backend/database.py

@@ -165,6 +165,8 @@ def init_db():
         c.execute("ALTER TABLE users ADD COLUMN brand_align TEXT DEFAULT 'center'")
     if "role_changed_at" not in user_cols:
         c.execute("ALTER TABLE users ADD COLUMN role_changed_at TEXT")
+    if "username_changed" not in user_cols:
+        c.execute("ALTER TABLE users ADD COLUMN username_changed INTEGER DEFAULT 0")
 
     # Migration: add tags to user_diary
     diary_cols = [row[1] for row in c.execute("PRAGMA table_info(user_diary)").fetchall()]

backend/main.py

@@ -63,7 +63,7 @@ def get_current_user(request: Request):
     if not token:
         return ANON_USER
     conn = get_db()
-    user = conn.execute("SELECT id, username, role, display_name, password, business_verified FROM users WHERE token = ?", (token,)).fetchone()
+    user = conn.execute("SELECT id, username, role, display_name, password, business_verified, username_changed FROM users WHERE token = ?", (token,)).fetchone()
     conn.close()
     if not user:
         return ANON_USER
@@ -132,7 +132,7 @@ def get_version():
 
 @app.get("/api/me")
 def get_me(user=Depends(get_current_user)):
-    return {"username": user["username"], "role": user["role"], "display_name": user.get("display_name", ""), "id": user.get("id"), "has_password": bool(user.get("password")), "business_verified": bool(user.get("business_verified"))}
+    return {"username": user["username"], "role": user["role"], "display_name": user["username"], "id": user.get("id"), "has_password": bool(user.get("password")), "business_verified": bool(user.get("business_verified")), "username_changed": bool(user.get("username_changed"))}
 
 
 # ── Bug Reports ─────────────────────────────────────────
@@ -350,20 +350,24 @@ def symptom_search(body: dict, user=Depends(get_current_user)):
 def register(body: dict):
     username = body.get("username", "").strip()
     password = body.get("password", "").strip()
-    display_name = body.get("display_name", "").strip()
     if not username or len(username) < 2:
         raise HTTPException(400, "用户名至少2个字符")
     if not password or len(password) < 4:
         raise HTTPException(400, "密码至少4位")
-    token = _secrets.token_hex(24)
+    # Case-insensitive uniqueness check
     conn = get_db()
+    existing = conn.execute("SELECT id FROM users WHERE LOWER(username) = LOWER(?)", (username,)).fetchone()
+    if existing:
+        conn.close()
+        raise HTTPException(400, "用户名已被占用")
+    token = _secrets.token_hex(24)
     try:
         conn.execute(
             "INSERT INTO users (username, token, role, display_name, password) VALUES (?, ?, ?, ?, ?)",
-            (username, token, "viewer", display_name or username, hash_password(password))
+            (username, token, "viewer", username, hash_password(password))
         )
         uid = conn.execute("SELECT id FROM users WHERE username = ?", (username,)).fetchone()
-        log_audit(conn, uid["id"] if uid else None, "register", "user", username, display_name or username, None)
+        log_audit(conn, uid["id"] if uid else None, "register", "user", username, username, None)
         conn.commit()
     except Exception:
         conn.close()
@@ -380,7 +384,7 @@ def login(body: dict):
     if not username or not password:
         raise HTTPException(400, "请输入用户名和密码")
     conn = get_db()
-    user = conn.execute("SELECT id, token, password, display_name, role FROM users WHERE username = ?", (username,)).fetchone()
+    user = conn.execute("SELECT id, token, password, display_name, role, username FROM users WHERE LOWER(username) = LOWER(?)", (username,)).fetchone()
     if not user:
         conn.close()
         raise HTTPException(401, "用户名不存在")
@@ -452,6 +456,30 @@ def set_password(body: dict, user=Depends(get_current_user)):
     return {"ok": True}
 
