Handlers: Add password confirmation validation to signup

- Server-side validation for password confirmation field
- Display error message if passwords don't match
- Complements client-side validation added in previous commit

handlers/signup.go

@@ -1,66 +1,94 @@
 package handlers
 
 import (
-    "log"
-    "net/http"
-    "threadr/models"
-    "github.com/gorilla/sessions"
+	"github.com/gorilla/sessions"
+	"log"
+	"net/http"
+	"threadr/models"
 )
 
 func SignupHandler(app *App) http.HandlerFunc {
-    return func(w http.ResponseWriter, r *http.Request) {
-        session := r.Context().Value("session").(*sessions.Session)
-        cookie, _ := r.Cookie("threadr_cookie_banner")
-        if r.Method == http.MethodPost {
-            username := r.FormValue("username")
-            password := r.FormValue("password")
-            err := models.CreateUser(app.DB, username, password)
-            if err != nil {
-                log.Printf("Error creating user: %v", err)
-                data := struct {
-                    PageData
-                    Error string
-                }{
-                    PageData: PageData{
-                        Title:            "ThreadR - Sign Up",
-                        Navbar:           "signup",
-                        LoggedIn:         false,
-                        ShowCookieBanner: cookie == nil || cookie.Value != "accepted",
-                        BasePath:         app.Config.ThreadrDir,
-                        StaticPath:       app.Config.ThreadrDir + "/static",
-                        CurrentURL:       r.URL.Path,
-                    },
-                    Error: "An error occurred during sign up. Please try again.",
-                }
-                if err := app.Tmpl.ExecuteTemplate(w, "signup", data); err != nil {
-                    log.Printf("Error executing template in SignupHandler: %v", err)
-                    http.Error(w, "Internal Server Error", http.StatusInternalServerError)
-                    return
-                }
-                return
-            }
-            http.Redirect(w, r, app.Config.ThreadrDir+"/login/", http.StatusFound)
-            return
-        }
-        data := struct {
-            PageData
-            Error string
-        }{
-            PageData: PageData{
-                Title:            "ThreadR - Sign Up",
-                Navbar:           "signup",
-                LoggedIn:         session.Values["user_id"] != nil,
-                ShowCookieBanner: cookie == nil || cookie.Value != "accepted",
-                BasePath:         app.Config.ThreadrDir,
-                StaticPath:       app.Config.ThreadrDir + "/static",
-                CurrentURL:       r.URL.Path,
-            },
-            Error: "",
-        }
-        if err := app.Tmpl.ExecuteTemplate(w, "signup", data); err != nil {
-            log.Printf("Error executing template in SignupHandler: %v", err)
-            http.Error(w, "Internal Server Error", http.StatusInternalServerError)
-            return
-        }
-    }
-}
+	return func(w http.ResponseWriter, r *http.Request) {
+		session := r.Context().Value("session").(*sessions.Session)
+		cookie, _ := r.Cookie("threadr_cookie_banner")
+		if r.Method == http.MethodPost {
+			username := r.FormValue("username")
+			password := r.FormValue("password")
+			passwordConfirm := r.FormValue("password_confirm")
+
+			// Server-side validation for password confirmation
+			if password != passwordConfirm {
+				log.Printf("Password confirmation mismatch for user: %s", username)
+				data := struct {
+					PageData
+					Error string
+				}{
+					PageData: PageData{
+						Title:            "ThreadR - Sign Up",
+						Navbar:           "signup",
+						LoggedIn:         false,
+						ShowCookieBanner: cookie == nil || cookie.Value != "accepted",
+						BasePath:         app.Config.ThreadrDir,
+						StaticPath:       app.Config.ThreadrDir + "/static",
+						CurrentURL:       r.URL.Path,
+					},
+					Error: "Passwords do not match. Please try again.",
+				}
+				if err := app.Tmpl.ExecuteTemplate(w, "signup", data); err != nil {
+					log.Printf("Error executing template in SignupHandler: %v", err)
+					http.Error(w, "Internal Server Error", http.StatusInternalServerError)
+					return
+				}
+				return
+			}
+
+			err := models.CreateUser(app.DB, username, password)
+			if err != nil {
+				log.Printf("Error creating user: %v", err)
+				data := struct {
+					PageData
+					Error string
+				}{
+					PageData: PageData{
+						Title:            "ThreadR - Sign Up",
+						Navbar:           "signup",
+						LoggedIn:         false,
+						ShowCookieBanner: cookie == nil || cookie.Value != "accepted",
+						BasePath:         app.Config.ThreadrDir,
+						StaticPath:       app.Config.ThreadrDir + "/static",
+						CurrentURL:       r.URL.Path,
+					},
+					Error: "An error occurred during sign up. Please try again.",
+				}
+				if err := app.Tmpl.ExecuteTemplate(w, "signup", data); err != nil {
+					log.Printf("Error executing template in SignupHandler: %v", err)
+					http.Error(w, "Internal Server Error", http.StatusInternalServerError)
+					return
+				}
+				return
+			}
+			http.Redirect(w, r, app.Config.ThreadrDir+"/login/", http.StatusFound)
+			return
+		}
+		data := struct {
+			PageData
+			Error string
+		}{
+			PageData: PageData{
+				Title:            "ThreadR - Sign Up",
+				Navbar:           "signup",
+				LoggedIn:         session.Values["user_id"] != nil,
+				ShowCookieBanner: cookie == nil || cookie.Value != "accepted",
+				BasePath:         app.Config.ThreadrDir,
+				StaticPath:       app.Config.ThreadrDir + "/static",
+				CurrentURL:       r.URL.Path,
+			},
+			Error: "",
+		}
+		if err := app.Tmpl.ExecuteTemplate(w, "signup", data); err != nil {
+			log.Printf("Error executing template in SignupHandler: %v", err)
+			http.Error(w, "Internal Server Error", http.StatusInternalServerError)
+			return
+		}
+	}
+}