feat(postcard): profile country, country_from, per-user card number uniqueness, public page overhaul - Profile: add country field for default origin country - Postcard: add country_from field, auto-fill from profile.country on create - card_number uniqueness: change from global to per-user (profile_id + card_number) - Public pages: remove card_number display, only show cards with image_front - Public pages: show country as from→to format - Index page: no time display, add register button, fix lightbox with prev/next - Infinite scroll: add /api/public/cards endpoints and IntersectionObserver - Internal pages: update postcards list/detail for country_from display - i18n: add profiles.country_ph, pc_form.country_from, pc_detail.route

app/locales/en.json

@@ -6,6 +6,7 @@
   "index.title": "Mailova",
   "index.subtitle": "Postcards from around the world",
   "index.go_login": "Login",
+  "index.go_register": "Register",
   "index.empty": "No public postcards yet",
   "nav.profiles": "Profiles",
   "nav.settings": "Settings",
@@ -64,6 +65,7 @@
   "profiles.total": "Total",
   "profiles.countries": "Countries",
   "profiles.notes_ph": "Notes (private)",
+  "profiles.country_ph": "Country",
   "profiles.save": "Save",
   "profiles.created_at": "Created",
   "profiles.view": "View",
@@ -96,6 +98,7 @@
   "pc_detail.status": "Status",
   "pc_detail.recipient": "Recipient",
   "pc_detail.country": "Country",
+  "pc_detail.route": "Route",
   "pc_detail.send_time": "Sent date",
   "pc_detail.arrival_time": "Arrival date",
   "pc_detail.sender": "Sender",
@@ -112,6 +115,7 @@
   "pc_form.status": "Status",
   "pc_form.recipient": "Recipient",
   "pc_form.country": "Country",
+  "pc_form.country_from": "From",
   "pc_form.send_time": "Sent date",
   "pc_form.arrival_time": "Arrival date",
   "pc_form.sender": "Sender",

app/locales/zh.json

@@ -6,6 +6,7 @@
   "index.title": "星笺",
   "index.subtitle": "来自世界各地的明信片",
   "index.go_login": "登录",
+  "index.go_register": "注册",
   "index.empty": "暂无公开明信片",
   "nav.profiles": "Profile",
   "nav.settings": "设置",
@@ -64,6 +65,7 @@
   "profiles.total": "总计",
   "profiles.countries": "国家",
   "profiles.notes_ph": "备注（仅自己可见）",
+  "profiles.country_ph": "国家",
   "profiles.save": "保存",
   "profiles.created_at": "创建于",
   "profiles.view": "查看",
@@ -96,6 +98,7 @@
   "pc_detail.status": "状态",
   "pc_detail.recipient": "收件人",
   "pc_detail.country": "国家/地区",
+  "pc_detail.route": "路线",
   "pc_detail.send_time": "寄出时间",
   "pc_detail.arrival_time": "到达时间",
   "pc_detail.sender": "发件人",
@@ -112,6 +115,7 @@
   "pc_form.status": "状态",
   "pc_form.recipient": "收件人",
   "pc_form.country": "国家/地区",
+  "pc_form.country_from": "寄出地",
   "pc_form.send_time": "寄出时间",
   "pc_form.arrival_time": "到达时间",
   "pc_form.sender": "发件人",

app/models.py

@@ -1,6 +1,6 @@
 from datetime import datetime, timezone
 
-from sqlalchemy import Boolean, Column, DateTime, ForeignKey, Integer, String, Text
+from sqlalchemy import Boolean, Column, DateTime, ForeignKey, Integer, String, Text, UniqueConstraint
 from sqlalchemy.orm import relationship, validates
 
 from app.database import Base
@@ -61,6 +61,7 @@ class Profile(Base):
     id = Column(Integer, primary_key=True, index=True)
     user_id = Column(Integer, ForeignKey("users.id", ondelete="CASCADE"), nullable=False)
     nickname = Column(String(64), nullable=False)
+    country = Column(String(2), nullable=True)
     showcase_enabled = Column(default=False, nullable=False)
     showcase_visible = Column(String(16), nullable=False, default="both")
     notes = Column(Text, nullable=False, default="")
@@ -72,14 +73,18 @@ class Profile(Base):
 
 class Postcard(Base):
     __tablename__ = "postcards"
+    __table_args__ = (
+        UniqueConstraint("profile_id", "card_number", name="uq_postcards_profile_card_number"),
+    )
 
     id = Column(Integer, primary_key=True, index=True)
     profile_id = Column(Integer, ForeignKey("profiles.id", ondelete="CASCADE"), nullable=False)
-    card_number = Column(String(64), nullable=False, unique=True)
+    card_number = Column(String(64), nullable=False)
     status = Column(String(16), nullable=False)
     # sent & delivered
     recipient_name = Column(String(64))
     country = Column(String(64))
+    country_from = Column(String(2))
     send_time = Column(DateTime)
     arrival_time = Column(DateTime)
     # received
@@ -100,6 +105,10 @@ class Postcard(Base):
     def _upper_country(self, key, value):
         return value.strip().upper() if value else None
 
+    @validates("country_from")
+    def _upper_country_from(self, key, value):
+        return value.strip().upper() if value else None
+
 
 class ApiKey(Base):
     __tablename__ = "api_keys"

app/routers/api.py

@@ -81,13 +81,16 @@ def get_api_user_optional(
 
 class ProfileCreate(BaseModel):
     nickname: str
+    country: str | None = None
 
 class ProfileUpdate(BaseModel):
     nickname: str | None = None
+    country: str | None = None
 
