import aiosmtplib
from email.message import EmailMessage
from email.mime.image import MIMEImage
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText
from email.policy import SMTP

from src.application.contracts.i_sender import ISender


class EmailSender(ISender):

    def __init__(
        self,
        host: str,
        port: int,
        username: str,
        password: str,
        from_addr: str,
        use_tls: bool = True,
        timeout: int = 10,
    ):
        self._host = host
        self._port = port
        self._username = username
        self._password = password
        self._from_addr = from_addr
        self._use_tls = use_tls
        self._timeout = timeout

    async def send(
        self,
        to: str,
        subject: str,
        body: str,
        plain: str | None = None,
        *,
        inline_png: tuple[str, bytes] | None = None,
    ) -> None:
        if inline_png and plain:
            message = self._multipart_with_inline_png(
                to=to,
                subject=subject,
                plain=plain,
                html=body,
                content_id=inline_png[0],
                png_bytes=inline_png[1],
            )
        else:
            message = EmailMessage()
            message['From'] = self._from_addr
            message['To'] = to
            message['Subject'] = subject
            if plain:
                message.set_content(plain)
                message.add_alternative(body, subtype='html')
            else:
                message.set_content(body, subtype='html')

        await aiosmtplib.send(
            message,
            hostname=self._host,
            port=self._port,
            username=self._username,
            password=self._password,
            use_tls=self._use_tls,
            timeout=self._timeout,
        )

    def _multipart_with_inline_png(
        self,
        *,
        to: str,
        subject: str,
        plain: str,
        html: str,
        content_id: str,
        png_bytes: bytes,
    ) -> MIMEMultipart:
        root = MIMEMultipart('alternative', policy=SMTP)
        root['Subject'] = subject
        root['From'] = self._from_addr
        root['To'] = to

        root.attach(MIMEText(plain, 'plain', 'utf-8'))

        related = MIMEMultipart('related', policy=SMTP)
        related.attach(MIMEText(html, 'html', 'utf-8'))

        image = MIMEImage(png_bytes, _subtype='png', policy=SMTP)
        image.add_header('Content-ID', f'<{content_id}>')
        image.add_header('Content-Disposition', 'inline', filename='exa-logo.png')
        related.attach(image)

        root.attach(related)
        return root