errors"
	"fmt"
	"io/ioutil"
	"os"
	"path/filepath"
	"strings"

	. "gopkg.in/check.v1"

	"github.com/snapcore/snapd/dirs"
	"github.com/snapcore/snapd/interfaces"
	"github.com/snapcore/snapd/interfaces/ifacetest"
	"github.com/snapcore/snapd/logger"
	"github.com/snapcore/snapd/osutil"
	"github.com/snapcore/snapd/overlord"
	"github.com/snapcore/snapd/overlord/ifacestate"
	"github.com/snapcore/snapd/overlord/snapstate"
	"github.com/snapcore/snapd/overlord/state"
	"github.com/snapcore/snapd/snap"
	"github.com/snapcore/snapd/snap/snaptest"
	"github.com/snapcore/snapd/timings"
)

type helpersSuite struct {
	st *state.State
}

var _ = Suite(&helpersSuite{})

func (s *helpersSuite) SetUpTest(c *C) {
	s.st = state.New(nil)
	dirs.SetRootDir(c.MkDir())
}

func (s *helpersSuite) TearDownTest(c *C) {
	dirs.SetRootDir("")
}

func (s *helpersSuite) TestIdentityMapper(c *C) {
	var m ifacestate.SnapMapper = &ifacestate.IdentityMapper{}

	// Nothing is altered.
	c.Assert(m.RemapSnapFromState("example"), Equals, "example")
	c.Assert(m.RemapSnapToState("example"), Equals, "example")
	c.Assert(m.RemapSnapFromRequest("example"), Equals, "example")

	c.Assert(m.SystemSnapName(), Equals, "unknown")
}

func (s *helpersSuite) TestCoreCoreSystemMapper(c *C) {
	var m ifacestate.SnapMapper = &ifacestate.CoreCoreSystemMapper{}

	// Snaps are not renamed when interacting with the state.
	c.Assert(m.RemapSnapFromState("core"), Equals, "core")
	c.Assert(m.RemapSnapToState("core"), Equals, "core")

	// The "core" snap is renamed to the "system" in API response
	// and back in the API requests.
	c.Assert(m.RemapSnapFromRequest("system"), Equals, "core")

	// Other snap names are unchanged.
	c.Assert(m.RemapSnapFromState("potato"), Equals, "potato")
	c.Assert(m.RemapSnapToState("potato"), Equals, "potato")
	c.Assert(m.RemapSnapFromRequest("potato"), Equals, "potato")

	c.Assert(m.SystemSnapName(), Equals, "core")
}

func (s *helpersSuite) TestCoreSnapdSystemMapper(c *C) {
	var m ifacestate.SnapMapper = &ifacestate.CoreSnapdSystemMapper{}

	// The "snapd" snap is renamed to the "core" in when saving the state
	// and back when loading the state.
	c.Assert(m.RemapSnapFromState("core"), Equals, "snapd")
	c.Assert(m.RemapSnapToState("snapd"), Equals, "core")

	// The "snapd" snap is renamed to the "system" in API response and back in
	// the API requests.
	c.Assert(m.RemapSnapFromRequest("system"), Equals, "snapd")

	// The "core" snap is also renamed to "snapd" in API requests, for
	// compatibility.
	c.Assert(m.RemapSnapFromRequest("core"), Equals, "snapd")

	// Other snap names are unchanged.
	c.Assert(m.RemapSnapFromState("potato"), Equals, "potato")
	c.Assert(m.RemapSnapToState("potato"), Equals, "potato")
	c.Assert(m.RemapSnapFromRequest("potato"), Equals, "potato")

	c.Assert(m.SystemSnapName(), Equals, "snapd")
}

// caseMapper implements SnapMapper to use upper case internally and lower case externally.
type caseMapper struct{}

func (m *caseMapper) RemapSnapFromState(snapName string) string {
	return strings.ToUpper(snapName)
}

func (m *caseMapper) RemapSnapToState(snapName string) string {
	return strings.ToLower(snapName)
}

func (m *caseMapper) RemapSnapFromRequest(snapName string) string {
	return strings.ToUpper(snapName)
}

