...

src/app/auth/AuthForm.tsx

@@ -6,7 +6,7 @@ import { Container } from "@/components/ui/Container";
 import { Input } from "@/components/ui/Input";
 import { LightButton } from "@/components/ui/buttons";
 import { authClient } from "@/lib/auth-client";
-import { signInAction, signUpAction, SignUpState } from "@/modules/auth/auth-action";
+import { actionSignIn, actionSignUp, ActionOutputAuth } from "@/modules/auth/auth-action";
 
 interface AuthFormProps {
   redirectTo?: string;
@@ -19,22 +19,22 @@ export function AuthForm({ redirectTo }: AuthFormProps) {
   const [clearSignUp, setClearSignUp] = useState(false);
 
   const [signInState, signInActionForm, isSignInPending] = useActionState(
-    async (prevState: SignUpState | undefined, formData: FormData) => {
+    async (_prevState: ActionOutputAuth | undefined, formData: FormData) => {
       if (clearSignIn) {
         setClearSignIn(false);
         return undefined;
       }
-      return signInAction(prevState || {}, formData);
+      return actionSignIn(undefined, formData);
     },
     undefined
   );
   const [signUpState, signUpActionForm, isSignUpPending] = useActionState(
-    async (prevState: SignUpState | undefined, formData: FormData) => {
+    async (_prevState: ActionOutputAuth | undefined, formData: FormData) => {
       if (clearSignUp) {
         setClearSignUp(false);
         return undefined;
       }
-      return signUpAction(prevState || {}, formData);
+      return actionSignUp(undefined, formData);
     },
     undefined
   );
@@ -44,15 +44,32 @@ export function AuthForm({ redirectTo }: AuthFormProps) {
   const validateForm = (formData: FormData): boolean => {
     const newErrors: Record<string, string> = {};
 
+    const identifier = formData.get("identifier") as string;
     const email = formData.get("email") as string;
+    const username = formData.get("username") as string;
     const password = formData.get("password") as string;
-    const name = formData.get("name") as string;
     const confirmPassword = formData.get("confirmPassword") as string;
 
-    if (!email) {
-      newErrors.email = t("emailRequired");
-    } else if (!/^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(email)) {
-      newErrors.email = t("invalidEmail");
+    // 登录模式验证
+    if (mode === 'signin') {
+      if (!identifier) {
+        newErrors.identifier = t("identifierRequired");
+      }
+    } else {
+      // 注册模式验证
+      if (!email) {
+        newErrors.email = t("emailRequired");
+      } else if (!/^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(email)) {
+        newErrors.email = t("invalidEmail");
+      }
+
+      if (!username) {
+        newErrors.username = t("usernameRequired");
+      } else if (username.length < 3) {
+        newErrors.username = t("usernameTooShort");
+      } else if (!/^[a-zA-Z0-9_]+$/.test(username)) {
+        newErrors.username = t("usernameInvalid");
+      }
     }
 
     if (!password) {
@@ -62,10 +79,6 @@ export function AuthForm({ redirectTo }: AuthFormProps) {
     }
 
     if (mode === 'signup') {
-      if (!name) {
-        newErrors.name = t("nameRequired");
-      }
-
       if (!confirmPassword) {
         newErrors.confirmPassword = t("confirmPasswordRequired");
       } else if (password !== confirmPassword) {
@@ -128,41 +141,57 @@ export function AuthForm({ redirectTo }: AuthFormProps) {
 
