first

backend/internal/topics/tree.go

@@ -0,0 +1,109 @@
+package topics
+
+import (
+	"sort"
+	"strings"
+	"sync"
+	"time"
+)
+
+type Message struct {
+	ID        string    `json:"id"`
+	Topic     string    `json:"topic"`
+	Payload   string    `json:"payload"`
+	QOS       byte      `json:"qos"`
+	Retained  bool      `json:"retained"`
+	Timestamp time.Time `json:"timestamp"`
+	Size      int       `json:"size"`
+}
+
+type Tree struct {
+	mu   sync.RWMutex
+	root *node
+}
+
+type node struct {
+	name         string
+	fullName     string
+	children     map[string]*node
+	messageCount int
+	lastMessage  *Message
+}
+
+type NodeSnapshot struct {
+	Name         string          `json:"name"`
+	FullName     string          `json:"fullName"`
+	MessageCount int             `json:"messageCount"`
+	LastMessage  *Message        `json:"lastMessage,omitempty"`
+	Children     []NodeSnapshot  `json:"children"`
+}
+
+func NewTree() *Tree {
+	return &Tree{
+		root: &node{
+			name:     "root",
+			fullName: "",
+			children: make(map[string]*node),
+		},
+	}
+}
+
+func (t *Tree) AddMessage(msg Message) {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+
+	parts := strings.Split(msg.Topic, "/")
+	current := t.root
+	for i, part := range parts {
+		child, ok := current.children[part]
+		if !ok {
+			full := strings.Join(parts[:i+1], "/")
+			child = &node{
+				name:     part,
+				fullName: full,
+				children: make(map[string]*node),
+			}
+			current.children[part] = child
+		}
+		current = child
+		current.messageCount++
+		if i == len(parts)-1 {
+			copyMsg := msg
+			current.lastMessage = &copyMsg
+		}
+	}
+}
+
+func (t *Tree) Snapshot() NodeSnapshot {
+	t.mu.RLock()
+	defer t.mu.RUnlock()
+
+	return snapshotNode(t.root)
+}
+
+func snapshotNode(n *node) NodeSnapshot {
+	children := make([]NodeSnapshot, 0, len(n.children))
+	keys := make([]string, 0, len(n.children))
+	for key := range n.children {
+		keys = append(keys, key)
+	}
+	sort.Strings(keys)
+	for _, key := range keys {
+		child := n.children[key]
+		children = append(children, snapshotNode(child))
+	}
+
+	var last *Message
+	if n.lastMessage != nil {
+		copyMsg := *n.lastMessage
+		last = &copyMsg
+	}
+
+	return NodeSnapshot{
+		Name:         n.name,
+		FullName:     n.fullName,
+		MessageCount: n.messageCount,
+		LastMessage:  last,
+		Children:     children,
+	}
+}