"""中控 K 线 SQLite 缓存：按需拉取、15 天滚动保留。"""

from __future__ import annotations

import os
import sqlite3
import time
from pathlib import Path
from typing import Any, Callable, Optional

from hub_ohlcv_lib import (
    TIMEFRAME_MS,
    bar_limit_for_timeframe,
    chart_fetch_start_ms,
    format_price_by_tick,
    last_closed_bar_open_ms,
    normalize_chart_timeframe,
    window_start_ms,
)

_DEFAULT_RETENTION_DAYS = 15


def retention_days() -> int:
    try:
        return max(1, int(os.getenv("HUB_KLINE_RETENTION_DAYS", str(_DEFAULT_RETENTION_DAYS))))
    except ValueError:
        return _DEFAULT_RETENTION_DAYS


def default_db_path() -> Path:
    raw = (os.getenv("HUB_KLINE_DB_PATH") or "").strip()
    if raw:
        return Path(raw)
    hub_dir = Path(__file__).resolve().parent / "manual_trading_hub" / "data"
    hub_dir.mkdir(parents=True, exist_ok=True)
    return hub_dir / "hub_kline.db"


def _connect(db_path: Path | None = None) -> sqlite3.Connection:
    path = db_path or default_db_path()
    path.parent.mkdir(parents=True, exist_ok=True)
    conn = sqlite3.connect(str(path), timeout=30, isolation_level=None)
    conn.row_factory = sqlite3.Row
    conn.execute("PRAGMA journal_mode=WAL")
    conn.execute("PRAGMA synchronous=NORMAL")
    return conn


def init_db(db_path: Path | None = None) -> None:
    conn = _connect(db_path)
    try:
        conn.execute(
            """
            CREATE TABLE IF NOT EXISTS ohlcv_bars (
                exchange_key TEXT NOT NULL,
                symbol TEXT NOT NULL,
                timeframe TEXT NOT NULL,
                open_time_ms INTEGER NOT NULL,
                open REAL NOT NULL,
                high REAL NOT NULL,
                low REAL NOT NULL,
                close REAL NOT NULL,
                volume REAL NOT NULL DEFAULT 0,
                updated_at INTEGER NOT NULL,
                PRIMARY KEY (exchange_key, symbol, timeframe, open_time_ms)
            )
            """
        )
        conn.execute(
            """
            CREATE INDEX IF NOT EXISTS idx_ohlcv_series
            ON ohlcv_bars (exchange_key, symbol, timeframe, open_time_ms)
            """
        )
    finally:
        conn.close()


def purge_retention(db_path: Path | None = None, *, days: int | None = None) -> int:
    """删除早于 retention 的 K 线；返回删除行数。"""
    keep = days if days is not None else retention_days()
    cutoff = int(time.time() * 1000) - keep * 86400000
    conn = _connect(db_path)
    try:
        cur = conn.execute("DELETE FROM ohlcv_bars WHERE open_time_ms < ?", (cutoff,))
        return int(cur.rowcount or 0)
    finally:
        conn.close()


def upsert_bars(
    exchange_key: str,
    symbol: str,
    timeframe: str,
    bars: list[dict[str, Any]],
    db_path: Path | None = None,
) -> int:
    if not bars:
        return 0
    ex_k = (exchange_key or "").strip().lower()
    sym = (symbol or "").strip().upper()
    tf = normalize_chart_timeframe(timeframe)
    now = int(time.time())
    conn = _connect(db_path)
    n = 0
    try:
        for b in bars:
            try:
                oms = int(b["open_time_ms"])
                conn.execute(
                    """
                    INSERT INTO ohlcv_bars
                    (exchange_key, symbol, timeframe, open_time_ms, open, high, low, close, volume, updated_at)
                    VALUES (?,?,?,?,?,?,?,?,?,?)
                    ON CONFLICT(exchange_key, symbol, timeframe, open_time_ms) DO UPDATE SET
                        open=excluded.open,
                        high=excluded.high,
                        low=excluded.low,
                        close=excluded.close,
                        volume=excluded.volume,
                        updated_at=excluded.updated_at
                    """,
                    (
                        ex_k,
                        sym,
                        tf,
                        oms,
                        float(b["open"]),
                        float(b["high"]),
                        float(b["low"]),
                        float(b["close"]),
                        float(b.get("volume") or 0),
                        now,
                    ),
                )
                n += 1
            except (KeyError, TypeError, ValueError):
                continue
    finally:
        conn.close()
    return n


def load_bars_range(
    exchange_key: str,
    symbol: str,
    timeframe: str,
    start_ms: int,
    end_ms: int,
    db_path: Path | None = None,
) -> list[dict[str, Any]]:
    ex_k = (exchange_key or "").strip().lower()
    sym = (symbol or "").strip().upper()
    tf = normalize_chart_timeframe(timeframe)
    conn = _connect(db_path)
    try:
        rows = conn.execute(
            """
            SELECT open_time_ms, open, high, low, close, volume
            FROM ohlcv_bars
            WHERE exchange_key=? AND symbol=? AND timeframe=?
              AND open_time_ms >= ? AND open_time_ms <= ?
            ORDER BY open_time_ms ASC
            """,
            (ex_k, sym, tf, int(start_ms), int(end_ms)),
        ).fetchall()
        return [
            {
                "open_time_ms": int(r["open_time_ms"]),
                "open": float(r["open"]),
                "high": float(r["high"]),
                "low": float(r["low"]),
                "close": float(r["close"]),
                "volume": float(r["volume"] or 0),
            }
            for r in rows
        ]
    finally:
        conn.close()