 
+@app.put("/api/me/username")
+def change_username(body: dict, user=Depends(get_current_user)):
+    if not user["id"]:
+        raise HTTPException(403, "请先登录")
+    conn = get_db()
+    u = conn.execute("SELECT username_changed FROM users WHERE id = ?", (user["id"],)).fetchone()
+    if u and u["username_changed"]:
+        conn.close()
+        raise HTTPException(400, "用户名只能修改一次")
+    new_name = body.get("username", "").strip()
+    if not new_name or len(new_name) < 2:
+        conn.close()
+        raise HTTPException(400, "用户名至少2个字符")
+    existing = conn.execute("SELECT id FROM users WHERE LOWER(username) = LOWER(?) AND id != ?", (new_name, user["id"])).fetchone()
+    if existing:
+        conn.close()
+        raise HTTPException(400, "用户名已被占用")
+    conn.execute("UPDATE users SET username = ?, display_name = ?, username_changed = 1 WHERE id = ?",
+                 (new_name, new_name, user["id"]))
+    conn.commit()
+    conn.close()
+    return {"ok": True, "username": new_name}
+
+
 # ── Business Verification ──────────────────────────────
 @app.post("/api/business-apply", status_code=201)
 def business_apply(body: dict, user=Depends(get_current_user)):
@@ -1583,6 +1611,8 @@ def recipes_by_inventory(user=Depends(get_current_user)):
     return result
 
 
+
+# ── Search Logging ─────────────────────────────────────
 # ── Search Logging ─────────────────────────────────────
 @app.post("/api/search-log")
 def log_search(body: dict, user=Depends(get_current_user)):
@@ -1864,6 +1894,26 @@ def startup():
             data = json.load(f)
         seed_defaults(data["oils_meta"], data["recipes"])
 
+    # One-time migration: sync display_name = username, notify about username change
+    conn = get_db()
+    needs_sync = conn.execute("SELECT id, username, display_name FROM users WHERE display_name != username AND display_name IS NOT NULL").fetchall()
+    if needs_sync:
+        for row in needs_sync:
+            conn.execute("UPDATE users SET display_name = ? WHERE id = ?", (row["username"], row["id"]))
+        # Send notification once (check if already sent)
+        already_notified = conn.execute("SELECT id FROM notifications WHERE title = '📢 用户名变更通知'").fetchone()
+        if not already_notified:
+            all_users = conn.execute("SELECT id FROM users").fetchall()
+            for u in all_users:
+                conn.execute(
+                    "INSERT INTO notifications (target_role, title, body, target_user_id) VALUES (?, ?, ?, ?)",
+                    ("viewer", "📢 用户名更新提醒",
+                     "为了统一体验，系统已将显示名称合并为用户名。你有一次修改用户名的机会，修改后将不可更改，请慎重选择。", u["id"])
+                )
+        conn.commit()
+        print(f"[INIT] Synced display_name for {len(needs_sync)} users")
+    conn.close()
+
     # Auto-fill missing en_name for existing recipes
     conn = get_db()
     missing = conn.execute("SELECT id, name FROM recipes WHERE en_name IS NULL OR en_name = ''").fetchall()

