Unbreak things

2 files changed, 460 insertions, 60 deletions

diff --git a/matrix/rooms/room.go b/matrix/rooms/room.go
index 717636b..87c3780 100644
--- a/matrix/rooms/room.go
+++ b/matrix/rooms/room.go
@@ -17,6 +17,7 @@
 package rooms
 
 import (
+	"compress/gzip"
 	"encoding/gob"
 	"fmt"
 	"os"
@@ -31,17 +32,20 @@ import (
 )
 
 func init() {
-	gob.Register([]interface{}{})
 	gob.Register(map[string]interface{}{})
+	gob.Register([]interface{}{})
+	gob.Register(&Room{})
+	gob.Register(0)
 }
 
 type RoomNameSource int
 
 const (
-	ExplicitRoomName RoomNameSource = iota
-	CanonicalAliasRoomName
-	AliasRoomName
+	UnknownRoomName RoomNameSource = iota
 	MemberRoomName
+	AliasRoomName
+	CanonicalAliasRoomName
+	ExplicitRoomName
 )
 
 // RoomTag is a tag given to a specific room.
@@ -60,7 +64,8 @@ type UnreadMessage struct {
 
 // Room represents a single Matrix room.
 type Room struct {
-	*mautrix.Room
+	// The room ID.
+	ID string
 
 	// Whether or not the user has left the room.
 	HasLeft bool
@@ -79,19 +84,22 @@ type Room struct {
 	// Whether or not this room is marked as a direct chat.
 	IsDirect bool
 
-	// List of tags given to this room
+	// List of tags given to this room.
 	RawTags []RoomTag
 	// Timestamp of previously received actual message.
 	LastReceivedMessage time.Time
 
+	// Room state cache.
+	state map[mautrix.EventType]map[string]*mautrix.Event
 	// MXID -> Member cache calculated from membership events.
 	memberCache map[string]*mautrix.Member
-	// The first non-SessionUserID member in the room. Calculated at
+	// The first two non-SessionUserID members in the room. Calculated at
 	// the same time as memberCache.
-	firstMemberCache *mautrix.Member
+	firstMemberCache  *mautrix.Member
+	secondMemberCache *mautrix.Member
 	// The name of the room. Calculated from the state event name,
 	// canonical_alias or alias or the member cache.
-	nameCache string
+	NameCache string
 	// The event type from which the name cache was calculated from.
 	nameCacheSource RoomNameSource
 	// The topic of the room. Directly fetched from the m.room.topic state event.
@@ -101,31 +109,98 @@ type Room struct {
 	// The list of aliases. Directly fetched from the m.room.aliases state event.
 	aliasesCache []string
 
+	// Path for state store file.
+	path string
+	// Room cache object
+	cache *RoomCache
+	// Lock for state and other room stuff.
 	lock sync.RWMutex
+
+	// Room state cache linked list.
+	prev  *Room
+	next  *Room
+	touch int64
 }
 
-func (room *Room) Load(path string) error {
-	file, err := os.OpenFile(path, os.O_RDONLY, 0600)
-	if err != nil {
-		return err
+func debugPrintError(fn func() error, message string) {
+	if err := fn(); err != nil {
+		debug.Printf("%s: %v", message, err)
+	}
+}
+
+func (room *Room) Loaded() bool {
+	return room.state != nil
+}
+
+func (room *Room) Load() {
+	if room.Loaded() {
+		return
 	}
-	defer file.Close()
-	dec := gob.NewDecoder(file)
+	room.cache.TouchNode(room)
 	room.lock.Lock()
-	defer room.lock.Unlock()
-	return dec.Decode(room)
+	room.load()
+	room.lock.Unlock()
 }
 