 class ProfileOut(BaseModel):
     id: int
     nickname: str
+    country: str | None
     showcase_enabled: bool
     showcase_visible: str
     notes: str
@@ -101,6 +104,7 @@ class PostcardCreate(BaseModel):
     status: str
     recipient_name: str | None = None
     country: str | None = None
+    country_from: str | None = None
     send_time: str | None = None
     arrival_time: str | None = None
     sender_name: str | None = None
@@ -112,6 +116,7 @@ class PostcardUpdate(BaseModel):
     status: str | None = None
     recipient_name: str | None = None
     country: str | None = None
+    country_from: str | None = None
     send_time: str | None = None
     arrival_time: str | None = None
     sender_name: str | None = None
@@ -125,6 +130,7 @@ class PostcardOut(BaseModel):
     status: str
     recipient_name: str | None
     country: str | None
+    country_from: str | None
     send_time: datetime | None
     arrival_time: datetime | None
     sender_name: str | None
@@ -205,7 +211,8 @@ def create_profile(
     db: DbSession = Depends(get_db),
     ak: ApiKey = Depends(require_scopes(PERM_PROFILES_WRITE)),
 ):
-    p = Profile(nickname=body.nickname.strip(), user_id=ak.user_id)
+    c = body.country.strip().upper() if body.country else None
+    p = Profile(nickname=body.nickname.strip(), user_id=ak.user_id, country=c)
     db.add(p)
     db.commit()
     db.refresh(p)
@@ -231,6 +238,8 @@ def update_profile(
     p = _profile_or_404(ak.user, profile_id, db)
     if body.nickname is not None:
         p.nickname = body.nickname.strip()
+    if body.country is not None:
+        p.country = body.country.strip().upper() if body.country else None
     db.commit()
     db.refresh(p)
     return p
@@ -275,7 +284,10 @@ def create_postcard(
 ):
     _profile_or_404(ak.user, profile_id, db)
     cn = body.card_number.strip()
-    if db.query(Postcard).filter(Postcard.card_number == cn).first():
+    dup = db.query(Postcard).join(Profile).filter(
+        Postcard.card_number == cn, Profile.user_id == ak.user.id
+    ).first()
+    if dup:
         raise HTTPException(status_code=409, detail="Card number already exists")
     pc = Postcard(
         profile_id=profile_id,
@@ -283,6 +295,7 @@ def create_postcard(
         status=body.status,
         recipient_name=body.recipient_name,
         country=body.country.strip().upper() if body.country else None,
+        country_from=body.country_from.strip().upper() if body.country_from else None,
         send_time=_parse_date(body.send_time),
         arrival_time=_parse_date(body.arrival_time),
         sender_name=body.sender_name,
@@ -320,12 +333,17 @@ def update_postcard(
             setattr(pc, field, val.strip() if isinstance(val, str) else val)
     if body.card_number is not None:
         cn = body.card_number.strip()
-        dup = db.query(Postcard).filter(Postcard.card_number == cn, Postcard.id != postcard_id).first()
+        dup = db.query(Postcard).join(Profile).filter(
+            Postcard.card_number == cn, Postcard.id != postcard_id,
+            Profile.user_id == ak.user.id
+        ).first()
         if dup:
             raise HTTPException(status_code=409, detail="Card number already exists")
         pc.card_number = cn
     if body.country is not None:
         pc.country = body.country.strip().upper() if body.country else None
+    if body.country_from is not None:
+        pc.country_from = body.country_from.strip().upper() if body.country_from else None
     for field in ("send_time", "arrival_time", "receive_time"):
         val = getattr(body, field)
         if val is not None:

app/routers/web.py

@@ -4,7 +4,7 @@ from random import shuffle
 from uuid import uuid4
 
 from fastapi import APIRouter, Depends, File, Form, Query, Request, UploadFile
-from fastapi.responses import HTMLResponse, RedirectResponse
+from fastapi.responses import HTMLResponse, JSONResponse, RedirectResponse
 from fastapi.templating import Jinja2Templates
 from sqlalchemy.orm import Session
 
@@ -126,7 +126,8 @@ def index_page(request: Request, db: Session = Depends(get_db)):
         ).all()
         for p in profiles:
             cards = db.query(Postcard).filter(
-                Postcard.profile_id == p.id, Postcard.showcase_hidden == False
+                Postcard.profile_id == p.id, Postcard.showcase_hidden == False,
+                Postcard.image_front.isnot(None), Postcard.image_front != ""
             ).all()
             for c in cards:
                 visible = True
@@ -147,7 +148,92 @@ def index_page(request: Request, db: Session = Depends(get_db)):
         lang = "zh"
 
     return templates.TemplateResponse("index.html", {
-        "request": request, "postcards": all_postcards, "lang": lang,
+        "request": request, "postcards": all_postcards[:20], "lang": lang,
+        "has_more": len(all_postcards) > 20,
+    })
+
+
+@router.get("/api/public/cards")
+def api_public_cards(
+    request: Request,
+    page: int = Query(1, ge=1),
+    limit: int = Query(20, ge=1, le=100),
+    db: Session = Depends(get_db),
+):
+    all_cards: list[Postcard] = []
+    users = db.query(User).filter(User.showcase_mode.isnot(None)).all()
+    for u in users:
+        profiles = db.query(Profile).filter(
+            Profile.user_id == u.id, Profile.showcase_enabled == True
+        ).all()
+        for p in profiles:
+            cards = db.query(Postcard).filter(
+                Postcard.profile_id == p.id, Postcard.showcase_hidden == False,
+                Postcard.image_front.isnot(None), Postcard.image_front != ""
+            ).all()
+            for c in cards:
+                vis = True
+                if c.status in ("sent", "delivered") and p.showcase_visible not in ("sent", "both"):
+                    vis = False
+                if c.status == "received" and p.showcase_visible not in ("received", "both"):
+                    vis = False
+                if vis:
+                    all_cards.append(c)
+    shuffle(all_cards)
+    total = len(all_cards)
+    start = (page - 1) * limit
+    batch = all_cards[start:start + limit]
+    return JSONResponse({
+        "total": total,
+        "page": page,
+        "has_more": start + limit < total,
+        "cards": [{
+            "image_front": c.image_front,
+            "country_from": c.country_from,
+            "country": c.country,
+            "status": c.status,
+        } for c in batch],
+    })
+
+
+@router.get("/api/public/cards/{username}")
+def api_public_cards_user(
+    username: str,
+    request: Request,
+    page: int = Query(1, ge=1),
+    limit: int = Query(20, ge=1, le=100),
+    tab: str = Query("sent"),
+    db: Session = Depends(get_db),
+):
+    user = db.query(User).filter(User.username == username).first()
+    if not user:
+        return JSONResponse({"error": "not found"}, status_code=404)
+    profiles = db.query(Profile).filter(
+        Profile.user_id == user.id, Profile.showcase_enabled == True
+    ).all()
+    all_cards: list[Postcard] = []
+    for p in profiles:
+        cards = db.query(Postcard).filter(
+            Postcard.profile_id == p.id, Postcard.showcase_hidden == False,
+            Postcard.image_front.isnot(None), Postcard.image_front != ""
+        ).all()
+        if tab == "sent" and p.showcase_visible in ("sent", "both"):
+            all_cards.extend([c for c in cards if c.status in ("sent", "delivered")])
+        elif tab == "received" and p.showcase_visible in ("received", "both"):
+            all_cards.extend([c for c in cards if c.status == "received"])
+    all_cards.sort(key=lambda c: c.send_time or c.created_at, reverse=True)
+    total = len(all_cards)
+    start = (page - 1) * limit
+    batch = all_cards[start:start + limit]
+    return JSONResponse({
+        "total": total,
+        "page": page,
+        "has_more": start + limit < total,
+        "cards": [{
+            "image_front": c.image_front,
+            "country_from": c.country_from,
+            "country": c.country,
+        } for c in batch],
     })
 
