from unittest.mock import patch

import pytest

from lib import common, dnsmasq


@pytest.fixture
def temp_data_dir(tmp_path):
    original_config_dir = dnsmasq.CONFIG_DIR
    original = dnsmasq.DATA_DIR
    original_config = dnsmasq.CONFIG_PATH
    original_fragments = dnsmasq.FRAGMENTS_DIR
    dnsmasq.CONFIG_DIR = tmp_path / "dnsmasq"
    dnsmasq.DATA_DIR = tmp_path / "dnsmasq"
    dnsmasq.CONFIG_PATH = dnsmasq.CONFIG_DIR / "config.json"
    dnsmasq.FRAGMENTS_DIR = dnsmasq.DATA_DIR / "fragments"
    dnsmasq.CONFIG_DIR.mkdir(parents=True, exist_ok=True)
    dnsmasq.DATA_DIR.mkdir(parents=True, exist_ok=True)
    dnsmasq.FRAGMENTS_DIR.mkdir(parents=True, exist_ok=True)
    yield tmp_path
    dnsmasq.CONFIG_DIR = original_config_dir
    dnsmasq.DATA_DIR = original
    dnsmasq.CONFIG_PATH = original_config
    dnsmasq.FRAGMENTS_DIR = original_fragments


class TestDeepMerge:
    def test_merge_flat_dicts(self):
        base = {"a": 1, "b": 2}
        override = {"b": 3, "c": 4}
        result = common.deep_merge(base, override)
        assert result == {"a": 1, "b": 3, "c": 4}

    def test_merge_nested_dicts(self):
        base = {"a": {"x": 1, "y": 2}}
        override = {"a": {"y": 3, "z": 4}}
        result = common.deep_merge(base, override)
        assert result == {"a": {"x": 1, "y": 3, "z": 4}}

    def test_merge_non_dict_override(self):
        base = {"a": {"x": 1}}
        override = {"a": "flat"}
        result = common.deep_merge(base, override)
        assert result == {"a": "flat"}


class TestGetConfig:
    @patch("lib.dnsmasq.load_json")
    def test_returns_default_when_no_config(self, mock_load, temp_data_dir):
        mock_load.return_value = {}
        result = dnsmasq.get_config()
        assert "dhcp" in result
        assert "dns" in result
        assert result["dns"]["upstreams"] == ["8.8.8.8", "1.1.1.1"]

    @patch("lib.dnsmasq.load_json")
    def test_merges_with_existing_config(self, mock_load, temp_data_dir):
        mock_load.return_value = {"dns": {"upstreams": ["9.9.9.9"]}}
        result = dnsmasq.get_config()
        assert result["dns"]["upstreams"] == ["9.9.9.9"]


class TestSaveConfig:
    def test_saves_and_reloads(self, temp_data_dir):
        cfg = {"dns": {"upstreams": ["1.2.3.4"], "domain": "test.lan"}}
        dnsmasq.save_config(cfg)
        loaded = dnsmasq.get_config()
        assert loaded["dns"]["upstreams"] == ["1.2.3.4"]
        assert loaded["dns"]["domain"] == "test.lan"


class TestUpstreamsAndDomain:
    def test_set_upstreams(self, temp_data_dir):
        dnsmasq.set_upstreams(["1.1.1.1", "9.9.9.9"])
        cfg = dnsmasq.get_config()
        assert cfg["dns"]["upstreams"] == ["1.1.1.1", "9.9.9.9"]

    def test_set_domain(self, temp_data_dir):
        dnsmasq.set_domain("internal.lan")
        cfg = dnsmasq.get_config()
        assert cfg["dns"]["domain"] == "internal.lan"

    def test_clear_domain(self, temp_data_dir):
        dnsmasq.set_domain("internal.lan")
        dnsmasq.set_domain(None)
        cfg = dnsmasq.get_config()
        assert cfg["dns"]["domain"] is None


# ── Daemon handler tests (NotFoundError on missing resources) ──


class TestDaemonRemoveStaticLease:
    @patch("daemon.handlers.dnsmasq._get_config")
    @patch("daemon.handlers.dnsmasq._save_config")
    def test_raises_not_found_when_missing(self, mock_save, mock_get):
        from daemon.handlers import dnsmasq as daemon_dnsmasq

        mock_get.return_value = {"dhcp": {"static_leases": []}, "dns": {}}
        with pytest.raises(Exception, match="not found"):
            daemon_dnsmasq.remove_static_lease(None, {"mac": "FF:FF:FF"})

    @patch("daemon.handlers.dnsmasq._get_config")
    @patch("daemon.handlers.dnsmasq._save_config")
    def test_succeeds_when_exists(self, mock_save, mock_get):
        from daemon.handlers import dnsmasq as daemon_dnsmasq

        mock_get.return_value = {
            "dhcp": {"static_leases": [{"mac": "aa:bb:cc", "ip": "10.0.0.1"}]},
            "dns": {},
        }
        result = daemon_dnsmasq.remove_static_lease(None, {"mac": "AA:BB:CC"})
        assert result["mac"] == "AA:BB:CC"


class TestDaemonRemoveDnsRecord:
    @patch("daemon.handlers.dnsmasq._get_config")
    @patch("daemon.handlers.dnsmasq._save_config")
    def test_raises_not_found_when_missing(self, mock_save, mock_get):
        from daemon.handlers import dnsmasq as daemon_dnsmasq

        mock_get.return_value = {
            "dhcp": {},
            "dns": {"custom_records": []},
        }
        with pytest.raises(Exception, match="not found"):
            daemon_dnsmasq.remove_dns_record(None, {"name": "nonexistent"})

    @patch("daemon.handlers.dnsmasq._get_config")
    @patch("daemon.handlers.dnsmasq._save_config")
    def test_succeeds_when_exists(self, mock_save, mock_get):
        from daemon.handlers import dnsmasq as daemon_dnsmasq

        mock_get.return_value = {
            "dhcp": {},
            "dns": {"custom_records": [{"name": "host", "address": "10.0.0.1"}]},
        }
        result = daemon_dnsmasq.remove_dns_record(None, {"name": "host"})
        assert result["name"] == "host"


class TestDaemonRemoveDhcpRange:
    @patch("daemon.handlers.dnsmasq._get_config")
    @patch("daemon.handlers.dnsmasq._save_config")
    def test_raises_not_found_when_missing(self, mock_save, mock_get):
        from daemon.handlers import dnsmasq as daemon_dnsmasq

        mock_get.return_value = {
            "dhcp": {"ranges": []},
            "dns": {},
        }
        with pytest.raises(Exception, match="not found"):
            daemon_dnsmasq.remove_dhcp_range(
                None,
                {
                    "interface": "eth0",
                    "start": "10.0.0.100",
                    "end": "10.0.0.200",
                },
            )

    @patch("daemon.handlers.dnsmasq._get_config")
    @patch("daemon.handlers.dnsmasq._save_config")
    def test_succeeds_when_exists(self, mock_save, mock_get):
        from daemon.handlers import dnsmasq as daemon_dnsmasq

        mock_get.return_value = {
            "dhcp": {
                "ranges": [
                    {
                        "interface": "eth0",
                        "start": "10.0.0.100",
                        "end": "10.0.0.200",
                    }
                ]
            },
            "dns": {},
        }
        result = daemon_dnsmasq.remove_dhcp_range(
            None,
            {
                "interface": "eth0",
                "start": "10.0.0.100",
                "end": "10.0.0.200",
            },
        )
        assert result["interface"] == "eth0"