"""Social graph: profiles, swipes, matches, DMs — file-backed store."""

from __future__ import annotations

import json
import secrets
import time
from datetime import datetime, timezone, timedelta
from pathlib import Path
from typing import Any

from app.data.social_profiles import CANDIDATE_PROFILES, MATCH_INTENTS

STORE_PATH = Path(__file__).resolve().parents[1] / "data" / "social_store.json"

LIKE_ACTIONS = frozenset({"like", "right", "superlike"})
FREE_SWIPE_DAILY_LIMIT = 25
VIP_SWIPE_LIMIT = 9999

_profiles: dict[str, dict] = {}  # user_id -> profile
_swipes: list[dict] = []
_matches: list[dict] = []
_conversations: list[dict] = []
_messages: list[dict] = []
_memberships: dict[str, dict] = {}  # user_id -> {expires_at, plan}
_orders: dict[str, dict] = {}


def _now_iso() -> str:
  return datetime.now(timezone.utc).isoformat()


def _today_key() -> str:
  return datetime.now(timezone(timedelta(hours=8))).strftime("%Y-%m-%d")


def _persist() -> None:
  STORE_PATH.parent.mkdir(parents=True, exist_ok=True)
  STORE_PATH.write_text(
    json.dumps({
      "profiles": _profiles,
      "swipes": _swipes,
      "matches": _matches,
      "conversations": _conversations,
      "messages": _messages,
      "memberships": _memberships,
      "orders": _orders,
    }, ensure_ascii=False),
    encoding="utf-8",
  )


def _restore() -> None:
  global _profiles, _swipes, _matches, _conversations, _messages, _memberships, _orders
  if not STORE_PATH.exists():
    return
  try:
    data = json.loads(STORE_PATH.read_text(encoding="utf-8"))
  except (OSError, json.JSONDecodeError):
    return
  _profiles = data.get("profiles") or {}
  _swipes = data.get("swipes") or []
  _matches = data.get("matches") or []
  _conversations = data.get("conversations") or []
  _messages = data.get("messages") or []
  _memberships = data.get("memberships") or {}
  _orders = data.get("orders") or {}


_restore()


def _reload() -> None:
  _restore()


def is_vip(user_id: str) -> bool:
  _reload()
  m = _memberships.get(user_id)
  if not m:
    return False
  exp = m.get("expires_at") or 0
  return exp > int(time.time())


def ensure_membership(user_id: str, days: int = 365) -> None:
  _memberships[user_id] = {
    "plan": "vip",
    "expires_at": int(time.time()) + days * 86400,
    "updated_at": _now_iso(),
  }
  _persist()


def get_or_create_profile(user_id: str, name: str, **extra: Any) -> dict:
  if user_id not in _profiles:
    _profiles[user_id] = {
      "userId": user_id,
      "name": name,
      "location": extra.get("location", "全球"),
      "citySlug": extra.get("citySlug", ""),
      "gender": extra.get("gender", ""),
      "single": extra.get("single", ""),
      "bio": extra.get("bio", ""),
      "photo": extra.get("photo", "🧑‍💻"),
      "tags": extra.get("tags", []),
      "lookingFor": extra.get("lookingFor", ["friends", "explore"]),
      "createdAt": _now_iso(),
    }
    _persist()
  return _profiles[user_id]


def join_member(user_id: str, name: str, payload: dict) -> dict:
  _reload()
  profile = get_or_create_profile(
    user_id,
    name,
    location=payload.get("city", "全球"),
    citySlug=payload.get("citySlug", ""),
    gender=payload.get("gender", ""),
    single=payload.get("single", ""),
    bio=payload.get("bio", ""),
    lookingFor=payload.get("lookingFor", ["friends", "explore"]),
    photo=payload.get("photo", "🧑‍💻"),
  )
  _persist()
  return profile


def _profile_looking_for(record: dict) -> list[str]:
  raw = record.get("lookingFor") or []
  cleaned = [x for x in raw if x in MATCH_INTENTS]
  return cleaned or ["friends", "explore"]


def list_candidates(
  user_id: str,
  intent: str = "friends",
  city: str = "",
  gender: str = "",
  single: str = "",
  exclude_swiped: bool = True,
) -> list[dict]:
  _reload()
  my_profile = _profiles.get(user_id)
  swiped_ids = set()
  if exclude_swiped:
    for s in _swipes:
      if s.get("userId") == user_id:
        swiped_ids.add(s.get("profileId"))

  pool = list(CANDIDATE_PROFILES)
  if my_profile:
    pool = [p for p in pool if p.get("userId") != user_id]

