import psycopg as pg
from .connection import g_conn_dict as conn

# no undo/redo

_project_open_count: dict[str, int] = {}

def have_project(name: str) -> bool:
    with pg.connect(conninfo="dbname=postgres host=127.0.0.1", autocommit=True) as conn:
        with conn.cursor() as cur:
            cur.execute(f"select * from pg_database where datname = '{name}'")
            return cur.rowcount > 0

def copy_project(source: str, new: str) -> None:
    with pg.connect(conninfo="dbname=postgres host=127.0.0.1", autocommit=True) as conn:
        with conn.cursor() as cur:
            cur.execute(f"create database {new} with template = {source}")

def create_project(name: str) -> None:
    return copy_project('project', name)

def delete_project(name: str) -> None:
    with pg.connect(conninfo="dbname=postgres host=127.0.0.1", autocommit=True) as conn:
        with conn.cursor() as cur:
            cur.execute(f"drop database {name}")

def open_project(name: str) -> None:
    if name not in _project_open_count:
        conn[name] = pg.connect(conninfo=f"dbname={name} host=127.0.0.1", autocommit=True)
        _project_open_count[name] = 0

    _project_open_count[name] += 1

def is_project_open(name: str) -> bool:
    return name in conn

def close_project(name: str) -> None:
    if name in _project_open_count:
        _project_open_count[name] -= 1
        if _project_open_count[name] == 0:
            conn[name].close()
            del conn[name]
            del _project_open_count[name]