// Copyright 2019 The Gitea Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.

package integrations

import (
	"bytes"
	"io/ioutil"
	"testing"

	"code.gitea.io/gitea/modules/setting"

	jsoniter "github.com/json-iterator/go"
	"github.com/stretchr/testify/assert"
)

const defaultAuthorize = "/login/oauth/authorize?client_id=da7da3ba-9a13-4167-856f-3899de0b0138&redirect_uri=a&response_type=code&state=thestate"

func TestNoClientID(t *testing.T) {
	defer prepareTestEnv(t)()
	req := NewRequest(t, "GET", "/login/oauth/authorize")
	ctx := loginUser(t, "user2")
	ctx.MakeRequest(t, req, 400)
}

func TestLoginRedirect(t *testing.T) {
	defer prepareTestEnv(t)()
	req := NewRequest(t, "GET", "/login/oauth/authorize")
	assert.Contains(t, MakeRequest(t, req, 302).Body.String(), "/user/login")
}

func TestShowAuthorize(t *testing.T) {
	defer prepareTestEnv(t)()
	req := NewRequest(t, "GET", defaultAuthorize)
	ctx := loginUser(t, "user4")
	resp := ctx.MakeRequest(t, req, 200)

	htmlDoc := NewHTMLParser(t, resp.Body)
	htmlDoc.AssertElement(t, "#authorize-app", true)
	htmlDoc.GetCSRF()
}

func TestRedirectWithExistingGrant(t *testing.T) {
	defer prepareTestEnv(t)()
	req := NewRequest(t, "GET", defaultAuthorize)
	ctx := loginUser(t, "user1")
	resp := ctx.MakeRequest(t, req, 302)
	u, err := resp.Result().Location()
	assert.NoError(t, err)
	assert.Equal(t, "thestate", u.Query().Get("state"))
	assert.Truef(t, len(u.Query().Get("code")) > 30, "authorization code '%s' should be longer then 30", u.Query().Get("code"))
}

func TestAccessTokenExchange(t *testing.T) {
	defer prepareTestEnv(t)()
	req := NewRequestWithValues(t, "POST", "/login/oauth/access_token", map[string]string{
		"grant_type":    "authorization_code",
		"client_id":     "da7da3ba-9a13-4167-856f-3899de0b0138",
		"client_secret": "4MK8Na6R55smdCY0WuCCumZ6hjRPnGY5saWVRHHjJiA=",
		"redirect_uri":  "a",
		"code":          "authcode",
		"code_verifier": "N1Zo9-8Rfwhkt68r1r29ty8YwIraXR8eh_1Qwxg7yQXsonBt", // test PKCE additionally
	})
	resp := MakeRequest(t, req, 200)
	type response struct {
		AccessToken  string `json:"access_token"`
		TokenType    string `json:"token_type"`
		ExpiresIn    int64  `json:"expires_in"`
		RefreshToken string `json:"refresh_token"`
	}
	parsed := new(response)

	json := jsoniter.ConfigCompatibleWithStandardLibrary
	assert.NoError(t, json.Unmarshal(resp.Body.Bytes(), parsed))
	assert.True(t, len(parsed.AccessToken) > 10)
	assert.True(t, len(parsed.RefreshToken) > 10)
}

func TestAccessTokenExchangeWithoutPKCE(t *testing.T) {
	defer prepareTestEnv(t)()
	req := NewRequestWithJSON(t, "POST", "/login/oauth/access_token", map[string]string{
		"grant_type":    "authorization_code",
		"client_id":     "da7da3ba-9a13-4167-856f-3899de0b0138",
		"client_secret": "4MK8Na6R55smdCY0WuCCumZ6hjRPnGY5saWVRHHjJiA=",
		"redirect_uri":  "a",
		"code":          "authcode",
		"code_verifier": "N1Zo9-8Rfwhkt68r1r29ty8YwIraXR8eh_1Qwxg7yQXsonBt", // test PKCE additionally
	})
	resp := MakeRequest(t, req, 200)
	type response struct {
		AccessToken  string `json:"access_token"`
		TokenType    string `json:"token_type"`
		ExpiresIn    int64  `json:"expires_in"`
		RefreshToken string `json:"refresh_token"`
	}
	parsed := new(response)

	json := jsoniter.ConfigCompatibleWithStandardLibrary
	assert.NoError(t, json.Unmarshal(resp.Body.Bytes(), parsed))
	assert.True(t, len(parsed.AccessToken) > 10)
	assert.True(t, len(parsed.RefreshToken) > 10)
}

