Add metrics

metrics/metrics.go

@@ -0,0 +1,148 @@
+package metrics
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"sync"
+	"time"
+)
+
+type CommandStats struct {
+	AllTime   int     `json:"all_time"`
+	Last30    [30]int `json:"last_30"`
+	Last30Day int64   `json:"last_30_day"` // Unix day of the first slot
+}
+
+type ChatInfo struct {
+	IsGroup    bool   `json:"is_group"`
+	LastActive int64  `json:"last_active"`
+	Blocked    bool   `json:"blocked"`
+	LastError  string `json:"last_error,omitempty"`
+}
+
+type Metrics struct {
+	Commands map[string]*CommandStats `json:"commands"`
+	Chats    map[int64]*ChatInfo      `json:"chats"`
+}
+
+var (
+	metricsFile = "metrics/metrics.json"
+	metrics     *Metrics
+	mu          sync.Mutex
+)
+
+func loadMetrics() {
+	if metrics != nil {
+		return
+	}
+	metrics = &Metrics{
+		Commands: make(map[string]*CommandStats),
+		Chats:    make(map[int64]*ChatInfo),
+	}
+	f, err := os.Open(metricsFile)
+	if err != nil {
+		return
+	}
+	defer f.Close()
+	json.NewDecoder(f).Decode(metrics)
+}
+
+func saveMetrics() {
+	// Do not lock here; caller must hold the lock else it will shitty deadlock
+	loadMetrics()
+	f, err := os.Create(metricsFile)
+	if err != nil {
+		return
+	}
+	defer f.Close()
+	enc := json.NewEncoder(f)
+	enc.SetIndent("", "  ")
+	enc.Encode(metrics)
+}
+
+func IncrementCommandUsage(cmd string) {
+	fmt.Printf("[metrics] IncrementCommandUsage called with cmd=%s\n", cmd)
+	mu.Lock()
+	defer mu.Unlock()
+	loadMetrics()
+	stat, ok := metrics.Commands[cmd]
+	if !ok {
+		stat = &CommandStats{Last30Day: time.Now().Unix() / 86400}
+		metrics.Commands[cmd] = stat
+	}
+	today := time.Now().Unix() / 86400
+	shift := int(today - stat.Last30Day)
+	if shift > 0 && shift < 30 {
+		copy(stat.Last30[shift:], stat.Last30[:30-shift])
+		for i := 0; i < shift; i++ {
+			stat.Last30[i] = 0
+		}
+		stat.Last30Day = today
+	} else if shift >= 30 {
+		for i := 0; i < 30; i++ {
+			stat.Last30[i] = 0
+		}
+		stat.Last30Day = today
+	}
+	stat.AllTime++
+	stat.Last30[0]++
+	saveMetrics()
+}
+
+func UpdateChat(chatID int64, isGroup bool) {
+	fmt.Printf("[metrics] UpdateChat called with chatID=%d isGroup=%v\n", chatID, isGroup)
+	mu.Lock()
+	defer mu.Unlock()
+	loadMetrics()
+	info, ok := metrics.Chats[chatID]
+	if !ok {
+		info = &ChatInfo{IsGroup: isGroup}
+		metrics.Chats[chatID] = info
+	}
+	info.LastActive = time.Now().Unix()
+	info.Blocked = false
+	info.LastError = ""
+	saveMetrics()
+}
+
+func MarkChatBlocked(chatID int64, errMsg string) {
+	fmt.Printf("[metrics] MarkChatBlocked called with chatID=%d errMsg=%s\n", chatID, errMsg)
+	mu.Lock()
+	defer mu.Unlock()
+	loadMetrics()
+	info, ok := metrics.Chats[chatID]
+	if !ok {
+		info = &ChatInfo{}
+		metrics.Chats[chatID] = info
+	}
+	info.Blocked = true
+	info.LastError = errMsg
+	saveMetrics()
+}
+
+func GetStats() *Metrics {
+	fmt.Printf("[metrics] GetStats called\n")
+	mu.Lock()
+	defer mu.Unlock()
+	loadMetrics()
+	copy := *metrics
+	return &copy
+}
+
+func BroadcastMessage(sendFunc func(chatID int64) error) {
+	fmt.Printf("[metrics] BroadcastMessage called\n")
+	mu.Lock()
+	loadMetrics()
+	ids := make([]int64, 0, len(metrics.Chats))
+	for id := range metrics.Chats {
+		ids = append(ids, id)
+	}
+	mu.Unlock()
+	for _, id := range ids {
+		err := sendFunc(id)
+		if err != nil {
+			MarkChatBlocked(id, err.Error())
+		}
+	}
+}