from __future__ import annotations

import copy
import importlib.util
from pathlib import Path
import sys
import unittest

SOURCE_ROOT = Path(__file__).resolve().parents[1]
sys.path.insert(0, str(SOURCE_ROOT / "src"))

from matrix_image_editor.config import (  # noqa: E402
    HEADER_BYTES,
    SLOT_BYTES,
    ImageConfigError,
    create_config_file,
    read_config_file,
    update_config_file,
    validate_config,
)


def sample_config() -> dict:
    return {
        "schema_version": 1,
        "product": "matrix-screen-controller-walnutpi",
        "software_version": "1.0.3",
        "account": {"username": "matrix", "password": "password123"},
        "wifi": {"ssid": "测试 WiFi", "password": "wifi-pass-123"},
        "ipv4": {"mode": "dhcp", "address": "", "prefix": 0, "gateway": "", "dns": []},
    }


class ConfigTests(unittest.TestCase):
    def test_round_trip_and_update_inactive_slot(self) -> None:
        original = create_config_file(sample_config())
        config, generation, slot = read_config_file(original)
        self.assertEqual((generation, slot), (1, 0))
        config["wifi"]["ssid"] = "新网络"
        updated = update_config_file(original, config)
        verified, generation, slot = read_config_file(updated)
        self.assertEqual((generation, slot, verified["wifi"]["ssid"]), (2, 1, "新网络"))
        self.assertEqual(updated[HEADER_BYTES : HEADER_BYTES + SLOT_BYTES], original[HEADER_BYTES : HEADER_BYTES + SLOT_BYTES])

    def test_corrupt_active_slot_falls_back_and_both_corrupt_fail(self) -> None:
        original = create_config_file(sample_config())
        updated = bytearray(update_config_file(original, sample_config()))
        updated[HEADER_BYTES + SLOT_BYTES + 60] ^= 0x01
        _config, generation, slot = read_config_file(bytes(updated))
        self.assertEqual((generation, slot), (1, 0))
        updated[HEADER_BYTES + 60] ^= 0x01
        with self.assertRaises(ImageConfigError):
            read_config_file(bytes(updated))

    def test_rejects_unknown_product_schema_and_fields(self) -> None:
        for field, value in (("product", "wrong"), ("schema_version", 2)):
            config = sample_config()
            config[field] = value
            with self.assertRaises(ImageConfigError):
                validate_config(config)
        config = sample_config()
        config["unexpected"] = True
        with self.assertRaises(ImageConfigError):
            validate_config(config)

    def test_utf8_ssid_and_utf16_secret_lengths_match_contract(self) -> None:
        config = sample_config()
        config["wifi"]["ssid"] = "中" * 10
        validate_config(config)
        config["wifi"]["ssid"] = "中" * 11
        with self.assertRaises(ImageConfigError):
            validate_config(config)
        config = sample_config()
        config["account"]["password"] = "😀" * 4
        validate_config(config)

    def test_static_ipv4_requires_same_subnet_and_valid_dns(self) -> None:
        config = sample_config()
        config["ipv4"] = {
            "mode": "static",
            "address": "192.168.10.20",
            "prefix": 24,
            "gateway": "192.168.10.1",
            "dns": ["1.1.1.1", "8.8.8.8"],
        }
        validate_config(config)
        config["ipv4"]["gateway"] = "192.168.11.1"
        with self.assertRaises(ImageConfigError):
            validate_config(config)

    def test_project_codec_cross_compatibility_when_repository_is_present(self) -> None:
        project_codec = SOURCE_ROOT.parents[2] / "核桃派软件源代码" / "scripts" / "image_config.py"
        if not project_codec.is_file():
            self.skipTest("独立源码副本中没有主工程交叉校验器")
        spec = importlib.util.spec_from_file_location("project_image_config", project_codec)
        assert spec is not None and spec.loader is not None
        module = importlib.util.module_from_spec(spec)
        spec.loader.exec_module(module)
        ours = create_config_file(copy.deepcopy(sample_config()))
        theirs = module.create_config_file(copy.deepcopy(sample_config()))
        self.assertEqual(module.read_config_file(ours)[0], read_config_file(theirs)[0])


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