-func (room *Room) Save(path string) error {
-	file, err := os.OpenFile(path, os.O_WRONLY|os.O_CREATE, 0600)
+func (room *Room) load() {
+	if room.Loaded() {
+		return
+	}
+	debug.Print("Loading state for room", room.ID)
+	room.state = make(map[mautrix.EventType]map[string]*mautrix.Event)
+	file, err := os.OpenFile(room.path, os.O_RDONLY, 0600)
 	if err != nil {
-		return err
+		if !os.IsNotExist(err) {
+			debug.Print("Failed to open room state file for reading:", err)
+		} else {
+			debug.Print("Room state file for", room.ID, "does not exist")
+		}
+		return
 	}
-	defer file.Close()
-	enc := gob.NewEncoder(file)
+	defer debugPrintError(file.Close, "Failed to close room state file after reading")
+	cmpReader, err := gzip.NewReader(file)
+	if err != nil {
+		debug.Print("Failed to open room state gzip reader:", err)
+		return
+	}
+	defer debugPrintError(cmpReader.Close, "Failed to close room state gzip reader")
+	dec := gob.NewDecoder(cmpReader)
+	if err = dec.Decode(&room.state); err != nil {
+		debug.Print("Failed to decode room state:", err)
+	}
+}
+
+func (room *Room) Unload() {
+	debug.Print("Unloading", room.ID)
+	room.Save()
+	room.state = nil
+	room.aliasesCache = nil
+	room.topicCache = ""
+	room.canonicalAliasCache = ""
+	room.firstMemberCache = nil
+	room.secondMemberCache = nil
+}
+
+func (room *Room) Save() {
+	if !room.Loaded() {
+		debug.Print("Failed to save room state: room not loaded")
+		return
+	}
+	debug.Print("Saving state for room", room.ID)
+	file, err := os.OpenFile(room.path, os.O_WRONLY|os.O_CREATE, 0600)
+	if err != nil {
+		debug.Print("Failed to open room state file for writing:", err)
+		return
+	}
+	defer debugPrintError(file.Close, "Failed to close room state file after writing")
+	cmpWriter := gzip.NewWriter(file)
+	defer debugPrintError(cmpWriter.Close, "Failed to close room state gzip writer")
+	enc := gob.NewEncoder(cmpWriter)
 	room.lock.RLock()
 	defer room.lock.RUnlock()
-	return enc.Encode(room)
+	if err := enc.Encode(&room.state); err != nil {
+		debug.Print("Failed to encode room state:", err)
+	}
 }
 
 // MarkRead clears the new message statuses on this room.
@@ -220,30 +295,32 @@ func (room *Room) Tags() []RoomTag {
 // UpdateState updates the room's current state with the given Event. This will clobber events based
 // on the type/state_key combination.
 func (room *Room) UpdateState(event *mautrix.Event) {
+	room.Load()
 	room.lock.Lock()
 	defer room.lock.Unlock()
-	_, exists := room.State[event.Type]
+	_, exists := room.state[event.Type]
 	if !exists {
-		room.State[event.Type] = make(map[string]*mautrix.Event)
+		room.state[event.Type] = make(map[string]*mautrix.Event)
 	}
 	switch event.Type {
 	case mautrix.StateRoomName:
-		room.nameCache = ""
+		room.NameCache = ""
 	case mautrix.StateCanonicalAlias:
-		if room.nameCacheSource >= CanonicalAliasRoomName {
-			room.nameCache = ""
+		if room.nameCacheSource <= CanonicalAliasRoomName {
+			room.NameCache = ""
 		}
 		room.canonicalAliasCache = ""
 	case mautrix.StateAliases:
-		if room.nameCacheSource >= AliasRoomName {
-			room.nameCache = ""
+		if room.nameCacheSource <= AliasRoomName {
+			room.NameCache = ""
 		}
 		room.aliasesCache = nil
 	case mautrix.StateMember:
 		room.memberCache = nil
 		room.firstMemberCache = nil
-		if room.nameCacheSource >= MemberRoomName {
-			room.nameCache = ""
+		room.secondMemberCache = nil
+		if room.nameCacheSource <= MemberRoomName {
+			room.NameCache = ""
 		}
 	case mautrix.StateTopic:
 		room.topicCache = ""
@@ -258,24 +335,25 @@ func (room *Room) UpdateState(event *mautrix.Event) {
 	}
 
 	if event.StateKey == nil {
-		room.State[event.Type][""] = event
+		room.state[event.Type][""] = event
 	} else {
-		room.State[event.Type][*event.StateKey] = event
+		room.state[event.Type][*event.StateKey] = event
 	}
 }
 