 
@@ -565,8 +651,9 @@ def profile_list(request: Request, user: User = Depends(get_current_user_web), d
 
 
 @router.post("/profiles")
-def profile_create(request: Request, nickname: str = Form(...), user: User = Depends(get_current_user_web), db: Session = Depends(get_db)):
+def profile_create(request: Request, nickname: str = Form(...), country: str = Form(""), user: User = Depends(get_current_user_web), db: Session = Depends(get_db)):
-    db.add(Profile(user_id=user.id, nickname=nickname))
+    c = country.strip().upper() if country else None
+    db.add(Profile(user_id=user.id, nickname=nickname, country=c))
     db.commit()
     return _redirect("/profiles")
 
@@ -581,10 +668,11 @@ def profile_delete(profile_id: int, user: User = Depends(get_current_user_web),
 
 
 @router.post("/profiles/{profile_id}/rename")
-def profile_rename(profile_id: int, nickname: str = Form(...), user: User = Depends(get_current_user_web), db: Session = Depends(get_db)):
+def profile_rename(profile_id: int, nickname: str = Form(...), country: str = Form(""), user: User = Depends(get_current_user_web), db: Session = Depends(get_db)):
     p = db.query(Profile).filter(Profile.id == profile_id, Profile.user_id == user.id).first()
     if p:
         p.nickname = nickname
+        p.country = country.strip().upper() if country else None
         db.commit()
     return _redirect("/profiles")
 
@@ -649,6 +737,7 @@ def postcard_create(
     status: str = Form(...),
     recipient_name: str = Form(""),
     country: str = Form(""),
+    country_from: str = Form(""),
     send_time: str = Form(""),
     arrival_time: str = Form(""),
     sender_name: str = Form(""),
@@ -662,7 +751,10 @@ def postcard_create(
         return _redirect("/profiles")
 
     cn = card_number.strip()
-    if db.query(Postcard).filter(Postcard.card_number == cn).first():
+    dup = db.query(Postcard).join(Profile).filter(
+        Postcard.card_number == cn, Profile.user_id == user.id
+    ).first()
+    if dup:
         return templates.TemplateResponse("postcard_form.html", {
             "request": request, "user": user, "profile": profile, "postcard": None,
             "error": _t("pc_list.duplicate", user.language),
@@ -686,6 +778,7 @@ def postcard_create(
         status=status,
         recipient_name=recipient_name or None,
         country=(country.strip().upper() if country else None),
+        country_from=(country_from.strip().upper() if country_from else profile.country),
         send_time=_parse_dt(send_time),
         arrival_time=_parse_dt(arrival_time),
         sender_name=sender_name or None,
@@ -731,6 +824,7 @@ def postcard_update(
     status: str = Form(...),
     recipient_name: str = Form(""),
     country: str = Form(""),
+    country_from: str = Form(""),
     send_time: str = Form(""),
     arrival_time: str = Form(""),
     sender_name: str = Form(""),
@@ -749,7 +843,10 @@ def postcard_update(
         return _redirect("/profiles")
 
     cn = card_number.strip()
-    dup = db.query(Postcard).filter(Postcard.card_number == cn, Postcard.id != postcard_id).first()
+    dup = db.query(Postcard).join(Profile).filter(
+        Postcard.card_number == cn, Postcard.id != postcard_id,
+        Profile.user_id == user.id
+    ).first()
     if dup:
         return templates.TemplateResponse("postcard_form.html", {
             "request": request, "user": user, "profile": pc.profile, "postcard": pc,
@@ -772,6 +869,7 @@ def postcard_update(
     pc.status = status
     pc.recipient_name = recipient_name or None
     pc.country = country or None
+    pc.country_from = country_from.strip().upper() if country_from else pc.country_from
     pc.send_time = _parse_dt(send_time)
     pc.arrival_time = None if status == "sent" else _parse_dt(arrival_time)
     pc.sender_name = sender_name or None
@@ -925,7 +1023,10 @@ def public_showcase(request: Request, username: str, db: Session = Depends(get_d
     profiles = db.query(Profile).filter(Profile.user_id == user.id, Profile.showcase_enabled == True).all()
     sent_all, received_all, profile_groups = [], [], []
     for p in profiles:
-        cards = db.query(Postcard).filter(Postcard.profile_id == p.id, Postcard.showcase_hidden == False).all()
+        cards = db.query(Postcard).filter(
+            Postcard.profile_id == p.id, Postcard.showcase_hidden == False,
+            Postcard.image_front.isnot(None), Postcard.image_front != ""
+        ).all()
         if p.showcase_visible in ("sent", "both"):
             sent_all.extend([c for c in cards if c.status in ("sent", "delivered")])
         if p.showcase_visible in ("received", "both"):

app/schemas.py

@@ -7,11 +7,18 @@ from pydantic import BaseModel
 
 class ProfileCreate(BaseModel):
     nickname: str
+    country: str | None = None
+
+
+class ProfileUpdate(BaseModel):
+    nickname: str | None = None
+    country: str | None = None
 
 
 class ProfileOut(BaseModel):
     id: int
     nickname: str
+    country: str | None
     created_at: datetime
 