func (m *caseMapper) SystemSnapName() string {
	return "unknown"
}

func (s *helpersSuite) TestMappingFunctions(c *C) {
	restore := ifacestate.MockSnapMapper(&caseMapper{})
	defer restore()

	c.Assert(ifacestate.RemapSnapFromState("example"), Equals, "EXAMPLE")
	c.Assert(ifacestate.RemapSnapToState("EXAMPLE"), Equals, "example")
	c.Assert(ifacestate.RemapSnapFromRequest("example"), Equals, "EXAMPLE")
	c.Assert(ifacestate.SystemSnapName(), Equals, "unknown")
}

func (s *helpersSuite) TestGetConns(c *C) {
	s.st.Lock()
	defer s.st.Unlock()
	s.st.Set("conns", map[string]interface{}{
		"app:network core:network": map[string]interface{}{
			"auto":      true,
			"interface": "network",
			"slot-static": map[string]interface{}{
				"number": int(78),
			},
		},
	})

	restore := ifacestate.MockSnapMapper(&caseMapper{})
	defer restore()

	conns, err := ifacestate.GetConns(s.st)
	c.Assert(err, IsNil)
	for id, connState := range conns {
		c.Assert(id, Equals, "APP:network CORE:network")
		c.Assert(connState.Auto, Equals, true)
		c.Assert(connState.Interface, Equals, "network")
		c.Assert(connState.StaticSlotAttrs["number"], Equals, int64(78))
	}
}

func (s *helpersSuite) TestSetConns(c *C) {
	s.st.Lock()
	defer s.st.Unlock()

	restore := ifacestate.MockSnapMapper(&caseMapper{})
	defer restore()

	// This has upper-case data internally, see export_test.go
	ifacestate.SetConns(s.st, ifacestate.UpperCaseConnState())
	var conns map[string]interface{}
	err := s.st.Get("conns", &conns)
	c.Assert(err, IsNil)
	c.Assert(conns, DeepEquals, map[string]interface{}{
		"app:network core:network": map[string]interface{}{
			"auto":      true,
			"interface": "network",
		}})
}

func (s *helpersSuite) TestHotplugTaskHelpers(c *C) {
	s.st.Lock()
	defer s.st.Unlock()

	t := s.st.NewTask("foo", "")
	_, _, err := ifacestate.GetHotplugAttrs(t)
	c.Assert(err, ErrorMatches, `internal error: cannot get interface name from hotplug task: no state entry for key`)

	t.Set("interface", "x")
	_, _, err = ifacestate.GetHotplugAttrs(t)
	c.Assert(err, ErrorMatches, `internal error: cannot get hotplug key from hotplug task: no state entry for key`)

	ifacestate.SetHotplugAttrs(t, "iface", "key")

	var iface string
	var key snap.HotplugKey
	c.Assert(t.Get("hotplug-key", &key), IsNil)
	c.Assert(key, DeepEquals, snap.HotplugKey("key"))

	c.Assert(t.Get("interface", &iface), IsNil)
	c.Assert(iface, Equals, "iface")

	iface, key, err = ifacestate.GetHotplugAttrs(t)
	c.Assert(err, IsNil)
	c.Assert(key, DeepEquals, snap.HotplugKey("key"))
	c.Assert(iface, Equals, "iface")
}

func (s *helpersSuite) TestHotplugSlotInfo(c *C) {
	s.st.Lock()
	defer s.st.Unlock()

	slots, err := ifacestate.GetHotplugSlots(s.st)
	c.Assert(err, IsNil)
	c.Assert(slots, HasLen, 0)

	defs := map[string]*ifacestate.HotplugSlotInfo{}
	defs["foo"] = &ifacestate.HotplugSlotInfo{
		Name:        "foo",
		Interface:   "iface",
		StaticAttrs: map[string]interface{}{"attr": "value"},
		HotplugKey:  "key",
	}
	ifacestate.SetHotplugSlots(s.st, defs)

	var data map[string]interface{}
	c.Assert(s.st.Get("hotplug-slots", &data), IsNil)
	c.Assert(data, DeepEquals, map[string]interface{}{
		"foo": map[string]interface{}{
			"name":         "foo",
			"interface":    "iface",
			"static-attrs": map[string]interface{}{"attr": "value"},
			"hotplug-key":  "key",
			"hotplug-gone": false,
		}})

	slots, err = ifacestate.GetHotplugSlots(s.st)
	c.Assert(err, IsNil)
	c.Assert(slots, DeepEquals, defs)
}

func (s *helpersSuite) TestFindConnsForHotplugKey(c *C) {
	st := s.st
	st.Lock()
	defer st.Unlock()