frontend/cypress/e2e/pr27-features.cy.js

@@ -266,4 +266,396 @@ describe('PR27 Feature Tests', () => {
       cy.contains('登录 / 注册').should('be.visible')
     })
   })
+
+  // -------------------------------------------------------------------------
+  // API: Case-insensitive username registration
+  // -------------------------------------------------------------------------
+  describe('API: case-insensitive username registration', () => {
+    const CASE_USER = 'CypressCaseTest'
+    const CASE_PASS = 'test1234'
+
+    // Cleanup before test
+    before(() => {
+      cy.request({ url: '/api/users', headers: authHeaders }).then(res => {
+        const leftover = res.body.find(u =>
+          u.username.toLowerCase() === CASE_USER.toLowerCase()
+        )
+        if (leftover) {
+          cy.request({
+            method: 'DELETE',
+            url: `/api/users/${leftover.id || leftover._id}`,
+            headers: authHeaders,
+            failOnStatusCode: false,
+          })
+        }
+      })
+    })
+
+    after(() => {
+      // Cleanup registered user
+      cy.request({ url: '/api/users', headers: authHeaders }).then(res => {
+        const user = res.body.find(u =>
+          u.username.toLowerCase() === CASE_USER.toLowerCase()
+        )
+        if (user) {
+          cy.request({
+            method: 'DELETE',
+            url: `/api/users/${user.id || user._id}`,
+            headers: authHeaders,
+            failOnStatusCode: false,
+          })
+        }
+      })
+    })
+
+    it('registers a user with mixed case', () => {
+      cy.request({
+        method: 'POST',
+        url: '/api/register',
+        body: { username: CASE_USER, password: CASE_PASS },
+        failOnStatusCode: false,
+      }).then(res => {
+        expect(res.status).to.eq(201)
+        expect(res.body.token).to.be.a('string')
+      })
+    })
+
+    it('rejects registration with same username in different case', () => {
+      cy.request({
+        method: 'POST',
+        url: '/api/register',
+        body: { username: CASE_USER.toLowerCase(), password: CASE_PASS },
+        failOnStatusCode: false,
+      }).then(res => {
+        expect(res.status).to.eq(400)
+      })
+    })
+
+    it('rejects registration with all-uppercase variant', () => {
+      cy.request({
+        method: 'POST',
+        url: '/api/register',
+        body: { username: CASE_USER.toUpperCase(), password: CASE_PASS },
+        failOnStatusCode: false,
+      }).then(res => {
+        expect(res.status).to.eq(400)
+      })
+    })
+
+    it('allows case-insensitive login', () => {
+      cy.request({
+        method: 'POST',
+        url: '/api/login',
+        body: { username: CASE_USER.toLowerCase(), password: CASE_PASS },
+        failOnStatusCode: false,
+      }).then(res => {
+        expect(res.status).to.eq(200)
+        expect(res.body.token).to.be.a('string')
+      })
+    })
+  })
+
+  // -------------------------------------------------------------------------
+  // API: One-time username change via PUT /api/me/username
+  // -------------------------------------------------------------------------
+  describe('API: one-time username change', () => {
+    const RENAME_USER = 'cypress_rename_test'
+    const RENAME_PASS = 'rename1234'
+    let renameToken
+    let renameUserId
+
+    before(() => {
+      // Cleanup leftovers
+      cy.request({ url: '/api/users', headers: authHeaders }).then(res => {
+        for (const name of [RENAME_USER, 'cypress_renamed']) {
+          const leftover = res.body.find(u => u.username.toLowerCase() === name)
+          if (leftover) {
+            cy.request({
+              method: 'DELETE',
+              url: `/api/users/${leftover.id || leftover._id}`,
+              headers: authHeaders,
+              failOnStatusCode: false,
+            })
+          }
+        }
+      })
+    })
+
+    after(() => {
+      // Cleanup
+      if (renameUserId) {
+        cy.request({
+          method: 'DELETE',
+          url: `/api/users/${renameUserId}`,
+          headers: authHeaders,
+          failOnStatusCode: false,
+        })
+      }
+    })
+
+    it('registers a user for rename test', () => {
+      cy.request({
+        method: 'POST',
+        url: '/api/register',
+        body: { username: RENAME_USER, password: RENAME_PASS },
