from __future__ import annotations

from aiobotocore.session import get_session


class S3Service:
    def __init__(
        self,
        *,
        bucket: str,
        region: str,
        access_key_id: str | None,
        secret_access_key: str | None,
        public_base_url: str | None,
        endpoint_url: str | None,
        use_reg_ru_website_public_host: bool,
    ):
        self._bucket = bucket
        self._region = region or 'us-east-1'
        self._access_key_id = access_key_id
        self._secret_access_key = secret_access_key
        pb = (public_base_url or '').strip().rstrip('/')
        self._public_base_url = pb if pb else None
        self._endpoint_url = endpoint_url.strip().rstrip('/') if endpoint_url and endpoint_url.strip() else None
        self._use_reg_ru_website_public_host = use_reg_ru_website_public_host

    @staticmethod
    def _url_prefix_variants(prefix: str) -> list[str]:
        p = prefix.rstrip('/') + '/'
        out = [p]
        if p.startswith('https://'):
            out.append('http://' + p[8:])
        elif p.startswith('http://'):
            out.append('https://' + p[7:])
        return out

    def _public_url_prefixes(self) -> list[str]:
        acc: list[str] = []
        pb = self._public_base_url
        if pb:
            acc.extend(self._url_prefix_variants(pb))
        ep = self._endpoint_url
        if ep:
            base = f'{ep.rstrip("/")}/{self._bucket}'
            acc.extend(self._url_prefix_variants(base))
        if ep and self._use_reg_ru_website_public_host and 's3.regru.cloud' in ep.lower():
            wh = f'https://{self._bucket}.website.regru.cloud'
            acc.extend(self._url_prefix_variants(wh))
        if not ep:
            if self._region == 'us-east-1':
                h = f'https://{self._bucket}.s3.amazonaws.com'
            else:
                h = f'https://{self._bucket}.s3.{self._region}.amazonaws.com'
            acc.extend(self._url_prefix_variants(h))
        seen: set[str] = set()
        uniq: list[str] = []
        for x in sorted(acc, key=len, reverse=True):
            if x not in seen:
                seen.add(x)
                uniq.append(x)
        return uniq

    def object_key_from_public_url(self, url: str) -> str | None:
        u = (url or '').strip()
        if not u:
            return None
        for p in self._public_url_prefixes():
            if u.startswith(p):
                k = u[len(p):].split('?', 1)[0].split('#', 1)[0]
                return k if k else None
        return None

    def _object_url(self, key: str) -> str:
        if self._public_base_url:
            return f'{self._public_base_url}/{key}'
        endpoint = self._endpoint_url
        if endpoint:
            if (
                self._use_reg_ru_website_public_host
                and 's3.regru.cloud' in endpoint.lower()
            ):
                return f'https://{self._bucket}.website.regru.cloud/{key}'
            return f'{endpoint}/{self._bucket}/{key}'
        region = self._region
        if region == 'us-east-1':
            host = 's3.amazonaws.com'
        else:
            host = f's3.{region}.amazonaws.com'
        return f'https://{self._bucket}.{host}/{key}'

    async def upload_bytes(self, *, key: str, body: bytes, content_type: str) -> str:
        session = get_session()
        kw: dict[str, object] = {'region_name': self._region}
        aid = self._access_key_id
        sk = self._secret_access_key
        ep = self._endpoint_url
        if aid:
            kw['aws_access_key_id'] = aid
        if sk:
            kw['aws_secret_access_key'] = sk
        if ep:
            kw['endpoint_url'] = ep
        async with session.create_client('s3', **kw) as client:
            await client.put_object(
                Bucket=self._bucket,
                Key=key,
                Body=body,
                ContentType=content_type,
            )
        return self._object_url(key)

    async def delete_object(self, *, key: str) -> None:
        session = get_session()
        kw: dict[str, object] = {'region_name': self._region}
        aid = self._access_key_id
        sk = self._secret_access_key
        ep = self._endpoint_url
        if aid:
            kw['aws_access_key_id'] = aid
        if sk:
            kw['aws_secret_access_key'] = sk
        if ep:
            kw['endpoint_url'] = ep
        async with session.create_client('s3', **kw) as client:
            await client.delete_object(Bucket=self._bucket, Key=key)