"""A/B the Tiingo backfill's effect on registered replays.

Runs the requested strategies through backtest_runner on the current
production store, then again with the pre-backfill snapshot (data/us*.csv
.bak-tiingo) swapped in, and prints CAGR / Sharpe / MaxDD deltas. Files are
swapped under the data_manager panel lock and restored afterwards.

    PYTHONPATH=. uv run python -m research.prod_impact [STRATEGY ...]
"""
from __future__ import annotations

import os
import shutil
import sys

import metrics
import backtest_runner as br
import data_manager

FILES = ["us.csv", "us_open.csv", "us_high.csv", "us_low.csv", "us_volume.csv"]
START = "2018-01-01"


def run(names: list[str]) -> dict:
    r = br.run_market("us", names, None, 10_000.0, 0.001, 2.0, refresh=False, start=START)
    out = {}
    for s in r["strategy_runs"]:
        eq = s["equity"]
        out[s["name"]] = {
            "cagr": metrics.annualized_return(eq),
            "sharpe": metrics.sharpe_ratio(eq.pct_change().dropna()),
            "mdd": metrics.max_drawdown(eq),
        }
    return out


def swap(pre_backfill: bool) -> None:
    """Swap the .bak-tiingo snapshot in or out (live files preserved as .merged-tmp)."""
    for f in FILES:
        live = os.path.join("data", f)
        bak = live + ".bak-tiingo"
        tmp = live + ".merged-tmp"
        if not os.path.exists(bak) and not os.path.exists(tmp):
            continue
        if pre_backfill:
            if os.path.exists(bak):
                shutil.copy2(live, tmp)
                shutil.copy2(bak, live)
        else:
            if os.path.exists(tmp):
                shutil.copy2(tmp, live)
                os.remove(tmp)


def main() -> None:
    names = sys.argv[1:] or ["overnight_recovery_top10", "lowrisk_top20"]
    with data_manager._panel_lock("us"):
        print("=== merged (Tiingo backfill) ===")
        a = run(names)
        swap(pre_backfill=True)
    try:
        print("=== pre-backfill snapshot ===")
        b = run(names)
    finally:
        with data_manager._panel_lock("us"):
            swap(pre_backfill=False)
    print("\nstrategy                              cagr%          sharpe        mdd%")
    for n in a:
        print(f"{n:34s} {a[n]['cagr']*100:6.1f}->{b[n]['cagr']*100:6.1f}  "
              f"{a[n]['sharpe']:5.2f}->{b[n]['sharpe']:5.2f}  "
              f"{a[n]['mdd']*100:6.1f}->{b[n]['mdd']*100:6.1f}")


if __name__ == "__main__":
    main()