from __future__ import annotations

import json
from datetime import datetime, timezone
from typing import Any, Optional, Protocol

from .contracts import KernelTransition, TradeSlot
from .control import KernelControlSnapshot
from .journal import _transition_row
from .projection import build_position_state_row
from .utils import json_safe


# ── Fire-and-forget Hz write helpers ─────────────────────────────────────────

def _hz_write_no_wait(hz_map: Any, key: str, value: str) -> None:
    """Submit Hz write to the client's internal thread pool. Never blocks.

    .put() without .blocking() returns a hazelcast Future immediately.
    The Future is intentionally discarded — the network write is already
    queued in the Hz client's thread pool and is not cancelled by GC.
    Hz writes are observability-only; any failure must never affect trading.
    """
    try:
        hz_map.put(key, value)
    except Exception:
        pass


def _json_encode(payload: dict) -> str:
    return json.dumps(payload, separators=(",", ":"), ensure_ascii=False, default=str)


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


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


class HazelcastClientLike(Protocol):
    def get_map(self, name: str): ...
    def get_topic(self, name: str): ...


class HazelcastProjector:
    """Durable BLUE/PINK-compatible projection mirror."""

    def __init__(
        self,
        client: HazelcastClientLike | None = None,
        *,
        active_slots_map: str = "dita_active_slots",
        events_topic: str = "dita_trade_events",
    ) -> None:
        self.client = client
        self.active_slots_map = active_slots_map
        self.events_topic = events_topic

    def publish_slot(self, slot: TradeSlot) -> None:
        if self.client is None:
            return
        self.client.get_map(self.active_slots_map).put(slot.trade_id, build_position_state_row(slot))

    def publish_event(self, event_type: str, payload: dict[str, Any]) -> None:
        if self.client is None:
            return
        topic = self.client.get_topic(self.events_topic)
        topic.publish(
            json.dumps(
                {"event_type": event_type, "payload": json_safe(payload)},
                ensure_ascii=False,
                sort_keys=True,
                default=str,
            )
        )


class HazelcastRowWriter:
    """Callback bridge for ``HazelcastProjection`` writer hooks."""

    def __init__(self, client: HazelcastClientLike) -> None:
        self.client = client

    def __call__(self, name: str, row: dict[str, Any]) -> None:
        if name.endswith("trade_events"):
            self.client.get_topic(name).publish(
                json.dumps(row, ensure_ascii=False, sort_keys=True, default=str)
            )
            return
        if name.endswith("control"):
            key = "control"
        else:
            key = str(row.get("trade_id", row.get("slot_id", row.get("event_id", ""))))
        self.client.get_map(name).put(key, json_safe(row))


# ── PINK DITAv2 non-blocking Hz state writer ──────────────────────────────────

class PinkHzStateWriter:
    """Non-blocking Hz writer for PINK DITAv2 kernel state.

    Dedicated Hz client (separate from the data-feed read client).
    All writes are fire-and-forget: .put() returns a Future that is intentionally
    discarded. A failed write = missed TUI update only — never affects trading.

    BLUE-compatible schema (same shape as DOLPHIN_STATE_BLUE) written to
    DOLPHIN_STATE_PINK / DOLPHIN_PNL_PINK — no overlap with BLUE maps.
    """

    def __init__(
        self,
        cluster: str,
        host: str,
        state_map_name: str,
        pnl_map_name: str,
    ) -> None:
        import hazelcast
        self._client = hazelcast.HazelcastClient(
            cluster_name=cluster,
            cluster_members=[host],
        )
        # Non-blocking proxies (.put() returns Future, does NOT block)
        self._state_map = self._client.get_map(state_map_name)
        self._pnl_map = self._client.get_map(pnl_map_name)

    def write_engine_snapshot(
        self,
        slot_dict: dict,
        acc_dict: dict,
        posture: str = "APEX",
        our_leverage: float = 0.0,
    ) -> None:
        """Write full engine state. Called after every kernel mutation (non-blocking)."""
        payload: dict[str, Any] = {
            "strategy":          "pink",
            "capital":           acc_dict.get("capital", 0.0),
            "equity":            acc_dict.get("equity", 0.0),
            "available_capital": acc_dict.get("available_capital", 0.0),
            "pnl":               acc_dict.get("realized_pnl_total", 0.0),
            "fee_total":         acc_dict.get("fee_total", 0.0),
            "open_positions":    int(acc_dict.get("open_positions", 0)),
            "trade_seq":         int(acc_dict.get("trade_seq", 0)),
            "posture":           posture,
            "capital_frozen":    bool(acc_dict.get("capital_frozen", False)),
            "our_leverage":      our_leverage,
            "slot":              slot_dict,
            "updated_at":        _utcnow_iso(),
        }
        _hz_write_no_wait(self._state_map, "engine_snapshot", _json_encode(payload))
        # Compact "latest" key — same shape as BLUE's DOLPHIN_STATE_BLUE["latest"]
        _hz_write_no_wait(self._state_map, "latest", _json_encode({
            "strategy":  "pink",
            "capital":   payload["capital"],
            "date":      _today_iso(),
            "pnl":       payload["pnl"],
            "trades":    payload["trade_seq"],
            "posture":   posture,
            "updated_at": payload["updated_at"],
        }))

    def write_daily_pnl(self, acc_dict: dict, posture: str = "APEX") -> None:
        """Write per-date PnL row. Called on trade close only."""
        _hz_write_no_wait(self._pnl_map, _today_iso(), _json_encode({
            "pnl":     acc_dict.get("realized_pnl_total", 0.0),
            "capital": acc_dict.get("capital", 0.0),
            "trades":  int(acc_dict.get("trade_seq", 0)),
            "posture": posture,
        }))

    def close(self) -> None:
        try:
            self._client.shutdown()
        except Exception:
            pass