"""Tests for config_service functions."""

from __future__ import annotations

from typing import Any
from unittest.mock import AsyncMock, patch

import pytest

from app.models.config import (
    GlobalConfigUpdate,
    JailConfigListResponse,
    JailConfigResponse,
    LogPreviewRequest,
    RegexTestRequest,
)
from app.services import config_service
from app.services.config_service import (
    ConfigValidationError,
    JailNotFoundError,
)

# ---------------------------------------------------------------------------
# Helpers
# ---------------------------------------------------------------------------

_SOCKET = "/fake/fail2ban.sock"


def _make_global_status(names: str = "sshd") -> tuple[int, list[Any]]:
    return (0, [("Number of jail", 1), ("Jail list", names)])


def _make_short_status() -> tuple[int, list[Any]]:
    return (
        0,
        [
            ("Filter", [("Currently failed", 3), ("Total failed", 20)]),
            ("Actions", [("Currently banned", 2), ("Total banned", 10)]),
        ],
    )


def _make_send(responses: dict[str, Any]) -> AsyncMock:
    async def _side_effect(command: list[Any]) -> Any:
        key = "|".join(str(c) for c in command)
        if key in responses:
            return responses[key]
        for resp_key, resp_value in responses.items():
            if key.startswith(resp_key):
                return resp_value
        return (0, None)

    return AsyncMock(side_effect=_side_effect)


def _patch_client(responses: dict[str, Any]) -> Any:
    mock_send = _make_send(responses)

    class _FakeClient:
        def __init__(self, **_kw: Any) -> None:
            self.send = mock_send

    return patch("app.services.config_service.Fail2BanClient", _FakeClient)


_DEFAULT_JAIL_RESPONSES: dict[str, Any] = {
    "status|sshd|short": _make_short_status(),
    "get|sshd|bantime": (0, 600),
    "get|sshd|findtime": (0, 600),
    "get|sshd|maxretry": (0, 5),
    "get|sshd|failregex": (0, ["regex1", "regex2"]),
    "get|sshd|ignoreregex": (0, []),
    "get|sshd|logpath": (0, ["/var/log/auth.log"]),
    "get|sshd|datepattern": (0, None),
    "get|sshd|logencoding": (0, "UTF-8"),
    "get|sshd|backend": (0, "polling"),
    "get|sshd|usedns": (0, "warn"),
    "get|sshd|prefregex": (0, ""),
    "get|sshd|actions": (0, ["iptables"]),
}


# ---------------------------------------------------------------------------
# get_jail_config
# ---------------------------------------------------------------------------


class TestGetJailConfig:
    """Unit tests for :func:`~app.services.config_service.get_jail_config`."""

    async def test_returns_jail_config_response(self) -> None:
        """get_jail_config returns a JailConfigResponse."""
        with _patch_client(_DEFAULT_JAIL_RESPONSES):
            result = await config_service.get_jail_config(_SOCKET, "sshd")

        assert isinstance(result, JailConfigResponse)
        assert result.jail.name == "sshd"
        assert result.jail.ban_time == 600
        assert result.jail.max_retry == 5
        assert result.jail.fail_regex == ["regex1", "regex2"]
        assert result.jail.log_paths == ["/var/log/auth.log"]

    async def test_raises_jail_not_found(self) -> None:
        """get_jail_config raises JailNotFoundError for an unknown jail."""

        async def _send(command: list[Any]) -> Any:
            raise Exception("Unknown jail 'missing'")

        class _FakeClient:
            def __init__(self, **_kw: Any) -> None:
                self.send = AsyncMock(side_effect=_send)

        # Patch the client to raise on status command.
        async def _faulty_send(command: list[Any]) -> Any:
            if command[0] == "status":
                return (1, "unknown jail 'missing'")
            return (0, None)

        with patch(
            "app.services.config_service.Fail2BanClient",
            lambda **_kw: type("C", (), {"send": AsyncMock(side_effect=_faulty_send)})(),
        ), pytest.raises(JailNotFoundError):
            await config_service.get_jail_config(_SOCKET, "missing")

    async def test_actions_parsed_correctly(self) -> None:
        """get_jail_config includes actions list."""
        with _patch_client(_DEFAULT_JAIL_RESPONSES):
            result = await config_service.get_jail_config(_SOCKET, "sshd")

