// Vikunja is a to-do list application to facilitate your life.
// Copyright 2018-present Vikunja and contributors. All rights reserved.
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.

package oauth2server

import (
	"crypto/sha256"
	"encoding/base64"
	"testing"

	"github.com/stretchr/testify/assert"
)

func TestVerifyPKCE(t *testing.T) {
	t.Run("valid S256 verifier", func(t *testing.T) {
		verifier := "dBjftJeZ4CVP-mB92K27uhbUJU1p1r_wW1gFWFOEjXk"
		h := sha256.Sum256([]byte(verifier))
		challenge := base64.RawURLEncoding.EncodeToString(h[:])

		assert.True(t, VerifyPKCE(verifier, challenge, "S256"))
	})

	t.Run("wrong verifier", func(t *testing.T) {
		verifier := "dBjftJeZ4CVP-mB92K27uhbUJU1p1r_wW1gFWFOEjXk"
		h := sha256.Sum256([]byte(verifier))
		challenge := base64.RawURLEncoding.EncodeToString(h[:])

		assert.False(t, VerifyPKCE("wrong-verifier", challenge, "S256"))
	})

	t.Run("unsupported method", func(t *testing.T) {
		assert.False(t, VerifyPKCE("verifier", "challenge", "plain"))
	})

	t.Run("empty method", func(t *testing.T) {
		assert.False(t, VerifyPKCE("verifier", "challenge", ""))
	})
}