from psycopg.rows import dict_row, Row
from .connection import g_conn_dict as conn
from .s0_base import *
from .operation import *
from .change_set import ChangeSet


def _to_point(coord: str) -> dict[str, float]:
    coord = coord.removeprefix('(')
    coord = coord.removesuffix(')')
    coord = coord.split(',')
    return { 'x': float(coord[0]), 'y': float(coord[1]) }


def get_node_coord(name: str, id: str) -> dict[str, float] | None:
    with conn[name].cursor(row_factory=dict_row) as cur:
        cur.execute(f"select * from coordinates where node = '{id}'")
        row = cur.fetchone()
        if row == None:
            return None
        
        coord = str(row['coord'])
        return _to_point(coord)


def set_node_coord(name: str, id: str, x: float, y: float) -> ChangeSet:
    if not is_junction(name, id):
        return

    old = get_node_coord(name, id)
    if old == None:
        return
    old_x, old_y = old['x'], old['y']

    with conn[name].cursor() as cur:
        sql = f"update coordinates set coord = '({x},{y})' where node = '{id}'"
        cur.execute(sql)

        redo = sql.replace("'", '"')
        undo = f'update coordinates set coord = "({old_x},{old_y})" where node = "{id}"'
        add_operation(name, redo, undo)

    change = ChangeSet()
    change.update('junction', id, 'coord', 'point', str({'x': x, 'y': y}))
    return change