"""Tests for WeatherSatDecoder class.

Covers WeatherSatDecoder methods, subprocess management, progress callbacks,
and image handling.
"""

from __future__ import annotations

import os
import tempfile
import threading
import time
from datetime import datetime, timezone
from pathlib import Path
from unittest.mock import patch, MagicMock, call, mock_open
import pytest

from utils.weather_sat import (
    WeatherSatDecoder,
    WeatherSatImage,
    CaptureProgress,
    WEATHER_SATELLITES,
    get_weather_sat_decoder,
    is_weather_sat_available,
)


class TestWeatherSatDecoder:
    """Tests for WeatherSatDecoder class."""

    def test_decoder_initialization(self):
        """Decoder should initialize with default output directory."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            decoder = WeatherSatDecoder()
            assert decoder.is_running is False
            assert decoder.decoder_available == 'satdump'
            assert decoder.current_satellite == ''
            assert decoder.current_frequency == 0.0

    def test_decoder_initialization_no_satdump(self):
        """Decoder should detect when SatDump is unavailable."""
        with patch('shutil.which', return_value=None):
            decoder = WeatherSatDecoder()
            assert decoder.decoder_available is None

    def test_decoder_custom_output_dir(self):
        """Decoder should accept custom output directory."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            custom_dir = '/tmp/custom_output'
            decoder = WeatherSatDecoder(output_dir=custom_dir)
            assert decoder._output_dir == Path(custom_dir)

    def test_set_callback(self):
        """Decoder should accept progress callback."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            decoder = WeatherSatDecoder()
            callback = MagicMock()
            decoder.set_callback(callback)
            assert decoder._callback == callback

    def test_set_on_complete(self):
        """Decoder should accept on_complete callback."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            decoder = WeatherSatDecoder()
            callback = MagicMock()
            decoder.set_on_complete(callback)
            assert decoder._on_complete_callback == callback

    def test_start_no_decoder(self):
        """start() should fail when no decoder available."""
        with patch('shutil.which', return_value=None):
            decoder = WeatherSatDecoder()
            callback = MagicMock()
            decoder.set_callback(callback)

            success, error_msg = decoder.start(satellite='NOAA-18', device_index=0, gain=40.0)

            assert success is False
            assert error_msg is not None
            callback.assert_called()
            progress = callback.call_args[0][0]
            assert progress.status == 'error'
            assert 'SatDump' in progress.message

    def test_start_invalid_satellite(self):
        """start() should fail with invalid satellite."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            decoder = WeatherSatDecoder()
            callback = MagicMock()
            decoder.set_callback(callback)

            success, error_msg = decoder.start(satellite='FAKE-SAT', device_index=0, gain=40.0)

            assert success is False
            callback.assert_called()
            progress = callback.call_args[0][0]
            assert progress.status == 'error'
            assert 'Unknown satellite' in progress.message

    @patch('subprocess.Popen')
    @patch('pty.openpty')
    @patch('utils.weather_sat.register_process')
    def test_start_success(self, mock_register, mock_pty, mock_popen):
        """start() should successfully start SatDump."""
        with patch('shutil.which', return_value='/usr/bin/satdump'), \
             patch('utils.weather_sat.WeatherSatDecoder._resolve_device_id', return_value='0'):

            mock_pty.return_value = (10, 11)
            mock_process = MagicMock()
            mock_process.poll.return_value = None
            mock_popen.return_value = mock_process

            decoder = WeatherSatDecoder()
            callback = MagicMock()
            decoder.set_callback(callback)

            success, error_msg = decoder.start(
                satellite='NOAA-18',
                device_index=0,
                gain=40.0,
                bias_t=True,
            )

            assert success is True
            assert error_msg is None
            assert decoder.is_running is True
            assert decoder.current_satellite == 'NOAA-18'
            assert decoder.current_frequency == 137.9125
            assert decoder.current_mode == 'APT'
            assert decoder.device_index == 0

            mock_popen.assert_called_once()
            cmd = mock_popen.call_args[0][0]
            assert cmd[0] == 'satdump'
            assert 'live' in cmd
            assert 'noaa_apt' in cmd
            assert '--bias' in cmd

