"""Tests for SystemHealthMonitor pure methods — no external processes or filesystem."""
import sys
import os

import pytest

sys.path.insert(0, os.path.dirname(os.path.dirname(__file__)))

from unittest.mock import patch  # noqa: E402
from hwmonDaemon import SystemHealthMonitor  # noqa: E402


@pytest.fixture(scope='module')
def monitor():
    """Create a minimal monitor instance with all external side-effects patched out."""
    with patch.object(SystemHealthMonitor, 'load_env_config'), \
         patch.object(SystemHealthMonitor, '_check_tool_availability', return_value={}), \
         patch('os.makedirs'):
        return SystemHealthMonitor(dry_run=True)


# ── _format_bytes_human ──────────────────────────────────────────────────────

class TestFormatBytesHuman:
    def test_bytes(self, monitor):
        assert monitor._format_bytes_human(512) == '512.0 B'

    def test_kilobytes(self, monitor):
        assert monitor._format_bytes_human(1024) == '1.0 KB'

    def test_megabytes(self, monitor):
        assert monitor._format_bytes_human(1024 ** 2) == '1.0 MB'

    def test_gigabytes(self, monitor):
        assert monitor._format_bytes_human(1024 ** 3) == '1.0 GB'

    def test_terabytes(self, monitor):
        assert monitor._format_bytes_human(1024 ** 4) == '1.0 TB'

    def test_fractional(self, monitor):
        assert monitor._format_bytes_human(1536) == '1.5 KB'

    def test_zero(self, monitor):
        assert monitor._format_bytes_human(0) == '0.0 B'


# ── _parse_size ───────────────────────────────────────────────────────────────

class TestParseSize:
    def test_gigabytes(self, monitor):
        result = monitor._parse_size('15.7G')
        assert abs(result - 15.7 * 1024**3) < 1

    def test_terabytes(self, monitor):
        result = monitor._parse_size('21.8T')
        assert abs(result - 21.8 * 1024**4) < 1

    def test_megabytes(self, monitor):
        result = monitor._parse_size('512M')
        assert result == 512 * 1024**2

    def test_kilobytes(self, monitor):
        result = monitor._parse_size('100K')
        assert result == 100 * 1024

    def test_bytes(self, monitor):
        result = monitor._parse_size('100B')
        assert result == 100

    def test_invalid_returns_zero(self, monitor):
        assert monitor._parse_size('notasize') == 0.0

    def test_non_string_returns_zero(self, monitor):
        assert monitor._parse_size(None) == 0.0
        assert monitor._parse_size(42) == 0.0


# ── _parse_smart_value ────────────────────────────────────────────────────────

class TestParseSmartValue:
    def test_plain_integer(self, monitor):
        assert monitor._parse_smart_value('42') == 42

    def test_temperature_with_celsius(self, monitor):
        assert monitor._parse_smart_value('38 °C') == 38

    def test_time_format(self, monitor):
        assert monitor._parse_smart_value('15589h+17m+33.939s') == 15589

    def test_hex_value(self, monitor):
        assert monitor._parse_smart_value('0x0a') == 10

    def test_invalid_returns_zero(self, monitor):
        assert monitor._parse_smart_value('not_a_number') == 0


# ── _detect_manufacturer ──────────────────────────────────────────────────────

class TestDetectManufacturer:
    def test_western_digital(self, monitor):
        assert monitor._detect_manufacturer('WDC WD40EFRX') == 'Western Digital'

    def test_hgst(self, monitor):
        assert monitor._detect_manufacturer('HGST HUH728080ALE604') == 'Western Digital'

    def test_seagate(self, monitor):
        assert monitor._detect_manufacturer('ST4000DM004') == 'Seagate'

    def test_samsung(self, monitor):
        assert monitor._detect_manufacturer('Samsung SSD 870 EVO') == 'Samsung'

    def test_intel(self, monitor):
        assert monitor._detect_manufacturer('INTEL SSDSC2KB480G8') == 'Intel'

    def test_micron(self, monitor):
        assert monitor._detect_manufacturer('Crucial CT500MX500SSD1') == 'Micron'

    def test_toshiba(self, monitor):
        assert monitor._detect_manufacturer('TOSHIBA MG06ACA10TE') == 'Toshiba'

    def test_unknown(self, monitor):
        assert monitor._detect_manufacturer('GENERICDRIVE XYZ') == 'Unknown'

    def test_empty_model(self, monitor):
        assert monitor._detect_manufacturer('') == 'Unknown'

    def test_none_model(self, monitor):
        assert monitor._detect_manufacturer(None) == 'Unknown'


