from collections.abc import Generator

import boto3
from botocore.exceptions import ClientError
from flask import Flask

from extensions.storage.base_storage import BaseStorage


class OracleOCIStorage(BaseStorage):
    """Implementation for Oracle OCI storage."""

    def __init__(self, app: Flask):
        super().__init__(app)
        app_config = self.app.config
        self.bucket_name = app_config.get("OCI_BUCKET_NAME")
        self.client = boto3.client(
            "s3",
            aws_secret_access_key=app_config.get("OCI_SECRET_KEY"),
            aws_access_key_id=app_config.get("OCI_ACCESS_KEY"),
            endpoint_url=app_config.get("OCI_ENDPOINT"),
            region_name=app_config.get("OCI_REGION"),
        )

    def save(self, filename, data):
        self.client.put_object(Bucket=self.bucket_name, Key=filename, Body=data)

    def load_once(self, filename: str) -> bytes:
        try:
            data = self.client.get_object(Bucket=self.bucket_name, Key=filename)["Body"].read()
        except ClientError as ex:
            if ex.response["Error"]["Code"] == "NoSuchKey":
                raise FileNotFoundError("File not found")
            else:
                raise
        return data

    def load_stream(self, filename: str) -> Generator:
        def generate(filename: str = filename) -> Generator:
            try:
                response = self.client.get_object(Bucket=self.bucket_name, Key=filename)
                yield from response["Body"].iter_chunks()
            except ClientError as ex:
                if ex.response["Error"]["Code"] == "NoSuchKey":
                    raise FileNotFoundError("File not found")
                else:
                    raise

        return generate()

    def download(self, filename, target_filepath):
        self.client.download_file(self.bucket_name, filename, target_filepath)

    def exists(self, filename):
        try:
            self.client.head_object(Bucket=self.bucket_name, Key=filename)
            return True
        except:
            return False

    def delete(self, filename):
        self.client.delete_object(Bucket=self.bucket_name, Key=filename)