"""Realtime Binance websocket price stream for paper trading.

The stream is intentionally separate from the cron tracker. Websocket ticks
drive paper-trading TP/SL decisions quickly, while cron remains a fallback.
"""

from __future__ import annotations

import asyncio
import json
from datetime import datetime

import websockets
from websockets.exceptions import ConnectionClosed, ConnectionClosedError, ConnectionClosedOK

from app.config.system_config import price_streamer_config
from app.db.altcoin_db import init_db, update_latest_price_cache
from app.db.paper_trading import sync_recommendation
from app.db.recommendation_queries import get_active_recommendations_deduped
from app.db.schema import get_conn
from app.db.system_logs import record_exception, record_system_error
from app.services.live_trading_sync import sync_live_protection_from_paper, sync_paper_trade_to_live


def _now() -> str:
    return datetime.now().isoformat()


_LAST_TRANSIENT_LOG_AT = 0.0
_TRANSIENT_DISCONNECT_COUNT = 0


def _safe_float(value, default=0.0) -> float:
    try:
        if value is None or value == "":
            return default
        return float(value)
    except Exception:
        return default


def _safe_int(value, default=0) -> int:
    try:
        return int(value or 0)
    except Exception:
        return default


def _stream_name(symbol: str) -> str:
    base = str(symbol or "").replace("/", "").lower()
    return f"{base}@ticker" if base else ""


def _stream_url(symbols: list[str], cfg: dict | None = None) -> str:
    cfg = cfg or price_streamer_config()
    base_url = str(cfg.get("stream_url") or "wss://stream.binance.com:9443/stream").rstrip("/")
    streams = "/".join(_stream_name(s) for s in symbols if _stream_name(s))
    return f"{base_url}?streams={streams}"


def _load_open_paper_trade_recs() -> list[dict]:
    conn = get_conn()
    try:
        rows = conn.execute(
            """
            SELECT
                p.recommendation_id AS id,
                p.symbol,
                p.entry_price,
                p.stop_loss,
                p.tp1,
                p.tp2,
                p.source_status AS execution_status,
                p.source_action AS action_status,
                p.strategy_version
            FROM paper_trades p
            WHERE p.status='open'
            ORDER BY p.opened_at DESC, p.id DESC
            """
        ).fetchall()
        return [dict(r) for r in rows]
    finally:
        conn.close()


def _load_pending_paper_order_recs() -> list[dict]:
    conn = get_conn()
    try:
        rows = conn.execute(
            """
            SELECT
                po.recommendation_id AS id,
                po.symbol,
                po.side,
                po.target_price AS entry_price,
                po.stop_loss,
                po.tp1,
                po.tp2,
                po.source_status AS execution_status,
                po.source_action AS action_status,
                po.strategy_version,
                po.strategy_code,
                po.strategy_signal_id,
                po.strategy_snapshot_json,
                po.factor_roles_json,
                po.entry_plan_snapshot_json AS entry_plan_json
            FROM paper_orders po
            WHERE po.status='pending'
            ORDER BY po.created_at DESC, po.id DESC
            """
        ).fetchall()
        return [dict(r) for r in rows]
    finally:
        conn.close()


def _load_pending_paper_order_rec(symbol: str) -> dict | None:
    symbol = str(symbol or "").strip().upper()
    if not symbol:
        return None
    conn = get_conn()
    try:
        row = conn.execute(
            """
            SELECT
                po.recommendation_id AS id,
                po.symbol,
                po.side,
                po.target_price AS entry_price,
                po.stop_loss,
                po.tp1,
                po.tp2,
                po.source_status AS execution_status,
                po.source_action AS action_status,
                po.strategy_version,
                po.strategy_code,
                po.strategy_signal_id,
                po.strategy_snapshot_json,
                po.factor_roles_json,
                po.entry_plan_snapshot_json AS entry_plan_json
            FROM paper_orders po
            WHERE po.status='pending' AND po.symbol=%s
            ORDER BY po.created_at ASC, po.id ASC
            LIMIT 1
            """,
            (symbol,),
        ).fetchone()
        return dict(row) if row else None
    finally:
        conn.close()


def load_stream_targets(limit: int | None = None, cfg: dict | None = None) -> dict[str, dict]:
    """Return symbol -> recommendation-like payload for websocket updates."""
    cfg = cfg or price_streamer_config()
    max_symbols = max(1, _safe_int(limit or cfg.get("max_stream_symbols"), 200))
    targets: dict[str, dict] = {}