    @patch('subprocess.Popen')
    @patch('pty.openpty')
    def test_start_already_running(self, mock_pty, mock_popen):
        """start() should return True when already running."""
        with patch('shutil.which', return_value='/usr/bin/satdump'), \
             patch('utils.weather_sat.WeatherSatDecoder._resolve_device_id', return_value='0'):
            decoder = WeatherSatDecoder()
            decoder._running = True

            success, error_msg = decoder.start(satellite='NOAA-18', device_index=0, gain=40.0)

            assert success is True
            assert error_msg is None
            mock_popen.assert_not_called()

    @patch('subprocess.Popen')
    @patch('pty.openpty')
    def test_start_exception_handling(self, mock_pty, mock_popen):
        """start() should handle exceptions gracefully."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            mock_pty.return_value = (10, 11)
            mock_popen.side_effect = OSError('Device not found')

            decoder = WeatherSatDecoder()
            callback = MagicMock()
            decoder.set_callback(callback)

            success, error_msg = decoder.start(satellite='NOAA-18', device_index=0, gain=40.0)

            assert success is False
            assert error_msg is not None
            assert decoder.is_running is False
            callback.assert_called()
            progress = callback.call_args[0][0]
            assert progress.status == 'error'

    def test_start_from_file_no_decoder(self):
        """start_from_file() should fail when no decoder available."""
        with patch('shutil.which', return_value=None):
            decoder = WeatherSatDecoder()
            callback = MagicMock()
            decoder.set_callback(callback)

            success, error_msg = decoder.start_from_file(
                satellite='NOAA-18',
                input_file='data/test.wav',
            )

            assert success is False
            assert error_msg is not None
            callback.assert_called()

    @patch('subprocess.Popen')
    @patch('pty.openpty')
    @patch('pathlib.Path.is_file', return_value=True)
    @patch('pathlib.Path.resolve')
    def test_start_from_file_success(self, mock_resolve, mock_is_file, mock_pty, mock_popen):
        """start_from_file() should successfully decode from file."""
        with patch('shutil.which', return_value='/usr/bin/satdump'), \
             patch('utils.weather_sat.register_process'):

            # Mock path resolution
            mock_path = MagicMock()
            mock_path.is_relative_to.return_value = True
            mock_path.suffix = '.wav'
            mock_resolve.return_value = mock_path

            mock_pty.return_value = (10, 11)
            mock_process = MagicMock()
            mock_process.poll.return_value = None  # Process still running
            mock_popen.return_value = mock_process

            decoder = WeatherSatDecoder()
            callback = MagicMock()
            decoder.set_callback(callback)

            success, error_msg = decoder.start_from_file(
                satellite='NOAA-18',
                input_file='data/test.wav',
                sample_rate=1000000,
            )

            assert success is True
            assert error_msg is None
            assert decoder.is_running is True
            assert decoder.current_satellite == 'NOAA-18'

            mock_popen.assert_called_once()
            cmd = mock_popen.call_args[0][0]
            assert cmd[0] == 'satdump'
            assert 'noaa_apt' in cmd
            assert 'audio_wav' in cmd
            assert '--samplerate' in cmd

    @patch('pathlib.Path.resolve')
    def test_start_from_file_path_traversal(self, mock_resolve):
        """start_from_file() should block path traversal."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            # Mock path outside allowed directory
            mock_path = MagicMock()
            mock_path.is_relative_to.return_value = False
            mock_resolve.return_value = mock_path

            decoder = WeatherSatDecoder()
            callback = MagicMock()
            decoder.set_callback(callback)

            success, error_msg = decoder.start_from_file(
                satellite='NOAA-18',
                input_file='/etc/passwd',
            )

            assert success is False
            callback.assert_called()
            progress = callback.call_args[0][0]
            assert 'data/ directory' in progress.message