     model_config = {"from_attributes": True}
@@ -24,6 +31,7 @@ class PostcardCreate(BaseModel):
     status: str
     recipient_name: str | None = None
     country: str | None = None
+    country_from: str | None = None
     send_time: datetime | None = None
     arrival_time: datetime | None = None
     sender_name: str | None = None
@@ -35,6 +43,7 @@ class PostcardUpdate(BaseModel):
     status: str | None = None
     recipient_name: str | None = None
     country: str | None = None
+    country_from: str | None = None
     send_time: datetime | None = None
     arrival_time: datetime | None = None
     sender_name: str | None = None
@@ -48,6 +57,7 @@ class PostcardOut(BaseModel):
     status: str
     recipient_name: str | None
     country: str | None
+    country_from: str | None
     send_time: datetime | None
     arrival_time: datetime | None
     sender_name: str | None

app/templates/index.html

@@ -12,7 +12,8 @@
                 {% endfor %}
             </div>
         </div>
-        <a href="/login" class="btn btn-primary" style="margin-left:.5rem">{{ 'index.go_login'|t(lang) }}</a>
+        <a href="/login" class="btn btn-sm" style="margin-left:.5rem">{{ 'index.go_login'|t(lang) }}</a>
+        <a href="/register" class="btn btn-primary btn-sm">{{ 'index.go_register'|t(lang) }}</a>
     </div>
 </nav>
 {% endblock %}
@@ -22,25 +23,30 @@
     <p style="color:var(--text-muted);margin-top:.25rem">{{ 'index.subtitle'|t(lang) }}</p>
 </div>
 
-{% if postcards %}
+{% set visible = [] %}
-<div class="showcase-grid">
 {% for pc in postcards %}
-    <div class="showcase-card" data-front="{{ pc.image_front or '' }}" data-number="{{ pc.card_number }}" onclick="openLightbox(this)">
     {% if pc.image_front %}
-        <img src="{{ pc.image_front }}" alt="" class="showcase-card-img" loading="lazy">
+        {% if visible.append(pc) %}{% endif %}
-        {% else %}
-        <div class="showcase-card-img placeholder-img">📷</div>
     {% endif %}
+{% endfor %}
+
+{% if visible|length > 0 or has_more %}
+<div class="showcase-grid" id="showcase-grid">
+    {% for pc in visible %}
+    <div class="showcase-card" data-front="{{ pc.image_front }}" onclick="openLightbox(this)">
+        <img src="{{ pc.image_front }}" alt="" class="showcase-card-img" loading="lazy">
         <div class="showcase-card-body">
-            <strong>{{ pc.card_number }}</strong>
             <div class="showcase-card-meta">
-                <span>{{ pc.country|flag }} {{ pc.country or '' }}</span>
+                {% if pc.country_from and pc.country %}<span>{{ pc.country_from|flag }}→{{ pc.country|flag }}</span>
-                {% if pc.send_time %}<span>{{ pc.send_time.strftime('%Y-%m-%d') }}</span>{% endif %}
+                {% elif pc.country %}<span>{{ pc.country|flag }}</span>
+                {% endif %}
             </div>
         </div>
     </div>
     {% endfor %}
 </div>
+<div id="scroll-sentinel" style="height:1px"></div>
+<div id="scroll-loading" style="text-align:center;padding:1rem;color:var(--text-muted);display:none">⏳</div>
 {% else %}
 <div class="empty-state">
     <p>{{ 'index.empty'|t(lang) }}</p>
@@ -49,26 +55,116 @@
 
 <!-- Lightbox -->
 <div id="lightbox" class="lightbox" onclick="closeLightbox()" style="display:none">
-    <div class="lightbox-inner" onclick="event.stopPropagation()">
+    <div class="lightbox-content" onclick="event.stopPropagation()">
         <button class="lightbox-close" onclick="closeLightbox()">&times;</button>
+        <button class="lightbox-prev" onclick="navLightbox(-1)">&#8249;</button>
+        <button class="lightbox-next" onclick="navLightbox(1)">&#8250;</button>
         <img id="lightbox-img" src="" alt="">
-        <div id="lightbox-number" class="lightbox-number"></div>
+        <div id="lightbox-caption" class="lightbox-caption"></div>
     </div>
 </div>
 
