"""Advanced ETH/USDT strategy implementing risk-aware adaptive logic.

This module follows the specification provided in the ETH Strategy
Instruction Set.  It includes configuration constants, persistence,
indicator calculations and a simplified strategy class intended for
usage with Freqtrade or as a stand‑alone loop.  The implementation is
not intended to be production ready but provides a framework that
mirrors the pseudocode specification.
"""

from __future__ import annotations

import json
import math
import os
from dataclasses import dataclass, field, asdict
from datetime import datetime, timedelta, timezone
from typing import Dict, List, Optional, Tuple

import pandas as pd
from pandas import DataFrame
from freqtrade.strategy import IStrategy


# ---------------------------------------------------------------------------
# 1. Configuration constants
# ---------------------------------------------------------------------------


@dataclass(frozen=True)
class Config:
    """Static configuration used across the strategy.

    Values use fraction notation for percentages (e.g. 0.006 == 0.6%).
    """

    exchange_name: str = "kraken"
    pair: str = "ETH/USDT"
    equity_start: float = 8000.0
    exposure_cap_notional_pct: float = 0.30
    target_alloc_pct: float = 0.50
    target_band: float = 0.08
    base_risk_pct: float = 0.006  # 0.60 percent
    max_total_risk_mult: float = 2.0
    max_adds: int = 4
    add_size_decay: float = 0.80
    add_spacing_atr: float = 0.70
    grid_step_min_pct: float = 0.007
    trend_tp_floor_pct: float = 0.011
    range_tp_floor_pct: float = 0.008
    trail_arm_atr: float = 1.00
    trail_dist_trend_atr: float = 0.80
    trail_dist_range_atr: float = 1.10
    no_rebuy_buffer_atr: float = 0.40
    time_exit_days: int = 4
    cooldown_candles_1h: int = 3
    spread_max_bps: int = 15
    slippage_max_bps: int = 10
    unfilled_timeout_sec: int = 90
    fee_buffer_pct: float = 0.001


# ---------------------------------------------------------------------------
# 2. Persistent state handling
# ---------------------------------------------------------------------------


STATE_PATH = os.path.join(os.path.dirname(__file__), "state.json")


@dataclass
class StateStore:
    """Holds state that must persist across restarts."""

    last_regime: Optional[str] = None
    last_exit_price: Optional[float] = None
    last_grid_anchor: Optional[float] = None
    trail_active: bool = False
    trail_anchor_price: Optional[float] = None
    trail_dist_atr: Optional[float] = None
    add_count: int = 0
    last_add_price: Optional[float] = None
    bootstrap_state: str = "PENDING"  # or "DONE"
    daily_loss_realized: float = 0.0
    open_order_intent_hash: Optional[str] = None

    @classmethod
    def load(cls) -> "StateStore":
        if os.path.exists(STATE_PATH):
            with open(STATE_PATH, "r", encoding="utf-8") as fh:
                data = json.load(fh)
            return cls(**data)
        return cls()

    def save(self) -> None:
        with open(STATE_PATH, "w", encoding="utf-8") as fh:
            json.dump(asdict(self), fh, indent=2, sort_keys=True)


# ---------------------------------------------------------------------------
# 3. Data access helpers (placeholders for exchange queries)
# ---------------------------------------------------------------------------


class Data:
    """Container for data loading helpers.

    These functions are placeholders.  A production system would plug in
    real implementations that query the exchange or data provider.
    """

    @staticmethod
    def load_candles(pair: str, timeframe: str) -> pd.DataFrame:
        """Return OHLCV candles for the pair/timeframe.

        The dummy implementation returns an empty DataFrame so that unit
        tests focusing on helper logic can run without network access.
        """

        _ = pair, timeframe
        return pd.DataFrame(columns=["open", "high", "low", "close", "volume", "time"])

    @staticmethod
    def load_orderbook_top(pair: str) -> Tuple[float, float, float]:
        """Return best bid, ask and spread for the pair."""

        _ = pair
        return (0.0, 0.0, 0.0)

    @staticmethod
    def load_exchange_meta(pair: str) -> Dict[str, float]:
        """Return precision, min notional and fees for the pair."""

        _ = pair
        return {
            "price_precision": 2,
            "qty_precision": 6,
            "min_notional": 10.0,
            "fees": 0.0016,
        }

    @staticmethod
    def load_balances() -> Dict[str, float]:
        """Return dummy balances."""

        return {
            "usdt_free": 0.0,
            "eth_free": 0.0,
            "usdt_locked": 0.0,
            "eth_locked": 0.0,
        }

    @staticmethod
    def load_open_orders(pair: str) -> List[Dict]:
        _ = pair
        return []

    @staticmethod
    def server_time() -> datetime:
        return datetime.now(timezone.utc)


# ---------------------------------------------------------------------------
# 4. Indicator calculations
# ---------------------------------------------------------------------------


class Indicators:
    """Indicator calculation helpers using pandas."""

