from pathlib import Path
import sys

from sqlalchemy import text

ROOT = Path(__file__).resolve().parents[1]
sys.path.insert(0, str(ROOT))

from app.database import engine  # noqa: E402
from app.services.work_schedule import DEFAULT_WORK_SCHEDULE  # noqa: E402


SCHEDULE_FIELDS = [
    "day_start",
    "day_end",
    "lunch_start",
    "lunch_end",
    "dinner_start",
    "dinner_end",
    "overtime_start",
    "overtime_end",
    "night_start",
    "night_end",
]


def column_exists(conn, table: str, column: str) -> bool:
    return bool(conn.execute(text("""
        SELECT COUNT(*)
        FROM information_schema.columns
        WHERE table_schema = DATABASE()
          AND table_name = :table
          AND column_name = :column
    """), {"table": table, "column": column}).scalar_one())


def main() -> None:
    with engine.begin() as conn:
        for field in SCHEDULE_FIELDS:
            if column_exists(conn, "attendance_points", field):
                continue
            conn.execute(text(
                f"ALTER TABLE attendance_points "
                f"ADD COLUMN {field} VARCHAR(5) NOT NULL DEFAULT :default_value AFTER radius_meters"
            ), {"default_value": DEFAULT_WORK_SCHEDULE[field]})

        has_global_schedule = bool(conn.execute(text("""
            SELECT COUNT(*)
            FROM information_schema.tables
            WHERE table_schema = DATABASE()
              AND table_name = 'work_schedules'
        """)).scalar_one())
        if has_global_schedule:
            set_clause = ", ".join(
                f"ap.{field} = COALESCE(ws.{field}, :{field})"
                for field in SCHEDULE_FIELDS
            )
            conn.execute(text(f"""
                UPDATE attendance_points ap
                JOIN work_schedules ws ON ws.id = 1
                SET {set_clause}
            """), DEFAULT_WORK_SCHEDULE)

        for field in SCHEDULE_FIELDS:
            conn.execute(text(
                f"UPDATE attendance_points SET {field} = :default_value "
                f"WHERE {field} IS NULL OR {field} = ''"
            ), {"default_value": DEFAULT_WORK_SCHEDULE[field]})

    print("attendance point schedules migrated")


if __name__ == "__main__":
    main()