"""Tests for FlightCorrelator: ACARS/VDL2 message matching."""

import pytest

from utils.flight_correlator import FlightCorrelator


class TestFlightCorrelator:
    """Test ACARS/VDL2 message matching by callsign."""

    @pytest.fixture(autouse=True)
    def setup(self):
        self.correlator = FlightCorrelator(max_messages=100)

    def test_add_acars_message(self):
        self.correlator.add_acars_message(
            {
                "flight": "BAW123",
                "tail": "G-ABCD",
                "text": "Hello",
            }
        )
        assert self.correlator.acars_count == 1

    def test_add_vdl2_message(self):
        self.correlator.add_vdl2_message(
            {
                "flight": "DLH456",
                "text": "World",
            }
        )
        assert self.correlator.vdl2_count == 1

    def test_match_by_callsign(self):
        self.correlator.add_acars_message(
            {
                "flight": "BAW123",
                "text": "msg1",
            }
        )
        self.correlator.add_acars_message(
            {
                "flight": "DLH456",
                "text": "msg2",
            }
        )

        result = self.correlator.get_messages_for_aircraft(callsign="BAW123")
        assert len(result["acars"]) == 1
        assert result["acars"][0]["text"] == "msg1"

    def test_match_by_icao(self):
        self.correlator.add_vdl2_message(
            {
                "icao": "ABC123",
                "text": "vdl2 msg",
            }
        )

        result = self.correlator.get_messages_for_aircraft(icao="ABC123")
        assert len(result["vdl2"]) == 1
        assert result["vdl2"][0]["text"] == "vdl2 msg"

    def test_no_match_returns_empty(self):
        self.correlator.add_acars_message({"flight": "BAW123", "text": "msg"})

        result = self.correlator.get_messages_for_aircraft(callsign="NOMATCH")
        assert result["acars"] == []
        assert result["vdl2"] == []

    def test_empty_search_returns_empty(self):
        result = self.correlator.get_messages_for_aircraft()
        assert result == {"acars": [], "vdl2": []}

    def test_ring_buffer_limit(self):
        correlator = FlightCorrelator(max_messages=5)
        for i in range(10):
            correlator.add_acars_message({"flight": f"FL{i}", "text": f"msg{i}"})

        assert correlator.acars_count == 5
        # First 5 messages should have been evicted
        result = correlator.get_messages_for_aircraft(callsign="FL0")
        assert len(result["acars"]) == 0
        # Last message should still be there
        result = correlator.get_messages_for_aircraft(callsign="FL9")
        assert len(result["acars"]) == 1

    def test_case_insensitive_matching(self):
        self.correlator.add_acars_message({"flight": "baw123", "text": "lowercase"})

        result = self.correlator.get_messages_for_aircraft(callsign="BAW123")
        assert len(result["acars"]) == 1

    def test_match_by_tail_field(self):
        self.correlator.add_acars_message(
            {
                "tail": "G-ABCD",
                "text": "tail match",
            }
        )

        result = self.correlator.get_messages_for_aircraft(callsign="G-ABCD")
        assert len(result["acars"]) == 1

    def test_internal_fields_not_returned(self):
        self.correlator.add_acars_message({"flight": "TEST", "text": "msg"})

        result = self.correlator.get_messages_for_aircraft(callsign="TEST")
        msg = result["acars"][0]
        assert "_corr_time" not in msg

    def test_both_acars_and_vdl2_returned(self):
        self.correlator.add_acars_message({"flight": "UAL789", "text": "acars"})
        self.correlator.add_vdl2_message({"flight": "UAL789", "text": "vdl2"})

        result = self.correlator.get_messages_for_aircraft(callsign="UAL789")
        assert len(result["acars"]) == 1
        assert len(result["vdl2"]) == 1