func TestAccessTokenExchangeJSON(t *testing.T) {
	defer prepareTestEnv(t)()
	req := NewRequestWithJSON(t, "POST", "/login/oauth/access_token", map[string]string{
		"grant_type":    "authorization_code",
		"client_id":     "da7da3ba-9a13-4167-856f-3899de0b0138",
		"client_secret": "4MK8Na6R55smdCY0WuCCumZ6hjRPnGY5saWVRHHjJiA=",
		"redirect_uri":  "a",
		"code":          "authcode",
	})
	MakeRequest(t, req, 400)
}

func TestAccessTokenExchangeWithInvalidCredentials(t *testing.T) {
	defer prepareTestEnv(t)()
	// invalid client id
	req := NewRequestWithValues(t, "POST", "/login/oauth/access_token", map[string]string{
		"grant_type":    "authorization_code",
		"client_id":     "???",
		"client_secret": "4MK8Na6R55smdCY0WuCCumZ6hjRPnGY5saWVRHHjJiA=",
		"redirect_uri":  "a",
		"code":          "authcode",
		"code_verifier": "N1Zo9-8Rfwhkt68r1r29ty8YwIraXR8eh_1Qwxg7yQXsonBt", // test PKCE additionally
	})
	MakeRequest(t, req, 400)
	// invalid client secret
	req = NewRequestWithValues(t, "POST", "/login/oauth/access_token", map[string]string{
		"grant_type":    "authorization_code",
		"client_id":     "da7da3ba-9a13-4167-856f-3899de0b0138",
		"client_secret": "???",
		"redirect_uri":  "a",
		"code":          "authcode",
		"code_verifier": "N1Zo9-8Rfwhkt68r1r29ty8YwIraXR8eh_1Qwxg7yQXsonBt", // test PKCE additionally
	})
	MakeRequest(t, req, 400)
	// invalid redirect uri
	req = NewRequestWithValues(t, "POST", "/login/oauth/access_token", map[string]string{
		"grant_type":    "authorization_code",
		"client_id":     "da7da3ba-9a13-4167-856f-3899de0b0138",
		"client_secret": "4MK8Na6R55smdCY0WuCCumZ6hjRPnGY5saWVRHHjJiA=",
		"redirect_uri":  "???",
		"code":          "authcode",
		"code_verifier": "N1Zo9-8Rfwhkt68r1r29ty8YwIraXR8eh_1Qwxg7yQXsonBt", // test PKCE additionally
	})
	MakeRequest(t, req, 400)
	// invalid authorization code
	req = NewRequestWithValues(t, "POST", "/login/oauth/access_token", map[string]string{
		"grant_type":    "authorization_code",
		"client_id":     "da7da3ba-9a13-4167-856f-3899de0b0138",
		"client_secret": "4MK8Na6R55smdCY0WuCCumZ6hjRPnGY5saWVRHHjJiA=",
		"redirect_uri":  "a",
		"code":          "???",
		"code_verifier": "N1Zo9-8Rfwhkt68r1r29ty8YwIraXR8eh_1Qwxg7yQXsonBt", // test PKCE additionally
	})
	MakeRequest(t, req, 400)
	// invalid grant_type
	req = NewRequestWithValues(t, "POST", "/login/oauth/access_token", map[string]string{
		"grant_type":    "???",
		"client_id":     "da7da3ba-9a13-4167-856f-3899de0b0138",
		"client_secret": "4MK8Na6R55smdCY0WuCCumZ6hjRPnGY5saWVRHHjJiA=",
		"redirect_uri":  "a",
		"code":          "authcode",
		"code_verifier": "N1Zo9-8Rfwhkt68r1r29ty8YwIraXR8eh_1Qwxg7yQXsonBt", // test PKCE additionally
	})
	MakeRequest(t, req, 400)
}