 <script>
+/* ---- Infinite Scroll ---- */
+var _page = 1;
+var _hasMore = {{ 'true' if has_more else 'false' }};
+var _loading = false;
+
+function _appendCard(c) {
+    var grid = document.getElementById('showcase-grid');
+    if (!grid) return;
+    var div = document.createElement('div');
+    div.className = 'showcase-card';
+    div.setAttribute('data-front', c.image_front);
+    div.onclick = function() { openLightbox(div); };
+    var countryHtml = '';
+    if (c.country_from && c.country) countryHtml = '<span>' + _flag(c.country_from) + '→' + _flag(c.country) + '</span>';
+    else if (c.country) countryHtml = '<span>' + _flag(c.country) + '</span>';
+    div.innerHTML = '<img src="' + c.image_front + '" alt="" class="showcase-card-img" loading="lazy">' +
+        '<div class="showcase-card-body"><div class="showcase-card-meta">' + countryHtml + '</div></div>';
+    grid.appendChild(div);
+}
+
+function _flag(code) {
+    if (!code || code.length !== 2) return code || '';
+    return String.fromCodePoint(0x1F1E6 + code.charCodeAt(0) - 65) + String.fromCodePoint(0x1F1E6 + code.charCodeAt(1) - 65);
+}
+
+function _loadMore() {
+    if (_loading || !_hasMore) return;
+    _loading = true;
+    document.getElementById('scroll-loading').style.display = '';
+    fetch('/api/public/cards?page=' + (_page + 1) + '&limit=20')
+        .then(function(r) { return r.json(); })
+        .then(function(data) {
+            _loading = false;
+            document.getElementById('scroll-loading').style.display = 'none';
+            _page = data.page;
+            _hasMore = data.has_more;
+            data.cards.forEach(_appendCard);
+            if (!_hasMore) {
+                var s = document.getElementById('scroll-sentinel');
+                if (s) s.remove();
+            }
+        })
+        .catch(function() { _loading = false; });
+}
+
+var _observer = new IntersectionObserver(function(entries) {
+    if (entries[0].isIntersecting) _loadMore();
+}, {rootMargin: '400px'});
+var _sentinel = document.getElementById('scroll-sentinel');
+if (_sentinel) _observer.observe(_sentinel);
+
+/* ---- Lightbox ---- */
+var lightboxItems = [];
+var lightboxIdx = 0;
+
+function buildLightboxItems() {
+    lightboxItems = [];
+    document.querySelectorAll('#showcase-grid .showcase-card[data-front]').forEach(function(card) {
+        lightboxItems.push({src: card.getAttribute('data-front')});
+    });
+}
+
 function openLightbox(el) {
+    buildLightboxItems();
     var src = el.getAttribute('data-front');
     if (!src) return;
-    document.getElementById('lightbox-img').src = src;
+    for (var i = 0; i < lightboxItems.length; i++) {
-    document.getElementById('lightbox-number').textContent = el.getAttribute('data-number');
+        if (lightboxItems[i].src === src) { lightboxIdx = i; break; }
+    }
+    showLightboxItem();
     document.getElementById('lightbox').style.display = 'flex';
+    document.body.style.overflow = 'hidden';
 }
-function closeLightbox() {
+
+function showLightboxItem() {
+    if (!lightboxItems.length) return;
+    var item = lightboxItems[lightboxIdx];
+    document.getElementById('lightbox-img').src = item.src;
+    document.getElementById('lightbox-caption').textContent = (lightboxIdx+1) + '/' + lightboxItems.length;
+}
+
+function closeLightbox(e) {
+    if (e) e.stopPropagation();
     document.getElementById('lightbox').style.display = 'none';
+    document.body.style.overflow = '';
 }
+
+function navLightbox(dir, e) {
+    if (e) e.stopPropagation();
+    if (!lightboxItems.length) return;
+    lightboxIdx = (lightboxIdx + dir + lightboxItems.length) % lightboxItems.length;
+    showLightboxItem();
+}
+
 document.addEventListener('keydown', function(e) {
+    var lb = document.getElementById('lightbox');
+    if (!lb || lb.style.display === 'none') return;
     if (e.key === 'Escape') closeLightbox();
+    else if (e.key === 'ArrowLeft') navLightbox(-1);
+    else if (e.key === 'ArrowRight') navLightbox(1);
 });
 </script>
 {% endblock %}

app/templates/postcard_detail.html

@@ -52,11 +52,12 @@
             <dt>{{ 'pc_detail.status'|t(user.language) }}</dt><dd>{{ {'sent':'已寄出','delivered':'已送达','received':'已收到'}.get(postcard.status, postcard.status) if user.language=='zh' else {'sent':'Sent','delivered':'Delivered','received':'Received'}.get(postcard.status, postcard.status) }}</dd>
             {% if postcard.status in ('sent','delivered') %}
             <dt>{{ 'pc_detail.recipient'|t(user.language) }}</dt><dd>{{ postcard.recipient_name or '-' }}</dd>
-            <dt>{{ 'pc_detail.country'|t(user.language) }}</dt><dd>{{ postcard.country|flag }} {{ postcard.country or '-' }}</dd>
+            <dt>{{ 'pc_detail.route'|t(user.language) }}</dt><dd>{% if postcard.country_from %}{{ postcard.country_from|flag }} {{ postcard.country_from }} → {% endif %}{{ postcard.country|flag }} {{ postcard.country or '-' }}</dd>
             <dt>{{ 'pc_detail.send_time'|t(user.language) }}</dt><dd>{{ postcard.send_time.strftime('%Y-%m-%d') if postcard.send_time else '-' }}</dd>
             <dt>{{ 'pc_detail.arrival_time'|t(user.language) }}</dt><dd>{{ postcard.arrival_time.strftime('%Y-%m-%d') if postcard.arrival_time else '-' }}</dd>
             {% else %}
             <dt>{{ 'pc_detail.sender'|t(user.language) }}</dt><dd>{{ postcard.sender_name or '-' }}</dd>
+            <dt>{{ 'pc_detail.route'|t(user.language) }}</dt><dd>{% if postcard.country_from %}{{ postcard.country_from|flag }} {{ postcard.country_from }} → {% endif %}{{ postcard.country|flag }} {{ postcard.country or '-' }}</dd>
             <dt>{{ 'pc_detail.receive_time'|t(user.language) }}</dt><dd>{{ postcard.receive_time.strftime('%Y-%m-%d') if postcard.receive_time else '-' }}</dd>
             {% endif %}
             <dt>{{ 'pc_detail.profile'|t(user.language) }}</dt><dd>{{ postcard.profile.nickname }}</dd>

app/templates/postcard_form.html

@@ -18,8 +18,6 @@
     <div id="fields-sent-delivered">
         <label>{{ 'pc_form.recipient'|t(user.language) }} *</label>
         <input type="text" name="recipient_name" id="input-recipient" value="{{ postcard.recipient_name if postcard else '' }}">
-        <label>{{ 'pc_form.country'|t(user.language) }} *</label>
-        <input type="text" name="country" id="input-country" value="{{ postcard.country if postcard else '' }}" maxlength="2" placeholder="JP" style="width:80px;text-transform:uppercase" oninput="this.value=this.value.toUpperCase()">
         <label>{{ 'pc_form.send_time'|t(user.language) }} *</label>
         <input type="date" name="send_time" id="input-send-time" value="{{ postcard.send_time.strftime('%Y-%m-%d') if postcard and postcard.send_time else '' }}">
         <label id="label-arrival">{{ 'pc_form.arrival_time'|t(user.language) }}</label>
@@ -33,6 +31,12 @@
         <input type="date" name="receive_time" id="input-receive" value="{{ postcard.receive_time.strftime('%Y-%m-%d') if postcard and postcard.receive_time else '' }}">
     </div>
 
