import asyncio
from email.message import EmailMessage
from typing import Any

import pytest

from app.adapters.email import SMTPEmailSender, SMTPEmailSenderError


class StubSend:
    def __init__(self, raise_exc: Exception | None = None) -> None:
        self.raise_exc = raise_exc
        self.calls: list[dict[str, Any]] = []

    async def __call__(
        self,
        message: EmailMessage,
        *,
        hostname: str,
        port: int,
        username: str | None,
        password: str | None,
        use_tls: bool,
        start_tls: bool,
        timeout: float,
    ) -> object:
        self.calls.append(
            {
                "message": message,
                "hostname": hostname,
                "port": port,
                "username": username,
                "password": password,
                "use_tls": use_tls,
                "start_tls": start_tls,
                "timeout": timeout,
            }
        )
        if self.raise_exc is not None:
            raise self.raise_exc
        return None


def _make_sender(send: StubSend, **overrides: Any) -> SMTPEmailSender:
    kwargs: dict[str, Any] = {
        "smtp_host": "smtp.test",
        "smtp_port": 587,
        "username": "user",
        "password": "pass",
        "from_address": "no-reply@test",
        "use_tls": True,
        "timeout_seconds": 5.0,
        "send": send,
    }
    kwargs.update(overrides)
    return SMTPEmailSender(**kwargs)


def test_send_email_builds_multipart_message_with_pdf_attachment() -> None:
    send = StubSend()
    sender = _make_sender(send)

    asyncio.run(
        sender.send_email(
            to="client@example.com",
            subject="Накладная по заказу o-1",
            body="hello",
            attachment_bytes=b"%PDF",
            attachment_filename="waybill_o-1.pdf",
        )
    )

    assert len(send.calls) == 1
    call = send.calls[0]
    assert call["hostname"] == "smtp.test"
    assert call["port"] == 587
    assert call["username"] == "user"
    assert call["password"] == "pass"
    assert call["use_tls"] is False
    assert call["start_tls"] is True
    assert call["timeout"] == 5.0

    message: EmailMessage = call["message"]
    assert message["From"] == "no-reply@test"
    assert message["To"] == "client@example.com"
    assert message["Subject"] == "Накладная по заказу o-1"

    parts = list(message.iter_attachments())
    assert len(parts) == 1
    attachment = parts[0]
    assert attachment.get_content_type() == "application/pdf"
    assert attachment.get_filename() == "waybill_o-1.pdf"
    assert attachment.get_payload(decode=True) == b"%PDF"


def test_send_email_uses_tls_for_port_465() -> None:
    send = StubSend()
    sender = _make_sender(send, smtp_port=465)

    asyncio.run(
        sender.send_email(
            to="x@example.com",
            subject="s",
            body="b",
            attachment_bytes=b"",
            attachment_filename="f.pdf",
        )
    )

    call = send.calls[0]
    assert call["use_tls"] is True
    assert call["start_tls"] is False


def test_send_email_disables_tls_when_use_tls_false() -> None:
    send = StubSend()
    sender = _make_sender(send, use_tls=False)

    asyncio.run(
        sender.send_email(
            to="x@example.com",
            subject="s",
            body="b",
            attachment_bytes=b"",
            attachment_filename="f.pdf",
        )
    )

    call = send.calls[0]
    assert call["use_tls"] is False
    assert call["start_tls"] is False


def test_send_email_wraps_send_errors_in_sender_error() -> None:
    send = StubSend(raise_exc=RuntimeError("connection refused"))
    sender = _make_sender(send)

    with pytest.raises(SMTPEmailSenderError, match="connection refused"):
        asyncio.run(
            sender.send_email(
                to="x@example.com",
                subject="s",
                body="b",
                attachment_bytes=b"",
                attachment_filename="f.pdf",
            )
        )


def test_send_email_passes_none_when_credentials_blank() -> None:
    send = StubSend()
    sender = _make_sender(send, username="", password="")

    asyncio.run(
        sender.send_email(
            to="x@example.com",
            subject="s",
            body="b",
            attachment_bytes=b"",
            attachment_filename="f.pdf",
        )
    )

    call = send.calls[0]
    assert call["username"] is None
    assert call["password"] is None


def test_send_email_without_attachment_builds_plain_text_message() -> None:
    send = StubSend()
    sender = _make_sender(send)

    asyncio.run(
        sender.send_email(
            to="client@example.com",
            subject="Оплата принята",
            body="Ваша оплата принята.",
        )
    )

    assert len(send.calls) == 1
    message: EmailMessage = send.calls[0]["message"]
    assert message["From"] == "no-reply@test"
    assert message["To"] == "client@example.com"
    assert message["Subject"] == "Оплата принята"
    assert "Ваша оплата принята." in message.get_content()
    assert list(message.iter_attachments()) == []