# Copyright (c) 2025 Patrick Motsch
# All rights reserved.
"""
Unit tests for `modules.shared.dateRange`.
Pure-Python, no DB / no API.
"""

from datetime import date, datetime, time as dtTime

import pytest
from fastapi import HTTPException

from modules.shared.dateRange import (
    daysInRange,
    isoDateRangeToLocalEpoch,
    parseIsoDate,
    parseIsoDateRange,
)


class TestParseIsoDate:
    def test_validIsoDate(self):
        assert parseIsoDate("2026-04-15", "dateFrom") == date(2026, 4, 15)

    def test_emptyStringRaises400(self):
        with pytest.raises(HTTPException) as exc:
            parseIsoDate("", "dateFrom")
        assert exc.value.status_code == 400
        assert "dateFrom" in exc.value.detail

    def test_invalidFormatRaises400(self):
        with pytest.raises(HTTPException) as exc:
            parseIsoDate("15.04.2026", "dateTo")
        assert exc.value.status_code == 400
        assert "dateTo" in exc.value.detail
        assert "15.04.2026" in exc.value.detail

    def test_nonStringRaises400(self):
        with pytest.raises(HTTPException) as exc:
            parseIsoDate(None, "dateFrom")  # type: ignore[arg-type]
        assert exc.value.status_code == 400


class TestParseIsoDateRange:
    def test_validRange(self):
        f, t = parseIsoDateRange("2026-04-01", "2026-04-15")
        assert f == date(2026, 4, 1)
        assert t == date(2026, 4, 15)

    def test_sameDayIsValid(self):
        f, t = parseIsoDateRange("2026-04-15", "2026-04-15")
        assert f == t

    def test_invertedRangeRaises400(self):
        with pytest.raises(HTTPException) as exc:
            parseIsoDateRange("2026-04-15", "2026-04-01")
        assert exc.value.status_code == 400
        assert "dateFrom must be <= dateTo" in exc.value.detail


class TestIsoDateRangeToLocalEpoch:
    def test_inclusiveEndOfDay(self):
        """`dateTo` boundary covers full last day (23:59:59.999999 local)."""
        fromTs, toTs = isoDateRangeToLocalEpoch("2026-04-15", "2026-04-15")
        startOfDay = datetime.combine(date(2026, 4, 15), dtTime.min).timestamp()
        endOfDay = datetime.combine(date(2026, 4, 15), dtTime.max).timestamp()
        assert fromTs == startOfDay
        assert toTs == endOfDay
        # Single-day range covers ~24h - 1 microsecond.
        assert (toTs - fromTs) > (24 * 3600 - 1)

    def test_multiDayRange(self):
        fromTs, toTs = isoDateRangeToLocalEpoch("2026-04-01", "2026-04-03")
        # Three local days, end-inclusive: ~3 * 86400 seconds (- 1us).
        assert 3 * 86400 - 1 < (toTs - fromTs) < 3 * 86400 + 1

    def test_invalidRaises400(self):
        with pytest.raises(HTTPException):
            isoDateRangeToLocalEpoch("not-a-date", "2026-04-03")


class TestDaysInRange:
    def test_singleDayIsOne(self):
        assert daysInRange("2026-04-15", "2026-04-15") == 1

    def test_threeDaysInclusive(self):
        assert daysInRange("2026-04-01", "2026-04-03") == 3

    def test_yearSpan(self):
        assert daysInRange("2026-01-01", "2026-12-31") == 365

    def test_invertedRangeRaises400(self):
        with pytest.raises(HTTPException):
            daysInRange("2026-04-15", "2026-04-01")