+      }).then(res => {
+        expect(res.status).to.eq(201)
+        renameToken = res.body.token
+
+        // Get user ID
+        cy.request({ url: '/api/users', headers: authHeaders }).then(listRes => {
+          const u = listRes.body.find(x => x.username === RENAME_USER)
+          renameUserId = u.id || u._id
+        })
+      })
+    })
+
+    it('GET /api/me returns username_changed=false initially', () => {
+      cy.request({
+        url: '/api/me',
+        headers: { Authorization: `Bearer ${renameToken}` },
+      }).then(res => {
+        expect(res.status).to.eq(200)
+        expect(res.body.username_changed).to.eq(false)
+      })
+    })
+
+    it('renames username successfully the first time', () => {
+      cy.request({
+        method: 'PUT',
+        url: '/api/me/username',
+        headers: { Authorization: `Bearer ${renameToken}` },
+        body: { username: 'cypress_renamed' },
+      }).then(res => {
+        expect(res.status).to.eq(200)
+        expect(res.body.ok).to.eq(true)
+        expect(res.body.username).to.eq('cypress_renamed')
+      })
+    })
+
+    it('GET /api/me returns username_changed=true after rename', () => {
+      cy.request({
+        url: '/api/me',
+        headers: { Authorization: `Bearer ${renameToken}` },
+      }).then(res => {
+        expect(res.body.username_changed).to.eq(true)
+      })
+    })
+
+    it('rejects second rename attempt', () => {
+      cy.request({
+        method: 'PUT',
+        url: '/api/me/username',
+        headers: { Authorization: `Bearer ${renameToken}` },
+        body: { username: 'cypress_another_name' },
+        failOnStatusCode: false,
+      }).then(res => {
+        expect(res.status).to.eq(400)
+      })
+    })
+  })
+
+  // -------------------------------------------------------------------------
+  // API: en_name auto-translation on recipe create (no explicit en_name)
+  // -------------------------------------------------------------------------
+  describe('API: en_name auto-translation on create', () => {
+    let recipeId
+
+    after(() => {
+      if (recipeId) {
+        cy.request({
+          method: 'DELETE',
+          url: `/api/recipes/${recipeId}`,
+          headers: authHeaders,
+          failOnStatusCode: false,
+        })
+      }
+    })
+
+    it('auto-translates en_name when creating recipe without en_name', () => {
+      cy.request({
+        method: 'POST',
+        url: '/api/recipes',
+        headers: authHeaders,
+        body: {
+          name: '排毒按摩',
+          ingredients: [{ oil_name: '薰衣草', drops: 3 }],
+          tags: [],
+        },
+      }).then(res => {
+        expect(res.status).to.be.oneOf([200, 201])
+        recipeId = res.body.id
+
+        cy.request('/api/recipes').then(listRes => {
+          const found = listRes.body.find(r => r.id === recipeId)
+          expect(found).to.exist
+          expect(found.en_name).to.be.a('string')
+          expect(found.en_name.length).to.be.greaterThan(0)
+          // auto_translate('排毒按摩') should produce 'Detox Massage'
+          expect(found.en_name).to.include('Detox')
+          expect(found.en_name).to.include('Massage')
+        })
+      })
+    })
+  })
+
+  // -------------------------------------------------------------------------
+  // API: Recipe name change auto-retranslates en_name
+  // -------------------------------------------------------------------------
+  describe('API: rename recipe auto-retranslates en_name', () => {
+    let recipeId
+
+    after(() => {
+      if (recipeId) {
+        cy.request({
+          method: 'DELETE',
+          url: `/api/recipes/${recipeId}`,
+          headers: authHeaders,
+          failOnStatusCode: false,
+        })
+      }
+    })
+
+    it('creates recipe with auto en_name, then renames to verify retranslation', () => {
+      cy.request({
+        method: 'POST',
+        url: '/api/recipes',
+        headers: authHeaders,
+        body: {
+          name: '助眠喷雾',
+          ingredients: [{ oil_name: '薰衣草', drops: 5 }],
+          tags: [],
+        },
+      }).then(res => {
+        recipeId = res.body.id
+
+        // Verify initial auto-translation
+        cy.request('/api/recipes').then(listRes => {
+          const r = listRes.body.find(x => x.id === recipeId)