        assert "iptables" in result.jail.actions

    async def test_empty_log_paths_fallback(self) -> None:
        """get_jail_config handles None log paths gracefully."""
        responses = {**_DEFAULT_JAIL_RESPONSES, "get|sshd|logpath": (0, None)}
        with _patch_client(responses):
            result = await config_service.get_jail_config(_SOCKET, "sshd")

        assert result.jail.log_paths == []

    async def test_date_pattern_none(self) -> None:
        """get_jail_config returns None date_pattern when not set."""
        with _patch_client(_DEFAULT_JAIL_RESPONSES):
            result = await config_service.get_jail_config(_SOCKET, "sshd")

        assert result.jail.date_pattern is None

    async def test_use_dns_populated(self) -> None:
        """get_jail_config returns use_dns from the socket response."""
        responses = {**_DEFAULT_JAIL_RESPONSES, "get|sshd|usedns": (0, "no")}
        with _patch_client(responses):
            result = await config_service.get_jail_config(_SOCKET, "sshd")

        assert result.jail.use_dns == "no"

    async def test_use_dns_default_when_missing(self) -> None:
        """get_jail_config defaults use_dns to 'warn' when socket returns None."""
        responses = {**_DEFAULT_JAIL_RESPONSES, "get|sshd|usedns": (0, None)}
        with _patch_client(responses):
            result = await config_service.get_jail_config(_SOCKET, "sshd")

        assert result.jail.use_dns == "warn"

    async def test_prefregex_populated(self) -> None:
        """get_jail_config returns prefregex from the socket response."""
        responses = {
            **_DEFAULT_JAIL_RESPONSES,
            "get|sshd|prefregex": (0, r"^%(__prefix_line)s"),
        }
        with _patch_client(responses):
            result = await config_service.get_jail_config(_SOCKET, "sshd")

        assert result.jail.prefregex == r"^%(__prefix_line)s"

    async def test_prefregex_empty_when_missing(self) -> None:
        """get_jail_config returns empty string prefregex when socket returns None."""
        responses = {**_DEFAULT_JAIL_RESPONSES, "get|sshd|prefregex": (0, None)}
        with _patch_client(responses):
            result = await config_service.get_jail_config(_SOCKET, "sshd")

        assert result.jail.prefregex == ""


# ---------------------------------------------------------------------------
# list_jail_configs
# ---------------------------------------------------------------------------


class TestListJailConfigs:
    """Unit tests for :func:`~app.services.config_service.list_jail_configs`."""

    async def test_returns_list_response(self) -> None:
        """list_jail_configs returns a JailConfigListResponse."""
        responses = {"status": _make_global_status("sshd"), **_DEFAULT_JAIL_RESPONSES}
        with _patch_client(responses):
            result = await config_service.list_jail_configs(_SOCKET)

        assert isinstance(result, JailConfigListResponse)
        assert result.total == 1
        assert result.jails[0].name == "sshd"

    async def test_empty_when_no_jails(self) -> None:
        """list_jail_configs returns empty list when no jails are active."""
        responses = {"status": (0, [("Jail list", ""), ("Number of jail", 0)])}
        with _patch_client(responses):
            result = await config_service.list_jail_configs(_SOCKET)

        assert result.total == 0
        assert result.jails == []

    async def test_multiple_jails(self) -> None:
        """list_jail_configs handles comma-separated jail names."""
        nginx_responses = {
            k.replace("sshd", "nginx"): v for k, v in _DEFAULT_JAIL_RESPONSES.items()
        }
        responses = {
            "status": _make_global_status("sshd, nginx"),
            **_DEFAULT_JAIL_RESPONSES,
            **nginx_responses,
        }
        with _patch_client(responses):
            result = await config_service.list_jail_configs(_SOCKET)

        assert result.total == 2
        names = {j.name for j in result.jails}
        assert names == {"sshd", "nginx"}


# ---------------------------------------------------------------------------
# update_jail_config
# ---------------------------------------------------------------------------


class TestUpdateJailConfig:
    """Unit tests for :func:`~app.services.config_service.update_jail_config`."""

