import ctypes
import json
import os
import unittest
from dataclasses import replace
from pathlib import Path

from protocan.trends import (
    MAX_FILE_BYTES, MAX_POINTS, NativeTrends, TrendHistory, TrendSignal,
    decode_settings, encode_settings, parse_address,
)

FIXTURE = Path(__file__).resolve().parents[2] / "c/set-protocol/tests/fixtures/trends-v1.json"


class TrendTests(unittest.TestCase):
    def test_shared_kotlin_fixture_and_round_trip(self):
        settings = decode_settings(FIXTURE.read_text(encoding="utf-8"))
        self.assertEqual(5, sum(map(len, settings.values())))
        self.assertEqual("Ток фазы А", settings["TMS2812"][0].name)
        self.assertEqual(settings, decode_settings(encode_settings(settings)))
        self.assertEqual(settings, decode_settings("\ufeff" + encode_settings(settings)))

    def test_profile_specific_defaults(self):
        self.assertEqual("SET_GAS", TrendSignal.new("SET_V1").source)
        self.assertEqual("CAN_RAW", TrendSignal.new("BALZAM_CAN").source)
        self.assertEqual("CAN_GAS", TrendSignal.new("SLCAN").source)

    def test_invalid_import_and_types(self):
        fixture = FIXTURE.read_text(encoding="utf-8")
        for field, value in (("order", "1"), ("order", 1.5), ("order", True),
                             ("visible", "true"), ("color", "red"),
                             ("source", "CAN_GAS"), ("address", "0x100000000")):
            with self.subTest(field=field, value=value), self.assertRaises(ValueError):
                data = json.loads(fixture)
                data["profiles"]["TMS2812"][0][field] = value
                decode_settings(json.dumps(data))
        for version in (2, "1", 1.5, True):
            with self.assertRaises(ValueError):
                data = json.loads(fixture)
                data["version"] = version
                decode_settings(json.dumps(data))
        with self.assertRaises(ValueError):
            decode_settings(" " * (MAX_FILE_BYTES + 1))

    def test_duplicates_and_limits(self):
        signal = TrendSignal("one")
        for signals in ([signal, replace(signal, id="two")],
                        [signal, replace(signal, order=2)],
                        [replace(signal, id=str(i), order=i + 1) for i in range(65)]):
            with self.assertRaises(ValueError):
                encode_settings({"TMS2812": signals})

    def test_addresses_and_signedness(self):
        self.assertEqual(255, parse_address("0xFF", 255))
        self.assertEqual(100, parse_address("100", 100))
        for value in ("-1", "+1", "FF", "0x", "1.0", "256"):
            with self.assertRaises(ValueError):
                parse_address(value, 255)
        self.assertEqual(-2.0, TrendSignal("s", valueType="INT16").word_value(65534))

    def test_bounded_history(self):
        history = TrendHistory()
        for i in range(MAX_POINTS + 10):
            history.append({"a": float(i), "bad": float("nan")}, i)
        self.assertEqual(MAX_POINTS, len(history.series["a"]))
        self.assertEqual((10, 10.0), history.series["a"][0])
        self.assertNotIn("bad", history.series)

    @unittest.skipUnless(os.environ.get("SETPROTOCOL_LIBRARY"), "Host DLL not supplied")
    def test_actual_shared_c_core(self):
        core = NativeTrends(ctypes.CDLL(os.environ["SETPROTOCOL_LIBRARY"]))
        signal = TrendSignal("gas", source="CAN_GAS", address="0x1235", valueType="INT16")
        frame_id = 0x1FD31234
        data = bytes([1, 0, 254, 255])
        self.assertEqual(-2.0, core.can_value(signal, frame_id, 1, data))
        self.assertEqual(65534.0, core.can_value(replace(signal, valueType="UINT16"), frame_id, 1, data))
        self.assertIsNone(core.can_value(replace(signal, device=12), frame_id, 1, data))
        for flag in (2, 4, 8):
            self.assertIsNone(core.can_value(signal, frame_id, 1 | flag, data))
        self.assertIsNone(core.can_value(signal, frame_id ^ 0x08000000, 1, data))
        raw = replace(signal, source="CAN_RAW", address="0x321", extended=False, byteOffset=2)
        self.assertEqual(-2.0, core.can_value(raw, 0x321, 0, data))


if __name__ == "__main__":
    unittest.main()