"""
Task Scheduler — real asyncio-based delayed execution
"""
import asyncio, json, datetime, traceback
from typing import Callable

_pending: list = []  # list of {"at": timestamp, "task": coroutine_fn, "desc": str, "chat_id": int}


async def schedule_task(delay_seconds: float, desc: str, coro_fn, *args, **kwargs):
    """Schedule coro_fn(*args, **kwargs) to run after delay_seconds."""
    async def runner():
        await asyncio.sleep(delay_seconds)
        try:
            await coro_fn(*args, **kwargs)
        except Exception as e:
            print(f"[SCHEDULER] Task '{desc}' failed: {e}\n{traceback.format_exc()}")
    task = asyncio.create_task(runner())
    _pending.append({"desc": desc, "at": datetime.datetime.now().timestamp() + delay_seconds, "task": task})
    print(f"[SCHEDULER] Scheduled '{desc}' in {delay_seconds:.0f}s")
    return task


def parse_delay(text: str) -> float | None:
    """Parse '5 minutes', '30 seconds', '1 hour', '2 mins' → seconds."""
    import re
    text = text.lower().strip()
    patterns = [
        (r'(\d+(?:\.\d+)?)\s*(?:hours?|hrs?|h)\b', 3600),
        (r'(\d+(?:\.\d+)?)\s*(?:minutes?|mins?|m)\b', 60),
        (r'(\d+(?:\.\d+)?)\s*(?:seconds?|secs?|s)\b', 1),
    ]
    total = 0
    found = False
    for pat, mult in patterns:
        for m in re.finditer(pat, text):
            total += float(m.group(1)) * mult
            found = True
    return total if found else None