    async def test_updates_numeric_fields(self) -> None:
        """update_jail_config sends set commands for numeric fields."""
        sent_commands: list[list[Any]] = []

        async def _send(command: list[Any]) -> Any:
            sent_commands.append(command)
            return (0, "OK")

        class _FakeClient:
            def __init__(self, **_kw: Any) -> None:
                self.send = AsyncMock(side_effect=_send)

        from app.models.config import JailConfigUpdate

        update = JailConfigUpdate(ban_time=3600, max_retry=10)
        with patch("app.services.config_service.Fail2BanClient", _FakeClient):
            await config_service.update_jail_config(_SOCKET, "sshd", update)

        keys = [cmd[2] for cmd in sent_commands if len(cmd) >= 3 and cmd[0] == "set"]
        assert "bantime" in keys
        assert "maxretry" in keys

    async def test_raises_validation_error_on_bad_regex(self) -> None:
        """update_jail_config raises ConfigValidationError for invalid regex."""
        from app.models.config import JailConfigUpdate

        update = JailConfigUpdate(fail_regex=["[invalid"])
        with pytest.raises(ConfigValidationError, match="Invalid regex"):
            await config_service.update_jail_config(_SOCKET, "sshd", update)

    async def test_skips_none_fields(self) -> None:
        """update_jail_config does not send commands for None fields."""
        sent_commands: list[list[Any]] = []

        async def _send(command: list[Any]) -> Any:
            sent_commands.append(command)
            return (0, "OK")

        class _FakeClient:
            def __init__(self, **_kw: Any) -> None:
                self.send = AsyncMock(side_effect=_send)

        from app.models.config import JailConfigUpdate

        update = JailConfigUpdate(ban_time=None, max_retry=None, find_time=None)
        with patch("app.services.config_service.Fail2BanClient", _FakeClient):
            await config_service.update_jail_config(_SOCKET, "sshd", update)

        set_commands = [cmd for cmd in sent_commands if len(cmd) >= 3 and cmd[0] == "set"]
        assert set_commands == []

    async def test_replaces_fail_regex(self) -> None:
        """update_jail_config deletes old regexes and adds new ones."""
        sent_commands: list[list[Any]] = []

        async def _send(command: list[Any]) -> Any:
            sent_commands.append(command)
            if command[0] == "get":
                return (0, ["old_pattern"])
            return (0, "OK")

        class _FakeClient:
            def __init__(self, **_kw: Any) -> None:
                self.send = AsyncMock(side_effect=_send)

        from app.models.config import JailConfigUpdate

        update = JailConfigUpdate(fail_regex=["new_pattern"])
        with patch("app.services.config_service.Fail2BanClient", _FakeClient):
            await config_service.update_jail_config(_SOCKET, "sshd", update)

        add_cmd = next(
            (c for c in sent_commands if len(c) >= 4 and c[2] == "addfailregex"),
            None,
        )
        assert add_cmd is not None
        assert add_cmd[3] == "new_pattern"

    async def test_sets_dns_mode(self) -> None:
        """update_jail_config sends 'set <jail> usedns' for dns_mode."""
        from app.models.config import JailConfigUpdate

        sent_commands: list[list[Any]] = []

        async def _send(command: list[Any]) -> Any:
            sent_commands.append(command)
            return (0, "OK")

        class _FakeClient:
            def __init__(self, **_kw: Any) -> None:
                self.send = AsyncMock(side_effect=_send)

        update = JailConfigUpdate(dns_mode="no")
        with patch("app.services.config_service.Fail2BanClient", _FakeClient):
            await config_service.update_jail_config(_SOCKET, "sshd", update)

        usedns_cmd = next(
            (c for c in sent_commands if len(c) >= 4 and c[2] == "usedns"),
            None,
        )
        assert usedns_cmd is not None
        assert usedns_cmd[3] == "no"

    async def test_sets_prefregex(self) -> None:
        """update_jail_config sends 'set <jail> prefregex' for prefregex."""
        from app.models.config import JailConfigUpdate

        sent_commands: list[list[Any]] = []

        async def _send(command: list[Any]) -> Any:
            sent_commands.append(command)
            return (0, "OK")

        class _FakeClient:
            def __init__(self, **_kw: Any) -> None:
                self.send = AsyncMock(side_effect=_send)

        update = JailConfigUpdate(prefregex=r"^%(__prefix_line)s")
        with patch("app.services.config_service.Fail2BanClient", _FakeClient):
            await config_service.update_jail_config(_SOCKET, "sshd", update)