+          expect(r.en_name).to.include('Sleep')
+
+          // Rename to completely different name
+          cy.request({
+            method: 'PUT',
+            url: `/api/recipes/${recipeId}`,
+            headers: authHeaders,
+            body: { name: '肩颈按摩' },
+          }).then(() => {
+            cy.request('/api/recipes').then(list2 => {
+              const r2 = list2.body.find(x => x.id === recipeId)
+              // Should now be retranslated to Neck & Shoulder Massage
+              expect(r2.en_name).to.include('Neck')
+              expect(r2.en_name).to.include('Massage')
+              // Should NOT contain Sleep anymore
+              expect(r2.en_name).to.not.include('Sleep')
+            })
+          })
+        })
+      })
+    })
+
+    it('does not retranslate when explicit en_name provided on update', () => {
+      cy.request({
+        method: 'PUT',
+        url: `/api/recipes/${recipeId}`,
+        headers: authHeaders,
+        body: { name: '免疫配方', en_name: 'my custom name' },
+      }).then(() => {
+        cy.request('/api/recipes').then(listRes => {
+          const r = listRes.body.find(x => x.id === recipeId)
+          expect(r.en_name).to.eq('My Custom Name') // title-cased
+        })
+      })
+    })
+  })
+
+  // -------------------------------------------------------------------------
+  // API: Delete user transfers diary to admin (with username appended)
+  // -------------------------------------------------------------------------
+  describe('API: delete user diary transfer with username', () => {
+    const XFER_USER = 'cypress_xfer_test'
+    const XFER_PASS = 'xfer1234'
+    let xferUserId
+    let xferToken
+
+    before(() => {
+      // Cleanup leftovers
+      cy.request({ url: '/api/users', headers: authHeaders }).then(res => {
+        const leftover = res.body.find(u => u.username === XFER_USER)
+        if (leftover) {
+          cy.request({
+            method: 'DELETE',
+            url: `/api/users/${leftover.id || leftover._id}`,
+            headers: authHeaders,
+            failOnStatusCode: false,
+          })
+        }
+      })
+    })
+
+    it('registers user, adds diary, deletes user, verifies transfer', () => {
+      // Register
+      cy.request({
+        method: 'POST',
+        url: '/api/register',
+        body: { username: XFER_USER, password: XFER_PASS },
+      }).then(regRes => {
+        xferToken = regRes.body.token
+
+        // Get user id
+        cy.request({ url: '/api/users', headers: authHeaders }).then(listRes => {
+          const u = listRes.body.find(x => x.username === XFER_USER)
+          xferUserId = u.id || u._id
+
+          const userAuth = { Authorization: `Bearer ${xferToken}` }
+
+          // Add unique diary entry
+          cy.request({
+            method: 'POST',
+            url: '/api/diary',
+            headers: userAuth,
+            body: {
+              name: 'PR28转移日记',
+              ingredients: [
+                { oil: '檀香', drops: 7 },
+                { oil: '岩兰草', drops: 3 },
+              ],
+              note: '转移测试PR28',
+            },
+          }).then(() => {
+            // Delete user
+            cy.request({
+              method: 'DELETE',
+              url: `/api/users/${xferUserId}`,
+              headers: authHeaders,
+            }).then(delRes => {
+              expect(delRes.body.ok).to.eq(true)
+
+              // Verify diary was transferred to admin with username appended
+              cy.request({
+                url: '/api/diary',
+                headers: authHeaders,
+              }).then(diaryRes => {
+                const transferred = diaryRes.body.find(
+                  d => d.name && d.name.includes('PR28转移日记') && d.name.includes(XFER_USER)
+                )
+                expect(transferred).to.exist
+                expect(transferred.note).to.eq('转移测试PR28')
+
+                // Cleanup
+                if (transferred) {
+                  cy.request({
+                    method: 'DELETE',
+                    url: `/api/diary/${transferred.id}`,
+                    headers: authHeaders,
+                    failOnStatusCode: false,
+                  })
+                }
+              })
+            })
+          })
+        })
+      })
+    })
+  })
 })