 // GetStateEvent returns the state event for the given type/state_key combo, or nil.
 func (room *Room) GetStateEvent(eventType mautrix.EventType, stateKey string) *mautrix.Event {
+	room.Load()
 	room.lock.RLock()
 	defer room.lock.RUnlock()
-	stateEventMap, _ := room.State[eventType]
+	stateEventMap, _ := room.state[eventType]
 	event, _ := stateEventMap[stateKey]
 	return event
 }
 
 // getStateEvents returns the state events for the given type.
 func (room *Room) getStateEvents(eventType mautrix.EventType) map[string]*mautrix.Event {
-	stateEventMap, _ := room.State[eventType]
+	stateEventMap, _ := room.state[eventType]
 	return stateEventMap
 }
 
@@ -323,7 +401,7 @@ func (room *Room) GetAliases() []string {
 func (room *Room) updateNameFromNameEvent() {
 	nameEvt := room.GetStateEvent(mautrix.StateRoomName, "")
 	if nameEvt != nil {
-		room.nameCache = nameEvt.Content.Name
+		room.NameCache = nameEvt.Content.Name
 	}
 }
 
@@ -336,7 +414,7 @@ func (room *Room) updateNameFromAliases() {
 	aliases := room.GetAliases()
 	if len(aliases) > 0 {
 		sort.Sort(sort.StringSlice(aliases))
-		room.nameCache = aliases[0]
+		room.NameCache = aliases[0]
 	}
 }
 
@@ -351,33 +429,40 @@ func (room *Room) updateNameFromAliases() {
 func (room *Room) updateNameFromMembers() {
 	members := room.GetMembers()
 	if len(members) <= 1 {
-		room.nameCache = "Empty room"
+		room.NameCache = "Empty room"
 	} else if room.firstMemberCache == nil {
-		room.nameCache = "Room"
+		room.NameCache = "Room"
 	} else if len(members) == 2 {
-		room.nameCache = room.firstMemberCache.Displayname
+		room.NameCache = room.firstMemberCache.Displayname
+	} else if len(members) == 3 && room.secondMemberCache != nil {
+		room.NameCache = fmt.Sprintf("%s and %s", room.firstMemberCache.Displayname, room.secondMemberCache.Displayname)
 	} else {
-		firstMember := room.firstMemberCache.Displayname
-		room.nameCache = fmt.Sprintf("%s and %d others", firstMember, len(members)-2)
+		members := room.firstMemberCache.Displayname
+		count := len(members) - 2
+		if room.secondMemberCache != nil {
+			members += ", " + room.secondMemberCache.Displayname
+			count--
+		}
+		room.NameCache = fmt.Sprintf("%s and %d others", members, count)
 	}
 }
 
 // updateNameCache updates the room display name based on the room state in the order
 // specified in spec section 11.2.2.5.
 func (room *Room) updateNameCache() {
-	if len(room.nameCache) == 0 {
+	if len(room.NameCache) == 0 {
 		room.updateNameFromNameEvent()
 		room.nameCacheSource = ExplicitRoomName
 	}
-	if len(room.nameCache) == 0 {
-		room.nameCache = room.GetCanonicalAlias()
+	if len(room.NameCache) == 0 {
+		room.NameCache = room.GetCanonicalAlias()
 		room.nameCacheSource = CanonicalAliasRoomName
 	}
-	if len(room.nameCache) == 0 {
+	if len(room.NameCache) == 0 {
 		room.updateNameFromAliases()
 		room.nameCacheSource = AliasRoomName
 	}
-	if len(room.nameCache) == 0 {
+	if len(room.NameCache) == 0 {
 		room.updateNameFromMembers()
 		room.nameCacheSource = MemberRoomName
 	}
@@ -389,15 +474,19 @@ func (room *Room) updateNameCache() {
 // If the cache is empty, it is updated first.
 func (room *Room) GetTitle() string {
 	room.updateNameCache()
-	return room.nameCache
+	return room.NameCache
 }
 
