"""
Storage client for the storage-service HTTP API.

All persistent file I/O goes through storage-service:8020.
The bucket for all document PDFs is 'documents'.
Keys follow the pattern:
  uploaded:  {user_id}/{doc_id}.pdf
  watch-ingested:  watch/{doc_id}.pdf
"""
import logging

import httpx

from app.core.config import settings

logger = logging.getLogger(__name__)

_BUCKET = "documents"


def _storage_url(key: str) -> str:
    return f"{settings.STORAGE_SERVICE_URL}/objects/{_BUCKET}/{key}"


def build_storage_key(user_id: str, doc_id: str) -> str:
    """Return the canonical storage key for a document."""
    return f"{user_id}/{doc_id}.pdf"


async def save_upload(file_data: bytes, user_id: str, doc_id: str) -> str:
    """Upload bytes to storage-service. Returns the storage key."""
    key = build_storage_key(user_id, doc_id)
    async with httpx.AsyncClient(timeout=30.0) as client:
        resp = await client.put(
            _storage_url(key),
            content=file_data,
            headers={"Content-Type": "application/octet-stream"},
        )
        resp.raise_for_status()
    return key


async def download_file(storage_key: str) -> bytes:
    """Download bytes from storage-service by storage key."""
    async with httpx.AsyncClient(timeout=60.0) as client:
        resp = await client.get(_storage_url(storage_key))
        if resp.status_code == 404:
            raise FileNotFoundError(f"Object not found: {storage_key}")
        resp.raise_for_status()
        return resp.content


async def delete_file(storage_key: str) -> None:
    """Delete an object from storage-service. Swallows errors — deletion failure must not 500."""
    try:
        async with httpx.AsyncClient(timeout=10.0) as client:
            resp = await client.delete(_storage_url(storage_key))
            if resp.status_code not in (204, 404):
                logger.warning("storage-service DELETE returned %s for key %s", resp.status_code, storage_key)
    except Exception as exc:
        logger.warning("Could not delete %s from storage-service: %s", storage_key, exc)