"""Tests for stream connection state machine."""

import pytest


class TestConnectionState:
    def test_enum_values(self):
        from i2p_streaming.connection import ConnectionState
        states = ["NEW", "SYN_SENT", "SYN_RECEIVED", "ESTABLISHED",
                  "CLOSE_WAIT", "LAST_ACK", "FIN_WAIT", "CLOSING",
                  "TIME_WAIT", "CLOSED", "RESET"]
        for name in states:
            assert hasattr(ConnectionState, name)


class TestStreamConnection:
    def test_initial_state(self):
        from i2p_streaming.connection import StreamConnection, ConnectionState
        conn = StreamConnection()
        assert conn.state == ConnectionState.NEW

    def test_active_open(self):
        from i2p_streaming.connection import StreamConnection, ConnectionState
        conn = StreamConnection()
        conn.send_syn()
        assert conn.state == ConnectionState.SYN_SENT

    def test_passive_open(self):
        from i2p_streaming.connection import StreamConnection, ConnectionState
        conn = StreamConnection()
        conn.receive_syn()
        assert conn.state == ConnectionState.SYN_RECEIVED

    def test_active_open_established(self):
        from i2p_streaming.connection import StreamConnection, ConnectionState
        conn = StreamConnection()
        conn.send_syn()
        conn.receive_syn_ack()
        assert conn.state == ConnectionState.ESTABLISHED

    def test_passive_open_established(self):
        from i2p_streaming.connection import StreamConnection, ConnectionState
        conn = StreamConnection()
        conn.receive_syn()
        conn.send_syn_ack()
        assert conn.state == ConnectionState.ESTABLISHED

    def test_active_close(self):
        from i2p_streaming.connection import StreamConnection, ConnectionState
        conn = StreamConnection()
        conn.send_syn()
        conn.receive_syn_ack()
        conn.send_close()
        assert conn.state == ConnectionState.FIN_WAIT

    def test_passive_close(self):
        from i2p_streaming.connection import StreamConnection, ConnectionState
        conn = StreamConnection()
        conn.send_syn()
        conn.receive_syn_ack()
        conn.receive_close()
        assert conn.state == ConnectionState.CLOSE_WAIT

    def test_close_wait_to_last_ack(self):
        from i2p_streaming.connection import StreamConnection, ConnectionState
        conn = StreamConnection()
        conn.send_syn()
        conn.receive_syn_ack()
        conn.receive_close()
        conn.send_close()
        assert conn.state == ConnectionState.LAST_ACK

    def test_last_ack_to_closed(self):
        from i2p_streaming.connection import StreamConnection, ConnectionState
        conn = StreamConnection()
        conn.send_syn()
        conn.receive_syn_ack()
        conn.receive_close()
        conn.send_close()
        conn.receive_ack()
        assert conn.state == ConnectionState.CLOSED

    def test_fin_wait_to_time_wait(self):
        from i2p_streaming.connection import StreamConnection, ConnectionState
        conn = StreamConnection()
        conn.send_syn()
        conn.receive_syn_ack()
        conn.send_close()
        conn.receive_close_ack()
        assert conn.state == ConnectionState.TIME_WAIT

    def test_time_wait_to_closed(self):
        from i2p_streaming.connection import StreamConnection, ConnectionState
        conn = StreamConnection()
        conn.send_syn()
        conn.receive_syn_ack()
        conn.send_close()
        conn.receive_close_ack()
        conn.timeout()
        assert conn.state == ConnectionState.CLOSED

    def test_reset(self):
        from i2p_streaming.connection import StreamConnection, ConnectionState
        conn = StreamConnection()
        conn.send_syn()
        conn.receive_syn_ack()
        conn.reset()
        assert conn.state == ConnectionState.RESET

    def test_invalid_transition(self):
        from i2p_streaming.connection import StreamConnection
        conn = StreamConnection()
        with pytest.raises(RuntimeError):
            conn.receive_syn_ack()  # Can't receive SYN_ACK from NEW

    def test_invalid_close_from_new(self):
        from i2p_streaming.connection import StreamConnection
        conn = StreamConnection()
        with pytest.raises(RuntimeError):
            conn.send_close()

    def test_sequence_numbers(self):
        from i2p_streaming.connection import StreamConnection
        conn = StreamConnection()
        assert conn.next_send_seq == 0
        conn.increment_send_seq()
        assert conn.next_send_seq == 1

    def test_send_window(self):
        from i2p_streaming.connection import StreamConnection
        from i2p_streaming.options import StreamOptions
        opts = StreamOptions(initial_window_size=10)
        conn = StreamConnection(options=opts)
        assert conn.send_window == 10

    def test_receive_window(self):
        from i2p_streaming.connection import StreamConnection
        from i2p_streaming.options import StreamOptions
        opts = StreamOptions(initial_window_size=8)
        conn = StreamConnection(options=opts)
        assert conn.recv_window == 8