refactor(context): carry route and scope through runtime

pkg/session/allocator.go

@@ -1,6 +1,7 @@
 package session
 
 import (
+	"fmt"
 	"strings"
 
 	"github.com/sipeed/picoclaw/pkg/routing"
@@ -10,6 +11,7 @@ import (
 // The current implementation intentionally preserves the legacy session-key
 // layout while moving key construction out of the router.
 type Allocation struct {
+	Scope          SessionScope
 	SessionKey     string
 	MainSessionKey string
 }
@@ -27,6 +29,7 @@ type AllocationInput struct {
 // AllocateRouteSession maps a route decision onto the current legacy
 // agent-scoped session-key format.
 func AllocateRouteSession(input AllocationInput) Allocation {
+	scope := buildSessionScope(input)
 	sessionKey := strings.ToLower(routing.BuildAgentPeerSessionKey(routing.SessionKeyParams{
 		AgentID:       input.AgentID,
 		Channel:       input.Channel,
@@ -37,7 +40,58 @@ func AllocateRouteSession(input AllocationInput) Allocation {
 	}))
 	mainSessionKey := strings.ToLower(routing.BuildAgentMainSessionKey(input.AgentID))
 	return Allocation{
+		Scope:          scope,
 		SessionKey:     sessionKey,
 		MainSessionKey: mainSessionKey,
 	}
 }
+
+func buildSessionScope(input AllocationInput) SessionScope {
+	scope := SessionScope{
+		Version: ScopeVersionV1,
+		AgentID: routing.NormalizeAgentID(input.AgentID),
+		Channel: strings.ToLower(strings.TrimSpace(input.Channel)),
+		Account: routing.NormalizeAccountID(input.AccountID),
+	}
+
+	peer := input.Peer
+	if peer == nil {
+		peer = &routing.RoutePeer{Kind: "direct"}
+	}
+
+	peerKind := strings.ToLower(strings.TrimSpace(peer.Kind))
+	if peerKind == "" {
+		peerKind = "direct"
+	}
+
+	switch peerKind {
+	case "direct":
+		if input.SessionPolicy.DMScope == routing.DMScopeMain {
+			return scope
+		}
+		peerID := routing.CanonicalSessionPeerID(
+			input.Channel,
+			peer.ID,
+			input.SessionPolicy.DMScope,
+			input.SessionPolicy.IdentityLinks,
+		)
+		if peerID == "" {
+			return scope
+		}
+		scope.Dimensions = []string{"sender"}
+		scope.Values = map[string]string{
+			"sender": peerID,
+		}
+	default:
+		peerID := strings.ToLower(strings.TrimSpace(peer.ID))
+		if peerID == "" {
+			peerID = "unknown"
+		}
+		scope.Dimensions = []string{"chat"}
+		scope.Values = map[string]string{
+			"chat": fmt.Sprintf("%s:%s", peerKind, peerID),
+		}
+	}
+
+	return scope
+}