frontend/src/App.vue

@@ -15,7 +15,7 @@
       <div class="header-right" @click="toggleUserMenu">
         <template v-if="auth.isLoggedIn">
           <span v-if="auth.isBusiness" class="biz-badge" title="商业认证用户">🏢</span>
-          <span class="user-name">{{ auth.user.display_name || auth.user.username }} ▾</span>
+          <span class="user-name">{{ auth.user.username }} ▾</span>
           <span v-if="unreadNotifCount > 0" class="notif-badge">{{ unreadNotifCount }}</span>
         </template>
         <template v-else>

frontend/src/__tests__/pr27Features.test.js

@@ -1,5 +1,5 @@
 import { describe, it, expect } from 'vitest'
-import { recipeNameEn } from '../composables/useOilTranslation'
+import { recipeNameEn, oilEn } from '../composables/useOilTranslation'
 
 // ---------------------------------------------------------------------------
 // EDITOR_ONLY_TAGS includes '已下架'
@@ -169,4 +169,117 @@ describe('duplicate oil prevention', () => {
     const isDup = ings.some(i => i !== ing && i.oil === '薰衣草')
     expect(isDup).toBe(false)
   })
+
+  it('handles empty ingredient list (no duplicates)', () => {
+    const ings = []
+    const isDup = ings.some(i => i.oil === '薰衣草')
+    expect(isDup).toBe(false)
+  })
+})
+
+// ---------------------------------------------------------------------------
+// recipeNameEn — additional edge cases for PR28
+// ---------------------------------------------------------------------------
+describe('recipeNameEn — PR28 additional cases', () => {
+  it('translates 排毒配方 → Detox Blend', () => {
+    expect(recipeNameEn('排毒配方')).toBe('Detox Blend')
+  })
+
+  it('translates 呼吸系统护理 → Respiratory System Care', () => {
+    expect(recipeNameEn('呼吸系统护理')).toBe('Respiratory System Care')
+  })
+
+  it('translates 儿童助眠 → Children\'s Sleep Aid', () => {
+    expect(recipeNameEn('儿童助眠')).toBe("Children's Sleep Aid")
+  })
+
+  it('translates 美容按摩 → Beauty Massage', () => {
+    expect(recipeNameEn('美容按摩')).toBe('Beauty Massage')
+  })
+
+  it('handles mixed Chinese and ASCII text', () => {
+    // Unknown Chinese chars are skipped; if ASCII appears, it's kept
+    const result = recipeNameEn('testBlend')
+    // No Chinese keyword matches, falls back to original
+    expect(result).toBe('testBlend')
+  })
+
+  it('handles single-keyword name', () => {
+    expect(recipeNameEn('免疫')).toBe('Immunity')
+  })
+
+  it('translates compound: 肩颈按摩配方 → Neck & Shoulder Massage Blend', () => {
+    expect(recipeNameEn('肩颈按摩配方')).toBe('Neck & Shoulder Massage Blend')
+  })
+})
+
+// ---------------------------------------------------------------------------
+// oilEn — English oil name translation
+// ---------------------------------------------------------------------------
+describe('oilEn', () => {
+  it('translates known oils', () => {
+    expect(oilEn('薰衣草')).toBe('Lavender')
+    expect(oilEn('茶树')).toBe('Tea Tree')
+    expect(oilEn('乳香')).toBe('Frankincense')
+  })
+
+  it('handles 复方 suffix removal', () => {
+    expect(oilEn('舒缓复方')).toBe('Past Tense')
+  })
+
+  it('handles 复方 suffix addition', () => {
+    // '呼吸' maps via '呼吸复方' → 'Breathe'
+    expect(oilEn('呼吸')).toBe('Breathe')
+  })
+
+  it('returns empty string for unknown oil', () => {
+    expect(oilEn('不存在的油')).toBe('')
+  })
+})
+
+// ---------------------------------------------------------------------------
+// Case-insensitive username logic (pure function)
+// ---------------------------------------------------------------------------
+describe('case-insensitive username matching', () => {
+  const matchCaseInsensitive = (input, existing) =>
+    existing.some(u => u.toLowerCase() === input.toLowerCase())
+
+  it('detects duplicate usernames case-insensitively', () => {
+    const existing = ['TestUser', 'Alice', 'Bob']
+    expect(matchCaseInsensitive('testuser', existing)).toBe(true)
+    expect(matchCaseInsensitive('TESTUSER', existing)).toBe(true)
+    expect(matchCaseInsensitive('TestUser', existing)).toBe(true)
+  })
+
+  it('allows unique username', () => {
+    const existing = ['TestUser', 'Alice']
+    expect(matchCaseInsensitive('Charlie', existing)).toBe(false)
+  })
+
+  it('is case-insensitive for mixed-case inputs', () => {
+    const existing = ['alice']
+    expect(matchCaseInsensitive('Alice', existing)).toBe(true)
+    expect(matchCaseInsensitive('ALICE', existing)).toBe(true)
+    expect(matchCaseInsensitive('aLiCe', existing)).toBe(true)
+  })
+})
+
+// ---------------------------------------------------------------------------
+// One-time username change logic
+// ---------------------------------------------------------------------------
+describe('one-time username change guard', () => {
+  it('blocks rename when username_changed is truthy', () => {
+    const user = { username_changed: 1 }
+    expect(!!user.username_changed).toBe(true)
+  })
+
+  it('allows rename when username_changed is falsy', () => {
+    const user = { username_changed: 0 }
+    expect(!!user.username_changed).toBe(false)
+  })
+
+  it('allows rename when username_changed is undefined', () => {
+    const user = {}
+    expect(!!user.username_changed).toBe(false)
+  })
 })

