package middlewares_test

import (
	"fmt"
	"testing"
	"time"

	"github.com/golang-jwt/jwt/v4"
	"github.com/golang/mock/gomock"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/suite"

	"github.com/authelia/authelia/internal/middlewares"
	"github.com/authelia/authelia/internal/mocks"
	"github.com/authelia/authelia/internal/session"
)

const testJWTSecret = "abc"

func newArgs(retriever func(ctx *middlewares.AutheliaCtx) (*session.Identity, error)) middlewares.IdentityVerificationStartArgs {
	return middlewares.IdentityVerificationStartArgs{
		ActionClaim:           "Claim",
		MailButtonContent:     "Register",
		MailTitle:             "Title",
		TargetEndpoint:        "/target",
		IdentityRetrieverFunc: retriever,
	}
}

func defaultRetriever(ctx *middlewares.AutheliaCtx) (*session.Identity, error) {
	return &session.Identity{
		Username: "john",
		Email:    "john@example.com",
	}, nil
}

func TestShouldFailStartingProcessIfUserHasNoEmailAddress(t *testing.T) {
	mock := mocks.NewMockAutheliaCtx(t)
	defer mock.Close()

	retriever := func(ctx *middlewares.AutheliaCtx) (*session.Identity, error) {
		return nil, fmt.Errorf("User does not have any email")
	}

	middlewares.IdentityVerificationStart(newArgs(retriever))(mock.Ctx)

	assert.Equal(t, 200, mock.Ctx.Response.StatusCode())
	assert.Equal(t, "User does not have any email", mock.Hook.LastEntry().Message)
}

func TestShouldFailIfJWTCannotBeSaved(t *testing.T) {
	mock := mocks.NewMockAutheliaCtx(t)
	defer mock.Close()

	mock.Ctx.Configuration.JWTSecret = testJWTSecret

	mock.StorageProviderMock.EXPECT().
		SaveIdentityVerificationToken(gomock.Any()).
		Return(fmt.Errorf("cannot save"))

	args := newArgs(defaultRetriever)
	middlewares.IdentityVerificationStart(args)(mock.Ctx)

	assert.Equal(t, 200, mock.Ctx.Response.StatusCode())
	assert.Equal(t, "cannot save", mock.Hook.LastEntry().Message)
}

func TestShouldFailSendingAnEmail(t *testing.T) {
	mock := mocks.NewMockAutheliaCtx(t)
	defer mock.Close()

	mock.Ctx.Configuration.JWTSecret = testJWTSecret
	mock.Ctx.Request.Header.Add("X-Forwarded-Proto", "http")
	mock.Ctx.Request.Header.Add("X-Forwarded-Host", "host")

	mock.StorageProviderMock.EXPECT().
		SaveIdentityVerificationToken(gomock.Any()).
		Return(nil)

	mock.NotifierMock.EXPECT().
		Send(gomock.Eq("john@example.com"), gomock.Eq("Title"), gomock.Any(), gomock.Any()).
		Return(fmt.Errorf("no notif"))

	args := newArgs(defaultRetriever)
	middlewares.IdentityVerificationStart(args)(mock.Ctx)

	assert.Equal(t, 200, mock.Ctx.Response.StatusCode())
	assert.Equal(t, "no notif", mock.Hook.LastEntry().Message)
}

func TestShouldFailWhenXForwardedProtoHeaderIsMissing(t *testing.T) {
	mock := mocks.NewMockAutheliaCtx(t)
	defer mock.Close()

	mock.Ctx.Configuration.JWTSecret = testJWTSecret
	mock.Ctx.Request.Header.Add("X-Forwarded-Host", "host")

	mock.StorageProviderMock.EXPECT().
		SaveIdentityVerificationToken(gomock.Any()).
		Return(nil)

	args := newArgs(defaultRetriever)
	middlewares.IdentityVerificationStart(args)(mock.Ctx)

	assert.Equal(t, 200, mock.Ctx.Response.StatusCode())
	assert.Equal(t, "Missing header X-Forwarded-Proto", mock.Hook.LastEntry().Message)
}

func TestShouldFailWhenXForwardedHostHeaderIsMissing(t *testing.T) {
	mock := mocks.NewMockAutheliaCtx(t)
	defer mock.Close()

	mock.Ctx.Configuration.JWTSecret = testJWTSecret
	mock.Ctx.Request.Header.Add("X-Forwarded-Proto", "http")

	mock.StorageProviderMock.EXPECT().
		SaveIdentityVerificationToken(gomock.Any()).
		Return(nil)

