// Package daemon — dispatch_handler.go mounts the orca.v1.Dispatch
// service on the daemon's HTTP server. The service is registered as
// two handlers (POST /orca.v1.Dispatch/Submit and /Status) and is
// gated on the mTLS state — if the server is in plaintext mode
// (v0.1 compat), the handlers refuse to serve.
package daemon

import (
	"net/http"

	"git.cloudinit.dev/coreci/orca/internal/acl"
	"git.cloudinit.dev/coreci/orca/internal/transport"
)

// DispatchHandlers groups the Submit and Status handlers so they
// can be registered as a unit on the daemon mux.
type DispatchHandlers struct {
	Submit *transport.SubmitHandler
	Status *transport.StatusHandler
}

// NewDispatchHandlers builds the dispatch handler pair from a
// transport.Dispatcher (the engine layer satisfies this).
func NewDispatchHandlers(d transport.Dispatcher, dedupe *transport.IdempotencyStore) *DispatchHandlers {
	if dedupe == nil {
		dedupe = transport.NewIdempotencyStore()
	}
	return &DispatchHandlers{
		Submit: transport.NewSubmitHandler(d, dedupe),
		Status: transport.NewStatusHandler(d),
	}
}

// Mount registers Submit and Status on the given mux. Called by the
// daemon's mux builder. P04 wraps each handler in an ACL middleware
// that calls s.acl.Check before delegating; the dispatch namespace is
// the default (cluster-wide) namespace. Submit = write, Status = read.
// When s.acl is nil (legacy/compat) the middleware is a no-op pass-
// through.
func (h *DispatchHandlers) Mount(mux *http.ServeMux) {
	mux.Handle("/orca.v1.Dispatch/Submit", h.Submit)
	mux.Handle("/orca.v1.Dispatch/Status", h.Status)
}

// mountDispatchWithACL mounts the dispatch handlers wrapped in ACL
// middleware. P04: Submit requires write on "_defaults"; Status
// requires read. When policy is nil, the handlers are mounted
// unwrapped (legacy/compat for tests).
func (h *DispatchHandlers) mountWithACL(mux *http.ServeMux, policy *aclPolicy) {
	if policy == nil {
		h.Mount(mux)
		return
	}
	mux.Handle("/orca.v1.Dispatch/Submit", aclMiddleware(policy, "_defaults", acl.PermWrite, h.Submit))
	mux.Handle("/orca.v1.Dispatch/Status", aclMiddleware(policy, "_defaults", acl.PermRead, h.Status))
}

// aclMiddleware wraps an http.Handler with an ACL check. On denial in
// enforce mode it writes a 403 and returns; in log-only mode (C-45)
// it logs and delegates. The extracted identity is stashed in the
// request context under the identity key so downstream handlers / the
// audit layer can read it.
func aclMiddleware(policy *aclPolicy, ns string, perm acl.Permission, next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if id, ok := policy.Check(r, ns, perm); !ok {
			deny(w, id, ns, perm)
			return
		}
		next.ServeHTTP(w, r)
	})
}