import boto3
import urllib3
from botocore.config import Config
from ..config import get_settings

# Suppress SSL warnings for self-signed certificate
urllib3.disable_warnings(urllib3.exceptions.InsecureRequestWarning)

settings = get_settings()


def get_s3_client():
    return boto3.client(
        "s3",
        endpoint_url=settings.s3_endpoint_url,
        aws_access_key_id=settings.s3_access_key,
        aws_secret_access_key=settings.s3_secret_key,
        region_name=settings.s3_region,
        config=Config(signature_version="s3v4"),
        verify=False,  # FirstVDS uses self-signed certificate
    )


async def get_total_storage_size() -> int:
    """Returns total size of all objects in bucket in bytes"""
    client = get_s3_client()
    total_size = 0

    paginator = client.get_paginator("list_objects_v2")
    for page in paginator.paginate(Bucket=settings.s3_bucket_name):
        for obj in page.get("Contents", []):
            total_size += obj["Size"]

    return total_size


async def can_upload_file(file_size: int) -> bool:
    """Check if file can be uploaded without exceeding storage limit"""
    max_bytes = settings.max_storage_gb * 1024 * 1024 * 1024
    current_size = await get_total_storage_size()
    return (current_size + file_size) <= max_bytes


async def upload_file(file_content: bytes, s3_key: str, content_type: str = "audio/mpeg") -> str:
    """Upload file to S3 and return the key"""
    client = get_s3_client()
    client.put_object(
        Bucket=settings.s3_bucket_name,
        Key=s3_key,
        Body=file_content,
        ContentType=content_type,
    )
    return s3_key


async def delete_file(s3_key: str) -> None:
    """Delete file from S3"""
    client = get_s3_client()
    client.delete_object(Bucket=settings.s3_bucket_name, Key=s3_key)


def generate_presigned_url(s3_key: str, expiration: int = 3600) -> str:
    """Generate presigned URL for file access"""
    client = get_s3_client()
    url = client.generate_presigned_url(
        "get_object",
        Params={"Bucket": settings.s3_bucket_name, "Key": s3_key},
        ExpiresIn=expiration,
    )
    return url


def get_file_content(s3_key: str) -> bytes:
    """Get full file content from S3"""
    client = get_s3_client()
    response = client.get_object(Bucket=settings.s3_bucket_name, Key=s3_key)
    return response["Body"].read()


def get_file_size(s3_key: str) -> int:
    """Get file size from S3 without downloading"""
    client = get_s3_client()
    response = client.head_object(Bucket=settings.s3_bucket_name, Key=s3_key)
    return response["ContentLength"]


def get_file_range(s3_key: str, start: int, end: int):
    """Get a range of bytes from S3 file"""
    client = get_s3_client()
    response = client.get_object(
        Bucket=settings.s3_bucket_name,
        Key=s3_key,
        Range=f"bytes={start}-{end}"
    )
    return response["Body"].read()


def stream_file_chunks(s3_key: str, start: int = 0, end: int = None, chunk_size: int = 64 * 1024):
    """Stream file from S3 in chunks (default 64KB chunks)"""
    client = get_s3_client()

    if end is None:
        range_header = f"bytes={start}-"
    else:
        range_header = f"bytes={start}-{end}"

    response = client.get_object(
        Bucket=settings.s3_bucket_name,
        Key=s3_key,
        Range=range_header
    )

    for chunk in response["Body"].iter_chunks(chunk_size=chunk_size):
        yield chunk