+    <label>{{ 'pc_form.country_from'|t(user.language) }}</label>
+    <input type="text" name="country_from" id="input-country-from" value="{{ postcard.country_from if postcard and postcard.country_from else (profile.country if profile else '') }}" maxlength="2" style="width:80px;text-transform:uppercase" oninput="this.value=this.value.toUpperCase()">
+
+    <label>{{ 'pc_form.country'|t(user.language) }} *</label>
+    <input type="text" name="country" id="input-country" value="{{ postcard.country if postcard else '' }}" maxlength="2" placeholder="JP" style="width:80px;text-transform:uppercase" oninput="this.value=this.value.toUpperCase()">
+
     <label>{{ 'pc_form.notes'|t(user.language) }}</label>
     <textarea name="notes" rows="3" placeholder="{{ 'pc_form.notes_ph'|t(user.language) }}">{{ postcard.notes if postcard else '' }}</textarea>
 

app/templates/postcards.html

@@ -41,7 +41,7 @@
     <div class="postcard-row-info">
         <strong>{{ pc.card_number }}</strong>
         <div class="postcard-row-detail">
-            <span>{{ pc.country|flag }} {{ pc.country or '-' }}</span>
+            <span>{% if pc.country_from %}{{ pc.country_from|flag }}→{% endif %}{{ pc.country|flag }} {{ pc.country or '-' }}</span>
             <span>→ {{ pc.recipient_name or '-' }}</span>
         </div>
         <span class="badge badge-{{ pc.status }}">{{ {'sent':'已寄出','delivered':'已送达'}.get(pc.status) if user.language=='zh' else {'sent':'Sent','delivered':'Delivered'}.get(pc.status) }}</span>

app/templates/profiles.html

@@ -7,6 +7,7 @@
 <div class="inline-form">
     <form method="post" action="/profiles" class="form-row">
         <input type="text" name="nickname" placeholder="{{ 'profiles.new_ph'|t(user.language) }}" required>
+        <input type="text" name="country" placeholder="{{ 'profiles.country_ph'|t(user.language) }}" maxlength="2" style="width:60px;text-transform:uppercase" oninput="this.value=this.value.toUpperCase()">
         <button type="submit" class="btn btn-primary">{{ 'profiles.new_btn'|t(user.language) }}</button>
     </form>
 </div>
@@ -18,10 +19,12 @@
         <div class="profile-card-header">
             <h3 class="profile-card-name">
                 <span id="name-display-{{ p.id }}">{{ p.nickname }}</span>
+                {% if p.country %}<span style="font-size:.8rem;color:var(--text-muted);font-weight:400">{{ p.country|flag }} {{ p.country }}</span>{% endif %}
                 <button type="button" class="icon-btn" onclick="startRename({{ p.id }})" title="{{ 'profiles.rename'|t(user.language) }}">✏️</button>
             </h3>
             <form method="post" action="/profiles/{{ p.id }}/rename" class="rename-form" id="name-edit-{{ p.id }}" style="display:none">
                 <input type="text" name="nickname" value="{{ p.nickname }}" required>
+                <input type="text" name="country" value="{{ p.country or '' }}" maxlength="2" style="width:60px;text-transform:uppercase" oninput="this.value=this.value.toUpperCase()" placeholder="{{ 'profiles.country_ph'|t(user.language) }}">
                 <button type="submit" class="btn btn-primary btn-sm">✓</button>
                 <button type="button" class="btn btn-sm" onclick="cancelRename({{ p.id }})">✕</button>
             </form>

app/templates/showcase.html

@@ -16,7 +16,20 @@
     <h1>📮 {{ profile_user.username }} {{ 'showcase.title'|t(lang) }}</h1>
 </div>
 
-{% set has_content = (sent_all|length + received_all|length) > 0 %}
+{% set sent_visible = [] %}
+{% set received_visible = [] %}
+{% for pc in sent_all %}
+    {% if pc.image_front %}
+        {% if sent_visible.append(pc) %}{% endif %}
+    {% endif %}
+{% endfor %}
+{% for pc in received_all %}
+    {% if pc.image_front %}
+        {% if received_visible.append(pc) %}{% endif %}
+    {% endif %}
+{% endfor %}
+
+{% set has_content = (sent_visible|length + received_visible|length) > 0 %}
 {% if not has_content %}
 <div class="empty-state">
     <p>{{ 'showcase.empty'|t(lang) }}</p>
@@ -24,25 +37,21 @@
 {% else %}
 
 <div class="tabs" id="tabs">
-    <button class="tab active" onclick="switchTab('sent')">{{ 'showcase.tab_sent'|t(lang) }} ({{ sent_all|length }})</button>
+    <button class="tab active" onclick="switchTab('sent')">{{ 'showcase.tab_sent'|t(lang) }} ({{ sent_visible|length }})</button>
-    <button class="tab" onclick="switchTab('received')">{{ 'showcase.tab_received'|t(lang) }} ({{ received_all|length }})</button>
+    <button class="tab" onclick="switchTab('received')">{{ 'showcase.tab_received'|t(lang) }} ({{ received_visible|length }})</button>
 </div>
 
