"""
THE LOAD-BEARING TEST for the volatility meta-label pivot.

Question: is 48-72h volatility EXPANSION predictable well enough that a
"block unless P(expansion) >= 0.70" gate is a real filter rather than a
coin flip with extra steps?

This is the one thing worth knowing before any of the pipeline work. If the
answer is no, the architecture is moot regardless of how clean the code is.

Method, deliberately conservative:
  * label  = unsigned 48-72h expansion vs K*ATR, Friday-clipped (vol_target.py)
  * features = volatility-clustering only (no direction, no price level)
  * walk-forward, expanding train window, PURGED by the label span so no
    training row's 72h path overlaps a test row
  * report OOS AUC, and the precision/coverage actually achieved AT the 0.70
    gate -- an AUC alone does not tell you whether the gate is usable

Deliberately NOT done here: any per-symbol threshold tuning, any feature
search. Both would manufacture the result this test exists to check.
"""

from __future__ import annotations

import sys
import numpy as np

sys.path.insert(0, __file__.rsplit("\\", 1)[0] if "\\" in __file__ else ".")

from vol_target import garman_klass_var, expansion_label  # noqa: E402

COMMON = r"C:\Users\admin\AppData\Roaming\MetaQuotes\Terminal\Common\Files"


# ------------------------------------------------------------------ loading
def load(symbol: str, period: str = "PERIOD_H4"):
    path = rf"{COMMON}\bars_{symbol}_{period}.csv"
    raw = np.genfromtxt(path, delimiter=",", skip_header=1, dtype=str, encoding="ansi")
    ts = np.array(
        [f"{r[0][:10].replace('.', '-')}T{r[0][11:]}" for r in raw],
        dtype="datetime64[s]",
    )
    o, h, l, c = (raw[:, i].astype(float) for i in (1, 2, 3, 4))
    v = raw[:, 5].astype(float)
    return ts, o, h, l, c, v


def atr(h, l, c, n=14):
    """Wilder ATR, causal. out[i] uses bars <= i only."""
    tr = np.maximum(h[1:] - l[1:], np.maximum(np.abs(h[1:] - c[:-1]), np.abs(l[1:] - c[:-1])))
    tr = np.concatenate([[h[0] - l[0]], tr])
    out = np.full(len(tr), np.nan)
    if len(tr) <= n:
        return out
    out[n - 1] = tr[:n].mean()
    for i in range(n, len(tr)):
        out[i] = (out[i - 1] * (n - 1) + tr[i]) / n
    return out


def friday_flat(ts_scalar, flat_hour_utc=20):
    """Friday 20:00 UTC (~16:00 NY) liquidation instant for that week."""
    d = ts_scalar.astype("datetime64[D]")
    dow = (d.astype(int) + 4) % 7  # 1970-01-01 was a Thursday -> 0=Mon
    return (d + np.timedelta64(int((4 - dow) % 7), "D")).astype("datetime64[s]") + np.timedelta64(
        flat_hour_utc * 3600, "s"
    )


# ----------------------------------------------------------------- features
def build_features(ts, o, h, l, c, v, a):
    """Volatility-state features ONLY. No direction, no level, no future."""
    gk = garman_klass_var(o, h, l, c)
    gk = np.where(np.isfinite(gk), gk, np.nan)

    def roll_mean(x, n):
        out = np.full(len(x), np.nan)
        cs = np.concatenate([[0.0], np.nancumsum(x)])
        out[n - 1:] = (cs[n:] - cs[:-n]) / n
        return out

    s6, s30, s120 = (np.sqrt(np.maximum(roll_mean(gk, n), 0)) for n in (6, 30, 120))
    rng = (h - l) / np.where(a > 0, a, np.nan)
    rng6 = roll_mean(rng, 6)
    volr = v / np.where(roll_mean(v, 30) > 0, roll_mean(v, 30), np.nan)

    hour = ts.astype("datetime64[h]").astype(int) % 24
    dow = (ts.astype("datetime64[D]").astype(int) + 4) % 7

    feats = {
        "gk_ratio_6_30": s6 / np.where(s30 > 0, s30, np.nan),   # short vs medium vol
        "gk_ratio_30_120": s30 / np.where(s120 > 0, s120, np.nan),
        "gk_level_30": s30,                                      # absolute vol regime
        "range_atr_6": rng6,
        "vol_ratio": volr,
        "hour_sin": np.sin(2 * np.pi * hour / 24),
        "hour_cos": np.cos(2 * np.pi * hour / 24),
        "dow": dow.astype(float),
    }
    names = list(feats)
    X = np.column_stack([feats[k] for k in names])
    return X, names


