import json
import shutil
import subprocess
from dataclasses import asdict
from typing import Callable

from okx_codex_trader.models import Candle, TradeSignal
from okx_codex_trader.strategy import validate_signal


def analyze_with_codex(
    candles: list[Candle],
    symbol: str,
    bar: str,
    runner: Callable[..., subprocess.CompletedProcess[str]] = subprocess.run,
    which: Callable[[str], str | None] = shutil.which,
) -> TradeSignal:
    if which("codex") is None:
        raise FileNotFoundError("codex executable was not found on PATH")

    prompt = (
        "Analyze these market candles and return exactly one JSON object.\n"
        'Do not output markdown, prose, or code fences.\n'
        'The JSON keys must be exactly: "action", "confidence", "leverage", '
        '"entry_price", "take_profit_price", "stop_loss_price", "reason".\n'
        'Valid actions are "long", "short", and "flat".\n'
        "Confidence must be a number from 0 to 1.\n"
        "Leverage must be an integer from 1 to 3.\n"
        "Price fields must be numbers or null.\n"
        f"symbol: {symbol}\n"
        f"bar: {bar}\n"
        f"candles: {json.dumps([asdict(candle) for candle in candles], separators=(',', ':'))}"
    )
    completed = runner(["codex", "exec", prompt], capture_output=True, text=True, check=False)
    if completed.returncode != 0:
        raise ValueError("codex execution failed")

    try:
        payload = json.loads(completed.stdout)
    except json.JSONDecodeError as exc:
        raise ValueError("codex output is not valid JSON") from exc

    if not isinstance(payload, dict):
        raise ValueError("codex output is not valid JSON")

    return validate_signal(payload)