# ── _check_thermal_health ─────────────────────────────────────────────────────

class TestCheckThermalHealth:
    def test_hdd_ok_temperature(self, monitor):
        issues = monitor._check_thermal_health('sda', 45, 'HDD')
        assert issues == []

    def test_hdd_info_temperature(self, monitor):
        issues = monitor._check_thermal_health('sda', 62, 'HDD')
        assert len(issues) == 1
        assert 'INFO' in issues[0]

    def test_hdd_warning_temperature(self, monitor):
        issues = monitor._check_thermal_health('sda', 66, 'HDD')
        assert len(issues) == 1
        assert 'WARNING' in issues[0]

    def test_hdd_critical_temperature(self, monitor):
        issues = monitor._check_thermal_health('sda', 76, 'HDD')
        assert len(issues) == 1
        assert 'CRITICAL' in issues[0]

    def test_ssd_has_higher_warning_threshold(self, monitor):
        # HDD warning=65°C, SSD warning=70°C; at 67°C:
        # HDD → WARNING, SSD → INFO (above optimal_max=65 but below warning=70)
        issues_hdd = monitor._check_thermal_health('sda', 67, 'HDD')
        issues_ssd = monitor._check_thermal_health('sda', 67, 'SSD')
        assert any('WARNING' in i for i in issues_hdd)
        assert not any('WARNING' in i for i in issues_ssd)
        assert any('INFO' in i for i in issues_ssd)

    def test_none_temperature_returns_empty(self, monitor):
        issues = monitor._check_thermal_health('sda', None, 'HDD')
        assert issues == []


# ── _is_excluded_mount ────────────────────────────────────────────────────────

class TestIsExcludedMount:
    def test_exact_excluded_mount(self, monitor):
        assert monitor._is_excluded_mount('/media') is True

    def test_pattern_excluded(self, monitor):
        assert monitor._is_excluded_mount('/media/external') is True

    def test_downloads_excluded(self, monitor):
        assert monitor._is_excluded_mount('/mnt/data/downloads') is True

    def test_normal_mount_not_excluded(self, monitor):
        assert monitor._is_excluded_mount('/') is False
        assert monitor._is_excluded_mount('/var') is False
        assert monitor._is_excluded_mount('/mnt/ceph') is False


# ── _is_new_drive ─────────────────────────────────────────────────────────────

class TestIsNewDrive:
    def test_brand_new_drive(self, monitor):
        assert monitor._is_new_drive(0) is True

    def test_one_hour_drive(self, monitor):
        assert monitor._is_new_drive(1) is True

    def test_under_threshold(self, monitor):
        assert monitor._is_new_drive(719) is True

    def test_at_threshold_is_not_new(self, monitor):
        assert monitor._is_new_drive(720) is False

    def test_old_drive(self, monitor):
        assert monitor._is_new_drive(50000) is False


# ── _is_physical_disk ────────────────────────────────────────────────────────

class TestIsPhysicalDisk:
    def test_real_sata_disk(self, monitor):
        # /dev/sda should pass (no exclusion pattern matches)
        # Note: _is_physical_disk also checks os.path.exists and reads sysfs,
        # but the exclusion logic runs first and can return False early.
        # We test the exclusion cases which are pure.
        assert monitor._is_physical_disk('/dev/mapper/data') is False

    def test_device_mapper_excluded(self, monitor):
        assert monitor._is_physical_disk('/dev/dm-0') is False

    def test_loop_device_excluded(self, monitor):
        assert monitor._is_physical_disk('/dev/loop0') is False

    def test_partition_excluded(self, monitor):
        assert monitor._is_physical_disk('/dev/sda1') is False

    def test_rbd_excluded(self, monitor):
        assert monitor._is_physical_disk('/dev/rbd0') is False