    # Execution state must never be crowded out by a large watch/recommendation
    # set. Pending orders and open positions drive fills, TP/SL, trailing stops,
    # and live protection sync; recommendations only use the remaining capacity.
    if cfg.get("include_open_paper_trades", True):
        for rec in _load_pending_paper_order_recs():
            symbol = str(rec.get("symbol") or "").strip().upper()
            if symbol:
                targets[symbol] = rec
                if len(targets) >= max_symbols:
                    return targets

        for rec in _load_open_paper_trade_recs():
            symbol = str(rec.get("symbol") or "").strip().upper()
            if symbol:
                targets[symbol] = rec
                if len(targets) >= max_symbols:
                    return targets

    if cfg.get("include_actionable_recommendations", True):
        remaining = max(0, max_symbols - len(targets))
        if remaining > 0:
            for rec in get_active_recommendations_deduped(actionable_only=True, limit=remaining, with_meta=False):
                symbol = str(rec.get("symbol") or "").strip().upper()
                if symbol and symbol not in targets:
                    targets[symbol] = dict(rec)
                    if len(targets) >= max_symbols:
                        break

    return targets


def handle_price_tick(symbol: str, price: float, targets: dict[str, dict], event_time: str | None = None, cfg: dict | None = None) -> dict:
    cfg = cfg or price_streamer_config()
    symbol = str(symbol or "").strip().upper()
    price = _safe_float(price)
    if not symbol or price <= 0:
        return {"skipped": True, "reason": "invalid_tick"}
    event_time = event_time or _now()
    if cfg.get("update_latest_price_cache", True):
        update_latest_price_cache(symbol, price, updated_at=event_time, source="price_streamer")
    if not cfg.get("sync_paper_trading", True):
        return {"updated_price": True, "paper_trading": {"skipped": True, "reason": "disabled_by_streamer"}}
    # Pending limit orders are executable state. Prefer the order snapshot over
    # any stale in-memory recommendation target so a websocket tick can fill the
    # order immediately when the price touches.
    rec = _load_pending_paper_order_rec(symbol) or targets.get(symbol)
    if not rec:
        return {"updated_price": True, "paper_trading": {"skipped": True, "reason": "no_target"}}
    result = sync_recommendation(rec, price, event_time=event_time)
    if result.get("trade_id") and (result.get("opened") or result.get("paper_order", {}).get("filled")):
        result["live_sync"] = sync_paper_trade_to_live(int(result["trade_id"]), execute=True)
    if result.get("trade_id") and (
        result.get("closed")
        or result.get("activated")
        or result.get("moved")
        or result.get("tightened")
        or result.get("trailing_stop")
    ):
        result["live_protection_sync"] = sync_live_protection_from_paper(limit=20)
    return {"updated_price": True, "paper_trading": result}


def _parse_ticker_message(raw: str) -> tuple[str, float]:
    payload = json.loads(raw)
    data = payload.get("data") if isinstance(payload, dict) else None
    if not isinstance(data, dict):
        data = payload if isinstance(payload, dict) else {}
    symbol = str(data.get("s") or "")
    price = _safe_float(data.get("c") or data.get("p") or data.get("lastPrice"))
    if symbol.endswith("USDT"):
        symbol = f"{symbol[:-4]}/USDT"
    return symbol.upper(), price


def _is_transient_ws_error(exc: BaseException) -> bool:
    if isinstance(exc, (ConnectionClosed, ConnectionClosedError, ConnectionClosedOK, TimeoutError, asyncio.TimeoutError, OSError)):
        return True
    message = str(exc).lower()
    return any(
        needle in message
        for needle in (
            "keepalive ping timeout",
            "no close frame received",
            "connection closed",
            "connection reset",
            "temporarily unavailable",
            "timed out",
        )
    )


