package auth

import (
	"testing"
	"time"
)

const testSecret = "test-secret-at-least-32-bytes-long!"

func TestMintAndParseSessionCookie(t *testing.T) {
	claims := Claims{Sub: "u1", Name: "Alice", Email: "alice@example.com"}
	cookie, err := MintSessionCookie(claims, []byte(testSecret), time.Hour, true)
	if err != nil {
		t.Fatalf("mint: %v", err)
	}
	if cookie.Name != SessionCookieName || !cookie.HttpOnly || !cookie.Secure {
		t.Fatalf("cookie = %+v, want name=%s HttpOnly+Secure", cookie, SessionCookieName)
	}

	got, err := ParseSessionCookie(cookie, []byte(testSecret))
	if err != nil {
		t.Fatalf("parse: %v", err)
	}
	if got != claims {
		t.Fatalf("got %+v, want %+v", got, claims)
	}
}

func TestParseSessionCookie_Expired(t *testing.T) {
	cookie, err := MintSessionCookie(Claims{Sub: "u1"}, []byte(testSecret), -time.Hour, false)
	if err != nil {
		t.Fatalf("mint: %v", err)
	}
	if _, err := ParseSessionCookie(cookie, []byte(testSecret)); err == nil {
		t.Fatal("expected error for expired cookie")
	}
}

func TestParseSessionCookie_Tampered(t *testing.T) {
	cookie, err := MintSessionCookie(Claims{Sub: "u1"}, []byte(testSecret), time.Hour, false)
	if err != nil {
		t.Fatalf("mint: %v", err)
	}
	cookie.Value = flipLastChar(cookie.Value)
	if _, err := ParseSessionCookie(cookie, []byte(testSecret)); err == nil {
		t.Fatal("expected error for tampered cookie")
	}
}

// flipLastChar corrupts a signed token for tamper tests, guaranteeing the
// last character actually changes -- blindly overwriting it with a fixed
// character (e.g. "x") would occasionally be a no-op if that character
// already happened to be there (it's derived from the token's embedded
// timestamp, so this isn't as rare as it sounds), silently passing the
// test without having tampered with anything.
func flipLastChar(s string) string {
	last := s[len(s)-1]
	replacement := byte('x')
	if last == replacement {
		replacement = 'y'
	}
	return s[:len(s)-1] + string(replacement)
}

func TestParseSessionCookie_WrongSecret(t *testing.T) {
	cookie, err := MintSessionCookie(Claims{Sub: "u1"}, []byte(testSecret), time.Hour, false)
	if err != nil {
		t.Fatalf("mint: %v", err)
	}
	if _, err := ParseSessionCookie(cookie, []byte("a-completely-different-secret!!")); err == nil {
		t.Fatal("expected error for wrong secret")
	}
}

func TestMintAndParseTxnCookie(t *testing.T) {
	txn := TxnState{State: "abc123", CodeVerifier: "verifier-xyz"}
	cookie, err := MintTxnCookie(txn, []byte(testSecret), false)
	if err != nil {
		t.Fatalf("mint: %v", err)
	}
	if cookie.Name != TxnCookieName {
		t.Fatalf("cookie name = %q, want %q", cookie.Name, TxnCookieName)
	}

	got, err := ParseTxnCookie(cookie, []byte(testSecret))
	if err != nil {
		t.Fatalf("parse: %v", err)
	}
	if got != txn {
		t.Fatalf("got %+v, want %+v", got, txn)
	}
}

func TestClearCookie(t *testing.T) {
	c := ClearCookie(SessionCookieName, true)
	if c.Value != "" || c.MaxAge >= 0 {
		t.Fatalf("ClearCookie = %+v, want empty value and negative MaxAge", c)
	}
}