#!/usr/bin/env python3
"""
A basic calculator and python interpreter application.
"""
import multiprocessing

import numpy
import numexpr
import requests

from module import commands, example

BASE_TUMBOLIA_URI = 'https://tumbolia-two.appspot.com/'

@commands('calc', 'c')
@example('.c 5 + 3', '8')
def c(bot, trigger):
	"""Evaluates a mathematical expression."""
	if len(trigger.args) < 2:
		return bot.reply("Nothing to calculate.")
	expr = ' '.join(trigger.args[1:])

	def worker(expr, return_dict):
		with numpy.errstate(all='ignore'):
			try:
				value = numexpr.evaluate(expr, local_dict={}, global_dict={})
				value = value.item()
			except:
				value = "Error. The expression was not understood."
			return_dict['value'] = value

	with multiprocessing.Manager() as manager:
		d = manager.dict()
		proc = multiprocessing.Process(target=worker, args=(expr, d))
		proc.start()
		proc.join(1)
		if proc.is_alive():
			proc.kill()
			proc.join()
			proc.close()
			return bot.reply("Calculation timed out.")
		bot.reply(str(d['value']))


@commands('py')
@example('.py len([1,2,3])', '3')
def py(bot, trigger):
	"""Evaluate a Python expression."""
	if len(trigger.args) < 2:
		return bot.msg("Need an expression to evaluate")

	query = trigger.args[1]
	uri = BASE_TUMBOLIA_URI + 'py/'
	res = requests.get(uri + query)
	res.raise_for_status()
	answer = res.text
	answer = answer[:2000]
	if answer:
		bot.msg(answer, length=300)
	else:
		bot.reply('Sorry, no result.')