    @patch('pathlib.Path.is_file', return_value=False)
    @patch('pathlib.Path.resolve')
    def test_start_from_file_not_found(self, mock_resolve, mock_is_file):
        """start_from_file() should fail when file not found."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            mock_path = MagicMock()
            mock_path.is_relative_to.return_value = True
            mock_resolve.return_value = mock_path

            decoder = WeatherSatDecoder()
            callback = MagicMock()
            decoder.set_callback(callback)

            success, error_msg = decoder.start_from_file(
                satellite='NOAA-18',
                input_file='data/missing.wav',
            )

            assert success is False
            callback.assert_called()
            progress = callback.call_args[0][0]
            assert 'not found' in progress.message.lower()

    def test_stop_not_running(self):
        """stop() should be safe when not running."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            decoder = WeatherSatDecoder()
            decoder.stop()  # Should not raise

    @patch('utils.weather_sat.safe_terminate')
    def test_stop_running(self, mock_terminate):
        """stop() should terminate process."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            decoder = WeatherSatDecoder()
            mock_process = MagicMock()
            decoder._process = mock_process
            decoder._running = True
            decoder._pty_master_fd = 10

            with patch('os.close') as mock_close:
                decoder.stop()

            assert decoder._running is False
            mock_terminate.assert_called_once_with(mock_process)
            mock_close.assert_called_once_with(10)

    def test_get_images_empty(self):
        """get_images() should return empty list initially."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            decoder = WeatherSatDecoder()
            images = decoder.get_images()
            assert images == []

    @patch('pathlib.Path.glob')
    @patch('pathlib.Path.stat')
    def test_get_images_scans_directory(self, mock_stat, mock_glob):
        """get_images() should scan output directory."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            decoder = WeatherSatDecoder()

            # Mock image files
            mock_file = MagicMock()
            mock_file.name = 'NOAA-18_test.png'
            mock_file.stat.return_value.st_size = 10000
            mock_file.stat.return_value.st_mtime = time.time()
            mock_glob.return_value = [mock_file]

            images = decoder.get_images()

            assert len(images) == 1
            assert images[0].filename == 'NOAA-18_test.png'
            assert images[0].satellite == 'NOAA-18'

    def test_delete_image_success(self):
        """delete_image() should delete file."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            decoder = WeatherSatDecoder()

            with patch('pathlib.Path.exists', return_value=True), \
                 patch('pathlib.Path.unlink') as mock_unlink:

                result = decoder.delete_image('test.png')

                assert result is True
                mock_unlink.assert_called_once()

    def test_delete_image_not_found(self):
        """delete_image() should return False for non-existent file."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            decoder = WeatherSatDecoder()

            with patch('pathlib.Path.exists', return_value=False):
                result = decoder.delete_image('missing.png')

                assert result is False

    def test_delete_all_images(self):
        """delete_all_images() should delete all images."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            decoder = WeatherSatDecoder()

            mock_files = [MagicMock() for _ in range(3)]
            with patch('pathlib.Path.glob', return_value=mock_files):
                count = decoder.delete_all_images()

                assert count == 3
                for f in mock_files:
                    f.unlink.assert_called_once()

    def test_get_status_idle(self):
        """get_status() should return idle status."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            decoder = WeatherSatDecoder()
            status = decoder.get_status()

            assert status['available'] is True
            assert status['decoder'] == 'satdump'
            assert status['running'] is False
            assert status['satellite'] == ''

    def test_get_status_running(self):
        """get_status() should return running status."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            decoder = WeatherSatDecoder()
            decoder._running = True
            decoder._current_satellite = 'NOAA-18'
            decoder._current_frequency = 137.9125
            decoder._current_mode = 'APT'
            decoder._capture_start_time = time.time() - 60

            status = decoder.get_status()

            assert status['running'] is True
            assert status['satellite'] == 'NOAA-18'
            assert status['frequency'] == 137.9125
            assert status['mode'] == 'APT'
            assert status['elapsed_seconds'] >= 60

    def test_classify_log_type_error(self):
        """_classify_log_type() should detect errors."""
        assert WeatherSatDecoder._classify_log_type('(E) Error occurred') == 'error'
        assert WeatherSatDecoder._classify_log_type('Failed to open device') == 'error'

    def test_classify_log_type_progress(self):
        """_classify_log_type() should detect progress."""
        assert WeatherSatDecoder._classify_log_type('Progress: 50%') == 'progress'