	// Set conns in the state and get them via GetConns to avoid having to
	// know the internals of connState struct.
	st.Set("conns", map[string]interface{}{
		"snap1:plug1 core:slot1": map[string]interface{}{
			"interface":   "iface1",
			"hotplug-key": "key1",
		},
		"snap1:plug2 core:slot2": map[string]interface{}{
			"interface":   "iface2",
			"hotplug-key": "key1",
		},
		"snap1:plug3 core:slot3": map[string]interface{}{
			"interface":   "iface2",
			"hotplug-key": "key2",
		},
		"snap2:plug1 core:slot1": map[string]interface{}{
			"interface":   "iface2",
			"hotplug-key": "key2",
		},
	})

	conns, err := ifacestate.GetConns(st)
	c.Assert(err, IsNil)

	hotplugConns := ifacestate.FindConnsForHotplugKey(conns, "iface1", "key1")
	c.Assert(hotplugConns, DeepEquals, []string{"snap1:plug1 core:slot1"})

	hotplugConns = ifacestate.FindConnsForHotplugKey(conns, "iface2", "key2")
	c.Assert(hotplugConns, DeepEquals, []string{"snap1:plug3 core:slot3", "snap2:plug1 core:slot1"})

	hotplugConns = ifacestate.FindConnsForHotplugKey(conns, "unknown", "key1")
	c.Assert(hotplugConns, HasLen, 0)
}

func (s *helpersSuite) TestCheckIsSystemSnapPresentWithCore(c *C) {
	restore := ifacestate.MockSnapMapper(&ifacestate.CoreCoreSystemMapper{})
	defer restore()

	// no core snap yet
	c.Assert(ifacestate.CheckSystemSnapIsPresent(s.st), Equals, false)

	s.st.Lock()

	// add "core" snap
	sideInfo := &snap.SideInfo{Revision: snap.R(1)}
	snapInfo := snaptest.MockSnapInstance(c, "", coreSnapYaml, sideInfo)
	sideInfo.RealName = snapInfo.SnapName()

	snapstate.Set(s.st, snapInfo.InstanceName(), &snapstate.SnapState{
		Active:      true,
		Sequence:    []*snap.SideInfo{sideInfo},
		Current:     sideInfo.Revision,
		SnapType:    string(snapInfo.Type()),
		InstanceKey: snapInfo.InstanceKey,
	})
	s.st.Unlock()

	c.Assert(ifacestate.CheckSystemSnapIsPresent(s.st), Equals, true)
}

var snapdYaml = `name: snapd
version: 1.0
`

func (s *helpersSuite) TestCheckIsSystemSnapPresentWithSnapd(c *C) {
	restore := ifacestate.MockSnapMapper(&ifacestate.CoreSnapdSystemMapper{})
	defer restore()

	// no snapd snap yet
	c.Assert(ifacestate.CheckSystemSnapIsPresent(s.st), Equals, false)

	s.st.Lock()

	// "snapd" snap
	sideInfo := &snap.SideInfo{Revision: snap.R(1)}
	snapInfo := snaptest.MockSnapInstance(c, "", snapdYaml, sideInfo)
	sideInfo.RealName = snapInfo.SnapName()

	snapstate.Set(s.st, snapInfo.InstanceName(), &snapstate.SnapState{
		Active:      true,
		Sequence:    []*snap.SideInfo{sideInfo},
		Current:     sideInfo.Revision,
		SnapType:    string(snapInfo.Type()),
		InstanceKey: snapInfo.InstanceKey,
	})

	inf, err := ifacestate.SystemSnapInfo(s.st)
	c.Assert(err, IsNil)
	c.Assert(inf.InstanceName(), Equals, "snapd")

	s.st.Unlock()

	c.Assert(ifacestate.CheckSystemSnapIsPresent(s.st), Equals, true)
}

// Check what happens with system-key when security profile regeneration fails.
func (s *helpersSuite) TestSystemKeyAndFailingProfileRegeneration(c *C) {
	dirs.SetRootDir(c.MkDir())
	defer dirs.SetRootDir("")

