import hashlib

import os

import signal

import subprocess

import sys

import time

def time2str(time_used):

    gaps = [

        ('days', 86400000),

        ('h', 3600000),

        ('min', 60000),

        ('s', 1000),

        ('ms', 1)

    ]

    time_used *= 1000

    time_str = []

    for unit, gap in gaps:

        val = time_used // gap

        if val > 0:

            time_str.append('{}{}'.format(int(val), unit))

            time_used -= val * gap

    if len(time_str) == 0:

        time_str.append('0ms')

    return ' '.join(time_str)

def get_date():

    return time.strftime('%Y-%m-%d', time.localtime(time.time()))

def get_time(t=None):

    if t is None:

        t = time.time()

    return time.strftime('%Y-%m-%d %H:%M:%S', time.localtime(t))

def hash_seed(*items, width=32):

    # width: range of seed: [0, 2**width)

    sha = hashlib.sha256()

    for item in items:

        sha.update(str(item).encode('utf-8'))

    return int(sha.hexdigest()[23:23+width//4], 16)

def execute(command, verbose=False, cmd_out_off=False):

    if verbose:

        print(command)

        print()

    if cmd_out_off:

        popen = silent(subprocess.Popen)

    else:

        popen = subprocess.Popen

    p = popen(command, shell=True)

    try:

        p.wait()

    except KeyboardInterrupt:

        try:

            os.kill(p.pid, signal.SIGINT)

        except OSError:

            pass

        p.wait()

def silent(func):

    """

    Make function silent.

    Useful for closing the output if you don't find a switch.

    """

    def wrap_silent(*args, **kwargs):

        fd = os.dup(1)

        sys.stdout.flush()

        os.close(1)

        os.open(os.devnull, os.O_WRONLY)

        res = func(*args, **kwargs)

        os.close(1)

        os.dup(fd)

        os.close(fd)

        return res

    return wrap_silent

def with_time(func, pretty_time=False):

    """

    Usage:

    1. as a function decorator

    ``` python

    @with_time

    def func(...):

        ...

    result, cost_in_seconds = func(...)

    ```

    2. directly apply

    ``` python

    result, cost_in_seconds = with_time(func)(...)

    ```

    """

    def wrap_time(*args, **kwargs):

        start = time.time()

        res = func(*args, **kwargs)

        time_cost = time.time() - start

        if pretty_time:

            time_cost = time2str(time_cost)

        return res, time_cost

    return wrap_time