# ------------------------------------------------------- logistic regression
def fit_logit(X, y, iters=300, lr=0.1, l2=1e-3):
    """Plain gradient descent. No sklearn on this box."""
    Xb = np.column_stack([np.ones(len(X)), X])
    w = np.zeros(Xb.shape[1])
    for _ in range(iters):
        p = 1.0 / (1.0 + np.exp(-np.clip(Xb @ w, -30, 30)))
        g = Xb.T @ (p - y) / len(y) + l2 * np.r_[0.0, w[1:]]
        w -= lr * g
    return w


def predict(w, X):
    Xb = np.column_stack([np.ones(len(X)), X])
    return 1.0 / (1.0 + np.exp(-np.clip(Xb @ w, -30, 30)))


def auc(y, s):
    """Rank AUC with tie handling."""
    y = np.asarray(y)
    if len(np.unique(y)) < 2:
        return np.nan
    order = np.argsort(s)
    r = np.empty(len(s), float)
    sv = np.asarray(s)[order]
    ranks = np.arange(1, len(s) + 1, dtype=float)
    i = 0
    while i < len(sv):
        j = i
        while j + 1 < len(sv) and sv[j + 1] == sv[i]:
            j += 1
        ranks[i:j + 1] = (i + j + 2) / 2.0
        i = j + 1
    r[order] = ranks
    n1 = float((y == 1).sum())
    n0 = float((y == 0).sum())
    return (r[y == 1].sum() - n1 * (n1 + 1) / 2) / (n1 * n0)


# ------------------------------------------------------------------- driver
def run(symbol, k_atr=2.0, n_folds=6, gate=0.70):
    ts, o, h, l, c, v = load(symbol)
    a = atr(h, l, c, 14)
    X, names = build_features(ts, o, h, l, c, v, a)

    trig = np.arange(140, len(ts) - 1)
    y_all, meta = expansion_label(h, l, c, a, ts, trig, k_atr=k_atr,
                                  h_min_hours=48, h_max_hours=72, flat_by=friday_flat)

    keep = (y_all >= 0) & np.isfinite(X[trig]).all(axis=1)
    idx = trig[keep]
    y = y_all[keep].astype(float)
    Xk = X[idx]
    span = int(np.median([m["path_bars"] for m in meta if "path_bars" in m]))

    # standardise on train only, per fold
    n = len(y)
    fold = n // (n_folds + 1)
    rows = []
    for f in range(1, n_folds + 1):
        tr_end = f * fold
        te_beg, te_end = tr_end + span, min(tr_end + span + fold, n)   # PURGE = label span
        if te_end - te_beg < 50:
            continue
        Xtr, ytr = Xk[:tr_end], y[:tr_end]
        Xte, yte = Xk[te_beg:te_end], y[te_beg:te_end]
        mu, sd = Xtr.mean(0), Xtr.std(0)
        sd[sd == 0] = 1.0
        w = fit_logit((Xtr - mu) / sd, ytr)
        p = predict(w, (Xte - mu) / sd)
        sel = p >= gate
        rows.append({
            "fold": f, "n_test": len(yte), "base": yte.mean(),
            "auc": auc(yte, p),
            "cov": sel.mean(),
            "prec": yte[sel].mean() if sel.any() else np.nan,
        })
    return rows, y, span, names


if __name__ == "__main__":
    syms = sys.argv[1:] or ["SP500", "NAS100", "US30", "DAX40", "EURUSD", "USDJPY", "XAUUSD"]
    print(f"{'symbol':<8}{'n':>7}{'base':>8}{'span':>6}{'OOS AUC':>10}{'cov@.70':>9}{'prec@.70':>10}{'lift':>8}")
    print("-" * 66)
    for s in syms:
        try:
            rows, y, span, names = run(s)
        except Exception as e:  # noqa: BLE001
            print(f"{s:<8} FAILED: {e}")
            continue
        if not rows:
            print(f"{s:<8} no usable folds")
            continue
        aucs = np.array([r["auc"] for r in rows], float)
        base = np.average([r["base"] for r in rows], weights=[r["n_test"] for r in rows])
        cov = np.average([r["cov"] for r in rows], weights=[r["n_test"] for r in rows])
        precs = np.array([r["prec"] for r in rows], float)
        wts = np.array([r["cov"] * r["n_test"] for r in rows], float)
        prec = np.nansum(precs * wts) / wts.sum() if wts.sum() > 0 else np.nan
        print(f"{s:<8}{len(y):>7}{base:>8.3f}{span:>6}{np.nanmean(aucs):>10.3f}"
              f"{cov:>9.3f}{prec:>10.3f}{(prec - base):>+8.3f}")