import logging
import os
import shutil
import uuid
from typing import List, Tuple

from fastapi import UploadFile

from app.config import settings

logger = logging.getLogger(__name__)


def ensure_directories() -> None:
    for path in (settings.upload_dir, settings.output_dir, settings.models_dir,
                 settings.temp_dir, settings.jobs_dir):
        os.makedirs(path, exist_ok=True)


def create_request_dir() -> str:
    request_id = str(uuid.uuid4())
    request_dir = os.path.join(settings.upload_dir, request_id)
    os.makedirs(request_dir, exist_ok=True)
    return request_dir


async def save_upload(file: UploadFile, directory: str) -> str:
    ext = os.path.splitext(file.filename or '')[1] or ''
    filename = f'{uuid.uuid4()}{ext}'
    filepath = os.path.join(directory, filename)

    with open(filepath, 'wb') as f:
        while chunk := await file.read(1024 * 1024):
            f.write(chunk)

    return filepath


async def save_uploads(files: List[UploadFile], directory: str) -> List[str]:
    paths = []
    for file in files:
        path = await save_upload(file, directory)
        paths.append(path)
    return paths


def generate_output_path(target_path: str) -> str:
    ext = os.path.splitext(target_path)[1] or '.png'
    filename = f'{uuid.uuid4()}{ext}'
    return os.path.join(settings.output_dir, filename)


def cleanup_directory(directory: str) -> None:
    if os.path.isdir(directory):
        shutil.rmtree(directory, ignore_errors=True)


def cleanup_file(filepath: str) -> None:
    if os.path.isfile(filepath):
        os.remove(filepath)


def list_model_files() -> List[Tuple[str, str, int]]:
    """Return list of (name, path, size_bytes) for all .onnx files in models dir."""
    models = []
    models_dir = settings.models_dir
    if not os.path.isdir(models_dir):
        return models

    for name in sorted(os.listdir(models_dir)):
        if name.endswith('.onnx'):
            path = os.path.join(models_dir, name)
            size = os.path.getsize(path)
            models.append((name, path, size))
    return models