    @staticmethod
    def ema(series: pd.Series, period: int) -> pd.Series:
        return series.ewm(span=period, adjust=False).mean()

    @staticmethod
    def atr(high: pd.Series, low: pd.Series, close: pd.Series, period: int) -> pd.Series:
        high_low = high - low
        high_close = (high - close.shift()).abs()
        low_close = (low - close.shift()).abs()
        ranges = pd.concat([high_low, high_close, low_close], axis=1)
        true_range = ranges.max(axis=1)
        return true_range.rolling(window=period, min_periods=period).mean()

    @staticmethod
    def adx(high: pd.Series, low: pd.Series, close: pd.Series, period: int) -> pd.Series:
        # Simplified ADX implementation.
        plus_dm = high.diff()
        minus_dm = -low.diff()
        plus_dm[plus_dm < 0] = 0
        minus_dm[minus_dm < 0] = 0
        tr = Indicators.atr(high, low, close, period)
        plus_di = 100 * (plus_dm.ewm(alpha=1 / period).mean() / tr)
        minus_di = 100 * (minus_dm.ewm(alpha=1 / period).mean() / tr)
        dx = (abs(plus_di - minus_di) / (plus_di + minus_di)) * 100
        adx = dx.ewm(alpha=1 / period).mean()
        return adx

    @staticmethod
    def vwap(candles: pd.DataFrame) -> float:
        if candles.empty:
            return 0.0
        pv = (candles["close"] * candles["volume"]).cumsum()
        vol = candles["volume"].cumsum()
        return float((pv / vol).iloc[-1])

    @staticmethod
    def anchored_vwap_weekly(candles_1h: pd.DataFrame) -> float:
        if candles_1h.empty:
            return 0.0
        # anchor at start of ISO week
        candles_1h = candles_1h.copy()
        candles_1h["time"] = pd.to_datetime(candles_1h["time"], unit="ms", utc=True)
        start = candles_1h["time"].iloc[-1] - timedelta(days=candles_1h["time"].iloc[-1].weekday())
        week = candles_1h[candles_1h["time"] >= start]
        return Indicators.vwap(week)

    @staticmethod
    def donchian_high(series: pd.Series, period: int) -> pd.Series:
        return series.rolling(window=period, min_periods=period).max()


# ---------------------------------------------------------------------------
# 5. Computation helpers
# ---------------------------------------------------------------------------


class Computations:
    @staticmethod
    def regime(c1: pd.DataFrame) -> str:
        ema200 = Indicators.ema(c1["close"], 200)
        slope = ema200.diff()
        adx14 = Indicators.adx(c1["high"], c1["low"], c1["close"], 14)
        if slope.iloc[-1] > 0 and adx14.iloc[-1] >= 18:
            return "TREND"
        return "RANGE"

    @staticmethod
    def atr_block(c1: pd.DataFrame) -> Tuple[float, float, float]:
        atr14 = Indicators.atr(c1["high"], c1["low"], c1["close"], 14).iloc[-1]
        price = float(c1["close"].iloc[-1]) if not c1.empty else 0.0
        atr_pct = atr14 / price if price else 0.0
        return atr14, atr_pct, price

    @staticmethod
    def unit_risk(atr14: float, price: float) -> float:
        return max(0.8 * atr14, 0.012 * price)

    @staticmethod
    def base_stake(equity: float, unit_risk: float, precision: int = 6) -> float:
        risk_budget = Config.base_risk_pct * equity
        stake_qty = risk_budget / unit_risk if unit_risk else 0.0
        return round(stake_qty, precision)

    @staticmethod
    def exposure_cap_notional(equity: float, price: float) -> float:
        return Config.exposure_cap_notional_pct * equity

    @staticmethod
    def allocation_pct(balances: Dict[str, float], price: float) -> float:
        eth_val = (balances.get("eth_free", 0) + balances.get("eth_locked", 0)) * price
        usdt_val = balances.get("usdt_free", 0) + balances.get("usdt_locked", 0)
        port_val = eth_val + usdt_val
        return eth_val / port_val if port_val else 0.0


# ---------------------------------------------------------------------------
# 6. Guards and protective checks
# ---------------------------------------------------------------------------


class Guards:
    @staticmethod
    def spread_ok(spread_bps: float) -> bool:
        return spread_bps <= Config.spread_max_bps