 // createMemberCache caches all member events into a easily processable MXID -> *Member map.
 func (room *Room) createMemberCache() map[string]*mautrix.Member {
+	if len(room.memberCache) > 0 {
+		return room.memberCache
+	}
 	cache := make(map[string]*mautrix.Member)
 	room.lock.RLock()
 	events := room.getStateEvents(mautrix.StateMember)
 	room.firstMemberCache = nil
+	room.secondMemberCache = nil
 	if events != nil {
 		for userID, event := range events {
 			member := &event.Content.Member
@@ -405,8 +494,12 @@ func (room *Room) createMemberCache() map[string]*mautrix.Member {
 			if len(member.Displayname) == 0 {
 				member.Displayname = userID
 			}
-			if room.firstMemberCache == nil && userID != room.SessionUserID {
-				room.firstMemberCache = member
+			if userID != room.SessionUserID {
+				if room.firstMemberCache == nil {
+					room.firstMemberCache = member
+				} else if room.secondMemberCache == nil {
+					room.secondMemberCache = member
+				}
 			}
 			if member.Membership == mautrix.MembershipJoin || member.Membership == mautrix.MembershipInvite {
 				cache[userID] = member
@@ -425,18 +518,16 @@ func (room *Room) createMemberCache() map[string]*mautrix.Member {
 // The members are returned from the cache.
 // If the cache is empty, it is updated first.
 func (room *Room) GetMembers() map[string]*mautrix.Member {
-	if len(room.memberCache) == 0 || room.firstMemberCache == nil {
-		room.createMemberCache()
-	}
+	room.Load()
+	room.createMemberCache()
 	return room.memberCache
 }
 
 // GetMember returns the member with the given MXID.
 // If the member doesn't exist, nil is returned.
 func (room *Room) GetMember(userID string) *mautrix.Member {
-	if len(room.memberCache) == 0 {
-		room.createMemberCache()
-	}
+	room.Load()
+	room.createMemberCache()
 	room.lock.RLock()
 	member, _ := room.memberCache[userID]
 	room.lock.RUnlock()
@@ -449,9 +540,13 @@ func (room *Room) GetSessionOwner() string {
 }
 
