import sys
from pathlib import Path
import unittest

sys.path.insert(0, str(Path(__file__).resolve().parents[3] / 'python'))
from logic_analyzer.decoders.transistor_pair import PairTimingChecker


class TransistorPairTests(unittest.TestCase):
    def test_directional_deadtime_limits_and_equality(self):
        c = PairTimingChecker(1e9, deadtime_12_ns=30, deadtime_21_ns=50)
        c.update(0, 0, 0)
        c.update(10, 1, 0)
        c.update(110, 0, 0)
        events = c.update(140, 0, 1)
        self.assertEqual(events[0]['kind'], 'deadtime')
        self.assertEqual(events[0]['duration_ns'], 30)
        c.update(240, 0, 0)
        self.assertEqual(c.update(280, 1, 0)[0]['kind'], 'deadtime_fail')

    def test_independent_on_off_times_frequency_and_duty(self):
        c = PairTimingChecker(1e9, vin1_mintime_ns=100, vin2_mintime_ns=101,
                             vin1_minoff_ns=201, vin2_minoff_ns=50)
        c.update(0, 0, 0)
        c.update(10, 1, 0)
        self.assertEqual(c.update(110, 0, 0)[0]['kind'], 'mintime_ok')
        c.update(140, 0, 1)
        self.assertEqual(c.update(240, 0, 0)[0]['kind'], 'mintime_fail')
        events = c.update(310, 1, 0)
        self.assertTrue(any(e['kind'] == 'off_fail' for e in events))
        period = next(e for e in events if e['kind'] == 'period')
        self.assertAlmostEqual(period['frequency_hz'], 1e9/300)
        self.assertAlmostEqual(period['duty_percent'], 100/3)
        self.assertEqual((period['start'], period['end']), (10, 310))

    def test_atomic_handover_active_low_and_overlap(self):
        c = PairTimingChecker(1e9, False, False, deadtime_12_ns=1)
        c.update(0, 1, 1)
        c.update(10, 0, 1)
        events = c.update(20, 1, 0)
        self.assertTrue(any(e['kind'] == 'deadtime_fail' and e['duration_ns'] == 0 for e in events))
        c.update(30, 0, 0)
        self.assertEqual(c.finish(50)[0]['kind'], 'overlap')
        self.assertTrue(any(e['kind'] == 'overlap' for e in c.update(60, 1, 0)))

    def test_capture_boundary_does_not_invent_complete_pulses(self):
        c = PairTimingChecker(1e9)
        self.assertEqual(c.update(0, 1, 0), [])
        self.assertEqual(c.update(10, 0, 0), [])
        events = c.update(20, 1, 0)
        self.assertEqual([e['kind'] for e in events], ['off_time'])
        self.assertEqual(c.finish(30), [])

    def test_invalid_limits(self):
        for name in ('deadtime_12_ns', 'deadtime_21_ns', 'vin1_minoff_ns', 'vin2_minoff_ns'):
            for value in (-1, float('nan'), float('inf')):
                with self.subTest(name=name, value=value), self.assertRaises(ValueError):
                    PairTimingChecker(1e9, **{name: value})