	// Create a fake security backend with failing Setup method and mock all
	// security backends away so that we only use this special one. Note that
	// the backend is given a non-empty name as the interface manager skips
	// test backends with empty name for convenience.
	backend := &ifacetest.TestSecurityBackend{
		BackendName: "BROKEN",
		SetupCallback: func(snapInfo *snap.Info, opts interfaces.ConfinementOptions, repo *interfaces.Repository) error {
			return errors.New("FAILED")
		},
	}
	restore := ifacestate.MockSecurityBackends([]interfaces.SecurityBackend{backend})
	defer restore()

	// Create a mock overlord, mainly to have state.
	ovld := overlord.Mock()
	st := ovld.State()

	// Put a fake snap in the state, we need to setup security for at least one
	// snap to give the fake security backend a chance to fail.
	yamlText := `
name: test-snapd-canary
version: 1
apps:
  test-snapd-canary:
    command: bin/canary
`
	si := &snap.SideInfo{Revision: snap.R(1), RealName: "test-snapd-canary"}
	snapInfo := snaptest.MockSnap(c, yamlText, si)
	st.Lock()
	snapst := &snapstate.SnapState{
		SnapType: string(snap.TypeApp),
		Sequence: []*snap.SideInfo{si},
		Active:   true,
		Current:  snap.R(1),
	}
	snapstate.Set(st, snapInfo.InstanceName(), snapst)
	st.Unlock()

	// Pretend that security profiles are out of date and mock the
	// function that writes the new system key with one always panics.
	restore = ifacestate.MockProfilesNeedRegeneration(func() bool { return true })
	defer restore()
	restore = ifacestate.MockWriteSystemKey(func() error { panic("should not attempt to write system key") })
	defer restore()
	// Put a fake system key in place, we just want to see that file being removed.
	err := os.MkdirAll(filepath.Dir(dirs.SnapSystemKeyFile), 0755)
	c.Assert(err, IsNil)
	err = ioutil.WriteFile(dirs.SnapSystemKeyFile, []byte("system-key"), 0755)
	c.Assert(err, IsNil)

	// Put up a fake logger to capture logged messages.
	log, restore := logger.MockLogger()
	defer restore()

	// Construct and start up the interface manager.
	mgr, err := ifacestate.Manager(st, nil, ovld.TaskRunner(), nil, nil)
	c.Assert(err, IsNil)
	err = mgr.StartUp()
	c.Assert(err, IsNil)

	// Check that system key is not on disk.
	c.Check(log.String(), Matches, `.*cannot regenerate BROKEN profiles\n.*FAILED.*\n`)
	c.Check(osutil.FileExists(dirs.SnapSystemKeyFile), Equals, false)
}

func mockSnaps(c *C, st *state.State) {
	// Put fake snaps in the state
	for _, name := range []string{"foo", "bar"} {
		yamlText := `
name: %NAME%
version: 1
apps:
  test:
    command: bin/test
`
		si := &snap.SideInfo{Revision: snap.R(1), RealName: name}
		snapInfo := snaptest.MockSnap(c, strings.Replace(yamlText, "%NAME%", name, -1), si)
		st.Lock()
		snapst := &snapstate.SnapState{
			SnapType: string(snap.TypeApp),
			Sequence: []*snap.SideInfo{si},
			Active:   true,
			Current:  snap.R(1),
		}
		snapstate.Set(st, snapInfo.InstanceName(), snapst)
		st.Unlock()
	}
}

func (s *helpersSuite) TestProfileRegenerationSetupMany(c *C) {
	dirs.SetRootDir(c.MkDir())
	defer dirs.SetRootDir("")

	var setupManyCalls int
	var writeKey bool

	// Create a fake security backend
	backend := &ifacetest.TestSecurityBackendSetupMany{
		TestSecurityBackend: ifacetest.TestSecurityBackend{BackendName: "fake"},
		SetupManyCallback: func(snaps []*snap.Info, confinement func(snapName string) interfaces.ConfinementOptions, repo *interfaces.Repository, tm timings.Measurer) []error {
			c.Check(snaps, HasLen, 2)
			setupManyCalls++
			return nil
		},
	}
	restore := ifacestate.MockSecurityBackends([]interfaces.SecurityBackend{backend})
	defer restore()