    def test_classify_log_type_save(self):
        """_classify_log_type() should detect save events."""
        assert WeatherSatDecoder._classify_log_type('Saved image: test.png') == 'save'
        assert WeatherSatDecoder._classify_log_type('Writing output file') == 'save'

    def test_classify_log_type_signal(self):
        """_classify_log_type() should detect signal events."""
        assert WeatherSatDecoder._classify_log_type('Signal detected') == 'signal'
        assert WeatherSatDecoder._classify_log_type('Lock acquired') == 'signal'

    def test_classify_log_type_warning(self):
        """_classify_log_type() should detect warnings."""
        assert WeatherSatDecoder._classify_log_type('(W) Low signal quality') == 'warning'

    def test_classify_log_type_debug(self):
        """_classify_log_type() should detect debug messages."""
        assert WeatherSatDecoder._classify_log_type('(D) Debug info') == 'debug'

    @patch('subprocess.run')
    def test_resolve_device_id_success(self, mock_run):
        """_resolve_device_id() should extract serial from rtl_test."""
        mock_result = MagicMock()
        mock_result.stdout = 'Found 1 device(s):\n  0: RTLSDRBlog, SN: 00004000'
        mock_result.stderr = ''
        mock_run.return_value = mock_result

        serial = WeatherSatDecoder._resolve_device_id(0)

        assert serial == '00004000'
        mock_run.assert_called_once()

    @patch('subprocess.run')
    def test_resolve_device_id_fallback(self, mock_run):
        """_resolve_device_id() should return None when no serial found."""
        mock_run.side_effect = FileNotFoundError

        serial = WeatherSatDecoder._resolve_device_id(0)

        assert serial is None

    def test_parse_product_name_rgb(self):
        """_parse_product_name() should identify RGB composite."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            decoder = WeatherSatDecoder()
            product = decoder._parse_product_name(Path('/tmp/output/rgb_composite.png'))
            assert product == 'RGB Composite'

    def test_parse_product_name_thermal(self):
        """_parse_product_name() should identify thermal imagery."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            decoder = WeatherSatDecoder()
            product = decoder._parse_product_name(Path('/tmp/output/thermal_image.png'))
            assert product == 'Thermal'

    def test_parse_product_name_channel(self):
        """_parse_product_name() should identify channel images."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            decoder = WeatherSatDecoder()
            product = decoder._parse_product_name(Path('/tmp/output/channel_3.png'))
            assert product == 'Channel 3'

    def test_parse_product_name_unknown(self):
        """_parse_product_name() should return stem for unknown products."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            decoder = WeatherSatDecoder()
            product = decoder._parse_product_name(Path('/tmp/output/unknown_image.png'))
            assert product == 'unknown_image'

    def test_emit_progress(self):
        """_emit_progress() should call callback."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            decoder = WeatherSatDecoder()
            callback = MagicMock()
            decoder.set_callback(callback)

            progress = CaptureProgress(status='capturing', message='Test')
            decoder._emit_progress(progress)

            callback.assert_called_once_with(progress)

    def test_emit_progress_no_callback(self):
        """_emit_progress() should handle missing callback."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            decoder = WeatherSatDecoder()
            progress = CaptureProgress(status='capturing', message='Test')
            decoder._emit_progress(progress)  # Should not raise

    def test_emit_progress_callback_exception(self):
        """_emit_progress() should handle callback exceptions."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            decoder = WeatherSatDecoder()
            callback = MagicMock(side_effect=Exception('Callback error'))
            decoder.set_callback(callback)

            progress = CaptureProgress(status='capturing', message='Test')
            decoder._emit_progress(progress)  # Should not raise


class TestWeatherSatImage:
    """Tests for WeatherSatImage dataclass."""

    def test_to_dict(self):
        """WeatherSatImage.to_dict() should serialize correctly."""
        image = WeatherSatImage(
            filename='test.png',
            path=Path('/tmp/test.png'),
            satellite='NOAA-18',
            mode='APT',
            timestamp=datetime(2024, 1, 1, 12, 0, 0, tzinfo=timezone.utc),
            frequency=137.9125,
            size_bytes=12345,
            product='RGB Composite',
        )

        data = image.to_dict()

        assert data['filename'] == 'test.png'
        assert data['satellite'] == 'NOAA-18'
        assert data['mode'] == 'APT'
        assert data['timestamp'] == '2024-01-01T12:00:00+00:00'
        assert data['frequency'] == 137.9125
        assert data['size_bytes'] == 12345
        assert data['product'] == 'RGB Composite'
        assert data['url'] == '/weather-sat/images/test.png'


class TestCaptureProgress:
    """Tests for CaptureProgress dataclass."""