  results = []
  for p in pool:
    if p["id"] in swiped_ids:
      continue
    if intent and intent not in _profile_looking_for(p):
      continue
    if city and city not in (p.get("location") or "") and city != p.get("citySlug"):
      continue
    if gender and is_vip(user_id) and gender and p.get("gender") != gender:
      continue
    if single and is_vip(user_id) and single and p.get("single") != single:
      continue
    results.append({**p, "intent": intent})
  return results


def swipe_count_today(user_id: str) -> int:
  today = _today_key()
  return sum(1 for s in _swipes if s.get("userId") == user_id and s.get("date") == today)


def get_quota(user_id: str) -> dict:
  _reload()
  vip = is_vip(user_id)
  limit = VIP_SWIPE_LIMIT if vip else FREE_SWIPE_DAILY_LIMIT
  used = swipe_count_today(user_id)
  return {"vip": vip, "limit": limit, "used": used, "remaining": max(0, limit - used)}


def _pair_key(a: str, b: str) -> str:
  return "|".join(sorted([a, b]))


def _has_reciprocal_like(target_user_id: str, my_profile_id: str) -> bool:
  target_profile = next((p for p in CANDIDATE_PROFILES if p.get("userId") == target_user_id), None)
  if not target_profile:
    return False
  target_pid = target_profile["id"]
  for s in _swipes:
    if s.get("userId") == target_user_id and s.get("profileId") == my_profile_id:
      if s.get("action") in LIKE_ACTIONS:
        return True
  return False


def _ensure_match(user_id: str, profile: dict, intent: str) -> dict | None:
  target_uid = profile.get("userId")
  if not target_uid:
    return None
  pk = _pair_key(user_id, target_uid)
  for m in _matches:
    if m.get("pairKey") == pk:
      return m
  conv = _ensure_conversation(user_id, target_uid, intent=intent, match=True)
  match = {
    "id": secrets.token_hex(6),
    "pairKey": pk,
    "userAId": user_id,
    "userBId": target_uid,
    "profileAId": _profiles.get(user_id, {}).get("id", ""),
    "profileBId": profile.get("id"),
    "intent": intent,
    "conversationId": conv["id"],
    "matchedAt": _now_iso(),
  }
  _matches.append(match)
  _persist()
  return match


def _ensure_conversation(user_a: str, user_b: str, intent: str = "friends", match: bool = False) -> dict:
  pk = _pair_key(user_a, user_b)
  for c in _conversations:
    if c.get("pairKey") == pk:
      return c
  conv = {
    "id": secrets.token_hex(8),
    "pairKey": pk,
    "type": "match" if match else "direct",
    "userAId": user_a,
    "userBId": user_b,
    "intent": intent,
    "lastMessageAt": _now_iso(),
    "lastMessagePreview": "",
    "readState": {user_a: _now_iso(), user_b: _now_iso()},
  }
  _conversations.append(conv)
  _persist()
  return conv


def record_swipe(user_id: str, profile_id: str, action: str, intent: str) -> dict:
  _reload()
  if action not in LIKE_ACTIONS and action != "dislike":
    action = "dislike"
  if action == "superlike" and not is_vip(user_id):
    return {"ok": False, "error": "vip_required"}
  q = get_quota(user_id)
  if not q["vip"] and q["remaining"] <= 0 and action in LIKE_ACTIONS:
    return {"ok": False, "error": "quota_exceeded"}

  for s in _swipes:
    if s.get("userId") == user_id and s.get("profileId") == profile_id:
      return {"ok": False, "error": "duplicate"}

  profile = next((p for p in CANDIDATE_PROFILES if p["id"] == profile_id), None)
  if not profile:
    return {"ok": False, "error": "not_found"}

  _swipes.append({
    "id": secrets.token_hex(6),
    "userId": user_id,
    "profileId": profile_id,
    "action": action,
    "intent": intent,
    "date": _today_key(),
    "createdAt": _now_iso(),
  })
  _persist()

  matched = None
  if action in LIKE_ACTIONS and _has_reciprocal_like(profile.get("userId", ""), profile_id):
    matched = _ensure_match(user_id, profile, intent)
    if matched:
      from app.services import community_store

      my_name = _profiles.get(user_id, {}).get("name", "游民")
      peer_name = profile.get("name", "游民")
      conv_id = matched.get("conversationId", "")
      link = f"/chat/{conv_id}" if conv_id else "/chat"
      community_store.add_notification(
        user_id, "匹配成功 🎉", f"你和 {peer_name} 互相喜欢了，快去聊天吧", link
      )
      peer_uid = profile.get("userId")
      if peer_uid:
        community_store.add_notification(
          peer_uid, "匹配成功 🎉", f"你和 {my_name} 互相喜欢了，快去聊天吧", link
        )

