from decimal import Decimal
from pathlib import Path
import tempfile
import unittest
import zipfile

from logic_analyzer.csv_import import convert_csv
from logic_analyzer.files import ImportCancelled, read_capture


class CsvImportTests(unittest.TestCase):
    def setUp(self):
        self.temp = tempfile.TemporaryDirectory()
        self.addCleanup(self.temp.cleanup)
        self.source = Path(self.temp.name) / 'сигналы.csv'
        self.output = Path(self.temp.name) / 'сигналы.dsl'

    def write(self, value):
        self.source.write_text(value, encoding='utf-8-sig')

    def test_regular_samples_preserve_levels_and_names(self):
        self.write('Time [ns],Vin,Vstat\n0,0,1\n10,1,0\n20,0,1\n')
        original = self.source.read_bytes()
        info = convert_csv(self.source, self.output)
        result = read_capture(self.output)
        self.assertEqual(info['samplerate'], 100_000_000)
        self.assertEqual([c.name for c in result.channels], ['Vin', 'Vstat'])
        self.assertEqual(list(result.channels[0].edges), [1e-8, 2e-8])
        self.assertEqual([result.channels[1].level_at(t) for t in [0, 1e-8, 2e-8, 5e-7]], [1, 0, 1, 1])
        self.assertEqual(self.source.read_bytes(), original)

    def test_sparse_transitions_preserve_short_pulses_across_blocks(self):
        self.write('Time [ns],A\n0,0\n10,1\n650,0\n680,1\n710,0\n')
        convert_csv(self.source, self.output, block_samples=64)
        capture = read_capture(self.output)
        self.assertEqual(list(capture.channels[0].edges), [1e-8, 6.5e-7, 6.8e-7, 7.1e-7])
        with zipfile.ZipFile(self.output) as archive:
            self.assertIn('L-0/1', archive.namelist())
            self.assertEqual(len(archive.read('L-0/0')), 8)

    def test_initial_snapshot_need_not_be_on_edge_clock(self):
        self.write('Time [s];A\n127,632374014;0\n127,632482000;1\n127,632482400;0\n127,632483000;1\n')
        info = convert_csv(self.source, self.output)
        self.assertEqual(info['samplerate'], 5_000_000)
        self.assertEqual(Decimal(info['origin_seconds']), Decimal('127.632374'))
        capture = read_capture(self.output)
        edges = capture.channels[0].edges
        self.assertAlmostEqual(edges[1] - edges[0], 400e-9, places=14)
        self.assertAlmostEqual(edges[2] - edges[1], 600e-9, places=14)

    def test_comments_tab_delimiter_and_negative_origin(self):
        self.write('; DSView export\n# data\nTime(us)\tКанал\n-1\t1\n0\t0\n1\t1\n')
        info = convert_csv(self.source, self.output)
        self.assertEqual(info['origin_seconds'], '-0.000001')
        self.assertEqual(read_capture(self.output).channels[0].name, 'Канал')

    def test_bad_csv_leaves_no_output(self):
        for rows in ('0,0\n1,3.3', '0,0\n0,1', 'nan,0\n1,1', '0,0', '0,0,1\n1,1,0'):
            with self.subTest(rows=rows):
                self.write('Time [s],A\n' + rows + '\n')
                with self.assertRaises(ValueError):
                    convert_csv(self.source, self.output)
                self.assertFalse(self.output.exists())

    def test_output_is_not_overwritten_and_size_limit_precedes_expansion(self):
        self.write('Time [ns],A\n0,0\n10,1\n100000,0\n')
        with self.assertRaises(ValueError):
            convert_csv(self.source, self.output, max_packed_bytes=64)
        self.output.write_bytes(b'old recording')
        with self.assertRaises(ValueError):
            convert_csv(self.source, self.output)
        self.assertEqual(self.output.read_bytes(), b'old recording')

    def test_cancel_during_packing_cleans_temporary_output(self):
        self.write('Time [ns],A\n0,0\n10,1\n100000,0\n')
        cancelled = False
        def progress(value):
            nonlocal cancelled
            if value > 40:
                cancelled = True
        with self.assertRaises(ImportCancelled):
            convert_csv(self.source, self.output, progress, lambda: cancelled, block_samples=64)
        self.assertFalse(self.output.exists())
        self.assertEqual([p.name for p in Path(self.temp.name).iterdir()], [self.source.name])

    def test_changed_source_rejected_before_publication(self):
        self.write('Time [ns],A\n0,0\n10,1\n20,0\n')
        changed = False
        def progress(value):
            nonlocal changed
            if value == 99 and not changed:
                changed = True
                self.source.write_text('changed', encoding='utf-8')
        with self.assertRaisesRegex(ValueError, 'изменился'):
            convert_csv(self.source, self.output, progress)
        self.assertFalse(self.output.exists())