	// Create a mock overlord, mainly to have state.
	ovld := overlord.Mock()
	st := ovld.State()

	mockSnaps(c, st)

	// Pretend that security profiles are out of date.
	restore = ifacestate.MockProfilesNeedRegeneration(func() bool { return true })
	defer restore()
	restore = ifacestate.MockWriteSystemKey(func() error {
		writeKey = true
		return nil
	})
	defer restore()

	// Construct and start up the interface manager.
	mgr, err := ifacestate.Manager(st, nil, ovld.TaskRunner(), nil, nil)
	c.Assert(err, IsNil)
	err = mgr.StartUp()
	c.Assert(err, IsNil)

	c.Check(writeKey, Equals, true)
	c.Check(setupManyCalls, Equals, 1)
}

func (s *helpersSuite) TestProfileRegenerationSetupManyFailsSystemKeyNotWritten(c *C) {
	dirs.SetRootDir(c.MkDir())
	defer dirs.SetRootDir("")

	var setupManyCalls int
	var writeKey bool

	// Create a fake security backend
	backend := &ifacetest.TestSecurityBackendSetupMany{
		TestSecurityBackend: ifacetest.TestSecurityBackend{BackendName: "fake"},
		SetupManyCallback: func(snaps []*snap.Info, confinement func(snapName string) interfaces.ConfinementOptions, repo *interfaces.Repository, tm timings.Measurer) []error {
			c.Check(snaps, HasLen, 2)
			setupManyCalls++
			return []error{fmt.Errorf("FAILED")}
		},
	}
	restore := ifacestate.MockSecurityBackends([]interfaces.SecurityBackend{backend})
	defer restore()

	// Put up a fake logger to capture logged messages.
	log, restoreLog := logger.MockLogger()
	defer restoreLog()

	// Create a mock overlord, mainly to have state.
	ovld := overlord.Mock()
	st := ovld.State()

	mockSnaps(c, st)

	// Pretend that security profiles are out of date.
	restore = ifacestate.MockProfilesNeedRegeneration(func() bool { return true })
	defer restore()
	restore = ifacestate.MockWriteSystemKey(func() error {
		writeKey = true
		return nil
	})
	defer restore()

	// Construct and start up the interface manager.
	mgr, err := ifacestate.Manager(st, nil, ovld.TaskRunner(), nil, nil)
	c.Assert(err, IsNil)
	err = mgr.StartUp()
	c.Assert(err, IsNil)

	// Check that system key is not on disk.
	c.Check(writeKey, Equals, false)
	c.Check(setupManyCalls, Equals, 1)
	c.Check(log.String(), Matches, ".*cannot regenerate fake profiles\n.*FAILED\n")
}

func (s *helpersSuite) TestIsHotplugChange(c *C) {
	s.st.Lock()
	defer s.st.Unlock()

	chg := s.st.NewChange("foo", "")
	c.Assert(ifacestate.IsHotplugChange(chg), Equals, false)

	chg = s.st.NewChange("hotplugfoo", "")
	c.Assert(ifacestate.IsHotplugChange(chg), Equals, false)

	chg = s.st.NewChange("hotplug-foo", "")
	c.Assert(ifacestate.IsHotplugChange(chg), Equals, true)
}

func (s *helpersSuite) TestGetHotplugChangeAttrs(c *C) {
	s.st.Lock()
	defer s.st.Unlock()

	chg := s.st.NewChange("none-set", "")
	_, _, err := ifacestate.GetHotplugChangeAttrs(chg)
	c.Assert(err, ErrorMatches, `internal error: hotplug-key not set on change "none-set"`)

	chg = s.st.NewChange("foo", "")
	chg.Set("hotplug-seq", 1)
	_, _, err = ifacestate.GetHotplugChangeAttrs(chg)
	c.Assert(err, ErrorMatches, `internal error: hotplug-key not set on change "foo"`)

