package idp

import (
	"context"
	"fmt"
	"io"
	"strings"
	"testing"
	"time"

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

	"github.com/netbirdio/netbird/management/server/telemetry"
)

func TestNewKeycloakManager(t *testing.T) {
	type test struct {
		name                 string
		inputConfig          KeycloakClientConfig
		assertErrFunc        require.ErrorAssertionFunc
		assertErrFuncMessage string
	}

	defaultTestConfig := KeycloakClientConfig{
		ClientID:      "client_id",
		ClientSecret:  "client_secret",
		AdminEndpoint: "https://localhost:8080/auth/admin/realms/test123",
		TokenEndpoint: "https://localhost:8080/auth/realms/test123/protocol/openid-connect/token",
		GrantType:     "client_credentials",
	}

	testCase1 := test{
		name:                 "Good Configuration",
		inputConfig:          defaultTestConfig,
		assertErrFunc:        require.NoError,
		assertErrFuncMessage: "shouldn't return error",
	}

	testCase2Config := defaultTestConfig
	testCase2Config.ClientID = ""

	testCase2 := test{
		name:                 "Missing ClientID Configuration",
		inputConfig:          testCase2Config,
		assertErrFunc:        require.Error,
		assertErrFuncMessage: "should return error when field empty",
	}

	testCase3Config := defaultTestConfig
	testCase3Config.ClientSecret = ""

	testCase3 := test{
		name:                 "Missing ClientSecret Configuration",
		inputConfig:          testCase3Config,
		assertErrFunc:        require.Error,
		assertErrFuncMessage: "should return error when field empty",
	}

	testCase4Config := defaultTestConfig
	testCase4Config.TokenEndpoint = ""

	testCase4 := test{
		name:                 "Missing TokenEndpoint Configuration",
		inputConfig:          testCase3Config,
		assertErrFunc:        require.Error,
		assertErrFuncMessage: "should return error when field empty",
	}

	testCase5Config := defaultTestConfig
	testCase5Config.GrantType = ""

	testCase5 := test{
		name:                 "Missing GrantType Configuration",
		inputConfig:          testCase3Config,
		assertErrFunc:        require.Error,
		assertErrFuncMessage: "should return error when field empty",
	}

	for _, testCase := range []test{testCase1, testCase2, testCase3, testCase4, testCase5} {
		t.Run(testCase.name, func(t *testing.T) {
			_, err := NewKeycloakManager(testCase.inputConfig, &telemetry.MockAppMetrics{})
			testCase.assertErrFunc(t, err, testCase.assertErrFuncMessage)
		})
	}
}

func TestKeycloakRequestJWTToken(t *testing.T) {

	type requestJWTTokenTest struct {
		name                    string
		inputCode               int
		inputRespBody           string
		helper                  ManagerHelper
		expectedFuncExitErrDiff error
		expectedToken           string
	}
	exp := 5
	token := newTestJWT(t, exp)

	requestJWTTokenTesttCase1 := requestJWTTokenTest{
		name:          "Good JWT Response",
		inputCode:     200,
		inputRespBody: fmt.Sprintf("{\"access_token\":\"%s\",\"scope\":\"read:users\",\"expires_in\":%d,\"token_type\":\"Bearer\"}", token, exp),
		helper:        JsonParser{},
		expectedToken: token,
	}
	requestJWTTokenTestCase2 := requestJWTTokenTest{
		name:                    "Request Bad Status Code",
		inputCode:               400,
		inputRespBody:           "{}",
		helper:                  JsonParser{},
		expectedFuncExitErrDiff: fmt.Errorf("unable to get keycloak token, statusCode 400"),
		expectedToken:           "",
	}

	for _, testCase := range []requestJWTTokenTest{requestJWTTokenTesttCase1, requestJWTTokenTestCase2} {
		t.Run(testCase.name, func(t *testing.T) {

			jwtReqClient := mockHTTPClient{
				resBody: testCase.inputRespBody,
				code:    testCase.inputCode,
			}
			config := KeycloakClientConfig{}

			creds := KeycloakCredentials{
				clientConfig: config,
				httpClient:   &jwtReqClient,
				helper:       testCase.helper,
			}

			resp, err := creds.requestJWTToken(context.Background())
			if err != nil {
				if testCase.expectedFuncExitErrDiff != nil {
					assert.EqualError(t, err, testCase.expectedFuncExitErrDiff.Error(), "errors should be the same")
				} else {
					t.Fatal(err)
				}
			} else {
				defer resp.Body.Close()
				body, err := io.ReadAll(resp.Body)
				assert.NoError(t, err, "unable to read the response body")

				jwtToken := JWTToken{}
				err = testCase.helper.Unmarshal(body, &jwtToken)
				assert.NoError(t, err, "unable to parse the json input")

				assert.Equalf(t, testCase.expectedToken, jwtToken.AccessToken, "two tokens should be the same")
			}
		})
	}
}

func TestKeycloakParseRequestJWTResponse(t *testing.T) {
	type parseRequestJWTResponseTest struct {
		name                 string
		inputRespBody        string
		helper               ManagerHelper
		expectedToken        string
		expectedExpiresIn    int
		assertErrFunc        assert.ErrorAssertionFunc
		assertErrFuncMessage string
	}

	exp := 100
	token := newTestJWT(t, exp)