    @staticmethod
    def slippage_ok(projected_bps: float) -> bool:
        return projected_bps <= Config.slippage_max_bps

    @staticmethod
    def data_fresh(c5: pd.DataFrame, srv_time: datetime) -> bool:
        if c5.empty:
            return False
        last_time = pd.to_datetime(c5["time"].iloc[-1], unit="ms", utc=True)
        return srv_time - last_time <= timedelta(minutes=10)

    @staticmethod
    def daily_loss_ok(state: StateStore, equity: float) -> bool:
        return state.daily_loss_realized <= 0.012 * equity


# ---------------------------------------------------------------------------
# 7. Inventory bootstrap (simplified)
# ---------------------------------------------------------------------------


class InventoryBootstrap:
    @staticmethod
    def desired_inventory_orders(c1: pd.DataFrame, balances: Dict[str, float], price: float, atr14: float) -> List[Dict]:
        alloc = Computations.allocation_pct(balances, price)
        v = Indicators.vwap(c1)
        step = 0.6 * atr14
        orders: List[Dict] = []
        if alloc > Config.target_alloc_pct + Config.target_band:
            level = v + step
            qty = (alloc - (Config.target_alloc_pct + Config.target_band)) * (balances.get("eth_free", 0) + balances.get("eth_locked", 0))
            orders.append({"side": "sell", "price": level, "qty": abs(qty)})
        elif alloc < Config.target_alloc_pct - Config.target_band:
            level = v - step
            usdt_value = (Config.target_alloc_pct - Config.target_band - alloc) * (balances.get("usdt_free", 0) + balances.get("usdt_locked", 0) + price * (balances.get("eth_free", 0) + balances.get("eth_locked", 0)))
            qty = usdt_value / price if price else 0.0
            orders.append({"side": "buy", "price": level, "qty": abs(qty)})
        return orders


# ---------------------------------------------------------------------------
# 8. Entry / Exit signal generation
# ---------------------------------------------------------------------------


class EntryExit:
    @staticmethod
    def entry_signals(c1: pd.DataFrame, c5: pd.DataFrame, regime_value: str) -> Dict[str, bool]:
        atr14, _, _ = Computations.atr_block(c1)
        v = Indicators.vwap(c1)
        aw = Indicators.anchored_vwap_weekly(c1)
        dc_high = Indicators.donchian_high(c1["high"], 20).iloc[-1] if not c1.empty else 0
        signals: Dict[str, bool] = {}
        if regime_value == "TREND":
            last_close = c1["close"].iloc[-1] if not c1.empty else 0
            signals["long_breakout"] = bool(last_close > dc_high or last_close > aw)
        else:
            step = max(0.75 * atr14, Config.grid_step_min_pct * v)
            signals["grid_step"] = step
        return signals

    @staticmethod
    def exit_rules(regime_value: str, atr14: float, entry_price: float, last_exit_price: Optional[float]) -> Tuple[float, float, float, float]:
        if regime_value == "TREND":
            tp_dist = max(1.3 * atr14, Config.trend_tp_floor_pct * entry_price)
            trail_arm = Config.trail_arm_atr * atr14
            trail_dist = Config.trail_dist_trend_atr * atr14
        else:
            tp_dist = max(1.1 * atr14, Config.range_tp_floor_pct * entry_price)
            trail_arm = Config.trail_arm_atr * atr14
            trail_dist = Config.trail_dist_range_atr * atr14
        rebuy_buffer = Config.no_rebuy_buffer_atr * atr14
        return tp_dist, trail_arm, trail_dist, rebuy_buffer


# ---------------------------------------------------------------------------
# 9. Risk sizing helpers
# ---------------------------------------------------------------------------


class RiskSizer:
    @staticmethod
    def compute_stakes(equity: float, unit_risk: float, price: float) -> List[float]:
        base_qty = Computations.base_stake(equity, unit_risk)
        stakes = [base_qty]
        qty = base_qty
        for _ in range(Config.max_adds):
            qty *= Config.add_size_decay
            stakes.append(round(qty, 6))
        cap_notional = Computations.exposure_cap_notional(equity, price)
        # Clip stakes if they exceed exposure cap
        total_notional = 0.0
        clipped: List[float] = []
        for q in stakes:
            notional = q * price
            if total_notional + notional > cap_notional:
                break
            clipped.append(q)
            total_notional += notional
        return clipped


