import io
import wave

import boto3
from botocore.exceptions import ClientError

from .config import settings


def get_s3_client():
    return boto3.client(
        "s3",
        endpoint_url=settings.storage_endpoint_url,
        aws_access_key_id=settings.storage_access_key,
        aws_secret_access_key=settings.storage_secret_key,
    )


def ensure_bucket_exists() -> None:
    client = get_s3_client()
    try:
        client.head_bucket(Bucket=settings.storage_bucket)
    except ClientError as e:
        if e.response["Error"]["Code"] in ("404", "NoSuchBucket"):
            client.create_bucket(Bucket=settings.storage_bucket)
        else:
            raise


def pcm_to_wav(pcm_data: bytes, sample_rate: int = 24000) -> bytes:
    """Wrap raw 16-bit mono PCM data in a WAV container."""
    buf = io.BytesIO()
    with wave.open(buf, "wb") as wf:
        wf.setnchannels(1)
        wf.setsampwidth(2)  # 16-bit
        wf.setframerate(sample_rate)
        wf.writeframes(pcm_data)
    return buf.getvalue()


def upload_audio(object_key: str, audio_bytes: bytes, content_type: str = "audio/wav") -> None:
    client = get_s3_client()
    client.put_object(
        Bucket=settings.storage_bucket,
        Key=object_key,
        Body=audio_bytes,
        ContentType=content_type,
    )


def download_audio(object_key: str) -> tuple[bytes, str]:
    """Return (file_bytes, content_type)."""
    client = get_s3_client()
    response = client.get_object(Bucket=settings.storage_bucket, Key=object_key)
    content_type = response.get("ContentType", "audio/wav")
    return response["Body"].read(), content_type