import datetime
import re

import pytest


@pytest.fixture
def instructor(dev_client):
    dev_client.post("/dev/launch/dev-instructor")
    return dev_client


def test_generate_range_creates_weekday_dates(instructor):
    # A fixed two-week window well in the future, Mon/Wed.
    resp = instructor.post(
        "/instructor/schedule/generate",
        data={
            "start": "2027-01-04",
            "end": "2027-01-15",
            "weekday": ["0", "2"],
        },
        follow_redirects=True,
    )
    page = resp.get_data(as_text=True)
    for expected in ["Jan 4", "Jan 6", "Jan 11", "Jan 13"]:
        assert expected in page
    assert "Jan 5" not in page

    # Re-generating the same range adds nothing new.
    resp = instructor.post(
        "/instructor/schedule/generate",
        data={"start": "2027-01-04", "end": "2027-01-15", "weekday": ["0"]},
        follow_redirects=True,
    )
    assert resp.get_data(as_text=True).count("Jan 4") == 1


def test_generate_rejects_bad_input(instructor):
    resp = instructor.post(
        "/instructor/schedule/generate",
        data={"start": "2027-01-15", "end": "2027-01-04", "weekday": ["0"]},
    )
    assert resp.status_code == 400
    resp = instructor.post(
        "/instructor/schedule/generate",
        data={"start": "2027-01-04", "end": "2027-01-15"},
    )
    assert resp.status_code == 400


def test_add_and_delete_single_day(instructor):
    resp = instructor.post(
        "/instructor/schedule/add",
        data={"date": "2027-03-01"},
        follow_redirects=True,
    )
    page = resp.get_data(as_text=True)
    assert "Mar 1, 2027" in page

    # Find the delete form id adjacent to the date row.
    rows = re.findall(
        r"<td[^>]*>\s*(\w{3} \w{3} \d+, \d{4})\s*</td>.*?/instructor/schedule/(\d+)/delete",
        page,
        re.S,
    )
    ids = {label: did for label, did in rows}
    day_id = ids["Mon Mar 1, 2027"]

    resp = instructor.post(
        f"/instructor/schedule/{day_id}/delete", follow_redirects=True
    )
    assert "Mar 1, 2027" not in resp.get_data(as_text=True)


def test_schedule_requires_instructor(dev_client):
    dev_client.post("/dev/launch/dev-instructor")  # create course
    dev_client.post("/dev/launch/dev-student-1")
    assert dev_client.get("/instructor/schedule").status_code == 403