"""The deploy-target tester that dispatches on ``kind``.

``DeployTargetTester`` is one contract with two very different implementations,
and the wizard does not care which one it is talking to: it hands over a
:class:`DeployTargetSpec` and wants a yes/no and a plain-language reason.

The dispatcher exists so the wizard never has to know that `ssh` and `sftp` are
the same protocol while `ftp` is a different world with no host key, no atomic
switch and a mandatory backup. The *differences* are documented on the deployers
themselves; the caller sees one shape.
"""

from __future__ import annotations

from app.application.ports.deploy_target import (
    DEPLOY_KINDS,
    DeployCheck,
    DeployTargetSpec,
)
from app.core.config import settings
from app.core.errors import ValidationError
from app.infrastructure.adapters.deploy_ftp import FtpDeployer
from app.infrastructure.adapters.deploy_ssh import SshDeployer


class DispatchingDeployTargetTester:
    """``test_connection`` routed to the right transport for ``spec.kind``."""

    def __init__(
        self,
        *,
        ssh: SshDeployer | None = None,
        ftp: FtpDeployer | None = None,
    ) -> None:
        allow_private = settings.deploy_allow_private_hosts
        self.ssh = ssh or SshDeployer(allow_private_hosts=allow_private)
        self.ftp = ftp or FtpDeployer(allow_private_hosts=allow_private)

    async def test_connection(self, *, target: DeployTargetSpec) -> DeployCheck:
        if target.kind not in DEPLOY_KINDS:
            raise ValidationError(
                "نوع مقصد استقرار پشتیبانی نمی‌شود؛ مقادیر مجاز: "
                + "، ".join(DEPLOY_KINDS)
            )
        if not target.remote_path.strip():
            raise ValidationError("مسیر مقصد روی سرور مشخص نشده است.")
        if target.kind in ("ssh", "sftp"):
            return await self.ssh.test_connection(target=target)
        return await self.ftp.test_connection(target=target)

    def deployer_for(self, kind: str):
        """The object that can actually deploy to this kind of target."""
        return self.ssh if kind in ("ssh", "sftp") else self.ftp


__all__ = ["DispatchingDeployTargetTester"]