def _to_chart_candles(bars: list[dict[str, Any]]) -> list[dict[str, Any]]:
    out = []
    for b in bars:
        try:
            out.append(
                {
                    "time": int(b["open_time_ms"] // 1000),
                    "open": float(b["open"]),
                    "high": float(b["high"]),
                    "low": float(b["low"]),
                    "close": float(b["close"]),
                    "volume": float(b.get("volume") or 0),
                }
            )
        except (KeyError, TypeError, ValueError):
            continue
    return out


def _merge_bars(*groups: list[dict[str, Any]]) -> list[dict[str, Any]]:
    merged: dict[int, dict[str, Any]] = {}
    for g in groups:
        for b in g or []:
            try:
                merged[int(b["open_time_ms"])] = b
            except (KeyError, TypeError, ValueError):
                continue
    return [merged[k] for k in sorted(merged.keys())]


def resolve_chart_bars(
    exchange_key: str,
    symbol: str,
    timeframe: str,
    remote_fetch: Callable[..., dict[str, Any]],
    *,
    db_path: Path | None = None,
    force_refresh: bool = False,
) -> dict[str, Any]:
    """
    按需：先读库，不足则 remote_fetch(symbol, timeframe, since_ms, limit) 补齐并写库。
    无后台定时任务；每次调用时顺带 purge 15 天前数据。
    """
    init_db(db_path)
    purged = purge_retention(db_path)

    sym = (symbol or "").strip().upper()
    ex_k = (exchange_key or "").strip().lower()
    tf = normalize_chart_timeframe(timeframe)
    if not sym or not ex_k:
        return {"ok": False, "msg": "缺少 exchange 或 symbol"}

    need = bar_limit_for_timeframe(tf)
    now_ms = int(time.time() * 1000)
    fetch_start_ms = chart_fetch_start_ms(tf, need, now_ms)
    db_read_start_ms = window_start_ms(tf, need, retention_days(), now_ms)
    last_closed = last_closed_bar_open_ms(tf, now_ms)

    db_rows: list[dict[str, Any]] = []
    if not force_refresh:
        period_ms = TIMEFRAME_MS[tf]
        db_rows = load_bars_range(
            ex_k, sym, tf, max(0, db_read_start_ms - period_ms), now_ms + period_ms, db_path
        )

    newest_db = db_rows[-1]["open_time_ms"] if db_rows else None
    period_ms = TIMEFRAME_MS[tf]
    newest_ok = newest_db is not None and int(newest_db) >= int(last_closed) - period_ms
    need_fetch = force_refresh or len(db_rows) < need or not newest_ok

    fetched = 0
    price_tick: Optional[float] = None
    remote_err: Optional[str] = None

    if need_fetch:
        since = fetch_start_ms
        if db_rows and not force_refresh:
            since = min(since, int(db_rows[0]["open_time_ms"]))
        remote = remote_fetch(
            symbol=sym,
            timeframe=tf,
            since_ms=since,
            limit=need + 20,
        )
        if remote.get("ok") and remote.get("bars"):
            fetched = upsert_bars(ex_k, sym, tf, remote["bars"], db_path)
            price_tick = remote.get("price_tick")
            db_rows = load_bars_range(ex_k, sym, tf, fetch_start_ms, now_ms, db_path)
        else:
            remote_err = remote.get("msg") or remote.get("error") or "实例拉取 K 线失败"
            if not db_rows:
                return {"ok": False, "msg": remote_err, "purged": purged}

    if len(db_rows) > need:
        db_rows = db_rows[-need:]

    candles = _to_chart_candles(db_rows)
    if not candles:
        return {"ok": False, "msg": remote_err or "无 K 线数据", "purged": purged}

    from_cache = max(0, len(candles) - (1 if fetched else 0))
    if fetched:
        from_cache = max(0, len(candles) - min(fetched, len(candles)))

    return {
        "ok": True,
        "symbol": sym,
        "exchange_key": ex_k,
        "timeframe": tf,
        "limit": need,
        "retention_days": retention_days(),
        "candles": candles,
        "from_cache": from_cache,
        "fetched": fetched,
        "purged": purged,
        "price_tick": price_tick,
        "stale": bool(remote_err),
        "stale_message": remote_err if remote_err else None,
        "updated_at": time.strftime("%Y-%m-%d %H:%M:%S", time.localtime()),
    }


def format_ohlcv_detail(bar: dict[str, Any] | None, tick: Optional[float]) -> dict[str, str]:
    if not bar:
        return {"open": "-", "high": "-", "low": "-", "close": "-", "volume": "-"}
    return {
        "open": format_price_by_tick(bar.get("open"), tick),
        "high": format_price_by_tick(bar.get("high"), tick),
        "low": format_price_by_tick(bar.get("low"), tick),
        "close": format_price_by_tick(bar.get("close"), tick),
        "volume": format_price_by_tick(bar.get("volume"), tick),
    }