3 files changed, 166 insertions, 0 deletions
diff --git a/backend/internal/server/auth/callback/callback.go b/backend/internal/server/auth/callback/callback.go
new file mode 100644
index 0000000..f0a3413
--- /dev/null
+++ b/backend/internal/server/auth/callback/callback.go
@@ -0,0 +1,93 @@
+package callback
+
+import (
+	"context"
+	"log/slog"
+	"net/http"
+	"time"
+
+	"ibd-trader/internal/auth"
+	"ibd-trader/internal/database"
+	"ibd-trader/internal/server/middleware"
+)
+
+func Handler(
+	logger *slog.Logger,
+	userStore database.UserStore,
+	sessionStore database.SessionStore,
+	auth *auth.Authenticator,
+) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		// Timeout callback operations after 10 seconds
+		ctx, cancel := context.WithTimeout(r.Context(), 10*time.Second)
+		defer cancel()
+
+		// Check state
+		state := r.URL.Query().Get("state")
+		if state == "" {
+			http.Error(w, "No state provided", http.StatusBadRequest)
+			return
+		}
+
+		exists, err := sessionStore.CheckState(ctx, state)
+		if err != nil {
+			logger.ErrorContext(ctx, "Failed to check state", "error", err)
+			http.Error(w, "Failed to check state", http.StatusInternalServerError)
+			return
+		}
+		if !exists {
+			http.Error(w, "Invalid state", http.StatusBadRequest)
+			return
+		}
+
+		// Exchange code for token
+		token, err := auth.Exchange(ctx, r.URL.Query().Get("code"))
+		if err != nil {
+			logger.ErrorContext(ctx, "Failed to exchange code", "error", err)
+			http.Error(w, "Failed to exchange code", http.StatusUnauthorized)
+			return
+		}
+
+		// Verify token
+		idToken, err := auth.VerifyIDToken(ctx, token)
+		if err != nil {
+			logger.ErrorContext(ctx, "Failed to verify ID token", "error", err)
+			http.Error(w, "Failed to verify ID token", http.StatusInternalServerError)
+			return
+		}
+
+		// Add user to database
+		if err := userStore.AddUser(ctx, idToken.Subject); err != nil {
+			logger.ErrorContext(ctx, "Failed to add user", "error", err)
+			http.Error(w, "Failed to add user", http.StatusInternalServerError)
+			return
+		}
+
+		// Create session
+		session, err := sessionStore.CreateSession(ctx, token, idToken)
+		if err != nil {
+			logger.ErrorContext(ctx, "Failed to create session", "error", err)
+			http.Error(w, "Failed to create session", http.StatusInternalServerError)
+			return
+		}
+
+		// Set session cookie
+		http.SetCookie(w, &http.Cookie{
+			Name:       middleware.SessionCookie,
+			Value:      session,
+			Path:       "/",
+			Domain:     "",
+			Expires:    token.Expiry,
+			RawExpires: "",
+			MaxAge:     0,
+			Secure:     true,
+			HttpOnly:   true,
+			SameSite:   http.SameSiteLaxMode,
+			Raw:        "",
+			Unparsed:   nil,
+		})
+
+		// Redirect
+		http.Redirect(w, r, "/", http.StatusTemporaryRedirect)
+	}
+}
diff --git a/backend/internal/server/auth/login/login.go b/backend/internal/server/auth/login/login.go
new file mode 100644
index 0000000..102e3d4
--- /dev/null
+++ b/backend/internal/server/auth/login/login.go
@@ -0,0 +1,28 @@
+package login
+
+import (
+	"context"
+	"log/slog"
+	"net/http"
+	"time"
+
+	"ibd-trader/internal/auth"
+	"ibd-trader/internal/database"
+)
+
+func Handler(logger *slog.Logger, store database.SessionStore, auth *auth.Authenticator) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		// Save state in session table w/o user id
+		ctx, cancel := context.WithTimeout(r.Context(), 5*time.Second)
+		defer cancel()
+		state, err := store.CreateState(ctx)
+		if err != nil {
+			logger.ErrorContext(ctx, "Failed to create state", "error", err)
+			http.Error(w, "Failed to create state", http.StatusInternalServerError)
+			return
+		}
+
+		// Redirect to oauth provider
+		http.Redirect(w, r, auth.AuthCodeURL(state), http.StatusTemporaryRedirect)
+	}
+}
diff --git a/backend/internal/server/auth/user/user.go b/backend/internal/server/auth/user/user.go
new file mode 100644
index 0000000..526329d
--- /dev/null
+++ b/backend/internal/server/auth/user/user.go
@@ -0,0 +1,45 @@
+package user
+
+import (
+	"context"
+	"encoding/json"
+	"log/slog"
+	"net/http"
+	"time"
+
+	"ibd-trader/internal/auth"
+	"ibd-trader/internal/database"
+)
+
+func Handler(
+	logger *slog.Logger,
+	auth *auth.Authenticator,
+) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		ctx, cancel := context.WithTimeout(r.Context(), 10*time.Second)
+		defer cancel()
+
+		// Get session from context
+		session, ok := ctx.Value("session").(*database.Session)
+		if !ok {
+			http.Error(w, "Unauthorized", http.StatusUnauthorized)
+			return
+		}
+
+		// Create token source
+		ts := auth.TokenSource(ctx, &session.OAuthToken)
+
+		// Get user info
+		userInfo, err := auth.UserInfo(ctx, ts)
+		if err != nil {
+			logger.ErrorContext(ctx, "Failed to get user info", "error", err)
+			http.Error(w, "Failed to get user info", http.StatusInternalServerError)
+			return
+		}
+
+		// Write user info to response
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(http.StatusOK)
+		_ = json.NewEncoder(w).Encode(userInfo)
+	}
+}