func TestAccessTokenExchangeWithBasicAuth(t *testing.T) {
	defer prepareTestEnv(t)()
	req := NewRequestWithValues(t, "POST", "/login/oauth/access_token", map[string]string{
		"grant_type":    "authorization_code",
		"redirect_uri":  "a",
		"code":          "authcode",
		"code_verifier": "N1Zo9-8Rfwhkt68r1r29ty8YwIraXR8eh_1Qwxg7yQXsonBt", // test PKCE additionally
	})
	req.Header.Add("Authorization", "Basic ZGE3ZGEzYmEtOWExMy00MTY3LTg1NmYtMzg5OWRlMGIwMTM4OjRNSzhOYTZSNTVzbWRDWTBXdUNDdW1aNmhqUlBuR1k1c2FXVlJISGpKaUE9")
	resp := MakeRequest(t, req, 200)
	type response struct {
		AccessToken  string `json:"access_token"`
		TokenType    string `json:"token_type"`
		ExpiresIn    int64  `json:"expires_in"`
		RefreshToken string `json:"refresh_token"`
	}
	parsed := new(response)

	json := jsoniter.ConfigCompatibleWithStandardLibrary
	assert.NoError(t, json.Unmarshal(resp.Body.Bytes(), parsed))
	assert.True(t, len(parsed.AccessToken) > 10)
	assert.True(t, len(parsed.RefreshToken) > 10)

	// use wrong client_secret
	req = NewRequestWithValues(t, "POST", "/login/oauth/access_token", map[string]string{
		"grant_type":    "authorization_code",
		"redirect_uri":  "a",
		"code":          "authcode",
		"code_verifier": "N1Zo9-8Rfwhkt68r1r29ty8YwIraXR8eh_1Qwxg7yQXsonBt", // test PKCE additionally
	})
	req.Header.Add("Authorization", "Basic ZGE3ZGEzYmEtOWExMy00MTY3LTg1NmYtMzg5OWRlMGIwMTM4OmJsYWJsYQ==")
	resp = MakeRequest(t, req, 400)

	// missing header
	req = NewRequestWithValues(t, "POST", "/login/oauth/access_token", map[string]string{
		"grant_type":    "authorization_code",
		"redirect_uri":  "a",
		"code":          "authcode",
		"code_verifier": "N1Zo9-8Rfwhkt68r1r29ty8YwIraXR8eh_1Qwxg7yQXsonBt", // test PKCE additionally
	})
	resp = MakeRequest(t, req, 400)
}

func TestRefreshTokenInvalidation(t *testing.T) {
	defer prepareTestEnv(t)()
	req := NewRequestWithValues(t, "POST", "/login/oauth/access_token", map[string]string{
		"grant_type":    "authorization_code",
		"client_id":     "da7da3ba-9a13-4167-856f-3899de0b0138",
		"client_secret": "4MK8Na6R55smdCY0WuCCumZ6hjRPnGY5saWVRHHjJiA=",
		"redirect_uri":  "a",
		"code":          "authcode",
		"code_verifier": "N1Zo9-8Rfwhkt68r1r29ty8YwIraXR8eh_1Qwxg7yQXsonBt", // test PKCE additionally
	})
	resp := MakeRequest(t, req, 200)
	type response struct {
		AccessToken  string `json:"access_token"`
		TokenType    string `json:"token_type"`
		ExpiresIn    int64  `json:"expires_in"`
		RefreshToken string `json:"refresh_token"`
	}
	parsed := new(response)

	json := jsoniter.ConfigCompatibleWithStandardLibrary
	assert.NoError(t, json.Unmarshal(resp.Body.Bytes(), parsed))

	// test without invalidation
	setting.OAuth2.InvalidateRefreshTokens = false

	refreshReq := NewRequestWithValues(t, "POST", "/login/oauth/access_token", map[string]string{
		"grant_type":    "refresh_token",
		"client_id":     "da7da3ba-9a13-4167-856f-3899de0b0138",
		"client_secret": "4MK8Na6R55smdCY0WuCCumZ6hjRPnGY5saWVRHHjJiA=",
		"redirect_uri":  "a",
		"refresh_token": parsed.RefreshToken,
	})

	bs, err := ioutil.ReadAll(refreshReq.Body)
	assert.NoError(t, err)

	refreshReq.Body = ioutil.NopCloser(bytes.NewReader(bs))
	MakeRequest(t, refreshReq, 200)

	refreshReq.Body = ioutil.NopCloser(bytes.NewReader(bs))
	MakeRequest(t, refreshReq, 200)

	// test with invalidation
	setting.OAuth2.InvalidateRefreshTokens = true
	refreshReq.Body = ioutil.NopCloser(bytes.NewReader(bs))
	MakeRequest(t, refreshReq, 200)

	refreshReq.Body = ioutil.NopCloser(bytes.NewReader(bs))
	MakeRequest(t, refreshReq, 400)
}