def _record_transient_disconnect(exc: BaseException, cfg: dict, symbols_count: int) -> None:
    global _LAST_TRANSIENT_LOG_AT, _TRANSIENT_DISCONNECT_COUNT
    _TRANSIENT_DISCONNECT_COUNT += 1
    loop_time = 0.0
    try:
        loop_time = asyncio.get_running_loop().time()
    except Exception:
        loop_time = 0.0
    interval = max(0.0, _safe_float(cfg.get("transient_log_interval_seconds"), 900))
    if interval > 0 and _LAST_TRANSIENT_LOG_AT and loop_time and loop_time - _LAST_TRANSIENT_LOG_AT < interval:
        return
    _LAST_TRANSIENT_LOG_AT = loop_time or _LAST_TRANSIENT_LOG_AT
    try:
        record_system_error(
            source="price_streamer",
            level="warning",
            error_type=exc.__class__.__name__,
            message=f"websocket transient disconnect: {exc}",
            status_code=0,
            context={
                "symbols_count": symbols_count,
                "disconnect_count_since_start": _TRANSIENT_DISCONNECT_COUNT,
                "reconnect_delay_seconds": cfg.get("reconnect_delay_seconds"),
            },
            fingerprint="price_streamer_transient_disconnect",
        )
    except Exception:
        pass


async def run_forever() -> None:
    init_db()
    cfg = price_streamer_config()
    if not cfg.get("enabled", True):
        print("[price-streamer] disabled by system_config.price_streamer", flush=True)
        while True:
            await asyncio.sleep(max(1.0, _safe_float(cfg.get("idle_sleep_seconds"), 5)))

    refresh_seconds = max(5.0, _safe_float(cfg.get("refresh_symbols_seconds"), 20))
    idle_sleep = max(1.0, _safe_float(cfg.get("idle_sleep_seconds"), 5))
    reconnect_delay = max(1.0, _safe_float(cfg.get("reconnect_delay_seconds"), 5))
    log_every = max(1, _safe_int(cfg.get("log_every_events"), 100))

    while True:
        symbols_count = 0
        try:
            cfg = price_streamer_config()
            targets = load_stream_targets(cfg=cfg)
            symbols = sorted(targets.keys())
            symbols_count = len(symbols)
            if not symbols:
                print("[price-streamer] no active symbols, sleeping", flush=True)
                await asyncio.sleep(idle_sleep)
                continue
            url = _stream_url(symbols, cfg)
            print(f"[price-streamer] connecting symbols={len(symbols)}", flush=True)
            last_refresh = asyncio.get_running_loop().time()
            count = 0
            async with websockets.connect(
                url,
                ping_interval=max(5.0, _safe_float(cfg.get("ping_interval_seconds"), 30)),
                ping_timeout=max(5.0, _safe_float(cfg.get("ping_timeout_seconds"), 60)),
                close_timeout=max(1.0, _safe_float(cfg.get("close_timeout_seconds"), 5)),
            ) as ws:
                async for raw in ws:
                    symbol, price = _parse_ticker_message(raw)
                    if symbol and price > 0:
                        handle_price_tick(symbol, price, targets, event_time=_now(), cfg=cfg)
                        count += 1
                        if count % log_every == 0:
                            print(f"[price-streamer] ticks={count} latest={symbol} {price}", flush=True)
                    if asyncio.get_running_loop().time() - last_refresh >= refresh_seconds:
                        new_targets = load_stream_targets(cfg=cfg)
                        if sorted(new_targets.keys()) != symbols:
                            print("[price-streamer] symbol set changed, reconnecting", flush=True)
                            break
                        targets = new_targets
                        last_refresh = asyncio.get_running_loop().time()
        except Exception as exc:
            if _is_transient_ws_error(exc):
                print(f"[price-streamer] websocket disconnected, reconnecting: {exc}", flush=True)
                _record_transient_disconnect(exc, cfg, symbols_count)
            else:
                print(f"[price-streamer] error: {exc}", flush=True)
                try:
                    record_exception(exc, source="price_streamer")
                except Exception:
                    pass
            await asyncio.sleep(reconnect_delay)


def main():
    asyncio.run(run_forever())


__all__ = [
    "handle_price_tick",
    "load_stream_targets",
    "main",
    "run_forever",
]


if __name__ == "__main__":
    main()