package sessions

import (
	"encoding/base64"
	"encoding/json"
	"net/http"
	"net/url"
	"testing"

	"github.com/oauth2-proxy/mockoidc"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
	"github.com/xlgmokha/x/pkg/x"
	"gitlab.com/gitlab-org/software-supply-chain-security/authorization/sparkled/pkg/oidc"
	"gitlab.com/gitlab-org/software-supply-chain-security/authorization/sparkled/pkg/test"
)

func TestSessions(t *testing.T) {
	srv := test.NewOIDCServer(t)
	defer srv.Close()

	clientID := srv.MockOIDC.Config().ClientID
	clientSecret := srv.MockOIDC.Config().ClientSecret
	cfg, err := oidc.New(
		t.Context(),
		srv.Issuer(),
		clientID,
		clientSecret,
		"callback_url",
	)
	require.NoError(t, err)
	controller := New(cfg, http.DefaultClient)
	mux := http.NewServeMux()
	controller.MountTo(mux)

	t.Run("GET /session/new", func(t *testing.T) {
		t.Run("without an authenticated session", func(t *testing.T) {
			t.Run("redirect to the OIDC Provider", func(t *testing.T) {
				r, w := test.RequestResponse("GET", "/session/new")

				mux.ServeHTTP(w, r)

				require.Equal(t, http.StatusFound, w.Code)
				require.NotEmpty(t, w.Header().Get("Location"))
				redirectURL, err := url.Parse(w.Header().Get("Location"))
				require.NoError(t, err)
				assert.Equal(t, srv.AuthorizationEndpoint(), redirectURL.Scheme+"://"+redirectURL.Host+redirectURL.Path)
				assert.NotEmpty(t, redirectURL.Query().Get("state"))
				assert.Equal(t, srv.MockOIDC.Config().ClientID, redirectURL.Query().Get("client_id"))
				assert.Equal(t, "openid profile email", redirectURL.Query().Get("scope"))
				assert.Equal(t, "todo", redirectURL.Query().Get("audience"))
				assert.Equal(t, cfg.Config.RedirectURL, redirectURL.Query().Get("redirect_uri"))
				assert.Equal(t, "code", redirectURL.Query().Get("response_type"))
			})

			t.Run("generates a CSRF token", func(t *testing.T) {})
		})

		t.Run("with an active authenicated session", func(t *testing.T) {})
		t.Run("with an expired authenicated session", func(t *testing.T) {})
	})

	t.Run("GET /session/callback", func(t *testing.T) {
		t.Run("with an invalid csrf token", func(t *testing.T) {})
		t.Run("with an invalid authorization code grant", func(t *testing.T) {
			r, w := test.RequestResponse("GET", "/session/callback?code=invalid")

			mux.ServeHTTP(w, r)

			assert.Equal(t, http.StatusBadRequest, w.Code)
		})

		t.Run("with a valid authorization code grant", func(t *testing.T) {
			user := mockoidc.DefaultUser()
			code := srv.CreateAuthorizationCodeFor(user)

			r, w := test.RequestResponse("GET", "/session/callback?code="+code)

			mux.ServeHTTP(w, r)

			cookies, err := http.ParseCookie(w.Header().Get("Set-Cookie"))
			require.NoError(t, err)
			cookie := x.Find(cookies, func(item *http.Cookie) bool {
				return item.Name == "session"
			})
			require.NotZero(t, cookie)
			data, err := base64.URLEncoding.DecodeString(cookie.Value)
			require.NoError(t, err)
			tokens := map[string]interface{}{}
			require.NoError(t, json.Unmarshal(data, &tokens))

			t.Run("stores the id token in a session cookie", func(t *testing.T) {
				require.NotEmpty(t, tokens["id_token"])

				idToken := srv.Verify(tokens["id_token"].(string))
				assert.Equal(t, user.Subject, idToken.Subject)
			})

			t.Run("stores the access token in a session cookie", func(t *testing.T) {
				assert.NotEmpty(t, tokens["access_token"])
				assert.Equal(t, "bearer", tokens["token_type"])

				keypair, err := mockoidc.DefaultKeypair()
				require.NoError(t, err)

				token, err := keypair.VerifyJWT(tokens["access_token"].(string), nil)
				require.NoError(t, err)

				sub, err := token.Claims.GetSubject()
				require.NoError(t, err)
				assert.Equal(t, user.Subject, sub)
			})

			t.Run("stores the refresh token in a session cookie", func(t *testing.T) {
				assert.NotEmpty(t, tokens["refresh_token"])

				keypair, err := mockoidc.DefaultKeypair()
				require.NoError(t, err)

				token, err := keypair.VerifyJWT(tokens["refresh_token"].(string), nil)
				require.NoError(t, err)

				sub, err := token.Claims.GetSubject()
				require.NoError(t, err)
				assert.Equal(t, user.Subject, sub)
			})

			t.Run("redirects to the homepage", func(t *testing.T) {
				require.Equal(t, http.StatusFound, w.Code)
				assert.Equal(t, "/dashboard", w.Header().Get("Location"))
			})
		})
	})
}