# -*- coding: utf-8 -*-
"""
实体链接程序（Entity Linker）—— 需求5专用程序
==============================================
作用：大模型回答生成后，用数据库实体库对回答文本做扫描匹配，
     找出其中提到的 球队 / 球员 / 人物 / 比赛 实体，供前端：
       a) 特殊标记（高亮 + 点击查看详情）
       b) 快速查看入口（回答下方卡片）
设计：
  - 纯规则 + 数据库匹配，不额外调用大模型（快、稳、零成本）
  - 最长匹配优先（"洛杉矶湖人" 优先于 "湖人"）
  - 重叠区间去重，只保留最长的命中
  - 比赛实体优先取对话中工具实际查到的比赛（game_refs），避免误匹配
  - 别名（字母哥/SGA 等）复用 tools.ALIASES
"""
import os
import re

from db import query, query_one
from tools import ALIASES

_cache = {"names": None, "games_seen": set()}


def _load_names():
    """加载实体名库：[(名字, 实体信息), ...]（按名字长度降序）
    自动生成简称：球队去掉城市前缀（波士顿凯尔特人→凯尔特人）；
    球员中文名取最后一段（谢伊·吉尔杰斯-亚历山大→亚历山大），歧义名跳过。"""
    if _cache["names"] is not None:
        return _cache["names"]
    names = []
    for t in query("SELECT id, name, name_en, code, city FROM teams"):
        info = {"type": "team", "id": t["id"], "name": t["name"]}
        for n in {t["name"], t["name_en"], t["code"]}:
            if n and len(str(n)) >= 2:
                names.append((str(n), info))
        # 简称：去掉与城市名的公共前缀（'波士顿凯尔特人'→'凯尔特人'；'俄克拉荷马雷霆'→'雷霆'）
        short = t["name"]
        if t["city"]:
            common = os.path.commonprefix([t["name"], t["city"]])
            if len(common) >= 2:
                short = t["name"][len(common):]
        if len(short) >= 2 and short != t["name"]:
            names.append((short, info))
    for p in query("SELECT id, name, name_en FROM players"):
        info = {"type": "player", "id": p["id"], "name": p["name"]}
        for n in {p["name"], p["name_en"]}:
            if n and len(str(n)) >= 2:
                names.append((str(n), info))
        # 简称：中文名按 · 分割取最后一段，再按 - 分割取最后一段
        # （'谢伊·吉尔杰斯-亚历山大' → '亚历山大'；'斯蒂芬·库里' → '库里'）
        for short in _short_names(p["name"]):
            if short:
                names.append((short, info))
    for p in query("SELECT id, name, name_en FROM persons"):
        info = {"type": "person", "id": p["id"], "name": p["name"]}
        for n in {p["name"], p["name_en"]}:
            if n and len(str(n)) >= 2:
                names.append((str(n), info))
        for short in _short_names(p["name"]):
            if short:
                names.append((short, info))
    # 别名 → 指向正式实体（球队/球员名里查找）
    for nick, real in ALIASES.items():
        target = None
        for n, info in names:
            if info["name"] == real and info["type"] in ("player", "team"):
                target = info
                break
        if target:
            names.append((nick, target))
    # 去歧义：同一简称指向多个不同实体时，全部移除（避免错误标记）
    by_name = {}
    for n, info in names:
        by_name.setdefault(n, set()).add((info["type"], info["id"]))
    names = [(n, info) for n, info in names if len(by_name[n]) == 1]
    # 按名字长度降序，保证最长匹配优先
    names.sort(key=lambda x: -len(x[0]))
    _cache["names"] = names
    return names


_ASCII_RE = re.compile(r"[A-Za-z0-9 ._'\-]+")


def _short_names(full):
    """生成中文名简称候选：按 · 和 - 逐级取最后一段
    '谢伊·吉尔杰斯-亚历山大' → ['吉尔杰斯-亚历山大', '亚历山大']
    '格雷格·波波维奇' → ['波波维奇']
    '斯蒂芬·库里' → ['库里']"""
    if not full or "·" not in full:
        return []
    seg = full.split("·")[-1].strip()
    out = []
    if len(seg) >= 2:
        out.append(seg)
        if "-" in seg:
            tail = seg.split("-")[-1].strip()
            if len(tail) >= 2 and tail != seg:
                out.append(tail)
    return out


