package helps import (	"context"	"crypto/sha256"	"encoding/hex"	"fmt"	"strings"	"sync"	"time" 	"github.com/google/uuid"	homekv "github.com/router-for-me/CLIProxyAPI/v7/internal/home") type sessionIDCacheEntry struct {	value  string	expire time.Time} var (	sessionIDCache            = make(map[string]sessionIDCacheEntry)	sessionIDCacheMu          sync.RWMutex	sessionIDCacheCleanupOnce sync.Once) type claudeIDKVClient interface {	KVGet(ctx context.Context, key string) ([]byte, bool, error)	KVSetNX(ctx context.Context, key string, value []byte, ttl time.Duration) (bool, error)	KVExpire(ctx context.Context, key string, ttl time.Duration) (bool, error)} var currentClaudeIDKVClient = func() (claudeIDKVClient, bool, error) {	return homekv.CurrentKVClient()} const (	sessionIDTTL                = time.Hour	sessionIDCacheCleanupPeriod = 15 * time.Minute) func startSessionIDCacheCleanup() {	go func() {		ticker := time.NewTicker(sessionIDCacheCleanupPeriod)		defer ticker.Stop()		for range ticker.C {			purgeExpiredSessionIDs()		}	}()} func purgeExpiredSessionIDs() {	now := time.Now()	sessionIDCacheMu.Lock()	for key, entry := range sessionIDCache {		if !entry.expire.After(now) {			delete(sessionIDCache, key)		}	}	sessionIDCacheMu.Unlock()} func sessionIDCacheKey(apiKey string) string {	sum := sha256.Sum256([]byte(apiKey))	return hex.EncodeToString(sum[:])} // CachedSessionID returns a stable session UUID per apiKey, refreshing the TTL on each access.func CachedSessionID(apiKey string) string {	value, errValue := CachedSessionIDRequired(context.Background(), apiKey)	if errValue == nil && value != "" {		return value	}	return uuid.New().String()} // CachedSessionIDRequired returns a stable session UUID per apiKey for request-time paths.func CachedSessionIDRequired(ctx context.Context, apiKey string) (string, error) {	if apiKey == "" {		return uuid.New().String(), nil	}	client, homeMode, errClient := currentClaudeIDKVClient()	if homeMode {		if errClient != nil {			return "", errClient		}		key := claudeSessionIDKVKey(apiKey)		raw, found, errGet := client.KVGet(ctx, key)		if errGet != nil {			return "", errGet		}		if found && strings.TrimSpace(string(raw)) != "" {			if _, errExpire := client.KVExpire(ctx, key, sessionIDTTL); errExpire != nil {				return "", errExpire			}			return strings.TrimSpace(string(raw)), nil		}		newID := uuid.New().String()		if _, errSet := client.KVSetNX(ctx, key, []byte(newID), sessionIDTTL); errSet != nil {			return "", errSet		}		raw, found, errGet = client.KVGet(ctx, key)		if errGet != nil {			return "", errGet		}		if found && strings.TrimSpace(string(raw)) != "" {			return strings.TrimSpace(string(raw)), nil		}		return "", fmt.Errorf("home kv session id missing after set")	} 	sessionIDCacheCleanupOnce.Do(startSessionIDCacheCleanup) 	key := sessionIDCacheKey(apiKey)	now := time.Now() 	sessionIDCacheMu.RLock()	entry, ok := sessionIDCache[key]	valid := ok && entry.value != "" && entry.expire.After(now)	sessionIDCacheMu.RUnlock()	if valid {		sessionIDCacheMu.Lock()		entry = sessionIDCache[key]		if entry.value != "" && entry.expire.After(now) {			entry.expire = now.Add(sessionIDTTL)			sessionIDCache[key] = entry			sessionIDCacheMu.Unlock()			return entry.value, nil		}		sessionIDCacheMu.Unlock()	} 	newID := uuid.New().String() 	sessionIDCacheMu.Lock()	entry, ok = sessionIDCache[key]	if !ok || entry.value == "" || !entry.expire.After(now) {		entry.value = newID	}	entry.expire = now.Add(sessionIDTTL)	sessionIDCache[key] = entry	sessionIDCacheMu.Unlock()	return entry.value, nil} func claudeSessionIDKVKey(apiKey string) string {	return "cpa:claude:session-id:" + homekv.HashKeyPart(apiKey)}