 <div id="tab-sent" class="tab-panel">
 {% if mode == 'flat' %}
-    <div class="showcase-grid">
+    <div class="showcase-grid" id="grid-sent">
-    {% for pc in sent_all %}
+    {% for pc in sent_visible %}
-        <div class="showcase-card" data-front="{{ pc.image_front or '' }}" data-number="{{ pc.card_number }}" onclick="openLightbox(this)">
+        <div class="showcase-card" data-front="{{ pc.image_front }}" onclick="openLightbox(this)">
-            {% if pc.image_front %}
             <img src="{{ pc.image_front }}" alt="" class="showcase-card-img" loading="lazy">
-            {% else %}
-            <div class="showcase-card-img placeholder-img">📷</div>
-            {% endif %}
             <div class="showcase-card-body">
-                <strong>{{ pc.card_number }}</strong>
                 <div class="showcase-card-meta">
-                    <span>{{ pc.country|flag }} {{ pc.country or '' }}</span>
+                    {% if pc.country_from and pc.country %}<span>{{ pc.country_from|flag }}→{{ pc.country|flag }}</span>
-                    {% if pc.send_time %}<span>{{ pc.send_time.strftime('%Y-%m-%d') }}</span>{% endif %}
+                    {% elif pc.country %}<span>{{ pc.country|flag }}</span>
+                    {% endif %}
                 </div>
             </div>
         </div>
@@ -50,21 +59,23 @@
     </div>
 {% else %}
     {% for g in profile_groups %}
-    {% if g.sent %}
+    {% set g_sent = [] %}
+    {% for pc in g.sent %}
+        {% if pc.image_front %}
+            {% if g_sent.append(pc) %}{% endif %}
+        {% endif %}
+    {% endfor %}
+    {% if g_sent %}
     <h3 style="margin:1rem 0 .75rem;font-size:.95rem;color:var(--text-muted)">{{ g.profile.nickname }}</h3>
     <div class="showcase-grid">
-        {% for pc in g.sent %}
+        {% for pc in g_sent %}
-        <div class="showcase-card" data-front="{{ pc.image_front or '' }}" data-number="{{ pc.card_number }}" onclick="openLightbox(this)">
+        <div class="showcase-card" data-front="{{ pc.image_front }}" onclick="openLightbox(this)">
-            {% if pc.image_front %}
             <img src="{{ pc.image_front }}" alt="" class="showcase-card-img" loading="lazy">
-            {% else %}
-            <div class="showcase-card-img placeholder-img">📷</div>
-            {% endif %}
             <div class="showcase-card-body">
-                <strong>{{ pc.card_number }}</strong>
                 <div class="showcase-card-meta">
-                    <span>{{ pc.country|flag }} {{ pc.country or '' }}</span>
+                    {% if pc.country_from and pc.country %}<span>{{ pc.country_from|flag }}→{{ pc.country|flag }}</span>
-                    {% if pc.send_time %}<span>{{ pc.send_time.strftime('%Y-%m-%d') }}</span>{% endif %}
+                    {% elif pc.country %}<span>{{ pc.country|flag }}</span>
+                    {% endif %}
                 </div>
             </div>
         </div>
@@ -73,23 +84,21 @@
     {% endif %}
     {% endfor %}
 {% endif %}
+<div id="scroll-sentinel-sent" style="height:1px"></div>
+<div id="scroll-loading-sent" style="text-align:center;padding:1rem;color:var(--text-muted);display:none">⏳</div>
 </div>
 
 <div id="tab-received" class="tab-panel" style="display:none">
 {% if mode == 'flat' %}
-    <div class="showcase-grid">
+    <div class="showcase-grid" id="grid-received">
-    {% for pc in received_all %}
+    {% for pc in received_visible %}
-        <div class="showcase-card" data-front="{{ pc.image_front or '' }}" data-number="{{ pc.card_number }}" onclick="openLightbox(this)">
+        <div class="showcase-card" data-front="{{ pc.image_front }}" onclick="openLightbox(this)">
-            {% if pc.image_front %}
             <img src="{{ pc.image_front }}" alt="" class="showcase-card-img" loading="lazy">
-            {% else %}
-            <div class="showcase-card-img placeholder-img">📷</div>
-            {% endif %}
             <div class="showcase-card-body">
-                <strong>{{ pc.card_number }}</strong>
                 <div class="showcase-card-meta">
-                    <span>{{ pc.country|flag }} {{ pc.country or '' }}</span>
+                    {% if pc.country_from and pc.country %}<span>{{ pc.country_from|flag }}→{{ pc.country|flag }}</span>
-                    {% if pc.receive_time %}<span>{{ pc.receive_time.strftime('%Y-%m-%d') }}</span>{% endif %}
+                    {% elif pc.country %}<span>{{ pc.country|flag }}</span>
+                    {% endif %}
                 </div>
             </div>
         </div>
@@ -97,21 +106,23 @@
     </div>
 {% else %}
     {% for g in profile_groups %}
-    {% if g.received %}
+    {% set g_received = [] %}
+    {% for pc in g.received %}
+        {% if pc.image_front %}
+            {% if g_received.append(pc) %}{% endif %}
+        {% endif %}
+    {% endfor %}
+    {% if g_received %}
     <h3 style="margin:1rem 0 .75rem;font-size:.95rem;color:var(--text-muted)">{{ g.profile.nickname }}</h3>
     <div class="showcase-grid">
-        {% for pc in g.received %}
+        {% for pc in g_received %}
-        <div class="showcase-card" data-front="{{ pc.image_front or '' }}" data-number="{{ pc.card_number }}" onclick="openLightbox(this)">
+        <div class="showcase-card" data-front="{{ pc.image_front }}" onclick="openLightbox(this)">
-            {% if pc.image_front %}
             <img src="{{ pc.image_front }}" alt="" class="showcase-card-img" loading="lazy">
-            {% else %}
-            <div class="showcase-card-img placeholder-img">📷</div>
-            {% endif %}
             <div class="showcase-card-body">
-                <strong>{{ pc.card_number }}</strong>
                 <div class="showcase-card-meta">
-                    <span>{{ pc.country|flag }} {{ pc.country or '' }}</span>
+                    {% if pc.country_from and pc.country %}<span>{{ pc.country_from|flag }}→{{ pc.country|flag }}</span>
-                    {% if pc.receive_time %}<span>{{ pc.receive_time.strftime('%Y-%m-%d') }}</span>{% endif %}
+                    {% elif pc.country %}<span>{{ pc.country|flag }}</span>
+                    {% endif %}
                 </div>
             </div>
         </div>
@@ -120,20 +131,88 @@
     {% endif %}
     {% endfor %}
 {% endif %}
+<div id="scroll-sentinel-received" style="height:1px"></div>
+<div id="scroll-loading-received" style="text-align:center;padding:1rem;color:var(--text-muted);display:none">⏳</div>
 </div>
 {% endif %}
 
 <div id="lightbox" class="lightbox" onclick="closeLightbox(event)">
-    <button class="lightbox-close" onclick="closeLightbox(event)">&times;</button>
-    <button class="lightbox-prev" onclick="navLightbox(-1,event)">&#10094;</button>
-    <button class="lightbox-next" onclick="navLightbox(1,event)">&#10095;</button>
     <div class="lightbox-content" onclick="event.stopPropagation()">
+        <button class="lightbox-close" onclick="closeLightbox(event)">&times;</button>
+        <button class="lightbox-prev" onclick="navLightbox(-1,event)">&#8249;</button>
+        <button class="lightbox-next" onclick="navLightbox(1,event)">&#8250;</button>
         <img id="lightbox-img" src="" alt="">
         <div id="lightbox-caption" class="lightbox-caption"></div>
     </div>
 </div>
 