         {/* 登录/注册表单 */}
         <form onSubmit={handleFormSubmit} className="space-y-4">
-          {/* 用户名输入（仅注册模式显示） */}
-          {mode === 'signup' && (
+          {/* 邮箱/用户名输入（登录模式）或 用户名输入（注册模式） */}
+          {mode === 'signin' ? (
             <div>
               <Input
                 type="text"
-                name="name"
-                placeholder={t("name")}
+                name="identifier"
+                placeholder={t("emailOrUsername")}
                 className="w-full px-3 py-2"
               />
-              {/* 客户端验证错误 */}
-              {errors.name && (
-                <p className="text-red-500 text-sm mt-1">{errors.name}</p>
+              {errors.identifier && (
+                <p className="text-red-500 text-sm mt-1">{errors.identifier}</p>
               )}
-              {/* 服务器端验证错误 */}
-              {currentError?.errors?.username && (
-                <p className="text-red-500 text-sm mt-1">{currentError.errors.username[0]}</p>
+              {currentError?.errors?.email && (
+                <p className="text-red-500 text-sm mt-1">{currentError.errors.email[0]}</p>
               )}
             </div>
-          )}
+          ) : (
+            <>
+              {/* 用户名输入（仅注册模式） */}
+              <div>
+                <Input
+                  type="text"
+                  name="username"
+                  placeholder={t("username")}
+                  className="w-full px-3 py-2"
+                />
+                {errors.username && (
+                  <p className="text-red-500 text-sm mt-1">{errors.username}</p>
+                )}
+                {currentError?.errors?.username && (
+                  <p className="text-red-500 text-sm mt-1">{currentError.errors.username[0]}</p>
+                )}
+              </div>
 
-          {/* 邮箱输入 */}
-          <div>
-            <Input
-              type="email"
-              name="email"
-              placeholder={t("email")}
-              className="w-full px-3 py-2"
-            />
-            {errors.email && (
-              <p className="text-red-500 text-sm mt-1">{errors.email}</p>
-            )}
-            {currentError?.errors?.email && (
-              <p className="text-red-500 text-sm mt-1">{currentError.errors.email[0]}</p>
-            )}
-          </div>
+              {/* 邮箱输入（仅注册模式） */}
+              <div>
+                <Input
+                  type="email"
+                  name="email"
+                  placeholder={t("email")}
+                  className="w-full px-3 py-2"
+                />
+                {errors.email && (
+                  <p className="text-red-500 text-sm mt-1">{errors.email}</p>
+                )}
+                {currentError?.errors?.email && (
+                  <p className="text-red-500 text-sm mt-1">{currentError.errors.email[0]}</p>
+                )}
+              </div>
+            </>
+          )}
 
           {/* 密码输入 */}
           <div>
@@ -256,4 +285,4 @@ export function AuthForm({ redirectTo }: AuthFormProps) {
       </Container>
     </div>
   );
-}
+}

src/app/users/[username]/page.ts

@@ -0,0 +1,8 @@
+interface UserPageProps {
+    params: Promise<{ username: string}>;
+}
+
+export default async function UserPage({params}: UserPageProps) {
+    const {username} = await params;
+    
+}

src/auth.ts

@@ -2,6 +2,7 @@ import { betterAuth } from "better-auth";
 import { prismaAdapter } from "better-auth/adapters/prisma";
 import { nextCookies } from "better-auth/next-js";
 import { prisma } from "./lib/db";
+import { username } from "better-auth/plugins";
 
 export const auth = betterAuth({
     database: prismaAdapter(prisma, {
@@ -16,5 +17,5 @@ export const auth = betterAuth({
             clientSecret: process.env.GITHUB_CLIENT_SECRET as string
         },
     },
-    plugins: [nextCookies()]
+    plugins: [nextCookies(), username()]
 });

src/lib/auth-client.ts

@@ -1,5 +1,9 @@
+import { usernameClient } from "better-auth/client/plugins";
 import { createAuthClient } from "better-auth/react";
 
 export const authClient = createAuthClient({
-    baseURL: process.env.BETTER_AUTH_URL as string
+    baseURL: process.env.BETTER_AUTH_URL as string,
+    plugins: [
+        usernameClient()
+    ]
 });

