felhom.eu/hub/internal/claim/language_test.go

package claim

import (
	"strings"
	"testing"
)

// R-597 — THE WIRING, not the generator.
//
// configgen's own tests prove it CAN mint an English code. These prove the engine ASKS it to: the
// mechanism-vs-consequence distinction this project has been bitten by (R-97b). A perfectly correct
// generator that nobody calls with the household's language leaves the English drill exactly where
// it was.

// isASCIILower is the property that actually matters to a household: every letter is on their
// keyboard. A Hungarian code from the ~29K list carries accents on almost every draw.
func isASCIILower(s string) bool {
	for _, r := range s {
		if (r < 'a' || r > 'z') && r != '-' {
			return false
		}
	}
	return true
}

// An English household's setup code is made of English words — asserted on the code the MAILER
// received, which is the string that reaches the customer's inbox.
func TestSetupCodeFollowsTheHouseholdLanguage(t *testing.T) {
	for _, tc := range []struct {
		lang      string
		wantWords int
		wantASCII bool
	}{
		{"en", 4, true},
		{"hu", 3, false},
	} {
		e, st, m := newTestEngine(t)
		cc := cust()
		cc.Language = tc.lang
		if err := st.SaveCustomerConfig(cc); err != nil {
			t.Fatalf("[%s] SaveCustomerConfig: %v", tc.lang, err)
		}
		if _, err := e.EnsureIssued(cc); err != nil {
			t.Fatalf("[%s] EnsureIssued: %v", tc.lang, err)
		}
		if len(m.sends) != 1 {
			t.Fatalf("[%s] expected one mail, got %v", tc.lang, m.sends)
		}
		words := strings.Split(m.lastCode, "-")
		if len(words) != tc.wantWords {
			t.Errorf("[%s] the code has %d words, want %d (code shape only — the code itself is never "+
				"logged): %d segments", tc.lang, len(words), tc.wantWords, len(words))
		}
		if tc.wantASCII && !isASCIILower(m.lastCode) {
			t.Errorf("[%s] the mailed setup code is not plain ASCII — an English household cannot type "+
				"it. This is exactly what the 2026-09-20 drill received.", tc.lang)
		}
	}
}

// A household created as Hungarian whose BOX later reports English: the next code follows the
// language the hub would write the mail in, which is CustomerLanguage's order (reported → created →
// Hungarian). Documented in 05-hub-architecture.md; pinned here so the two cannot drift.
func TestANewCodeFollowsTheSameOrderAsTheMail(t *testing.T) {
	e, st, m := newTestEngine(t)
	cc := cust()
	cc.Language = "hu"
	if err := st.SaveCustomerConfig(cc); err != nil {
		t.Fatal(err)
	}
	if _, err := e.EnsureIssued(cc); err != nil {
		t.Fatal(err)
	}
	if n := len(strings.Split(m.lastCode, "-")); n != 3 {
		t.Fatalf("the created-as-Hungarian code has %d words, want 3", n)
	}

	// The box now reports that the household switched their dashboard to English.
	if err := st.SaveReport("c1", []byte(`{"language":"en"}`)); err != nil {
		t.Fatalf("SaveReport: %v", err)
	}
	if got := st.CustomerLanguage("c1"); got != "en" {
		t.Fatalf("CustomerLanguage is %q after an English report, want \"en\" — the fixture is wrong, "+
			"not the code under test", got)
	}
	// RequestReset is the real "Forgot password" path — the one the drill's missing step walks.
	if err := e.RequestReset(cc); err != nil {
		t.Fatalf("RequestReset: %v", err)
	}
	if !isASCIILower(m.lastCode) {
		t.Errorf("after the household switched to English, the NEXT code is still Hungarian — the code " +
			"and the mail that carries it now disagree about the language")
	}
	if n := len(strings.Split(m.lastCode, "-")); n != 4 {
		t.Errorf("the English code has %d words, want 4", n)
	}
	// Codes ALREADY ISSUED are untouched: rotation mints a new one, it does not retranslate an old
	// one. Nothing to assert beyond the generation moving, which the engine's own tests cover.
}