# ---------------------------------------------------------------------------
# 10. Order lifecycle (stubs)
# ---------------------------------------------------------------------------


class OrderLifecycle:
    @staticmethod
    def reconcile_orders(desired_set: List[Dict], open_orders: List[Dict], precision: int, min_notional: float) -> None:
        # Placeholder implementation – in production this would cancel and
        # place orders on the exchange.
        _ = desired_set, open_orders, precision, min_notional

    @staticmethod
    def handle_timeouts(open_orders: List[Dict]) -> None:
        _ = open_orders

    @staticmethod
    def handle_partials(fills: List[Dict], precision: int, min_notional: float) -> None:
        _ = fills, precision, min_notional


# ---------------------------------------------------------------------------
# 11. Freqtrade strategy class
# ---------------------------------------------------------------------------


class EthStrategy(IStrategy):
    """Minimal Freqtrade-compatible strategy using helpers from this module."""

    timeframe = "5m"
    process_only_new_candles = True
    startup_candle_count = 200
    minimal_roi = {"0": 0.02}
    stoploss = -0.10
    trailing_stop = False

    def populate_indicators(self, dataframe: DataFrame, metadata: dict) -> DataFrame:
        dataframe["ema_fast"] = Indicators.ema(dataframe["close"], 12)
        dataframe["ema_slow"] = Indicators.ema(dataframe["close"], 26)
        dataframe["atr14"] = Indicators.atr(dataframe["high"], dataframe["low"], dataframe["close"], 14)
        dataframe["donchian_high"] = Indicators.donchian_high(dataframe["high"], 20)
        return dataframe

    def populate_entry_trend(self, dataframe: DataFrame, metadata: dict) -> DataFrame:
        dataframe.loc[
            (dataframe["ema_fast"] > dataframe["ema_slow"]) &
            (dataframe["close"] > dataframe["donchian_high"]),
            "enter_long",
        ] = 1
        return dataframe

    def populate_exit_trend(self, dataframe: DataFrame, metadata: dict) -> DataFrame:
        dataframe.loc[(dataframe["ema_fast"] < dataframe["ema_slow"]), "exit_long"] = 1
        return dataframe


# ---------------------------------------------------------------------------
# 12. Strategy loop (simplified)
# ---------------------------------------------------------------------------


class Strategy:
    def __init__(self) -> None:
        self.state = StateStore.load()

    def on_tick(self) -> None:
        c5 = Data.load_candles(Config.pair, "5m")
        c1 = Data.load_candles(Config.pair, "1h")
        best_bid, best_ask, spread = Data.load_orderbook_top(Config.pair)
        balances = Data.load_balances()
        open_orders = Data.load_open_orders(Config.pair)
        meta = Data.load_exchange_meta(Config.pair)
        srv_time = Data.server_time()

        if not Guards.data_fresh(c5, srv_time):
            return
        if not Guards.spread_ok(spread * 10000):
            return

        reg = Computations.regime(c1)
        atr14, atr_pct, px = Computations.atr_block(c1)
        u_risk = Computations.unit_risk(atr14, px)
        equity = px * (balances.get("eth_free", 0) + balances.get("eth_locked", 0)) + balances.get("usdt_free", 0) + balances.get("usdt_locked", 0)

        if self.state.bootstrap_state != "DONE":
            desired = InventoryBootstrap.desired_inventory_orders(c1, balances, px, atr14)
            OrderLifecycle.reconcile_orders(desired, open_orders, meta["price_precision"], meta["min_notional"])
            alloc = Computations.allocation_pct(balances, px)
            if Config.target_alloc_pct - Config.target_band <= alloc <= Config.target_alloc_pct + Config.target_band:
                self.state.bootstrap_state = "DONE"
                self.state.save()
            return

        desired: List[Dict] = []
        stakes = RiskSizer.compute_stakes(equity, u_risk, px)
        sig = EntryExit.entry_signals(c1, c5, reg)
        if reg == "TREND" and sig.get("long_breakout"):
            desired.append({"side": "buy", "type": "market", "qty": stakes[0] if stakes else 0})
        elif reg == "RANGE" and "grid_step" in sig:
            # Example of a grid order around VWAP
            anchor = Indicators.vwap(c1)
            step = sig["grid_step"]
            desired.append({"side": "buy", "price": anchor - step, "qty": stakes[0], "post_only": True})
            desired.append({"side": "sell", "price": anchor + step, "qty": stakes[0], "post_only": True})

        OrderLifecycle.reconcile_orders(desired, open_orders, meta["price_precision"], meta["min_notional"])
        OrderLifecycle.handle_timeouts(open_orders)
        self.state.save()


if __name__ == "__main__":
    strat = Strategy()
    strat.on_tick()