init

2026-05-14 13:38:41 +02:00
parent 5d1ced594d
commit be7bd79fc7
16 changed files with 1434 additions and 1 deletions
@@ -0,0 +1,187 @@
+package store
+
+import (
+	"encoding/json"
+	"errors"
+	"os"
+	"path/filepath"
+	"sort"
+	"sync"
+	"time"
+)
+
+var ErrNotFound = errors.New("not found")
+
+type Room struct {
+	ID          int64     `json:"id"`
+	Name        string    `json:"name"`
+	Description string    `json:"description"`
+	CreatedAt   time.Time `json:"created_at"`
+}
+
+type Message struct {
+	ID        int64     `json:"id"`
+	RoomID    int64     `json:"room_id"`
+	Username  string    `json:"username"`
+	Body      string    `json:"body"`
+	CreatedAt time.Time `json:"created_at"`
+}
+
+type Store struct {
+	mu            sync.RWMutex
+	path          string
+	nextRoomID    int64
+	nextMessageID int64
+	rooms         []Room
+	messages      []Message
+}
+
+type diskData struct {
+	NextRoomID    int64     `json:"next_room_id"`
+	NextMessageID int64     `json:"next_message_id"`
+	Rooms         []Room    `json:"rooms"`
+	Messages      []Message `json:"messages"`
+}
+
+func Open(path string) (*Store, error) {
+	s := &Store{path: path, nextRoomID: 1, nextMessageID: 1}
+	if err := s.load(); err != nil {
+		return nil, err
+	}
+	if len(s.rooms) == 0 {
+		now := time.Now().UTC()
+		s.rooms = []Room{
+			{ID: s.nextRoomID, Name: "Lobby", Description: "Allgemeiner Chat für alle", CreatedAt: now},
+			{ID: s.nextRoomID + 1, Name: "Go", Description: "Golang, Backend und Deployment", CreatedAt: now},
+			{ID: s.nextRoomID + 2, Name: "Random", Description: "Alles, was sonst nirgends passt", CreatedAt: now},
+		}
+		s.nextRoomID += 3
+		if err := s.saveLocked(); err != nil {
+			return nil, err
+		}
+	}
+	return s, nil
+}
+
+func (s *Store) Close() error { return nil }
+
+func (s *Store) load() error {
+	b, err := os.ReadFile(s.path)
+	if errors.Is(err, os.ErrNotExist) {
+		return nil
+	}
+	if err != nil {
+		return err
+	}
+	var d diskData
+	if err := json.Unmarshal(b, &d); err != nil {
+		return err
+	}
+	s.nextRoomID = maxInt64(d.NextRoomID, 1)
+	s.nextMessageID = maxInt64(d.NextMessageID, 1)
+	s.rooms = d.Rooms
+	s.messages = d.Messages
+	return nil
+}
+
+func (s *Store) saveLocked() error {
+	if err := os.MkdirAll(filepath.Dir(s.path), 0o755); err != nil && filepath.Dir(s.path) != "." {
+		return err
+	}
+	d := diskData{NextRoomID: s.nextRoomID, NextMessageID: s.nextMessageID, Rooms: s.rooms, Messages: s.messages}
+	b, err := json.MarshalIndent(d, "", "  ")
+	if err != nil {
+		return err
+	}
+	tmp := s.path + ".tmp"
+	if err := os.WriteFile(tmp, b, 0o600); err != nil {
+		return err
+	}
+	return os.Rename(tmp, s.path)
+}
+
+func (s *Store) Rooms() ([]Room, error) {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	rooms := append([]Room(nil), s.rooms...)
+	sort.Slice(rooms, func(i, j int) bool { return rooms[i].Name < rooms[j].Name })
+	return rooms, nil
+}
+
+func (s *Store) CreateRoom(name, description string) (Room, error) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	for _, r := range s.rooms {
+		if r.Name == name {
+			return Room{}, errors.New("room exists")
+		}
+	}
+	r := Room{ID: s.nextRoomID, Name: name, Description: description, CreatedAt: time.Now().UTC()}
+	s.nextRoomID++
+	s.rooms = append(s.rooms, r)
+	if err := s.saveLocked(); err != nil {
+		return Room{}, err
+	}
+	return r, nil
+}
+
+func (s *Store) Room(id int64) (Room, error) {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	for _, r := range s.rooms {
+		if r.ID == id {
+			return r, nil
+		}
+	}
+	return Room{}, ErrNotFound
+}
+
+func (s *Store) RecentMessages(roomID int64, limit int) ([]Message, error) {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	var msgs []Message
+	for _, m := range s.messages {
+		if m.RoomID == roomID {
+			msgs = append(msgs, m)
+		}
+	}
+	sort.Slice(msgs, func(i, j int) bool {
+		if msgs[i].CreatedAt.Equal(msgs[j].CreatedAt) {
+			return msgs[i].ID < msgs[j].ID
+		}
+		return msgs[i].CreatedAt.Before(msgs[j].CreatedAt)
+	})
+	if limit > 0 && len(msgs) > limit {
+		msgs = msgs[len(msgs)-limit:]
+	}
+	return append([]Message(nil), msgs...), nil
+}
+
+func (s *Store) AddMessage(roomID int64, username, body string) (Message, error) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	found := false
+	for _, r := range s.rooms {
+		if r.ID == roomID {
+			found = true
+			break
+		}
+	}
+	if !found {
+		return Message{}, ErrNotFound
+	}
+	m := Message{ID: s.nextMessageID, RoomID: roomID, Username: username, Body: body, CreatedAt: time.Now().UTC()}
+	s.nextMessageID++
+	s.messages = append(s.messages, m)
+	if err := s.saveLocked(); err != nil {
+		return Message{}, err
+	}
+	return m, nil
+}
+
+func maxInt64(a, b int64) int64 {
+	if a > b {
+		return a
+	}
+	return b
+}