  return {
    "ok": True,
    "matched": bool(matched),
    "match": matched,
  }


def get_public_profile(user_id: str) -> dict | None:
  _reload()
  p = _profiles.get(user_id)
  if not p:
    return None
  return {**p, "vip": is_vip(user_id)}


def undo_last_swipe(user_id: str) -> dict:
  _reload()
  for i in range(len(_swipes) - 1, -1, -1):
    if _swipes[i].get("userId") == user_id:
      removed = _swipes.pop(i)
      _persist()
      return {"ok": True, "removed": removed}
  return {"ok": False, "error": "nothing_to_undo"}


def list_likes(user_id: str) -> list[dict]:
  _reload()
  liked_ids = [s["profileId"] for s in _swipes if s.get("userId") == user_id and s.get("action") in LIKE_ACTIONS]
  return [p for p in CANDIDATE_PROFILES if p["id"] in liked_ids]


def list_mutual(user_id: str) -> list[dict]:
  _reload()
  items = []
  for m in _matches:
    if user_id in (m.get("userAId"), m.get("userBId")):
      peer_id = m["userBId"] if m["userAId"] == user_id else m["userAId"]
      peer = next((p for p in CANDIDATE_PROFILES if p.get("userId") == peer_id), None)
      items.append({**m, "peer": peer, "conversationId": m.get("conversationId")})
  return items


def list_conversations(user_id: str) -> list[dict]:
  _reload()
  items = []
  for c in _conversations:
    if user_id not in (c.get("userAId"), c.get("userBId")):
      continue
    peer_id = c["userBId"] if c["userAId"] == user_id else c["userAId"]
    peer = next((p for p in CANDIDATE_PROFILES if p.get("userId") == peer_id), None)
    read_at = (c.get("readState") or {}).get(user_id, "")
    unread = 1 if c.get("lastMessageAt", "") > read_at else 0
    items.append({
      **c,
      "peer": peer,
      "unreadCount": unread,
    })
  items.sort(key=lambda x: x.get("lastMessageAt", ""), reverse=True)
  return items


def get_conversation(conv_id: str, user_id: str) -> dict | None:
  for c in _conversations:
    if c["id"] == conv_id and user_id in (c.get("userAId"), c.get("userBId")):
      peer_id = c["userBId"] if c["userAId"] == user_id else c["userAId"]
      peer = next((p for p in CANDIDATE_PROFILES if p.get("userId") == peer_id), None)
      return {**c, "peer": peer}
  return None


def list_messages(conv_id: str, user_id: str, limit: int = 50) -> list[dict]:
  _reload()
  conv = get_conversation(conv_id, user_id)
  if not conv:
    return []
  msgs = [m for m in _messages if m.get("conversationId") == conv_id]
  msgs.sort(key=lambda x: x.get("createdAt", ""))
  if conv.get("readState") is not None:
    conv["readState"][user_id] = _now_iso()
    _persist()
  return [{**m, "mine": m.get("senderId") == user_id} for m in msgs[-limit:]]


def send_message(conv_id: str, user_id: str, body: str) -> dict | None:
  conv = get_conversation(conv_id, user_id)
  if not conv or not body.strip():
    return None
  body = body.strip()[:2000]
  msg = {
    "id": secrets.token_hex(8),
    "conversationId": conv_id,
    "senderId": user_id,
    "body": body,
    "createdAt": _now_iso(),
  }
  _messages.append(msg)
  for c in _conversations:
    if c["id"] == conv_id:
      c["lastMessageAt"] = _now_iso()
      c["lastMessagePreview"] = body[:80]
      break
  _persist()
  return {**msg, "mine": True}


def create_order(user_id: str, pay_type: str, amount: int, dev_auto_pay: bool = False) -> dict:
  order_id = f"{user_id}_{pay_type}_order_{int(time.time())}_{secrets.token_hex(2)}"
  status = "paid" if dev_auto_pay else "pending"
  order = {
    "id": order_id,
    "userId": user_id,
    "payType": pay_type,
    "amount": amount,
    "status": status,
    "createdAt": _now_iso(),
  }
  _orders[order_id] = order
  if dev_auto_pay:
    ensure_membership(user_id)
  _persist()
  return order


def get_order(order_id: str) -> dict | None:
  _reload()
  return _orders.get(order_id)


def mark_order_paid(order_id: str) -> dict | None:
  order = _orders.get(order_id)
  if not order:
    return None
  order["status"] = "paid"
  ensure_membership(order["userId"])
  _persist()
  return order