src/modules/auth/auth-action-dto.ts

@@ -0,0 +1,47 @@
+import z from "zod";
+import { generateValidator } from "@/utils/validate";
+import { LENGTH_MAX_PASSWORD, LENGTH_MAX_USERNAME, LENGTH_MIN_PASSWORD, LENGTH_MIN_USERNAME } from "@/shared/constant";
+
+// Schema for sign up
+const schemaActionInputSignUp = z.object({
+    email: z.string().regex(/^[^\s@]+@[^\s@]+\.[^\s@]+$/, "Invalid email address"),
+    username: z.string().min(LENGTH_MIN_USERNAME).max(LENGTH_MAX_USERNAME).regex(/^[a-zA-Z0-9_]+$/, "Username can only contain letters, numbers, and underscores"),
+    password: z.string().min(LENGTH_MIN_PASSWORD).max(LENGTH_MAX_PASSWORD),
+    redirectTo: z.string().nullish(),
+});
+
+export type ActionInputSignUp = z.infer<typeof schemaActionInputSignUp>;
+
+export const validateActionInputSignUp = generateValidator(schemaActionInputSignUp);
+
+// Schema for sign in
+const schemaActionInputSignIn = z.object({
+    identifier: z.string().min(1), // Can be email or username
+    password: z.string().min(LENGTH_MIN_PASSWORD).max(LENGTH_MAX_PASSWORD),
+    redirectTo: z.string().nullish(),
+});
+
+export type ActionInputSignIn = z.infer<typeof schemaActionInputSignIn>;
+
+export const validateActionInputSignIn = generateValidator(schemaActionInputSignIn);
+
+// Schema for sign out
+const schemaActionInputSignOut = z.object({
+    redirectTo: z.string().nullish(),
+});
+
+export type ActionInputSignOut = z.infer<typeof schemaActionInputSignOut>;
+
+export const validateActionInputSignOut = generateValidator(schemaActionInputSignOut);
+
+// Output types
+export type ActionOutputAuth = {
+    success: boolean;
+    message: string;
+    errors?: {
+        username?: string[];
+        email?: string[];
+        password?: string[];
+        identifier?: string[];
+    };
+};

src/modules/auth/auth-action.ts

@@ -3,131 +3,144 @@
 import { auth } from "@/auth";
 import { headers } from "next/headers";
 import { redirect } from "next/navigation";
+import { ValidateError } from "@/lib/errors";
+import {
+    ActionInputSignIn,
+    ActionInputSignUp,
+    ActionOutputAuth,
+    validateActionInputSignIn,
+    validateActionInputSignUp
+} from "./auth-action-dto";
+import {
+    serviceSignIn,
+    serviceSignUp
+} from "./auth-service";
 
-export interface SignUpFormData {
-    username: string;
-    email: string;
-    password: string;
-}
-
-export interface SignUpState {
-    success?: boolean;
-    message?: string;
-    errors?: {
-        username?: string[];
-        email?: string[];
-        password?: string[];
-    };
-}
-
-export async function signUpAction(prevState: SignUpState, formData: FormData) {
-    const email = formData.get("email") as string;
-    const name = formData.get("name") as string;
-    const password = formData.get("password") as string;
-    const redirectTo = formData.get("redirectTo") as string;
-
-    // 服务器端验证
-    const errors: SignUpState['errors'] = {};
-
-    if (!email) {
-        errors.email = ["邮箱是必填项"];
-    } else if (!/^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(email)) {
-        errors.email = ["请输入有效的邮箱地址"];
-    }
-
-    if (!name) {
-        errors.username = ["姓名是必填项"];
-    } else if (name.length < 2) {
-        errors.username = ["姓名至少需要2个字符"];
-    }
-
-    if (!password) {
-        errors.password = ["密码是必填项"];
-    } else if (password.length < 8) {
-        errors.password = ["密码至少需要8个字符"];
-    }
-
-    // 如果有验证错误，返回错误状态
-    if (Object.keys(errors).length > 0) {
-        return {
-            success: false,
-            message: "请修正表单中的错误",
-            errors
-        };
-    }
+// Re-export types for use in components
+export type { ActionOutputAuth } from "./auth-action-dto";
 