        prefregex_cmd = next(
            (c for c in sent_commands if len(c) >= 4 and c[2] == "prefregex"),
            None,
        )
        assert prefregex_cmd is not None
        assert prefregex_cmd[3] == r"^%(__prefix_line)s"

    async def test_skips_none_prefregex(self) -> None:
        """update_jail_config does not send prefregex command when field is None."""
        from app.models.config import JailConfigUpdate

        sent_commands: list[list[Any]] = []

        async def _send(command: list[Any]) -> Any:
            sent_commands.append(command)
            return (0, "OK")

        class _FakeClient:
            def __init__(self, **_kw: Any) -> None:
                self.send = AsyncMock(side_effect=_send)

        update = JailConfigUpdate(prefregex=None)
        with patch("app.services.config_service.Fail2BanClient", _FakeClient):
            await config_service.update_jail_config(_SOCKET, "sshd", update)

        prefregex_cmd = next(
            (c for c in sent_commands if len(c) >= 4 and c[2] == "prefregex"),
            None,
        )
        assert prefregex_cmd is None

    async def test_raises_validation_error_on_invalid_prefregex(self) -> None:
        """update_jail_config raises ConfigValidationError for an invalid prefregex."""
        from app.models.config import JailConfigUpdate

        update = JailConfigUpdate(prefregex="[invalid")
        with pytest.raises(ConfigValidationError, match="prefregex"):
            await config_service.update_jail_config(_SOCKET, "sshd", update)


# ---------------------------------------------------------------------------
# get_global_config
# ---------------------------------------------------------------------------


class TestGetGlobalConfig:
    """Unit tests for :func:`~app.services.config_service.get_global_config`."""

    async def test_returns_global_config(self) -> None:
        """get_global_config returns parsed GlobalConfigResponse."""
        responses = {
            "get|loglevel": (0, "WARNING"),
            "get|logtarget": (0, "/var/log/fail2ban.log"),
            "get|dbpurgeage": (0, 86400),
            "get|dbmaxmatches": (0, 10),
        }
        with _patch_client(responses):
            result = await config_service.get_global_config(_SOCKET)

        assert result.log_level == "WARNING"
        assert result.log_target == "/var/log/fail2ban.log"
        assert result.db_purge_age == 86400
        assert result.db_max_matches == 10

    async def test_defaults_used_on_error(self) -> None:
        """get_global_config uses fallback defaults when commands fail."""
        responses: dict[str, Any] = {}
        with _patch_client(responses):
            result = await config_service.get_global_config(_SOCKET)

        assert result.log_level is not None
        assert result.log_target is not None


# ---------------------------------------------------------------------------
# update_global_config
# ---------------------------------------------------------------------------


class TestUpdateGlobalConfig:
    """Unit tests for :func:`~app.services.config_service.update_global_config`."""

    async def test_sends_set_commands(self) -> None:
        """update_global_config sends set commands for non-None fields."""
        sent: list[list[Any]] = []

        async def _send(command: list[Any]) -> Any:
            sent.append(command)
            return (0, "OK")

        class _FakeClient:
            def __init__(self, **_kw: Any) -> None:
                self.send = AsyncMock(side_effect=_send)

        update = GlobalConfigUpdate(log_level="debug", db_purge_age=3600)
        with patch("app.services.config_service.Fail2BanClient", _FakeClient):
            await config_service.update_global_config(_SOCKET, update)

        keys = [cmd[1] for cmd in sent if len(cmd) >= 3 and cmd[0] == "set"]
        assert "loglevel" in keys
        assert "dbpurgeage" in keys

    async def test_log_level_uppercased(self) -> None:
        """update_global_config uppercases log_level before sending."""
        sent: list[list[Any]] = []

        async def _send(command: list[Any]) -> Any:
            sent.append(command)
            return (0, "OK")

        class _FakeClient:
            def __init__(self, **_kw: Any) -> None:
                self.send = AsyncMock(side_effect=_send)

        update = GlobalConfigUpdate(log_level="debug")
        with patch("app.services.config_service.Fail2BanClient", _FakeClient):
            await config_service.update_global_config(_SOCKET, update)

        cmd = next(c for c in sent if len(c) >= 3 and c[1] == "loglevel")
        assert cmd[2] == "DEBUG"


