import logging
import os
import time
from pathlib import Path

import httpx

from app.config import settings

logger = logging.getLogger(__name__)


def ensure_directories():
    os.makedirs(settings.output_dir, exist_ok=True)
    os.makedirs(settings.temp_dir, exist_ok=True)


async def download_result(task_id: str, url: str) -> str:
    """Download a result file from a URL and store it locally."""
    task_dir = os.path.join(settings.output_dir, task_id)
    os.makedirs(task_dir, exist_ok=True)

    # Derive filename from URL
    filename = url.rsplit('/', 1)[-1].split('?')[0] or 'result'
    if '.' not in filename:
        filename += '.png'

    output_path = os.path.join(task_dir, filename)

    async with httpx.AsyncClient(timeout=120.0) as client:
        response = await client.get(url)
        response.raise_for_status()
        with open(output_path, 'wb') as f:
            f.write(response.content)

    logger.info(f'Downloaded result for {task_id}: {output_path}')
    return output_path


def get_result_path(task_id: str) -> str | None:
    """Get the path to a task's result file."""
    task_dir = os.path.join(settings.output_dir, task_id)
    if not os.path.isdir(task_dir):
        return None
    files = os.listdir(task_dir)
    if not files:
        return None
    return os.path.join(task_dir, files[0])


def cleanup_old_outputs():
    """Remove output directories older than auto_cleanup_hours."""
    cutoff = time.time() - (settings.auto_cleanup_hours * 3600)
    output_dir = Path(settings.output_dir)
    if not output_dir.exists():
        return

    removed = 0
    for task_dir in output_dir.iterdir():
        if task_dir.is_dir() and task_dir.stat().st_mtime < cutoff:
            for f in task_dir.iterdir():
                f.unlink()
            task_dir.rmdir()
            removed += 1

    if removed:
        logger.info(f'Cleaned up {removed} old output directories')