+/**
+ * Sign up action
+ * Creates a new user account
+ */
+export async function actionSignUp(prevState: ActionOutputAuth | undefined, formData: FormData): Promise<ActionOutputAuth> {
     try {
-        await auth.api.signUpEmail({
-            body: {
-                email,
-                password,
-                name
-            }
+        // Extract form data
+        const rawData = {
+            email: formData.get("email") as string,
+            username: formData.get("username") as string,
+            password: formData.get("password") as string,
+            redirectTo: formData.get("redirectTo") as string | undefined,
+        };
+
+        // Validate input
+        const dto: ActionInputSignUp = validateActionInputSignUp(rawData);
+
+        // Call service layer
+        const result = await serviceSignUp({
+            email: dto.email,
+            username: dto.username,
+            password: dto.password,
+            name: dto.username,
         });
 
-        redirect(redirectTo || "/");
-    } catch (error) {
-        if (error instanceof Error && error.message.includes('NEXT_REDIRECT')) {
-            throw error;
+        if (!result.success) {
+            return {
+                success: false,
+                message: "Registration failed. Email or username may already be taken.",
+            };
         }
+
+        // Redirect on success
+        redirect(dto.redirectTo || "/");
+
+    } catch (e) {
+        if (e instanceof Error && e.message.includes('NEXT_REDIRECT')) {
+            throw e;
+        }
+        if (e instanceof ValidateError) {
+            return {
+                success: false,
+                message: e.message,
+            };
+        }
+        console.error("Sign up error:", e);
         return {
             success: false,
-            message: "注册失败，请稍后再试"
+            message: "Registration failed. Please try again later.",
         };
     }
 }
 
-export async function signInAction(prevState: SignUpState, formData: FormData) {
-    const email = formData.get("email") as string;
-    const password = formData.get("password") as string;
-    const redirectTo = formData.get("redirectTo") as string;
-
-    // 服务器端验证
-    const errors: SignUpState['errors'] = {};
-
-    if (!email) {
-        errors.email = ["邮箱是必填项"];
-    } else if (!/^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(email)) {
-        errors.email = ["请输入有效的邮箱地址"];
-    }
-
-    if (!password) {
-        errors.password = ["密码是必填项"];
-    }
-
-    // 如果有验证错误，返回错误状态
-    if (Object.keys(errors).length > 0) {
-        return {
-            success: false,
-            message: "请修正表单中的错误",
-            errors
-        };
-    }
-
+/**
+ * Sign in action
+ * Authenticates a user
+ */
+export async function actionSignIn(_prevState: ActionOutputAuth | undefined, formData: FormData): Promise<ActionOutputAuth> {
     try {
-        await auth.api.signInEmail({
-            body: {
-                email,
-                password,
-            }
+        // Extract form data
+        const rawData = {
+            identifier: formData.get("identifier") as string,
+            password: formData.get("password") as string,
+            redirectTo: formData.get("redirectTo") as string | undefined,
+        };
+
+        // Validate input
+        const dto: ActionInputSignIn = validateActionInputSignIn(rawData);
+
+        // Call service layer
+        const result = await serviceSignIn({
+            identifier: dto.identifier,
+            password: dto.password,
         });
 
-        redirect(redirectTo || "/");
-    } catch (error) {
-        if (error instanceof Error && error.message.includes('NEXT_REDIRECT')) {
-            throw error;
+        if (!result.success) {
+            return {
+                success: false,
+                message: "Invalid email/username or password.",
+                errors: {
+                    identifier: ["Invalid email/username or password"],
+                },
+            };
         }
+
+        // Redirect on success
+        redirect(dto.redirectTo || "/");
+
+    } catch (e) {
+        if (e instanceof Error && e.message.includes('NEXT_REDIRECT')) {
+            throw e;
+        }
+        if (e instanceof ValidateError) {
+            return {
+                success: false,
+                message: e.message,
+            };
+        }
+        console.error("Sign in error:", e);
         return {
             success: false,
-            message: "登录失败，请检查您的邮箱和密码"
+            message: "Sign in failed. Please check your credentials.",
         };
     }
 }
 
+/**
+ * Sign out action
+ * Signs out the current user
+ */
 export async function signOutAction() {
-    await auth.api.signOut({
-        headers: await headers()
-    });
+    try {
+        await auth.api.signOut({
+            headers: await headers()
+        });
 
