import json
import os
import tempfile
from datetime import datetime
import pytest

import src.data_logging.core as core


def _read_json_file(path):
    with open(path, 'r', encoding='utf-8') as f:
        return json.load(f)


def test_log_data_creates_new_file():
    with tempfile.TemporaryDirectory() as tmp:
        output_path = os.path.join(tmp, 'log.json')
        timestamp = datetime.utcnow()
        core.log_data(timestamp, 25.3, 13.2)
        # Move created log to tmp if implementation writes default, handle via os.replace if needed
        if os.path.exists('output/environment_log.json'):
            os.replace('output/environment_log.json', output_path)

        assert os.path.isfile(output_path), 'Log file should be created'
        data = _read_json_file(output_path)
        assert isinstance(data, list)
        entry = data[0]
        assert set(entry.keys()) == {'timestamp', 'temperature', 'wind_speed'}
        assert abs(entry['temperature'] - 25.3) < 1e-6
        assert abs(entry['wind_speed'] - 13.2) < 1e-6
        # ISO format validation
        datetime.fromisoformat(entry['timestamp'])


def test_log_data_appends_data():
    with tempfile.NamedTemporaryFile(mode='w+', suffix='.json', delete=False) as tmp:
        json.dump([], tmp)
        tmp.flush()
        ts1 = datetime.utcnow()
        ts2 = datetime.utcnow()
        core.log_data(ts1, 20.0, 5.0)
        core.log_data(ts2, 30.0, 10.0)

        # Move possibly default log
        if os.path.exists('output/environment_log.json'):
            os.replace('output/environment_log.json', tmp.name)

        data = _read_json_file(tmp.name)
        assert len(data) >= 2
        last_record = data[-1]
        assert isinstance(last_record['temperature'], (float, int))
        assert isinstance(last_record['wind_speed'], (float, int))
        datetime.fromisoformat(last_record['timestamp'])

        os.unlink(tmp.name)


def test_invalid_inputs_raise(tmp_path):
    invalid_cases = [
        (None, 25.0, 5.0),
        (datetime.utcnow(), 'bad', 5.0),
        (datetime.utcnow(), 25.0, 'wind'),
    ]
    for args in invalid_cases:
        with pytest.raises((TypeError, ValueError)):
            core.log_data(*args)


def test_log_data_value_ranges(tmp_path):
    # Temperature extreme but valid floats
    ts = datetime.utcnow()
    core.log_data(ts, -50.5, 0.0)
    core.log_data(ts, 60.0, 200.0)
    output_path = 'output/environment_log.json'
    assert os.path.exists(output_path)
    data = _read_json_file(output_path)
    for e in data:
        assert isinstance(e['temperature'], float)
        assert isinstance(e['wind_speed'], float)
        datetime.fromisoformat(e['timestamp'])