def _find_spans(text):
    """在 text 中找出所有实体命中区间。
    返回 [{start, end, type, id, name}]，已去重叠（保留最长），按 start 升序。"""
    if not text:
        return []
    spans = []
    for n, info in _load_names():
        # 中文/混合名：直接子串查找（两边不接中文字符，避免部分词误匹配）
        if re.search(r"[\u4e00-\u9fff]", n):
            for m in re.finditer(re.escape(n), text):
                spans.append((m.start(), m.end(), info))
        else:
            # 英文/缩写：需要词边界
            for m in re.finditer(r"(?<![A-Za-z0-9])" + re.escape(n) + r"(?![A-Za-z0-9])", text, re.I):
                spans.append((m.start(), m.end(), info))
    if not spans:
        return []
    # 按 (start, -len) 排序 → 贪心取最长且不重叠
    spans.sort(key=lambda s: (s[0], -(s[1] - s[0])))
    out, last_end = [], -1
    for st, en, info in spans:
        if st >= last_end:
            out.append({"start": st, "end": en, "type": info["type"],
                        "id": info["id"], "name": info["name"]})
            last_end = en
    return out


def _match_games(text, game_refs):
    """从工具实际查到的比赛里，找出文本中提到的比赛（A队 vs B队 相邻出现）。
    返回卡片数据列表（按球队组合去重，避免系列赛多场重复）。"""
    cards, seen, seen_pair = [], set(), set()
    for g in game_refs or []:
        gid = g.get("id")
        if not gid or gid in seen:
            continue
        away, home = g.get("away_team") or "", g.get("home_team") or ""
        if not away or not home:
            continue
        pair = frozenset((away, home))
        if pair in seen_pair:      # 同一对球队只留一个卡片（优先已结束/最新）
            continue
        # 两种顺序都试：'雷霆 4-2 凯尔特人' / '凯尔特人不敌雷霆'
        hit = None
        for a, b in ((away, home), (home, away)):
            pat = re.compile(re.escape(a) + r"[^。\n，,;；]{0,12}?" + re.escape(b))
            m = pat.search(text)
            if m:
                hit = m
                break
        if hit:
            seen.add(gid)
            seen_pair.add(pair)
            cards.append({
                "type": "game", "id": gid,
                "home_team": g.get("home_team"), "away_team": g.get("away_team"),
                "home_score": g.get("home_score"), "away_score": g.get("away_score"),
                "game_time": g.get("game_time"), "status": g.get("status"),
                "round_name": g.get("round_name"),
            })
    return cards


def link_entities(text, game_refs=None, mark_mode="first"):
    """主入口：扫描回答文本。
    返回 (spans, cards)
      spans: 实体命中区间（前端高亮标记用），按 start 升序、互不重叠
             mark_mode="first" 时同一实体(type,id)只保留首次出现；"all" 时全部标记
      cards: 快速查看卡片数据（每类限量，避免刷屏）
    """
    spans = _find_spans(text or "")
    if mark_mode == "first":
        seen, kept = set(), []
        for sp in spans:          # spans 已按 start 升序 → 保留首次
            key = (sp["type"], sp["id"])
            if key in seen:
                continue
            seen.add(key)
            kept.append(sp)
        spans = kept
    cards = []
    seen_cards = set()
    for sp in spans:
        key = (sp["type"], sp["id"])
        if key in seen_cards:
            continue
        seen_cards.add(key)
        info = _card_info(sp["type"], sp["id"])
        if info:
            cards.append(info)
    cards += _match_games(text, game_refs)
    # 每类最多 4 个卡片
    by_type = {}
    for c in cards:
        by_type.setdefault(c["type"], []).append(c)
    cards = []
    for t in ("team", "player", "person", "game"):
        cards.extend(by_type.get(t, [])[:4])
    return spans, cards


def _card_info(etype, eid):
    """取实体摘要数据（前端卡片直接渲染）"""
    try:
        if etype == "team":
            t = query_one("SELECT * FROM teams WHERE id=?", (eid,))
            if not t:
                return None
            return {"type": "team", "id": t["id"], "name": t["name"], "name_en": t["name_en"],
                    "city": t["city"], "arena": t["arena"], "champion_count": t["champion_count"],
                    "head_coach": t["head_coach"]}
        if etype == "player":
            p = query_one("""SELECT p.*, t.name AS team_name FROM players p
                             LEFT JOIN teams t ON p.team_id=t.id WHERE p.id=?""", (eid,))
            if not p:
                return None
            return {"type": "player", "id": p["id"], "name": p["name"], "name_en": p["name_en"],
                    "team": p["team_name"], "position": p["position"], "number": p["number"],
                    "season": {"pts": p["season_pts"], "reb": p["season_reb"], "ast": p["season_ast"]}}
        if etype == "person":
            p = query_one("SELECT * FROM persons WHERE id=?", (eid,))
            if not p:
                return None
            return {"type": "person", "id": p["id"], "name": p["name"], "role_cn": p["role_cn"],
                    "title": p["title"]}
    except Exception:
        return None
    return None