#!/usr/bin/env python3
# Copyright (c) 2026 Krzysztof Rudnicki. MIT licence.
"""Measure what one text reply costs the bot's own code, against the live bot.

    tool/latency.py testbot                 # 20 x !pomoc, judged at 100 ms p95
    tool/latency.py testbot --text '!ja' --times 50
    tool/latency.py testbot --budget 50

Posts for real into the named group, which must be in SELFTEST_GROUPS -- the
same fail-closed rule as scripts/selftest.sh. The command's cooldown is
switched off for the run and put back afterwards. Exit 1 when the 95th
percentile of the bot's own time is over budget; see signal_bot/latency.py
for what "own" excludes and why.
"""

from __future__ import annotations

import argparse
import asyncio
import os
import sys
from typing import Final

import httpx
from dotenv import load_dotenv

from signal_bot.app import HTTP_TIMEOUT_SECONDS, USER_AGENT
from signal_bot.latency import LatencyError, measure
from signal_bot.served import OWN_BUDGET_MS

EXIT_OVER_BUDGET: Final = 1
EXIT_REFUSED: Final = 2
DEFAULT_TIMES: Final = 20


async def run(group: str, text: str, times: int, budget_ms: int, base: str) -> int:
    """One measured run; the exit code is the verdict."""
    async with httpx.AsyncClient(
        timeout=HTTP_TIMEOUT_SECONDS, headers={"User-Agent": USER_AGENT}
    ) as client:
        report = await measure(client, base, group, text, times, budget_ms)
    sys.stdout.write(report.render() + "\n")
    return 0 if report.within_budget else EXIT_OVER_BUDGET


def main() -> int:
    """Parse arguments and run one measurement."""
    parser = argparse.ArgumentParser(
        description=__doc__, formatter_class=argparse.RawDescriptionHelpFormatter
    )
    parser.add_argument("group", help="test group name; must be in SELFTEST_GROUPS")
    parser.add_argument("--text", default="!pomoc", help="the command to type (default: !pomoc)")
    parser.add_argument("--times", type=int, default=DEFAULT_TIMES, help="replies to sample")
    parser.add_argument("--budget", type=int, default=OWN_BUDGET_MS, help="p95 own_ms allowed")
    args = parser.parse_args()
    load_dotenv()
    base = f"http://127.0.0.1:{os.environ.get('BIND_PORT', '8137')}"
    try:
        return asyncio.run(run(args.group, args.text, args.times, args.budget, base))
    except (LatencyError, httpx.HTTPError) as error:
        sys.stderr.write(f"latency: {error}\n")
        return EXIT_REFUSED


if __name__ == "__main__":
    raise SystemExit(main())