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/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)):
-    db.add(Profile(user_id=user.id, nickname=nickname))
+def profile_create(request: Request, nickname: str = Form(...), country: str = Form(""), user: User = Depends(get_current_user_web), db: Session = Depends(get_db)):
+    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"):