	args := newArgs(defaultRetriever)
	middlewares.IdentityVerificationStart(args)(mock.Ctx)

	assert.Equal(t, 200, mock.Ctx.Response.StatusCode())
	assert.Equal(t, "Missing header X-Forwarded-Host", mock.Hook.LastEntry().Message)
}

func TestShouldSucceedIdentityVerificationStartProcess(t *testing.T) {
	mock := mocks.NewMockAutheliaCtx(t)

	mock.Ctx.Configuration.JWTSecret = testJWTSecret
	mock.Ctx.Request.Header.Add("X-Forwarded-Proto", "http")
	mock.Ctx.Request.Header.Add("X-Forwarded-Host", "host")

	mock.StorageProviderMock.EXPECT().
		SaveIdentityVerificationToken(gomock.Any()).
		Return(nil)

	mock.NotifierMock.EXPECT().
		Send(gomock.Eq("john@example.com"), gomock.Eq("Title"), gomock.Any(), gomock.Any()).
		Return(nil)

	args := newArgs(defaultRetriever)
	middlewares.IdentityVerificationStart(args)(mock.Ctx)

	assert.Equal(t, 200, mock.Ctx.Response.StatusCode())

	defer mock.Close()
}

// Test Finish process.
type IdentityVerificationFinishProcess struct {
	suite.Suite

	mock *mocks.MockAutheliaCtx
}

func (s *IdentityVerificationFinishProcess) SetupTest() {
	s.mock = mocks.NewMockAutheliaCtx(s.T())

	s.mock.Ctx.Configuration.JWTSecret = testJWTSecret
}

func (s *IdentityVerificationFinishProcess) TearDownTest() {
	s.mock.Close()
}

func createToken(secret string, username string, action string, expiresAt time.Time) string {
	claims := &middlewares.IdentityVerificationClaim{
		jwt.StandardClaims{
			ExpiresAt: expiresAt.Unix(),
			Issuer:    "Authelia",
		},
		action,
		username,
	}
	token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
	ss, _ := token.SignedString([]byte(secret))

	return ss
}

func next(ctx *middlewares.AutheliaCtx, username string) {}

func newFinishArgs() middlewares.IdentityVerificationFinishArgs {
	return middlewares.IdentityVerificationFinishArgs{
		ActionClaim:          "EXP_ACTION",
		IsTokenUserValidFunc: func(ctx *middlewares.AutheliaCtx, username string) bool { return true },
	}
}

func (s *IdentityVerificationFinishProcess) TestShouldFailIfJSONBodyIsMalformed() {
	middlewares.IdentityVerificationFinish(newFinishArgs(), next)(s.mock.Ctx)

	s.mock.Assert200KO(s.T(), "Operation failed")
	assert.Equal(s.T(), "unexpected end of JSON input", s.mock.Hook.LastEntry().Message)
}

func (s *IdentityVerificationFinishProcess) TestShouldFailIfTokenIsNotProvided() {
	s.mock.Ctx.Request.SetBodyString("{}")
	middlewares.IdentityVerificationFinish(newFinishArgs(), next)(s.mock.Ctx)

	s.mock.Assert200KO(s.T(), "Operation failed")
	assert.Equal(s.T(), "No token provided", s.mock.Hook.LastEntry().Message)
}

func (s *IdentityVerificationFinishProcess) TestShouldFailIfTokenIsNotFoundInDB() {
	s.mock.Ctx.Request.SetBodyString("{\"token\":\"abc\"}")

	s.mock.StorageProviderMock.EXPECT().
		FindIdentityVerificationToken(gomock.Eq("abc")).
		Return(false, nil)

	middlewares.IdentityVerificationFinish(newFinishArgs(), next)(s.mock.Ctx)

	s.mock.Assert200KO(s.T(), "The identity verification token has already been used")
	assert.Equal(s.T(), "Token is not in DB, it might have already been used", s.mock.Hook.LastEntry().Message)
}

func (s *IdentityVerificationFinishProcess) TestShouldFailIfTokenIsInvalid() {
	s.mock.Ctx.Request.SetBodyString("{\"token\":\"abc\"}")

	s.mock.StorageProviderMock.EXPECT().
		FindIdentityVerificationToken(gomock.Eq("abc")).
		Return(true, nil)

	middlewares.IdentityVerificationFinish(newFinishArgs(), next)(s.mock.Ctx)

	s.mock.Assert200KO(s.T(), "Operation failed")
	assert.Equal(s.T(), "Cannot parse token", s.mock.Hook.LastEntry().Message)
}

