package registry

import "testing"

func claimFingerprints(t *testing.T, r *Registry) (string, string) {
	t.Helper()
	f, err := r.Fingerprint()
	if err != nil {
		t.Fatal(err)
	}
	s, err := r.SnapshotFingerprint()
	if err != nil {
		t.Fatal(err)
	}
	return f, s
}

// Each ownership column moves both fingerprints on its own, partial
// ownership included, and clearing it returns the exact default digests.
func TestFingerprintsSeeEachClaimOwnershipField(t *testing.T) {
	reg := openTestRegistry(t)
	if err := reg.Upsert(Route{Host: "c", Kind: "instance", Socket: "/s", App: "a", CreatedAt: 1700000000}); err != nil {
		t.Fatal(err)
	}
	defF, defS := claimFingerprints(t, reg)

	set := func(assign string, args ...any) {
		t.Helper()
		if _, err := reg.sql.Exec(`UPDATE routes SET `+assign+` WHERE host = 'c'`, args...); err != nil {
			t.Fatal(err)
		}
	}
	const clear = `claim_incarnation = '', claim_stamp = 0, claim_owner = '', claim_row_id = ''`

	cases := []struct {
		name   string
		assign string
		args   []any
	}{
		{"incarnation", `claim_incarnation = ?`, []any{"i1"}},
		{"zero-incarnation", `claim_incarnation = ?`, []any{"0"}},
		{"zero-owner", `claim_owner = ?`, []any{"0"}},
		{"zero-row_id", `claim_row_id = ?`, []any{"0"}},
		{"stamp", `claim_stamp = ?`, []any{7}},
		{"owner", `claim_owner = ?`, []any{"o1"}},
		{"row_id", `claim_row_id = ?`, []any{"r1"}},
		{"incarnation+owner", `claim_incarnation = ?, claim_owner = ?`, []any{"i1", "o1"}},
		{"stamp+row_id", `claim_stamp = ?, claim_row_id = ?`, []any{7, "r1"}},
		{"full", `claim_incarnation = ?, claim_stamp = ?, claim_owner = ?, claim_row_id = ?`, []any{"i1", 7, "o1", "r1"}},
	}
	seenF := map[string]string{}
	seenS := map[string]string{}
	for _, c := range cases {
		set(c.assign, c.args...)
		f, s := claimFingerprints(t, reg)
		if f == defF {
			t.Errorf("%s: Fingerprint did not change", c.name)
		}
		if s == defS {
			t.Errorf("%s: SnapshotFingerprint did not change", c.name)
		}
		if prev, dup := seenF[f]; dup {
			t.Errorf("%s: Fingerprint collides with %s", c.name, prev)
		}
		if prev, dup := seenS[s]; dup {
			t.Errorf("%s: SnapshotFingerprint collides with %s", c.name, prev)
		}
		seenF[f], seenS[s] = c.name, c.name

		set(clear)
		if f, s := claimFingerprints(t, reg); f != defF || s != defS {
			t.Errorf("%s: cleared ownership did not restore default digests", c.name)
		}
	}
}

// The same value in different ownership fields must not hash alike.
func TestFingerprintsDistinguishClaimFieldsHoldingSameValue(t *testing.T) {
	reg := openTestRegistry(t)
	if err := reg.Upsert(Route{Host: "c", Kind: "instance", Socket: "/s", CreatedAt: 1700000000}); err != nil {
		t.Fatal(err)
	}
	digests := func(assign string) (string, string) {
		t.Helper()
		if _, err := reg.sql.Exec(`UPDATE routes SET claim_incarnation = '', claim_owner = '', claim_row_id = '', ` + assign + ` WHERE host = 'c'`); err != nil {
			t.Fatal(err)
		}
		return claimFingerprints(t, reg)
	}
	fa, sa := digests(`claim_owner = 'x'`)
	fb, sb := digests(`claim_row_id = 'x'`)
	fc, sc := digests(`claim_incarnation = 'x'`)
	if fa == fb || fa == fc || fb == fc {
		t.Error("Fingerprint aliases ownership fields")
	}
	if sa == sb || sa == sc || sb == sc {
		t.Error("SnapshotFingerprint aliases ownership fields")
	}
}