import pymysql
from getpass import getpass
from .connection import conn
from .settings import config
from .utils import user_choice


def set_password(
    new_password=None, connection=None, update_config=None
):  # pragma: no cover
    connection = conn() if connection is None else connection
    if new_password is None:
        new_password = getpass("New password: ")
        confirm_password = getpass("Confirm password: ")
        if new_password != confirm_password:
            print("Failed to confirm the password! Aborting password change.")
            return
    connection.query("SET PASSWORD = PASSWORD('%s')" % new_password)
    print("Password updated.")

    if update_config or (
        update_config is None and user_choice("Update local setting?") == "yes"
    ):
        config["database.password"] = new_password
        config.save_local(verbose=True)


def kill(restriction=None, connection=None, order_by=None):  # pragma: no cover
    """
    view and kill database connections.

    :param restriction: restriction to be applied to processlist
    :param connection: a datajoint.Connection object. Default calls datajoint.conn()
    :param order_by: order by a single attribute or the list of attributes. defaults to 'id'.

    Restrictions are specified as strings and can involve any of the attributes of
    information_schema.processlist: ID, USER, HOST, DB, COMMAND, TIME, STATE, INFO.

    Examples:
        dj.kill('HOST LIKE "%compute%"') lists only connections from hosts containing "compute".
        dj.kill('TIME > 600') lists only connections in their current state for more than 10 minutes
    """

    if connection is None:
        connection = conn()

    if order_by is not None and not isinstance(order_by, str):
        order_by = ",".join(order_by)

    query = (
        "SELECT * FROM information_schema.processlist WHERE id <> CONNECTION_ID()"
        + ("" if restriction is None else " AND (%s)" % restriction)
        + (" ORDER BY %s" % (order_by or "id"))
    )

    while True:
        print("  ID USER         HOST          STATE         TIME    INFO")
        print("+--+ +----------+ +-----------+ +-----------+ +-----+")
        cur = (
            {k.lower(): v for k, v in elem.items()}
            for elem in connection.query(query, as_dict=True)
        )
        for process in cur:
            try:
                print(
                    "{id:>4d} {user:<12s} {host:<12s} {state:<12s} {time:>7d}  {info}".format(
                        **process
                    )
                )
            except TypeError:
                print(process)
        response = input('process to kill or "q" to quit > ')
        if response == "q":
            break
        if response:
            try:
                pid = int(response)
            except ValueError:
                pass  # ignore non-numeric input
            else:
                try:
                    connection.query("kill %d" % pid)
                except pymysql.err.InternalError:
                    print("Process not found")


def kill_quick(restriction=None, connection=None):
    """
    Kill database connections without prompting. Returns number of terminated connections.

    :param restriction: restriction to be applied to processlist
    :param connection: a datajoint.Connection object. Default calls datajoint.conn()

    Restrictions are specified as strings and can involve any of the attributes of
    information_schema.processlist: ID, USER, HOST, DB, COMMAND, TIME, STATE, INFO.

    Examples:
        dj.kill('HOST LIKE "%compute%"') terminates connections from hosts containing "compute".
    """
    if connection is None:
        connection = conn()

    query = (
        "SELECT * FROM information_schema.processlist WHERE id <> CONNECTION_ID()"
        + ("" if restriction is None else " AND (%s)" % restriction)
    )

    cur = (
        {k.lower(): v for k, v in elem.items()}
        for elem in connection.query(query, as_dict=True)
    )
    nkill = 0
    for process in cur:
        connection.query("kill %d" % process["id"])
        nkill += 1
    return nkill