	parseRequestJWTResponseTestCase1 := parseRequestJWTResponseTest{
		name:                 "Parse Good JWT Body",
		inputRespBody:        fmt.Sprintf("{\"access_token\":\"%s\",\"scope\":\"read:users\",\"expires_in\":%d,\"token_type\":\"Bearer\"}", token, exp),
		helper:               JsonParser{},
		expectedToken:        token,
		expectedExpiresIn:    exp,
		assertErrFunc:        assert.NoError,
		assertErrFuncMessage: "no error was expected",
	}
	parseRequestJWTResponseTestCase2 := parseRequestJWTResponseTest{
		name:                 "Parse Bad json JWT Body",
		inputRespBody:        "",
		helper:               JsonParser{},
		expectedToken:        "",
		expectedExpiresIn:    0,
		assertErrFunc:        assert.Error,
		assertErrFuncMessage: "json error was expected",
	}

	for _, testCase := range []parseRequestJWTResponseTest{parseRequestJWTResponseTestCase1, parseRequestJWTResponseTestCase2} {
		t.Run(testCase.name, func(t *testing.T) {
			rawBody := io.NopCloser(strings.NewReader(testCase.inputRespBody))
			config := KeycloakClientConfig{}

			creds := KeycloakCredentials{
				clientConfig: config,
				helper:       testCase.helper,
			}
			jwtToken, err := creds.parseRequestJWTResponse(rawBody)
			testCase.assertErrFunc(t, err, testCase.assertErrFuncMessage)

			assert.Equalf(t, testCase.expectedToken, jwtToken.AccessToken, "two tokens should be the same")
			assert.Equalf(t, testCase.expectedExpiresIn, jwtToken.ExpiresIn, "the two expire times should be the same")
		})
	}
}

func TestKeycloakJwtStillValid(t *testing.T) {
	type jwtStillValidTest struct {
		name           string
		inputTime      time.Time
		expectedResult bool
		message        string
	}

	jwtStillValidTestCase1 := jwtStillValidTest{
		name:           "JWT still valid",
		inputTime:      time.Now().Add(10 * time.Second),
		expectedResult: true,
		message:        "should be true",
	}
	jwtStillValidTestCase2 := jwtStillValidTest{
		name:           "JWT is invalid",
		inputTime:      time.Now(),
		expectedResult: false,
		message:        "should be false",
	}

	for _, testCase := range []jwtStillValidTest{jwtStillValidTestCase1, jwtStillValidTestCase2} {
		t.Run(testCase.name, func(t *testing.T) {
			config := KeycloakClientConfig{}

			creds := KeycloakCredentials{
				clientConfig: config,
			}
			creds.jwtToken.expiresInTime = testCase.inputTime

			assert.Equalf(t, testCase.expectedResult, creds.jwtStillValid(), testCase.message)
		})
	}
}

func TestKeycloakAuthenticate(t *testing.T) {
	type authenticateTest struct {
		name                    string
		inputCode               int
		inputResBody            string
		inputExpireToken        time.Time
		helper                  ManagerHelper
		expectedFuncExitErrDiff error
		expectedCode            int
		expectedToken           string
	}
	exp := 5
	token := newTestJWT(t, exp)

	authenticateTestCase1 := authenticateTest{
		name:                    "Get Cached token",
		inputExpireToken:        time.Now().Add(30 * time.Second),
		helper:                  JsonParser{},
		expectedFuncExitErrDiff: nil,
		expectedCode:            200,
		expectedToken:           "",
	}

	authenticateTestCase2 := authenticateTest{
		name:          "Get Good JWT Response",
		inputCode:     200,
		inputResBody:  fmt.Sprintf("{\"access_token\":\"%s\",\"scope\":\"read:users\",\"expires_in\":%d,\"token_type\":\"Bearer\"}", token, exp),
		helper:        JsonParser{},
		expectedCode:  200,
		expectedToken: token,
	}

	authenticateTestCase3 := authenticateTest{
		name:                    "Get Bad Status Code",
		inputCode:               400,
		inputResBody:            "{}",
		helper:                  JsonParser{},
		expectedFuncExitErrDiff: fmt.Errorf("unable to get keycloak token, statusCode 400"),
		expectedCode:            200,
		expectedToken:           "",
	}

	for _, testCase := range []authenticateTest{authenticateTestCase1, authenticateTestCase2, authenticateTestCase3} {
		t.Run(testCase.name, func(t *testing.T) {

			jwtReqClient := mockHTTPClient{
				resBody: testCase.inputResBody,
				code:    testCase.inputCode,
			}
			config := KeycloakClientConfig{}

			creds := KeycloakCredentials{
				clientConfig: config,
				httpClient:   &jwtReqClient,
				helper:       testCase.helper,
			}
			creds.jwtToken.expiresInTime = testCase.inputExpireToken

			_, err := creds.Authenticate(context.Background())
			if err != nil {
				if testCase.expectedFuncExitErrDiff != nil {
					assert.EqualError(t, err, testCase.expectedFuncExitErrDiff.Error(), "errors should be the same")
				} else {
					t.Fatal(err)
				}
			}

			assert.Equalf(t, testCase.expectedToken, creds.jwtToken.AccessToken, "two tokens should be the same")
		})
	}
}