func (s *IdentityVerificationFinishProcess) TestShouldFailIfTokenExpired() {
	args := newArgs(defaultRetriever)
	token := createToken(s.mock.Ctx.Configuration.JWTSecret, "john", args.ActionClaim,
		time.Now().Add(-1*time.Minute))
	s.mock.Ctx.Request.SetBodyString(fmt.Sprintf("{\"token\":\"%s\"}", token))

	s.mock.StorageProviderMock.EXPECT().
		FindIdentityVerificationToken(gomock.Eq(token)).
		Return(true, nil)

	middlewares.IdentityVerificationFinish(newFinishArgs(), next)(s.mock.Ctx)

	s.mock.Assert200KO(s.T(), "The identity verification token has expired")
	assert.Equal(s.T(), "Token expired", s.mock.Hook.LastEntry().Message)
}

func (s *IdentityVerificationFinishProcess) TestShouldFailForWrongAction() {
	token := createToken(s.mock.Ctx.Configuration.JWTSecret, "", "",
		time.Now().Add(1*time.Minute))
	s.mock.Ctx.Request.SetBodyString(fmt.Sprintf("{\"token\":\"%s\"}", token))

	s.mock.StorageProviderMock.EXPECT().
		FindIdentityVerificationToken(gomock.Eq(token)).
		Return(true, nil)

	middlewares.IdentityVerificationFinish(newFinishArgs(), next)(s.mock.Ctx)

	s.mock.Assert200KO(s.T(), "Operation failed")
	assert.Equal(s.T(), "This token has not been generated for this kind of action", s.mock.Hook.LastEntry().Message)
}

func (s *IdentityVerificationFinishProcess) TestShouldFailForWrongUser() {
	token := createToken(s.mock.Ctx.Configuration.JWTSecret, "harry", "EXP_ACTION",
		time.Now().Add(1*time.Minute))
	s.mock.Ctx.Request.SetBodyString(fmt.Sprintf("{\"token\":\"%s\"}", token))

	s.mock.StorageProviderMock.EXPECT().
		FindIdentityVerificationToken(gomock.Eq(token)).
		Return(true, nil)

	args := newFinishArgs()
	args.IsTokenUserValidFunc = func(ctx *middlewares.AutheliaCtx, username string) bool { return false }
	middlewares.IdentityVerificationFinish(args, next)(s.mock.Ctx)

	s.mock.Assert200KO(s.T(), "Operation failed")
	assert.Equal(s.T(), "This token has not been generated for this user", s.mock.Hook.LastEntry().Message)
}

func (s *IdentityVerificationFinishProcess) TestShouldFailIfTokenCannotBeRemovedFromDB() {
	token := createToken(s.mock.Ctx.Configuration.JWTSecret, "john", "EXP_ACTION",
		time.Now().Add(1*time.Minute))
	s.mock.Ctx.Request.SetBodyString(fmt.Sprintf("{\"token\":\"%s\"}", token))

	s.mock.StorageProviderMock.EXPECT().
		FindIdentityVerificationToken(gomock.Eq(token)).
		Return(true, nil)

	s.mock.StorageProviderMock.EXPECT().
		RemoveIdentityVerificationToken(gomock.Eq(token)).
		Return(fmt.Errorf("cannot remove"))

	middlewares.IdentityVerificationFinish(newFinishArgs(), next)(s.mock.Ctx)

	s.mock.Assert200KO(s.T(), "Operation failed")
	assert.Equal(s.T(), "cannot remove", s.mock.Hook.LastEntry().Message)
}

func (s *IdentityVerificationFinishProcess) TestShouldReturn200OnFinishComplete() {
	token := createToken(s.mock.Ctx.Configuration.JWTSecret, "john", "EXP_ACTION",
		time.Now().Add(1*time.Minute))
	s.mock.Ctx.Request.SetBodyString(fmt.Sprintf("{\"token\":\"%s\"}", token))

	s.mock.StorageProviderMock.EXPECT().
		FindIdentityVerificationToken(gomock.Eq(token)).
		Return(true, nil)

	s.mock.StorageProviderMock.EXPECT().
		RemoveIdentityVerificationToken(gomock.Eq(token)).
		Return(nil)

	middlewares.IdentityVerificationFinish(newFinishArgs(), next)(s.mock.Ctx)

	assert.Equal(s.T(), 200, s.mock.Ctx.Response.StatusCode())
}

func TestRunIdentityVerificationFinish(t *testing.T) {
	s := new(IdentityVerificationFinishProcess)
	suite.Run(t, s)
}