package imapx

import (
	"testing"
	"time"

	"github.com/emersion/go-imap/v2"
)

func TestMessageKeyPrefersMessageID(t *testing.T) {
	env := &imap.Envelope{MessageID: "<abc@host>"}
	if got := MessageKey(env, 100); got != "<abc@host>" {
		t.Fatalf("got %q, want <abc@host>", got)
	}
}

func TestMessageKeyFallbackStable(t *testing.T) {
	env := &imap.Envelope{
		Subject: "Hi",
		Date:    time.Unix(1700000000, 0).UTC(),
		From:    []imap.Address{{Mailbox: "a", Host: "x.com"}},
		To:      []imap.Address{{Mailbox: "b", Host: "y.com"}},
	}
	k1 := MessageKey(env, 42)
	k2 := MessageKey(env, 42)
	if k1 != k2 {
		t.Fatal("fallback key must be deterministic")
	}
	if MessageKey(env, 43) == k1 {
		t.Fatal("different size must change key")
	}
}