1 files changed, 51 insertions, 0 deletions
diff --git a/network/receivepack/hooks/chain.go b/network/receivepack/hooks/chain.go
new file mode 100644
index 00000000..f98c06f8
--- /dev/null
+++ b/network/receivepack/hooks/chain.go
@@ -0,0 +1,51 @@
+package hooks
+
+import (
+	"context"
+	"fmt"
+
+	receivepack "codeberg.org/lindenii/furgit/network/receivepack"
+)
+
+// Chain combines hooks by running them in order and intersecting their
+// decisions. The first rejecting message for each update is preserved.
+func Chain(hooks ...receivepack.Hook) receivepack.Hook {
+	return func(
+		ctx context.Context,
+		req receivepack.HookRequest,
+	) ([]receivepack.UpdateDecision, error) {
+		decisions := make([]receivepack.UpdateDecision, len(req.Updates))
+		for i := range decisions {
+			decisions[i].Accept = true
+		}
+
+		for _, hook := range hooks {
+			if hook == nil {
+				continue
+			}
+
+			hookDecisions, err := hook(ctx, req)
+			if err != nil {
+				return nil, err
+			}
+
+			if len(hookDecisions) != len(req.Updates) {
+				return nil, fmt.Errorf("hook returned %d decisions for %d updates", len(hookDecisions), len(req.Updates))
+			}
+
+			for i, decision := range hookDecisions {
+				if decision.Accept {
+					continue
+				}
+
+				if decisions[i].Accept {
+					decisions[i].Message = decision.Message
+				}
+
+				decisions[i].Accept = false
+			}
+		}
+
+		return decisions, nil
+	}
+}