from unittest.mock import patch

import pytest

from lib import 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 = dnsmasq._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 = dnsmasq._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 = dnsmasq._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 TestSetDhcpRange:
    def test_add_new_range(self, temp_data_dir):
        dnsmasq.set_dhcp_range("eth1", "192.168.1.100", "192.168.1.200")
        cfg = dnsmasq.get_config()
        assert len(cfg["dhcp"]["ranges"]) == 1
        assert cfg["dhcp"]["ranges"][0]["interface"] == "eth1"
        assert cfg["dhcp"]["ranges"][0]["start"] == "192.168.1.100"

    def test_replace_existing_range(self, temp_data_dir):
        dnsmasq.set_dhcp_range("eth1", "10.0.0.100", "10.0.0.200")
        dnsmasq.set_dhcp_range("eth1", "10.0.0.150", "10.0.0.250")
        cfg = dnsmasq.get_config()
        assert len(cfg["dhcp"]["ranges"]) == 1
        assert cfg["dhcp"]["ranges"][0]["start"] == "10.0.0.150"


class TestStaticLeases:
    def test_add_static_lease(self, temp_data_dir):
        dnsmasq.add_static_lease("AA:BB:CC:DD:EE:FF", "10.0.0.50", "printer")
        cfg = dnsmasq.get_config()
        assert len(cfg["dhcp"]["static_leases"]) == 1
        assert cfg["dhcp"]["static_leases"][0]["mac"] == "AA:BB:CC:DD:EE:FF"
        assert cfg["dhcp"]["static_leases"][0]["hostname"] == "printer"

    def test_update_static_lease(self, temp_data_dir):
        dnsmasq.add_static_lease("AA:BB:CC", "10.0.0.50")
        dnsmasq.add_static_lease("AA:BB:CC", "10.0.0.51")
        cfg = dnsmasq.get_config()
        assert len(cfg["dhcp"]["static_leases"]) == 1
        assert cfg["dhcp"]["static_leases"][0]["ip"] == "10.0.0.51"

    def test_remove_static_lease(self, temp_data_dir):
        dnsmasq.add_static_lease("AA:BB:CC", "10.0.0.50")
        dnsmasq.add_static_lease("11:22:33", "10.0.0.51")
        dnsmasq.remove_static_lease("aa:bb:cc")
        cfg = dnsmasq.get_config()
        assert len(cfg["dhcp"]["static_leases"]) == 1
        assert cfg["dhcp"]["static_leases"][0]["mac"] == "11:22:33"


class TestDnsRecords:
    def test_add_dns_record(self, temp_data_dir):
        dnsmasq.add_dns_record("host", "10.0.0.100")
        cfg = dnsmasq.get_config()
        assert len(cfg["dns"]["custom_records"]) == 1

    def test_remove_dns_record(self, temp_data_dir):
        dnsmasq.add_dns_record("host", "10.0.0.100")
        dnsmasq.add_dns_record("other", "10.0.0.101")
        dnsmasq.remove_dns_record("host")
        cfg = dnsmasq.get_config()
        assert len(cfg["dns"]["custom_records"]) == 1
        assert cfg["dns"]["custom_records"][0]["name"] == "other"


class TestParseLeaseLine:
    def test_valid_line(self):
        line = "1700000000 AA:BB:CC:DD:EE:FF 10.0.0.50 printer eth1"
        result = dnsmasq._parse_lease_line(line)
        assert result is not None
        assert result["mac"] == "AA:BB:CC:DD:EE:FF"
        assert result["ip"] == "10.0.0.50"
        assert result["hostname"] == "printer"

    def test_empty_line(self):
        assert dnsmasq._parse_lease_line("") is None

    def test_comment_line(self):
        assert dnsmasq._parse_lease_line("# comment") is None

    def test_short_line(self):
        assert dnsmasq._parse_lease_line("incomplete") is None

    def test_minimal_fields(self):
        line = "1700000000 AA:BB:CC 10.0.0.50"
        result = dnsmasq._parse_lease_line(line)
        assert result is not None
        assert result["hostname"] == ""
        assert result["interface"] == ""


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