 // NewRoom creates a new Room with the given ID
-func NewRoom(roomID, owner string) *Room {
+func NewRoom(roomID string, cache *RoomCache) *Room {
 	return &Room{
-		Room:          mautrix.NewRoom(roomID),
-		SessionUserID: owner,
+		ID:    roomID,
+		state: make(map[mautrix.EventType]map[string]*mautrix.Event),
+		path:  cache.roomPath(roomID),
+		cache: cache,
+
+		SessionUserID: cache.getOwner(),
 	}
 }
diff --git a/matrix/rooms/roomcache.go b/matrix/rooms/roomcache.go
new file mode 100644
index 0000000..03e3ad8
--- /dev/null
+++ b/matrix/rooms/roomcache.go
@@ -0,0 +1,305 @@
+// gomuks - A terminal Matrix client written in Go.
+// Copyright (C) 2019 Tulir Asokan
+//
+// This program 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.
+//
+// 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 Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+package rooms
+
+import (
+	"compress/gzip"
+	"encoding/gob"
+	"os"
+	"path/filepath"
+	"time"
+
+	"github.com/pkg/errors"
+	sync "github.com/sasha-s/go-deadlock"
+
+	"maunium.net/go/gomuks/debug"
+)
+
+// RoomCache contains room state info in a hashmap and linked list.
+type RoomCache struct {
+	sync.Mutex
+
+	listPath  string
+	directory string
+	maxSize   int
+	maxAge    int64
+	getOwner  func() string
+
+	Map  map[string]*Room
+	head *Room
+	tail *Room
+	size int
+}
+
+func NewRoomCache(listPath, directory string, maxSize int, maxAge int64, getOwner func() string) *RoomCache {
+	return &RoomCache{
+		listPath:  listPath,
+		directory: directory,
+		maxSize:   maxSize,
+		maxAge:    maxAge,
+		getOwner:  getOwner,
+
+		Map: make(map[string]*Room),
+	}
+}
+
+func (cache *RoomCache) LoadList() error {
+	cache.Lock()
+	defer cache.Unlock()
+
+	// Open room list file
+	file, err := os.OpenFile(cache.listPath, os.O_RDONLY, 0600)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return nil
+		}
+		return errors.Wrap(err, "failed to open room list file for reading")
+	}
+	defer debugPrintError(file.Close, "Failed to close room list file after reading")
+
+	// Open gzip reader for room list file
+	cmpReader, err := gzip.NewReader(file)
+	if err != nil {
+		return errors.Wrap(err, "failed to read gzip room list")
+	}
+	defer debugPrintError(cmpReader.Close, "Failed to close room list gzip reader")
+
+	// Open gob decoder for gzip reader
+	dec := gob.NewDecoder(cmpReader)
+	// Read number of items in list
+	var size int
+	err = dec.Decode(&size)
+	if err != nil {
+		return errors.Wrap(err, "failed to read size of room list")
+	}
+
+	// Read list
+	cache.Map = make(map[string]*Room, size)
+	for i := 0; i < size; i++ {
+		room := &Room{}
+		err = dec.Decode(room)
+		if err != nil {
+			debug.Printf("Failed to decode %dth room list entry: %v", i+1, err)
+			continue
+		}
+		room.path = cache.roomPath(room.ID)
+		room.cache = cache
+		cache.Map[room.ID] = room
+	}
+	return nil
+}
+
+func (cache *RoomCache) SaveLoadedRooms() {
+	cache.Lock()
+	defer cache.Unlock()
+	cache.clean()
+	for node := cache.head; node != nil; node = node.prev {
+		node.Save()
+	}
+}
+
+func (cache *RoomCache) SaveList() error {
+	cache.Lock()
+	defer cache.Unlock()
+
+	debug.Print("Saving room list...")
+	// Open room list file
+	file, err := os.OpenFile(cache.listPath, os.O_WRONLY|os.O_CREATE, 0600)
+	if err != nil {
+		return errors.Wrap(err, "failed to open room list file for writing")
+	}
+	defer debugPrintError(file.Close, "Failed to close room list file after writing")
+
+	// Open gzip writer for room list file
+	cmpWriter := gzip.NewWriter(file)
+	defer debugPrintError(cmpWriter.Close, "Failed to close room list gzip writer")