frontend/src/components/LoginModal.vue

@@ -37,14 +37,6 @@
           class="login-input"
           @keydown.enter="submit"
         />
-        <input
-          v-if="mode === 'register'"
-          v-model="displayName"
-          type="text"
-          placeholder="显示名称（可选）"
-          class="login-input"
-          @keydown.enter="submit"
-        />
 
         <div v-if="errorMsg" class="login-error">{{ errorMsg }}</div>
 
@@ -80,7 +72,6 @@ const mode = ref('login')
 const username = ref('')
 const password = ref('')
 const confirmPassword = ref('')
-const displayName = ref('')
 const errorMsg = ref('')
 const loading = ref(false)
 const showFeedback = ref(false)
@@ -109,11 +100,7 @@ async function submit() {
       await auth.login(username.value.trim(), password.value)
       ui.showToast('登录成功')
     } else {
-      await auth.register(
-        username.value.trim(),
-        password.value,
-        displayName.value.trim() || username.value.trim()
-      )
+      await auth.register(username.value.trim(), password.value)
       ui.showToast('注册成功')
     }
     emit('close')

frontend/src/components/UserMenu.vue

@@ -1,7 +1,10 @@
 <template>
   <div class="usermenu-overlay" @mousedown.self="$emit('close')">
     <div class="usermenu-card">
-      <div class="usermenu-name">{{ auth.user.display_name || auth.user.username }}</div>
+      <div class="usermenu-name">
+        {{ auth.user.username }}
+        <button v-if="!auth.user.username_changed" class="rename-btn" @click="changeUsername">✏️ 改名</button>
+      </div>
 
       <div class="usermenu-actions">
         <button class="usermenu-btn" @click="goMyDiary">
@@ -38,6 +41,9 @@
               <div v-if="!n.is_read" class="notif-actions">
                 <!-- 搜索未收录通知：已添加按钮 -->
                 <button v-if="isSearchMissing(n)" class="notif-action-btn notif-btn-added" @click="markAdded(n)">已添加</button>
+                <!-- 用户名更新通知：去修改按钮（已改过则显示已读） -->
+                <button v-else-if="isUsernameNotice(n) && !auth.user.username_changed" class="notif-action-btn notif-btn-plan" @click="goRename(n)">去修改</button>
+                <button v-else-if="isUsernameNotice(n) && auth.user.username_changed" class="notif-mark-one" @click="markOneRead(n)">已读</button>
                 <!-- 审核类通知：去审核按钮 -->
                 <button v-else-if="isReviewable(n)" class="notif-action-btn notif-btn-review" @click="goReview(n)">去审核</button>
                 <!-- 默认：已读按钮 -->
@@ -129,6 +135,36 @@ function isSearchMissing(n) {
   return n.title && n.title.includes('用户需求')
 }
 
+async function changeUsername() {
+  const { showPrompt } = await import('../composables/useDialog')
+  const newName = await showPrompt('输入新用户名（只能修改一次）：', auth.user.username)
+  if (!newName || !newName.trim() || newName.trim() === auth.user.username) return
+  try {
+    const res = await api('/api/me/username', {
+      method: 'PUT',
+      body: JSON.stringify({ username: newName.trim() }),
+    })
+    if (res.ok) {
+      await auth.loadMe()
+      ui.showToast('用户名已修改')
+    } else {
+      const err = await res.json().catch(() => ({}))
+      ui.showToast(err.detail || '修改失败')
+    }
+  } catch {
+    ui.showToast('修改失败')
+  }
+}
+
+function isUsernameNotice(n) {
+  return n.title && n.title.includes('用户名更新')
+}
+
+function goRename(n) {
+  markOneRead(n)
+  changeUsername()
+}
+
 function isReviewable(n) {
   if (!n.title) return false
   // Admin: review recipe/business/applications
@@ -215,7 +251,9 @@ onMounted(loadNotifications)
   z-index: 4001;
 }
 