-    redirect("/auth");
+        redirect("/auth");
+    } catch (e) {
+        if (e instanceof Error && e.message.includes('NEXT_REDIRECT')) {
+            throw e;
+        }
+        console.error("Sign out error:", e);
+        redirect("/auth");
+    }
 }

src/modules/auth/auth-service-dto.ts

@@ -0,0 +1,50 @@
+// Service layer DTOs for auth module
+
+// Sign up input/output
+export type ServiceInputSignUp = {
+    email: string;
+    username: string;
+    password: string; // plain text, will be hashed by better-auth
+    name: string;
+};
+
+export type ServiceOutputSignUp = {
+    success: boolean;
+    userId?: string;
+    email?: string;
+    username?: string;
+};
+
+// Sign in input/output
+export type ServiceInputSignIn = {
+    identifier: string; // email or username
+    password: string;
+};
+
+export type ServiceOutputSignIn = {
+    success: boolean;
+    userId?: string;
+    email?: string;
+    username?: string;
+    sessionToken?: string;
+};
+
+// Sign out input/output
+export type ServiceInputSignOut = {
+    sessionId?: string;
+};
+
+export type ServiceOutputSignOut = {
+    success: boolean;
+};
+
+// User existence check
+export type ServiceInputCheckUserExists = {
+    email?: string;
+    username?: string;
+};
+
+export type ServiceOutputCheckUserExists = {
+    emailExists: boolean;
+    usernameExists: boolean;
+};

src/modules/auth/auth-service.ts

@@ -0,0 +1,76 @@
+import { auth } from "@/auth";
+import {
+    ServiceInputSignUp,
+    ServiceInputSignIn,
+    ServiceOutputSignUp,
+    ServiceOutputSignIn
+} from "./auth-service-dto";
+
+/**
+ * Sign up a new user
+ * Calls better-auth's signUp.email with username support
+ */
+export async function serviceSignUp(dto: ServiceInputSignUp): Promise<ServiceOutputSignUp> {
+    try {
+        await auth.api.signUpEmail({
+            body: {
+                email: dto.email,
+                password: dto.password,
+                username: dto.username,
+                name: dto.name,
+            }
+        });
+
+        return {
+            success: true,
+            email: dto.email,
+            username: dto.username,
+        };
+    } catch (error) {
+        // better-auth handles duplicates and validation errors
+        return {
+            success: false,
+        };
+    }
+}
+
+/**
+ * Sign in user
+ * Uses better-auth's signIn.username for username-based authentication
+ */
+export async function serviceSignIn(dto: ServiceInputSignIn): Promise<ServiceOutputSignIn> {
+    try {
+        // Determine if identifier is email or username
+        const isEmail = /^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(dto.identifier);
+
+        let session;
+
+        if (isEmail) {
+            // Use email sign in
+            session = await auth.api.signInEmail({
+                body: {
+                    email: dto.identifier,
+                    password: dto.password,
+                }
+            });
+        } else {
+            // Use username sign in (requires username plugin)
+            session = await auth.api.signInUsername({
+                body: {
+                    username: dto.identifier,
+                    password: dto.password,
+                }
+            });
+        }
+
+        return {
+            success: true,
+            sessionToken: session?.token,
+        };
+    } catch (error) {
+        // better-auth throws on invalid credentials
+        return {
+            success: false,
+        };
+    }
+}

src/shared/constant.ts

@@ -14,4 +14,9 @@ export const LENGTH_MAX_FOLDER_NAME = 20;
 export const LENGTH_MIN_FOLDER_NAME = 1;
 
 export const LENGTH_MAX_TRANSLATOR_TEXT = 1000;
-export const LENGTH_MIN_TRANSLATOR_TEXT = 1;
+export const LENGTH_MIN_TRANSLATOR_TEXT = 1;
+
+export const LENGTH_MAX_USERNAME = 30;
+export const LENGTH_MIN_USERNAME = 3;
+export const LENGTH_MAX_PASSWORD = 100;
+export const LENGTH_MIN_PASSWORD = 8;