from __future__ import annotations

from dataclasses import dataclass
from email.message import EmailMessage
from pathlib import Path

import aiosmtplib


@dataclass
class MailSendResult:
    ok: bool
    error: str | None


class MailNotifier:
    def __init__(
        self,
        smtp_host: str,
        smtp_port: int,
        username: str,
        password: str,
        from_addr: str,
        to_addr: str,
        use_starttls: bool = True,
        use_tls: bool = False,
        timeout_seconds: float = 15,
    ) -> None:
        self.smtp_host = smtp_host
        self.smtp_port = smtp_port
        self.username = username
        self.password = password
        self.from_addr = from_addr
        self.to_addr = to_addr
        self.use_starttls = use_starttls
        self.use_tls = use_tls
        self.timeout_seconds = timeout_seconds

    async def send_message(
        self,
        subject: str,
        body: str,
        attachments: list[str] | None = None,
    ) -> MailSendResult:
        message = EmailMessage()
        message["From"] = self.from_addr
        message["To"] = self.to_addr
        message["Subject"] = subject
        message.set_content(body)

        for attachment in attachments or []:
            path = Path(attachment)
            if not path.exists() or not path.is_file():
                continue

            data = path.read_bytes()
            message.add_attachment(
                data,
                maintype="image",
                subtype="png",
                filename=path.name,
            )

        try:
            await aiosmtplib.send(
                message,
                hostname=self.smtp_host,
                port=self.smtp_port,
                username=self.username,
                password=self.password,
                start_tls=self.use_starttls,
                use_tls=self.use_tls,
                timeout=self.timeout_seconds,
            )
            return MailSendResult(ok=True, error=None)
        except Exception as exc:
            return MailSendResult(ok=False, error=str(exc))