# ---------------------------------------------------------------------------
# test_regex (synchronous)
# ---------------------------------------------------------------------------


class TestTestRegex:
    """Unit tests for :func:`~app.services.config_service.test_regex`."""

    def test_matching_pattern(self) -> None:
        """test_regex returns matched=True for a valid match."""
        req = RegexTestRequest(
            log_line="Failed password for user from 1.2.3.4",
            fail_regex=r"(?P<host>\d+\.\d+\.\d+\.\d+)",
        )
        result = config_service.test_regex(req)

        assert result.matched is True
        assert "1.2.3.4" in result.groups
        assert result.error is None

    def test_non_matching_pattern(self) -> None:
        """test_regex returns matched=False when pattern does not match."""
        req = RegexTestRequest(
            log_line="Normal log line here",
            fail_regex=r"BANME",
        )
        result = config_service.test_regex(req)

        assert result.matched is False
        assert result.groups == []

    def test_invalid_pattern_returns_error(self) -> None:
        """test_regex returns error message for an invalid regex."""
        req = RegexTestRequest(
            log_line="any line",
            fail_regex=r"[invalid",
        )
        result = config_service.test_regex(req)

        assert result.matched is False
        assert result.error is not None
        assert len(result.error) > 0

    def test_empty_groups_when_no_capture(self) -> None:
        """test_regex returns empty groups when pattern has no capture groups."""
        req = RegexTestRequest(
            log_line="fail here",
            fail_regex=r"fail",
        )
        result = config_service.test_regex(req)

        assert result.matched is True
        assert result.groups == []

    def test_multiple_capture_groups(self) -> None:
        """test_regex returns all captured groups."""
        req = RegexTestRequest(
            log_line="user=root ip=1.2.3.4",
            fail_regex=r"user=(\w+) ip=([\d.]+)",
        )
        result = config_service.test_regex(req)

        assert result.matched is True
        assert len(result.groups) == 2


# ---------------------------------------------------------------------------
# preview_log
# ---------------------------------------------------------------------------


class TestPreviewLog:
    """Unit tests for :func:`~app.services.config_service.preview_log`."""

    async def test_returns_error_for_invalid_regex(self, tmp_path: Any) -> None:
        """preview_log returns regex_error for an invalid pattern."""
        req = LogPreviewRequest(log_path=str(tmp_path / "fake.log"), fail_regex="[bad")
        result = await config_service.preview_log(req)

        assert result.regex_error is not None
        assert result.total_lines == 0

    async def test_returns_error_for_missing_file(self) -> None:
        """preview_log returns regex_error when file does not exist."""
        req = LogPreviewRequest(
            log_path="/nonexistent/path/log.txt",
            fail_regex=r"test",
        )
        result = await config_service.preview_log(req)

        assert result.regex_error is not None

    async def test_matches_lines_in_file(self, tmp_path: Any) -> None:
        """preview_log correctly identifies matching and non-matching lines."""
        log_file = tmp_path / "test.log"
        log_file.write_text("FAIL login from 1.2.3.4\nOK normal line\nFAIL from 5.6.7.8\n")

        req = LogPreviewRequest(log_path=str(log_file), fail_regex=r"FAIL")
        result = await config_service.preview_log(req)

        assert result.total_lines == 3
        assert result.matched_count == 2

    async def test_matched_line_has_groups(self, tmp_path: Any) -> None:
        """preview_log captures regex groups in matched lines."""
        log_file = tmp_path / "test.log"
        log_file.write_text("error from 1.2.3.4 port 22\n")

        req = LogPreviewRequest(
            log_path=str(log_file),
            fail_regex=r"from (\d+\.\d+\.\d+\.\d+)",
        )
        result = await config_service.preview_log(req)

        matched = [ln for ln in result.lines if ln.matched]
        assert len(matched) == 1
        assert "1.2.3.4" in matched[0].groups

    async def test_num_lines_limit(self, tmp_path: Any) -> None:
        """preview_log respects the num_lines limit."""
        log_file = tmp_path / "big.log"
        log_file.write_text("\n".join(f"line {i}" for i in range(500)) + "\n")

        req = LogPreviewRequest(log_path=str(log_file), fail_regex=r"line", num_lines=50)
        result = await config_service.preview_log(req)

        assert result.total_lines <= 50