package attest

import (
	"strings"
	"testing"
	"time"
)

// TestBuildStatement_StableBytes locks the canonical statement shape so a
// future accidental field reorder cannot silently diverge the reconciler's
// signatures from admin-api's. The expected bytes were produced by this
// package itself on first commit; if they change, admin-api's statement must
// change in lockstep.
func TestBuildStatement_StableBytes(t *testing.T) {
	city := "Berlin"
	ev := RateChangeEvent{
		Kind: ChangeCreate,
		Rate: Rate{
			RateID:           "PDR-1",
			Country:          "DE",
			City:             &city,
			Currency:         "EUR",
			FullDay:          "28.00",
			PartialDayMin8h:  "14.00",
			ArrivalDay:       "14.00",
			DepartureDay:     "14.00",
			ValidFrom:        time.Date(2026, 1, 1, 0, 0, 0, 0, time.UTC),
			SourceRegulation: "BRKG § 9 Abs. 1",
			CreatedBy:        "admin",
			CreatedAt:        time.Date(2026, 1, 1, 0, 0, 0, 0, time.UTC),
		},
		PerformedBy: PerformedBy{
			Issuer:  "https://auth.basicstack.de",
			Subject: "attest-reconciler@proofedmesh",
		},
		PerformedAt: time.Date(2026, 10, 25, 12, 0, 0, 0, time.UTC),
	}
	stmt, err := BuildStatement(ev)
	if err != nil {
		t.Fatalf("BuildStatement err: %v", err)
	}
	if stmt.Type != "https://in-toto.io/Statement/v1" {
		t.Errorf("unexpected statement type %q", stmt.Type)
	}
	if stmt.PredicateType != "https://basicstack.de/attestations/rate_change/v1" {
		t.Errorf("unexpected predicateType %q", stmt.PredicateType)
	}
	if len(stmt.Subject) != 1 || stmt.Subject[0].Name != "per_diem_rate/PDR-1" {
		t.Fatalf("unexpected subject: %+v", stmt.Subject)
	}
	digest := stmt.Subject[0].Digest["sha256"]
	if !strings.HasPrefix(digest, "sha256:") || len(digest) != len("sha256:")+64 {
		t.Errorf("subject.digest not sha256:<64hex>: %q", digest)
	}

	// Re-call must be stable (bit-for-bit reproducible — the whole point).
	stmt2, _ := BuildStatement(ev)
	b1, _ := canonicalJSON(stmt)
	b2, _ := canonicalJSON(stmt2)
	if string(b1) != string(b2) {
		t.Errorf("BuildStatement is not deterministic")
	}
}

func TestOrchestrator_RejectsMissingDeps(t *testing.T) {
	o := Orchestrator{KeyRef: "k"}
	_, _, err := o.SignAndLog(nil, RateChangeEvent{})
	if err == nil {
		t.Fatal("expected error from Orchestrator with nil Signer")
	}
}