package link

import (
	"encoding/json"
	"testing"
)

func TestTheWireFormatIsExactlyTheseFieldNames(t *testing.T) {
	// The contract with the host, which defines these separately because it requires nothing
	// present and does not import this. A matching test lives there; rename a field on either
	// side and both fail, rather than the mismatch surfacing on a real machine.
	for _, c := range []struct {
		value  any
		expect []string
	}{
		{Signed{Declaration: []byte("{}"), Signature: []byte("x")}, []string{"declaration", "signature"}},
		{Report{Node: "n", Applied: []string{"a"}, Failed: map[string]string{"k": "v"}, Refused: "r"},
			[]string{"node", "applied", "failed", "refused"}},
		{Report{Node: "n", Held: []Held{{ID: "m.f"}}, Firewall: "ufw", Reachable: []Reach{{Port: 1}}},
			[]string{"node", "held", "firewall", "reachable"}},
		{Held{ID: "m.f", Module: "m", Kind: "file", Target: "/f", Changed: "rewritten", Kept: "/k"},
			[]string{"id", "module", "kind", "target", "since", "changed", "kept"}},
		{Reach{Protocol: "tcp", Address: "0.0.0.0", Port: 8080, By: "hello-web", Published: true,
			ContainerPort: 80},
			[]string{"protocol", "address", "port", "by", "published", "container-port"}},
		{EnrolRequest{Node: "n", Secret: "s", PublicKey: []byte("k")},
			[]string{"node", "secret", "public_key"}},
	} {
		raw, err := json.Marshal(c.value)
		if err != nil {
			t.Fatal(err)
		}
		var fields map[string]any
		if err := json.Unmarshal(raw, &fields); err != nil {
			t.Fatal(err)
		}
		for _, want := range c.expect {
			if _, ok := fields[want]; !ok {
				t.Errorf("%T has no %q field; the host reads that name", c.value, want)
			}
		}
		if len(fields) != len(c.expect) {
			t.Errorf("%T has %d fields, expected %d: %v", c.value, len(fields), len(c.expect), fields)
		}
	}
}