import boto3
from botocore.exceptions import ClientError
from app.core.config import settings

class StorageClient:
    def __init__(self):
        self.s3_client = boto3.client(
            "s3",
            endpoint_url=f"http://{settings.MINIO_ENDPOINT}",
            aws_access_key_id=settings.MINIO_ACCESS_KEY,
            aws_secret_access_key=settings.MINIO_SECRET_KEY,
            config=boto3.session.Config(signature_version='s3v4')
        )
        self.bucket_name = settings.MINIO_BUCKET
        self._ensure_bucket_exists()

    def _ensure_bucket_exists(self):
        try:
            self.s3_client.head_bucket(Bucket=self.bucket_name)
        except ClientError:
            try:
                self.s3_client.create_bucket(Bucket=self.bucket_name)
                # Set bucket policy to public read if needed, or rely on presigned URLs
                # For now, we will rely on presigned URLs for security
            except ClientError as e:
                print(f"Could not create bucket {self.bucket_name}: {e}")

    def upload_file(self, file_obj, object_name: str, content_type: str = None) -> bool:
        try:
            extra_args = {}
            if content_type:
                extra_args["ContentType"] = content_type
            
            self.s3_client.upload_fileobj(file_obj, self.bucket_name, object_name, ExtraArgs=extra_args)
            return True
        except ClientError as e:
            print(f"Error uploading file: {e}")
            return False

    def get_presigned_url(self, object_name: str, expiration=3600) -> str:
        try:
            # We need to replace the internal minio hostname with localhost for the browser
            # if we are accessing it from the host machine/browser.
            # But the backend sees "minio".
            # This is tricky in docker-compose.
            # The client needs a URL that resolves.
            # Usually we use a proxy or just configure the endpoint on the frontend.
            # For now generate the URL and we might need to swap the host in the frontend or 
            # ensure the backend generates a URL accessible to the user.
            
            # Actually, standard practice: Backend generates URL using its known endpoint.
            # If that endpoint is "minio:9000", the browser can't resolve it.
            # So we might need to override the endpoint for presigning.
            
            url = self.s3_client.generate_presigned_url(
                'get_object',
                Params={'Bucket': self.bucket_name, 'Key': object_name},
                ExpiresIn=expiration
            )
            # Hack for localhost dev: replace minio:9000 with localhost:9000
            # dependent on where the request comes from. 
            # Ideally getting this from config would be better.
            return url.replace("http://minio:9000", "http://localhost:9000")
            
        except ClientError as e:
            print(f"Error generating presigned URL: {e}")
            return ""

storage = StorageClient()