import pytest
from unittest.mock import patch, MagicMock
from openvpncertupdate import send_email


def make_popen(returncode=0):
    proc = MagicMock()
    proc.communicate.return_value = (b"", b"")
    proc.returncode = returncode
    return proc


def test_calls_mail_binary(tmp_path):
    tmpl = tmp_path / "t.txt"; tmpl.write_text("{cn} {url} {config_name}")
    att  = tmp_path / "c.ovpn"; att.write_text("x")
    captured = {}
    def fake_popen(cmd, **kw): captured["cmd"] = cmd; return make_popen()
    with patch("openvpncertupdate.subprocess.Popen", side_effect=fake_popen):
        send_email("to@x.com", "alice", "http://u", str(att),
                   "f@x.com", "Subj", str(tmpl), "msmtp")
    assert captured["cmd"] == ["msmtp", "-t"]


def test_body_contains_cn_and_url(tmp_path):
    tmpl = tmp_path / "t.txt"; tmpl.write_text("Dear {cn}, see {url} for {config_name}")
    att  = tmp_path / "c.ovpn"; att.write_text("")
    received = {}
    def fake_popen(cmd, **kw):
        p = MagicMock()
        p.communicate = lambda input=None: (received.update({"data": input}) or b"", b"")
        p.returncode = 0
        return p
    with patch("openvpncertupdate.subprocess.Popen", side_effect=fake_popen):
        send_email("to@x.com", "bob", "http://secret", str(att),
                   "f@x.com", "s", str(tmpl), "msmtp")
    body = received["data"].decode()
    assert "bob" in body
    assert "http://secret" in body


def test_raises_on_failure(tmp_path):
    tmpl = tmp_path / "t.txt"; tmpl.write_text("{cn} {url} {config_name}")
    att  = tmp_path / "c.ovpn"; att.write_text("")
    with patch("openvpncertupdate.subprocess.Popen", return_value=make_popen(returncode=1)):
        with pytest.raises(RuntimeError, match="mail"):
            send_email("x@y.com", "cn", "url", str(att),
                       "f@x.com", "s", str(tmpl), "msmtp")