import json
import os
import unittest

from components.sud import Sud

FIXTURES_DIR = os.path.join(os.path.dirname(__file__), '..', '..', 'utils', 'sud_fixtures')


def _load_fixture(name):
    with open(os.path.join(FIXTURES_DIR, name)) as f:
        return json.load(f)


class TestSudLoadRejectsMalformedDocs(unittest.TestCase):
    """Sud.load() wires in utils/sud_validate.py's validate_sud() so a
    malformed sud.json is refused (same False-returning contract as any
    other load() failure - see components/sud.py's own docstring) instead
    of parsing cleanly and only crashing much later, mid-run or during a
    forecast simulation, on the unguarded ramp['rate'] lookup."""

    def test_valid_doc_loads(self):
        sud = Sud()
        self.assertTrue(sud.load(_load_fixture('valid_multi_step.json')))
        self.assertEqual(sud.name, 'MultiStep')

    def test_missing_ramp_rate_is_refused(self):
        sud = Sud()
        self.assertFalse(sud.load(_load_fixture('missing_ramp_rate.json')))

    def test_wrong_type_ramp_rate_is_refused(self):
        sud = Sud()
        self.assertFalse(sud.load(_load_fixture('ramp_rate_wrong_type.json')))

    def test_empty_steps_is_refused(self):
        sud = Sud()
        self.assertFalse(sud.load(_load_fixture('empty_steps_list.json')))

    def test_failed_load_leaves_previous_schedule_untouched(self):
        sud = Sud()
        self.assertTrue(sud.load(_load_fixture('valid_multi_step.json')))
        self.assertFalse(sud.load(_load_fixture('missing_ramp_rate.json')))
        self.assertEqual(sud.name, 'MultiStep')
        self.assertEqual(len(sud.schedule), 3)


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