+
+	// Open gob encoder for gzip writer
+	enc := gob.NewEncoder(cmpWriter)
+	// Write number of items in list
+	err = enc.Encode(len(cache.Map))
+	if err != nil {
+		return errors.Wrap(err, "failed to write size of room list")
+	}
+
+	// Write list
+	for _, node := range cache.Map {
+		err = enc.Encode(node)
+		if err != nil {
+			debug.Printf("Failed to encode room list entry of %s: %v", node.ID, err)
+		}
+	}
+	debug.Print("Room list saved to", cache.listPath, len(cache.Map), cache.size)
+	return nil
+}
+
+func (cache *RoomCache) Touch(roomID string) {
+	cache.Lock()
+	node, ok := cache.Map[roomID]
+	if !ok || node == nil {
+		cache.Unlock()
+		return
+	}
+	cache.touch(node)
+	cache.Unlock()
+}
+
+func (cache *RoomCache) TouchNode(node *Room) {
+	cache.Lock()
+	cache.touch(node)
+	cache.Unlock()
+}
+
+func (cache *RoomCache) touch(node *Room) {
+	if node == cache.head {
+		return
+	}
+	debug.Print("Touching", node.ID)
+	cache.llPop(node)
+	cache.llPush(node)
+	node.touch = time.Now().Unix()
+}
+
+func (cache *RoomCache) Get(roomID string) *Room {
+	cache.Lock()
+	node := cache.get(roomID)
+	cache.Unlock()
+	return node
+}
+
+func (cache *RoomCache) GetOrCreate(roomID string) *Room {
+	cache.Lock()
+	node := cache.get(roomID)
+	if node == nil {
+		node = cache.newRoom(roomID)
+		cache.llPush(node)
+	}
+	cache.Unlock()
+	return node
+}
+
+func (cache *RoomCache) get(roomID string) *Room {
+	node, ok := cache.Map[roomID]
+	if ok && node != nil && node.Loaded() {
+		cache.touch(node)
+		return node
+	}
+	return nil
+}
+func (cache *RoomCache) Put(room *Room) {
+	cache.Lock()
+	node := cache.get(room.ID)
+	if node != nil {
+		cache.touch(node)
+	} else {
+		cache.Map[room.ID] = room
+		if room.Loaded() {
+			cache.llPush(room)
+		}
+		node = room
+	}
+	cache.Unlock()
+	node.Save()
+}
+
+func (cache *RoomCache) roomPath(roomID string) string {
+	return filepath.Join(cache.directory, roomID+".gob.gz")
+}
+
+func (cache *RoomCache) Load(roomID string) *Room {
+	cache.Lock()
+	defer cache.Unlock()
+	node, ok := cache.Map[roomID]
+	if ok {
+		return node
+	}
+
+	node = NewRoom(roomID, cache)
+	node.Load()
+	return node
+}
+
+func (cache *RoomCache) llPop(node *Room) {
+	if node.prev == nil && node.next == nil {
+		return
+	}
+	if node.prev != nil {
+		node.prev.next = node.next
+	}
+	if node.next != nil {
+		node.next.prev = node.prev
+	}
+	if node == cache.tail {
+		cache.tail = node.next
+	}
+	if node == cache.head {
+		cache.head = node.prev
+	}
+	node.next = nil
+	node.prev = nil
+	cache.size--
+}
+
+func (cache *RoomCache) llPush(node *Room) {
+	if node.next != nil || node.prev != nil {
+		debug.PrintStack()
+		debug.Print("Tried to llPush node that is already in stack")
+		return
+	}
+	if node == cache.head {
+		return
+	}
+	if cache.head != nil {
+		cache.head.next = node
+	}
+	node.prev = cache.head
+	node.next = nil
+	cache.head = node
+	if cache.tail == nil {
+		cache.tail = node
+	}
+	cache.size++
+	cache.clean()
+}
+
+func (cache *RoomCache) clean() {
+	origSize := cache.size
+	maxTS := time.Now().Unix() - cache.maxAge
+	for cache.size > cache.maxSize {
+		if cache.tail.touch > maxTS {
+			break
+		}
+		cache.tail.Unload()
+		cache.llPop(cache.tail)
+	}
+	if cleaned := origSize - cache.size; cleaned > 0 {
+		debug.Print("Cleaned", cleaned, "rooms")
+	}
+}
+
+func (cache *RoomCache) Unload(node *Room) {
+	cache.Lock()
+	defer cache.Unlock()
+	cache.llPop(node)
+	node.Unload()
+}
+
+func (cache *RoomCache) newRoom(roomID string) *Room {
+	node := NewRoom(roomID, cache)
+	cache.Map[node.ID] = node
+	return node
+}