-.usermenu-name { font-size: 16px; font-weight: 600; color: #3e3a44; margin-bottom: 14px; }
+.usermenu-name { font-size: 16px; font-weight: 600; color: #3e3a44; margin-bottom: 14px; display: flex; align-items: center; gap: 8px; }
+.rename-btn { background: none; border: none; font-size: 12px; color: #b0aab5; cursor: pointer; padding: 0; }
+.rename-btn:hover { color: #4a9d7e; }
 
 .usermenu-actions { display: flex; flex-direction: column; gap: 4px; }
 .usermenu-btn {

frontend/src/stores/auth.js

@@ -40,9 +40,10 @@ export const useAuthStore = defineStore('auth', () => {
         id: data.id,
         role: data.role,
         username: data.username,
-        display_name: data.display_name,
+        display_name: data.username,
         has_password: data.has_password ?? false,
         business_verified: data.business_verified ?? false,
+        username_changed: data.username_changed ?? false,
       }
     } catch {
       logout()
@@ -56,11 +57,10 @@ export const useAuthStore = defineStore('auth', () => {
     await loadMe()
   }
 
-  async function register(username, password, displayName) {
+  async function register(username, password) {
     const data = await api.post('/api/register', {
       username,
       password,
-      display_name: displayName,
     })
     token.value = data.token
     localStorage.setItem('oil_auth_token', data.token)

frontend/src/views/Inventory.vue

@@ -1,5 +1,11 @@
 <template>
   <div class="inventory-page">
+    <!-- Login prompt -->
+    <div v-if="!auth.isLoggedIn" class="login-prompt">
+      <p>登录后可管理个人库存</p>
+      <button class="btn-primary" @click="ui.openLogin()">登录 / 注册</button>
+    </div>
+    <template v-else>
     <!-- Search + direct add -->
     <div class="search-box">
       <input
@@ -84,6 +90,7 @@
     <div v-else class="empty-hint">
       {{ ownedOils.length ? '暂无完全匹配的配方' : '添加精油后自动推荐配方' }}
     </div>
+    </template>
   </div>
 </template>
 
@@ -473,4 +480,7 @@ onMounted(() => {
   font-size: 13px;
   padding: 24px 0;
 }
+
+.login-prompt { text-align: center; padding: 60px 20px; color: #6b6375; }
+.login-prompt p { margin-bottom: 16px; font-size: 15px; }
 </style>

frontend/src/views/MyDiary.vue

@@ -208,22 +208,6 @@
 
     <!-- Account Tab -->
     <div v-if="activeTab === 'account'" class="tab-content">
-      <div class="section-card">
-        <h4>👤 账号设置</h4>
-
-        <div class="form-group">
-          <label>显示名称</label>
-          <input v-model="displayName" class="form-input" />
-          <button class="btn-primary btn-sm" style="margin-top:6px" @click="updateDisplayName">保存</button>
-        </div>
-
-        <div class="form-group">
-          <label>用户名</label>
-          <div class="form-static">{{ auth.user.username }}</div>
-        </div>
-
-      </div>
-
       <div class="section-card">
         <h4>🔑 修改密码</h4>
         <div class="form-group">

frontend/src/views/UserManagement.vue

@@ -82,10 +82,7 @@
     <div class="user-list">
       <div v-for="u in filteredUsers" :key="u._id || u.id" class="user-card">
         <div class="user-info">
-          <div class="user-name">
-            {{ u.display_name || u.username }}
-            <span class="user-username" v-if="u.display_name">@{{ u.username }}</span>
-          </div>
+          <div class="user-name">{{ u.username }}</div>
           <div class="user-meta">
             <span class="user-role-badge" :class="'role-' + u.role">{{ roleLabel(u.role) }}</span>
             <span v-if="u.business_verified" class="biz-badge">💼 商业认证</span>
@@ -757,4 +754,5 @@ onMounted(() => {
     justify-content: flex-end;
   }
 }
+
 </style>