    def test_to_dict_minimal(self):
        """CaptureProgress.to_dict() with minimal fields."""
        progress = CaptureProgress(status='idle')
        data = progress.to_dict()

        assert data['type'] == 'weather_sat_progress'
        assert data['status'] == 'idle'
        assert data['satellite'] == ''
        assert data['message'] == ''
        assert data['progress'] == 0

    def test_to_dict_complete(self):
        """CaptureProgress.to_dict() with all fields."""
        image = WeatherSatImage(
            filename='test.png',
            path=Path('/tmp/test.png'),
            satellite='NOAA-18',
            mode='APT',
            timestamp=datetime.now(timezone.utc),
            frequency=137.9125,
        )

        progress = CaptureProgress(
            status='complete',
            satellite='NOAA-18',
            frequency=137.9125,
            mode='APT',
            message='Capture complete',
            progress_percent=100,
            elapsed_seconds=600,
            image=image,
            log_type='info',
            capture_phase='complete',
        )

        data = progress.to_dict()

        assert data['status'] == 'complete'
        assert data['satellite'] == 'NOAA-18'
        assert data['frequency'] == 137.9125
        assert data['mode'] == 'APT'
        assert data['message'] == 'Capture complete'
        assert data['progress'] == 100
        assert data['elapsed_seconds'] == 600
        assert 'image' in data
        assert data['log_type'] == 'info'
        assert data['capture_phase'] == 'complete'


class TestGlobalFunctions:
    """Tests for global utility functions."""

    def test_get_weather_sat_decoder_singleton(self):
        """get_weather_sat_decoder() should return singleton."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            import utils.weather_sat as mod
            old = mod._decoder
            mod._decoder = None

            try:
                decoder1 = get_weather_sat_decoder()
                decoder2 = get_weather_sat_decoder()

                assert decoder1 is decoder2
            finally:
                mod._decoder = old

    def test_is_weather_sat_available_true(self):
        """is_weather_sat_available() should return True when available."""
        with patch('shutil.which', return_value='/usr/bin/satdump'):
            import utils.weather_sat as mod
            old = mod._decoder
            mod._decoder = None

            try:
                assert is_weather_sat_available() is True
            finally:
                mod._decoder = old

    def test_is_weather_sat_available_false(self):
        """is_weather_sat_available() should return False when unavailable."""
        with patch('shutil.which', return_value=None):
            import utils.weather_sat as mod
            old = mod._decoder
            mod._decoder = None

            try:
                assert is_weather_sat_available() is False
            finally:
                mod._decoder = old


class TestWeatherSatellitesConstant:
    """Tests for WEATHER_SATELLITES constant."""

    def test_weather_satellites_structure(self):
        """WEATHER_SATELLITES should have correct structure."""
        assert 'NOAA-18' in WEATHER_SATELLITES
        sat = WEATHER_SATELLITES['NOAA-18']

        assert 'name' in sat
        assert 'frequency' in sat
        assert 'mode' in sat
        assert 'pipeline' in sat
        assert 'tle_key' in sat
        assert 'description' in sat
        assert 'active' in sat

    def test_noaa_satellites(self):
        """NOAA satellites should have correct frequencies."""
        assert WEATHER_SATELLITES['NOAA-15']['frequency'] == 137.620
        assert WEATHER_SATELLITES['NOAA-18']['frequency'] == 137.9125
        assert WEATHER_SATELLITES['NOAA-19']['frequency'] == 137.100

    def test_meteor_satellite(self):
        """Meteor satellite should use LRPT mode."""
        meteor = WEATHER_SATELLITES['METEOR-M2-3']
        assert meteor['mode'] == 'LRPT'
        assert meteor['frequency'] == 137.900
        assert meteor['pipeline'] == 'meteor_m2-x_lrpt'