	chg = s.st.NewChange("bar", "")
	chg.Set("hotplug-key", "2222")
	_, _, err = ifacestate.GetHotplugChangeAttrs(chg)
	c.Assert(err, ErrorMatches, `internal error: hotplug-seq not set on change "bar"`)

	chg = s.st.NewChange("baz", "")
	chg.Set("hotplug-key", "1234")
	chg.Set("hotplug-seq", 7)

	seq, key, err := ifacestate.GetHotplugChangeAttrs(chg)
	c.Assert(err, IsNil)
	c.Check(key, DeepEquals, snap.HotplugKey("1234"))
	c.Check(seq, Equals, 7)
}

func (s *helpersSuite) TestSetHotplugChangeAttrs(c *C) {
	s.st.Lock()
	defer s.st.Unlock()

	chg := s.st.NewChange("foo", "")
	ifacestate.SetHotplugChangeAttrs(chg, 12, "abcd")

	var seq int
	var hotplugKey string
	c.Assert(chg.Get("hotplug-seq", &seq), IsNil)
	c.Assert(chg.Get("hotplug-key", &hotplugKey), IsNil)
	c.Check(seq, Equals, 12)
	c.Check(hotplugKey, Equals, "abcd")
}

func (s *helpersSuite) TestAllocHotplugSeq(c *C) {
	s.st.Lock()
	defer s.st.Unlock()

	var stateSeq int

	// sanity
	c.Assert(s.st.Get("hotplug-seq", &stateSeq), Equals, state.ErrNoState)

	seq, err := ifacestate.AllocHotplugSeq(s.st)
	c.Assert(err, IsNil)
	c.Assert(seq, Equals, 1)

	seq, err = ifacestate.AllocHotplugSeq(s.st)
	c.Assert(err, IsNil)
	c.Assert(seq, Equals, 2)

	c.Assert(s.st.Get("hotplug-seq", &stateSeq), IsNil)
	c.Check(stateSeq, Equals, 2)
}

func (s *helpersSuite) TestAddHotplugSeqWaitTask(c *C) {
	s.st.Lock()
	defer s.st.Unlock()

	chg := s.st.NewChange("foo", "")
	t1 := s.st.NewTask("task1", "")
	t2 := s.st.NewTask("task2", "")
	chg.AddTask(t1)
	chg.AddTask(t2)

	ifacestate.AddHotplugSeqWaitTask(chg, "1234", 1)
	// hotplug change got an extra task
	c.Assert(chg.Tasks(), HasLen, 3)
	seq, key, err := ifacestate.GetHotplugChangeAttrs(chg)
	c.Assert(err, IsNil)
	c.Check(seq, Equals, 1)
	c.Check(key, DeepEquals, snap.HotplugKey("1234"))

	var seqTask *state.Task
	for _, t := range chg.Tasks() {
		if t.Kind() == "hotplug-seq-wait" {
			seqTask = t
			break
		}
	}
	c.Assert(seqTask, NotNil)

	// existing tasks wait for the hotplug-seq-wait task
	c.Assert(t1.WaitTasks(), HasLen, 1)
	c.Assert(t1.WaitTasks()[0].ID(), Equals, seqTask.ID())
	c.Assert(t2.WaitTasks(), HasLen, 1)
	c.Assert(t2.WaitTasks()[0].ID(), Equals, seqTask.ID())
}

func (s *helpersSuite) TestAddHotplugSlot(c *C) {
	s.st.Lock()
	defer s.st.Unlock()

	var beforePrepareSlotCalled int
	repo := interfaces.NewRepository()
	iface := &ifacetest.TestInterface{
		InterfaceName: "test",
		BeforePrepareSlotCallback: func(*snap.SlotInfo) error {
			beforePrepareSlotCalled += 1
			return nil
		},
	}
	repo.AddInterface(iface)

	stateSlots, err := ifacestate.GetHotplugSlots(s.st)
	c.Assert(err, IsNil)
	c.Check(stateSlots, HasLen, 0)

	si := &snap.SideInfo{Revision: snap.R(1)}
	coreInfo := snaptest.MockSnap(c, coreSnapYaml, si)

	slot := &snap.SlotInfo{
		Name:       "slot",
		Label:      "label",
		Snap:       coreInfo,
		Interface:  "test",
		Attrs:      map[string]interface{}{"foo": "bar"},
		HotplugKey: "key",
	}
	c.Assert(ifacestate.AddHotplugSlot(s.st, repo, stateSlots, iface, slot), IsNil)
	c.Assert(beforePrepareSlotCalled, Equals, 1)