 <script>
+var _username = '{{ profile_user.username }}';
+var _sentPage = 1, _sentMore = {{ 'true' if sent_visible|length > 19 else 'false' }};
+var _recvPage = 1, _recvMore = {{ 'true' if received_visible|length > 19 else 'false' }};
+var _sentLoading = false, _recvLoading = false;
+
+function _flag(code) {
+    if (!code || code.length !== 2) return code || '';
+    return String.fromCodePoint(0x1F1E6 + code.charCodeAt(0) - 65) + String.fromCodePoint(0x1F1E6 + code.charCodeAt(1) - 65);
+}
+
+function _appendCard(c, gridId) {
+    var grid = document.getElementById(gridId);
+    if (!grid) return;
+    var div = document.createElement('div');
+    div.className = 'showcase-card';
+    div.setAttribute('data-front', c.image_front);
+    div.onclick = function() { openLightbox(div); };
+    var countryHtml = '';
+    if (c.country_from && c.country) countryHtml = '<span>' + _flag(c.country_from) + '→' + _flag(c.country) + '</span>';
+    else if (c.country) countryHtml = '<span>' + _flag(c.country) + '</span>';
+    div.innerHTML = '<img src="' + c.image_front + '" alt="" class="showcase-card-img" loading="lazy">' +
+        '<div class="showcase-card-body"><div class="showcase-card-meta">' + countryHtml + '</div></div>';
+    grid.appendChild(div);
+}
+
+function _loadMoreSent() {
+    if (_sentLoading || !_sentMore) return;
+    _sentLoading = true;
+    document.getElementById('scroll-loading-sent').style.display = '';
+    fetch('/api/public/cards/' + _username + '?page=' + (_sentPage + 1) + '&limit=20&tab=sent')
+        .then(function(r) { return r.json(); })
+        .then(function(data) {
+            _sentLoading = false;
+            document.getElementById('scroll-loading-sent').style.display = 'none';
+            _sentPage = data.page;
+            _sentMore = data.has_more;
+            data.cards.forEach(function(c) { _appendCard(c, 'grid-sent'); });
+            if (!_sentMore) { var s = document.getElementById('scroll-sentinel-sent'); if (s) s.remove(); }
+        })
+        .catch(function() { _sentLoading = false; });
+}
+
+function _loadMoreReceived() {
+    if (_recvLoading || !_recvMore) return;
+    _recvLoading = true;
+    document.getElementById('scroll-loading-received').style.display = '';
+    fetch('/api/public/cards/' + _username + '?page=' + (_recvPage + 1) + '&limit=20&tab=received')
+        .then(function(r) { return r.json(); })
+        .then(function(data) {
+            _recvLoading = false;
+            document.getElementById('scroll-loading-received').style.display = 'none';
+            _recvPage = data.page;
+            _recvMore = data.has_more;
+            data.cards.forEach(function(c) { _appendCard(c, 'grid-received'); });
+            if (!_recvMore) { var s = document.getElementById('scroll-sentinel-received'); if (s) s.remove(); }
+        })
+        .catch(function() { _recvLoading = false; });
+}
+
+var _obsSent = new IntersectionObserver(function(e) { if (e[0].isIntersecting) _loadMoreSent(); }, {rootMargin: '400px'});
+var _obsRecv = new IntersectionObserver(function(e) { if (e[0].isIntersecting) _loadMoreReceived(); }, {rootMargin: '400px'});
+var _sSent = document.getElementById('scroll-sentinel-sent');
+var _sRecv = document.getElementById('scroll-sentinel-received');
+if (_sSent) _obsSent.observe(_sSent);
+if (_sRecv) _obsRecv.observe(_sRecv);
+
 function switchTab(name) {
     document.querySelectorAll('.tab').forEach(function(t) { t.classList.remove('active'); });
     document.querySelectorAll('.tab-panel').forEach(function(p) { p.style.display = 'none'; });
@@ -149,8 +228,7 @@ function buildLightboxItems() {
     var visible = document.querySelectorAll('.tab-panel:not([style*="display:none"]) .showcase-card[data-front]');
     visible.forEach(function(card) {
         var front = card.getAttribute('data-front');
-        var number = card.getAttribute('data-number');
+        if (front) lightboxItems.push({src: front});
-        if (front) lightboxItems.push({src: front, number: number});
     });
 }
 
@@ -158,9 +236,8 @@ function openLightbox(el) {
     buildLightboxItems();
     var front = el.getAttribute('data-front');
     if (!front) return;
-    var number = el.getAttribute('data-number');
     for (var i = 0; i < lightboxItems.length; i++) {
-        if (lightboxItems[i].number === number) { lightboxIdx = i; break; }
+        if (lightboxItems[i].src === front) { lightboxIdx = i; break; }
     }
     showLightboxItem();
     document.getElementById('lightbox').classList.add('active');
@@ -171,7 +248,7 @@ function showLightboxItem() {
     if (!lightboxItems.length) return;
     var item = lightboxItems[lightboxIdx];
     document.getElementById('lightbox-img').src = item.src;
-    document.getElementById('lightbox-caption').textContent = item.number + ' (' + (lightboxIdx+1) + '/' + lightboxItems.length + ')';
+    document.getElementById('lightbox-caption').textContent = (lightboxIdx+1) + '/' + lightboxItems.length;
 }
 
 function closeLightbox(e) {
@@ -194,13 +271,10 @@ document.addEventListener('keydown', function(e) {
     else if (e.key === 'ArrowLeft') navLightbox(-1);
     else if (e.key === 'ArrowRight') navLightbox(1);
 });
-// Close language dropdown when clicking outside
 document.addEventListener('click', function(e) {
     var sw = document.getElementById('langSwitcher');
     var dd = document.getElementById('langDropdown');
-    if (sw && dd && !sw.contains(e.target)) {
+    if (sw && dd && !sw.contains(e.target)) dd.classList.remove('show');
-        dd.classList.remove('show');
-    }
 });
 </script>
 {% endblock %}