package oidcsession

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

func TestLoginTransactionIsEncryptedBoundedAndPKCES256(t *testing.T) {
	now := time.Date(2026, 7, 13, 12, 0, 0, 0, time.UTC)
	cipher, _ := NewCipher(bytes.Repeat([]byte{9}, 32))
	transaction, challenge, err := NewLoginTransaction("/workspace?tab=wallet", now)
	if err != nil {
		t.Fatal(err)
	}
	if transaction.State == transaction.Nonce || len(challenge) != 43 || challenge == transaction.PKCEVerifier {
		t.Fatal("state, nonce and PKCE values are not independent S256 material")
	}
	encoded, err := cipher.EncodeLoginTransaction(transaction)
	if err != nil {
		t.Fatal(err)
	}
	if strings.Contains(encoded, transaction.State) || strings.Contains(encoded, transaction.PKCEVerifier) {
		t.Fatal("login transaction cookie contains plaintext security material")
	}
	decoded, err := cipher.DecodeLoginTransaction(encoded, now.Add(9*time.Minute))
	if err != nil || decoded.ReturnTo != transaction.ReturnTo {
		t.Fatalf("decode transaction=%#v err=%v", decoded, err)
	}
	if _, err := cipher.DecodeLoginTransaction(encoded, now.Add(10*time.Minute)); err == nil {
		t.Fatal("10-minute login transaction was accepted")
	}
}

func TestValidReturnToRejectsOpenRedirects(t *testing.T) {
	for _, value := range []string{"https://evil.example", "//evil.example", "/\\evil", "", "workspace"} {
		if ValidReturnTo(value) {
			t.Fatalf("unsafe returnTo accepted: %q", value)
		}
	}
	if !ValidReturnTo("/workspace/tasks?from=login#latest") {
		t.Fatal("safe relative returnTo was rejected")
	}
}