	// same slot cannot be re-added to repo
	c.Assert(ifacestate.AddHotplugSlot(s.st, repo, stateSlots, iface, slot), ErrorMatches, `cannot add hotplug slot "slot" for interface test: snap "core" has slots conflicting on name "slot"`)

	stateSlots, err = ifacestate.GetHotplugSlots(s.st)
	c.Assert(err, IsNil)
	c.Assert(stateSlots, HasLen, 1)

	stateSlot := stateSlots["slot"]
	c.Assert(stateSlot, NotNil)
	c.Check(stateSlot, DeepEquals, &ifacestate.HotplugSlotInfo{
		Name:        "slot",
		Interface:   "test",
		StaticAttrs: map[string]interface{}{"foo": "bar"},
		HotplugKey:  "key",
		HotplugGone: false})
}

func (s *helpersSuite) TestAddHotplugSlotValidationErrors(c *C) {
	s.st.Lock()
	defer s.st.Unlock()

	repo := interfaces.NewRepository()
	iface := &ifacetest.TestInterface{
		InterfaceName:             "test",
		BeforePrepareSlotCallback: func(slot *snap.SlotInfo) error { return fmt.Errorf("fail") },
	}
	repo.AddInterface(iface)

	stateSlots, err := ifacestate.GetHotplugSlots(s.st)
	c.Assert(err, IsNil)
	c.Check(stateSlots, HasLen, 0)

	si := &snap.SideInfo{Revision: snap.R(1)}
	coreInfo := snaptest.MockSnap(c, coreSnapYaml, si)

	slot := &snap.SlotInfo{
		Name:      "slot",
		Snap:      coreInfo,
		Interface: "test",
	}
	// hotplug key missing
	c.Assert(ifacestate.AddHotplugSlot(s.st, repo, stateSlots, iface, slot), ErrorMatches, `internal error: cannot store slot "slot", not a hotplug slot`)
	slot.HotplugKey = "key"

	// sanitization failure
	c.Assert(ifacestate.AddHotplugSlot(s.st, repo, stateSlots, iface, slot), ErrorMatches, `cannot sanitize hotplug slot \"slot\" for interface test: fail`)
}

func (s *helpersSuite) TestDiscardLateBackendViaSnapstate(c *C) {
	s.st.Lock()
	defer s.st.Unlock()
	dirs.SetRootDir(c.MkDir())
	defer dirs.SetRootDir("")

	// security profiles do not need regeneration when crating the manager
	restore := ifacestate.MockProfilesNeedRegeneration(func() bool { return false })
	defer restore()

	backend := &ifacetest.TestSecurityBackendDiscardingLate{
		RemoveLateCallback: func(snapName string, rev snap.Revision, typ snap.Type) error {
			if snapName == "this-fails" {
				return fmt.Errorf("remove late fails")
			}
			return nil
		},
	}
	restore = ifacestate.MockSecurityBackends([]interfaces.SecurityBackend{backend})
	defer restore()

	// mock overlord
	ovld := overlord.Mock()
	st := ovld.State()
	// manager
	mgr, err := ifacestate.Manager(st, nil, ovld.TaskRunner(), nil, nil)
	c.Assert(err, IsNil)
	// installs the ifacemgr helper
	err = mgr.StartUp()
	c.Assert(err, IsNil)

	// call via the snapstate hook
	err = snapstate.SecurityProfilesRemoveLate("snapd", snap.R(1234), snap.TypeSnapd)
	c.Assert(err, IsNil)
	err = snapstate.SecurityProfilesRemoveLate("this-fails", snap.R(12), snap.TypeApp)
	c.Assert(err, ErrorMatches, "remove late fails")
	c.Check(backend.RemoveLateCalledFor, DeepEquals, [][]string{
		{"snapd", "1234", "snapd"},
		{"this-fails", "12", "app"},
	})
}
