import unittest
from datetime import datetime, timezone

from scheduler.db_utils import (
    build_group_power_intent_body,
    compute_group_power_intent_basis,
    compute_group_power_intent_fingerprint,
)


class PowerIntentUtilsTests(unittest.TestCase):
    def test_no_events_results_in_off(self):
        now = datetime(2026, 3, 31, 10, 0, 0, tzinfo=timezone.utc)
        basis = compute_group_power_intent_basis(events=[], group_id=7, now_utc=now)

        self.assertEqual(basis["group_id"], 7)
        self.assertEqual(basis["desired_state"], "off")
        self.assertEqual(basis["reason"], "no_active_event")
        self.assertIsNone(basis["event_window_start"])
        self.assertIsNone(basis["event_window_end"])

    def test_active_event_results_in_on(self):
        now = datetime(2026, 3, 31, 10, 5, 0, tzinfo=timezone.utc)
        events = [
            {
                "id": 101,
                "group_id": 2,
                "start": "2026-03-31T10:00:00+00:00",
                "end": "2026-03-31T10:30:00+00:00",
            }
        ]

        basis = compute_group_power_intent_basis(events=events, group_id=2, now_utc=now)

        self.assertEqual(basis["desired_state"], "on")
        self.assertEqual(basis["reason"], "active_event")
        self.assertEqual(basis["event_window_start"], "2026-03-31T10:00:00Z")
        self.assertEqual(basis["event_window_end"], "2026-03-31T10:30:00Z")
        self.assertEqual(basis["active_event_ids"], [101])

    def test_adjacent_events_are_merged_without_off_blip(self):
        now = datetime(2026, 3, 31, 10, 30, 0, tzinfo=timezone.utc)
        events = [
            {
                "id": 1,
                "group_id": 3,
                "start": "2026-03-31T10:00:00+00:00",
                "end": "2026-03-31T10:30:00+00:00",
            },
            {
                "id": 2,
                "group_id": 3,
                "start": "2026-03-31T10:30:00+00:00",
                "end": "2026-03-31T11:00:00+00:00",
            },
        ]

        basis = compute_group_power_intent_basis(events=events, group_id=3, now_utc=now)

        self.assertEqual(basis["desired_state"], "on")
        self.assertEqual(basis["event_window_start"], "2026-03-31T10:00:00Z")
        self.assertEqual(basis["event_window_end"], "2026-03-31T11:00:00Z")

    def test_true_gap_results_in_off(self):
        now = datetime(2026, 3, 31, 10, 31, 0, tzinfo=timezone.utc)
        events = [
            {
                "id": 1,
                "group_id": 4,
                "start": "2026-03-31T10:00:00+00:00",
                "end": "2026-03-31T10:30:00+00:00",
            },
            {
                "id": 2,
                "group_id": 4,
                "start": "2026-03-31T10:35:00+00:00",
                "end": "2026-03-31T11:00:00+00:00",
            },
        ]

        basis = compute_group_power_intent_basis(events=events, group_id=4, now_utc=now)

        self.assertEqual(basis["desired_state"], "off")
        self.assertEqual(basis["reason"], "no_active_event")

    def test_fingerprint_is_stable_for_same_semantics(self):
        basis = {
            "schema_version": "1.0",
            "group_id": 9,
            "desired_state": "on",
            "reason": "active_event",
            "event_window_start": "2026-03-31T10:00:00Z",
            "event_window_end": "2026-03-31T10:30:00Z",
            "active_event_ids": [12, 7],
        }
        body_a = build_group_power_intent_body(basis, poll_interval_sec=15)
        body_b = build_group_power_intent_body(basis, poll_interval_sec=15)

        fingerprint_a = compute_group_power_intent_fingerprint(body_a)
        fingerprint_b = compute_group_power_intent_fingerprint(body_b)

        self.assertEqual(fingerprint_a, fingerprint_b)


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