"""Kill Switch Impact Analysis: Compare live vs research mode.

How much does the permanent kill switch hide?

Runs the backtest twice (live mode and research mode) and compares
key metrics side-by-side.

Usage:
  python -m apps.tools.kill_switch_impact_analysis \
    --manifest configs/experiments/return_max_long_v1.1.json \
    --snapshot-dir data/datasets/snapshots \
    --split train [--output-root ./runs]
"""
from __future__ import annotations

import argparse
from pathlib import Path

from libs.backtest.manifests import load_manifest, resolve_config
from libs.backtest.domain import MetricsBundle


def _run_backtest(
    manifest_path: str,
    snapshot_dir: str | None,
    split: str,
    mode: str,
    output_root: str,
    initial_equity: float,
    config_root: str,
) -> tuple[str, MetricsBundle, int]:
    """Run a single backtest and return (run_id, metrics, trade_count)."""
    from apps.backtester.run import BacktestRunner, _build_store

    manifest = load_manifest(manifest_path)
    config = resolve_config(manifest, config_root=config_root)
    config.risk.backtest_mode = mode

    store = _build_store(manifest, config, split, snapshot_dir_override=snapshot_dir)
    runner = BacktestRunner(
        manifest=manifest,
        config=config,
        store=store,
        initial_equity=initial_equity,
    )
    result = runner.run(output_root=output_root)
    return result.run_id, result.metrics, result.metrics.trade_count


def _fmt(val: float | None, fmt: str = ".2f") -> str:
    if val is None:
        return "N/A"
    return f"{val:{fmt}}"


def _fmt_pct(val: float | None) -> str:
    if val is None:
        return "N/A"
    return f"{val:.2f}%"


def main() -> None:
    parser = argparse.ArgumentParser(description="Kill Switch Impact Analysis")
    parser.add_argument("--manifest", required=True, help="Path to experiment manifest JSON")
    parser.add_argument("--snapshot-dir", help="Override snapshot root directory")
    parser.add_argument("--split", default="train", help="Split name (train/valid/test)")
    parser.add_argument("--output-root", default="./runs", help="Output root directory")
    parser.add_argument("--initial-equity", type=float, default=100_000.0)
    parser.add_argument("--config-root", default=".", help="Root dir for resolving config paths")
    args = parser.parse_args()

    print("Running LIVE mode backtest...")
    live_id, live_m, live_trades = _run_backtest(
        args.manifest, args.snapshot_dir, args.split, "live",
        args.output_root, args.initial_equity, args.config_root,
    )

    print("Running RESEARCH mode backtest...")
    research_id, research_m, research_trades = _run_backtest(
        args.manifest, args.snapshot_dir, args.split, "research",
        args.output_root, args.initial_equity, args.config_root,
    )

    # Side-by-side comparison
    print(f"\n{'='*60}")
    print(f"Kill Switch Impact Analysis — split={args.split}")
    print(f"{'='*60}")
    print(f"\n{'Metric':<28} {'Live':>14} {'Research':>14}")
    print("-" * 60)

    rows = [
        ("Run ID", live_id[:16], research_id[:16]),
        ("Total Trades", str(live_trades), str(research_trades)),
        ("Win Rate", _fmt_pct(live_m.win_rate and live_m.win_rate * 100),
         _fmt_pct(research_m.win_rate and research_m.win_rate * 100)),
        ("Total Return", _fmt_pct(live_m.total_return_pct),
         _fmt_pct(research_m.total_return_pct)),
        ("Max Drawdown", _fmt_pct(live_m.max_drawdown_pct),
         _fmt_pct(research_m.max_drawdown_pct)),
        ("Sharpe Ratio", _fmt(live_m.sharpe_ratio), _fmt(research_m.sharpe_ratio)),
        ("Sortino Ratio", _fmt(live_m.sortino_ratio), _fmt(research_m.sortino_ratio)),
        ("Profit Factor", _fmt(live_m.profit_factor), _fmt(research_m.profit_factor)),
        ("Expectancy (R)", _fmt(live_m.expectancy_r), _fmt(research_m.expectancy_r)),
        ("Avg Holding Days", _fmt(live_m.avg_holding_days, ".1f"),
         _fmt(research_m.avg_holding_days, ".1f")),
        ("Avg Positions Held", _fmt(live_m.avg_positions_held, ".1f"),
         _fmt(research_m.avg_positions_held, ".1f")),
    ]

    for label, live_val, research_val in rows:
        print(f"{label:<28} {live_val:>14} {research_val:>14}")

    # Delta summary
    if live_m.total_return_pct is not None and research_m.total_return_pct is not None:
        delta_return = research_m.total_return_pct - live_m.total_return_pct
        delta_trades = research_trades - live_trades
        print(f"\n  Delta trades: {delta_trades:+d}")
        print(f"  Delta return: {delta_return:+.2f}%")


if __name__ == "__main__":
    main()