import errno
import importlib.util
from pathlib import Path
import tempfile
import unittest
from unittest.mock import patch

spec = importlib.util.spec_from_file_location("ec_agent_temperatures", Path(__file__).resolve().parents[1] / "ec_agent.py")
module = importlib.util.module_from_spec(spec)
spec.loader.exec_module(module)


class TemperatureTests(unittest.TestCase):
    def setUp(self):
        self.temp = tempfile.TemporaryDirectory()
        self.addCleanup(self.temp.cleanup)
        self.root = Path(self.temp.name)
        self.hwmon = self.root / "class"
        self.hwmon.mkdir()
        self.patch = patch.object(module, "HWMON_ROOT", self.hwmon)
        self.patch.start()
        self.addCleanup(self.patch.stop)
        self.agent = object.__new__(module.Agent)

    def chip(self, number, device, readings):
        physical = self.root / (device + str(number)) / "hwmon" / ("hwmon" + str(number))
        physical.mkdir(parents=True)
        (self.hwmon / physical.name).symlink_to(physical, target_is_directory=True)
        (physical / "name").write_text(device)
        for channel, label, value in readings:
            (physical / (channel + "_input")).write_text(str(value))
            if label is not None:
                (physical / (channel + "_label")).write_text(label)
        return physical

    def test_ec2_sensors_and_units_without_guessing_unknown_devices(self):
        self.chip(0, "nvme", [("temp1", "Composite", 50900), ("temp2", "Sensor 1", 50900)])
        self.chip(1, "pch_cometlake", [("temp1", None, 62000)])
        self.chip(2, "coretemp", [("temp1", "Package id 0", 65000), ("temp2", "Core 0", 63000)])
        self.chip(3, "iwlwifi_1", [("temp1", None, "unavailable")])
        samples = self.agent.temperatures()
        self.assertEqual([s["celsius"] for s in samples], [50.9, 50.9, 62.0, 65.0, 63.0])
        self.assertEqual([s["kind"] for s in samples], ["nvme", "nvme", "chipset", "cpu-package", "cpu-core"])
        self.assertEqual(len({s["id"] for s in samples}), len(samples))

    def test_fault_disabled_bad_value_and_enodata_do_not_lose_other_sensors(self):
        chip = self.chip(0, "coretemp", [("temp" + str(i), "Core " + str(i), value)
                         for i, value in enumerate([65000, 60000, "bad", 500000, 61000, 63000, 0], 1)])
        (chip / "temp1_fault").write_text("1")
        (chip / "temp2_enable").write_text("0")
        original = Path.read_text
        def read(path, *args, **kwargs):
            if path.name == "temp5_input":
                raise OSError(errno.ENODATA, "No data available")
            return original(path, *args, **kwargs)
        with patch.object(Path, "read_text", read):
            self.assertEqual([s["celsius"] for s in self.agent.temperatures()], [63.0, 0.0])

    def test_amd_keeps_physical_die_readings_and_excludes_control_offsets(self):
        self.chip(0, "k10temp", [("temp1", "Tctl", 85000), ("temp2", "Tdie", 65000), ("temp3", "Tccd1", 64000)])
        self.assertEqual([s["label"] for s in self.agent.temperatures()], ["Tdie", "Tccd1"])

    def test_sensor_identity_survives_hwmon_renumbering_and_separates_drives(self):
        physical = self.chip(1, "nvme", [("temp1", "Composite", 50000)])
        self.chip(2, "nvme", [("temp1", "Composite", 51000)])
        before = {s["celsius"]: s["id"] for s in self.agent.temperatures()}
        renamed = physical.with_name("hwmon9")
        physical.rename(renamed)
        (self.hwmon / "hwmon1").unlink()
        (self.hwmon / "hwmon9").symlink_to(renamed, target_is_directory=True)
        self.assertEqual(before, {s["celsius"]: s["id"] for s in self.agent.temperatures()})
        self.assertEqual(len(set(before.values())), 2)

    def test_missing_hwmon_and_disappearing_devices_are_optional(self):
        self.assertEqual(self.agent.temperatures(), [])
        (self.hwmon / "hwmon0").symlink_to(self.root / "missing")
        self.assertEqual(self.agent.temperatures(), [])
        with patch.object(Path, "glob", side_effect=PermissionError()):
            self.assertEqual(self.agent.temperatures(), [])

    def test_direct_hwmon_child_keeps_identity_when_renumbered(self):
        physical = self.chip(1, "nvme", [("temp1", "Composite", 50000)])
        direct = physical.parent.parent / "hwmon8"
        physical.rename(direct)
        (self.hwmon / "hwmon1").unlink()
        (self.hwmon / "hwmon8").symlink_to(direct, target_is_directory=True)
        before = self.agent.temperatures()[0]["id"]
        renamed = direct.with_name("hwmon9")
        direct.rename(renamed)
        (self.hwmon / "hwmon8").unlink()
        (self.hwmon / "hwmon9").symlink_to(renamed, target_is_directory=True)
        self.assertEqual(self.agent.temperatures()[0]["id"], before)

    def test_inventory_size_is_bounded(self):
        self.chip(0, "coretemp", [("temp" + str(i), "Core " + str(i), 65000) for i in range(1, 200)])
        self.assertEqual(len(self.agent.temperatures()), 128)