"""
@file    miscutils.py
@author  Jakob Erdmann
@author  Michael Behrisch
@date    2012-05-08
@version $Id: miscutils.py 18096 2015-03-17 09:50:59Z behrisch $

Common utility functions

SUMO, Simulation of Urban MObility; see http://sumo.dlr.de/
Copyright (C) 2012-2015 DLR (http://www.dlr.de/) and contributors

This file is part of SUMO.
SUMO is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
"""
import sys
import time
import os
import math
import colorsys
import socket
import random
from collections import defaultdict

# append import path stanca:
#THIS_DIR == os.path.basename(__file__)
#sys.path.append(os.path.join(THIS_DIR, 'foo', 'bar'))

# http://www.python.org/dev/peps/pep-0326/


class _ExtremeType(object):

    def __init__(self, cmpr, rep):
        object.__init__(self)
        self._cmpr = cmpr
        self._rep = rep

    def __cmp__(self, other):
        if isinstance(other, self.__class__) and\
           other._cmpr == self._cmpr:
            return 0
        return self._cmpr

    def __repr__(self):
        return self._rep

uMax = _ExtremeType(1, "uMax")
uMin = _ExtremeType(-1, "uMin")

# decorator for timing a function


def benchmark(func):
    def benchmark_wrapper(*args, **kwargs):
        started = time.time()
        now = time.strftime("%a, %d %b %Y %H:%M:%S +0000", time.localtime())
        print('function %s called at %s' % (func.__name__, now))
        sys.stdout.flush()
        result = func(*args, **kwargs)
        print('function %s finished after %f seconds' %
              (func.__name__, time.time() - started))
        sys.stdout.flush()
        return result
    return benchmark_wrapper


class Statistics:

    def __init__(self, label=None, abs=False, histogram=False, printMin=True, scale=1):
        self.label = label
        self.min = uMax
        self.min_label = None
        self.max = uMin
        self.max_label = None
        self.values = []
        self.abs = abs
        self.printMin = printMin
        self.scale = scale
        if histogram:
            self.counts = defaultdict(int)
        else:
            self.counts = None

    def add(self, v, label=None):
        self.values.append(v)
        if v < self.min:
            self.min = v
            self.min_label = label
        if v > self.max:
            self.max = v
            self.max_label = label
        if self.counts is not None:
            self.counts[int(round(v / self.scale))] += 1

    def update(self, other):
        for v in other.values:
            self.add(v)

    def clear(self):
        self.min = uMax
        self.min_label = None
        self.max = uMin
        self.max_label = None
        self.values = []
        if self.counts:
            self.counts.clear()

    def count(self):
        return len(self.values)

    def avg(self):
        """return the mean value"""
        # XXX rename this method
        if len(self.values) > 0:
            return sum(self.values) / float(len(self.values))
        else:
            return None

    def avg_abs(self):
        """return the mean of absolute values"""
        # XXX rename this method
        if len(self.values) > 0:
            return sum(map(abs, self.values)) / float(len(self.values))
        else:
            return None

    def relStdDev(self, limit=None):
        """return the relative standard deviation optionally limited to the last limit values"""
        if limit is None or len(self.values) < limit:
            limit = len(self.values)
        if limit > 0:
            mean = sum(self.values[-limit:]) / float(limit)
            sumSq = 0.
            for v in self.values[-limit:]:
                sumSq += (v - mean) * (v - mean)
            return math.sqrt(sumSq / limit) / mean
        else:
            return None

    def mean(self):
        """return the median value"""
        # XXX rename this method
        if len(self.values) > 0:
            return sorted(self.values)[len(self.values) / 2]
        else:
            return None

    def mean_abs(self):
        """return the median of absolute values"""
        # XXX rename this method
        if len(self.values) > 0:
            return sorted(map(abs, self.values))[len(self.values) / 2]
        else:
            return None

    def average_absolute_deviation_from_mean(self):
        if len(self.values) > 0:
            m = self.avg()
            return sum([abs(v - m) for v in self.values]) / len(self.values)
        else:
            return None

    def median(self):
        return self.mean()

    def median_abs(self):
        return self.mean_abs()

    def quartiles(self):
        s = sorted(self.values)
        return s[len(self.values) / 4], s[len(self.values) / 2], s[3 * len(self.values) / 4]

    def rank(self, fraction):
        if len(self.values) > 0:
            return sorted(self.values)[int(round(len(self.values) * fraction + 0.5))]
        else:
            return None

    def histogram(self):
        return [(k * self.scale, self.counts[k]) for k in sorted(self.counts.keys())]

    def __str__(self):
        if len(self.values) > 0:
            min = ''
            if self.printMin:
                min = 'min %.2f%s, ' % (self.min,
                                        ('' if self.min_label is None else ' (%s)' % (self.min_label,)))
            result = '%s: count %s, %smax %.2f%s, mean %.2f' % (
                self.label, len(self.values), min,
                self.max,
                ('' if self.max_label is None else ' (%s)' %
                 (self.max_label,)),
                self.avg())
            result += ' Q1 %.2f, median %.2f, Q3 %.2f' % self.quartiles()
            if self.abs:
                result += ', mean_abs %.2f, median_abs %.2f' % (
                    self.avg_abs(), self.mean_abs())
            if self.counts is not None:
                result += '\n histogram: %s' % self.histogram()
            return result
        else:
            return '"%s": no values' % self.label


def geh(m, c):
    """Error function for hourly traffic flow measures after Geoffrey E. Havers"""
    if m + c == 0:
        return 0
    else:
        return math.sqrt(2 * (m - c) * (m - c) / (m + c))


# temporarily change working directory using 'with' statement
class working_dir:

    def __init__(self, dir):
        self.dir = dir
        self.origdir = os.getcwd()

    def __enter__(self):
        os.chdir(self.dir)

    def __exit__(self, type, value, traceback):
        os.chdir(self.origdir)


class Colorgen:

    def __init__(self, hsv):
        self.hsv = hsv

    def get_value(self, opt):
        if opt == 'random':
            return random.random()
        else:
            return float(opt)

    def floatTuple(self):
        """return color as a tuple of floats each in [0,1]"""
        return colorsys.hsv_to_rgb(*map(self.get_value, self.hsv))

    def byteTuple(self):
        """return color as a tuple of bytes each in [0,255]"""
        return tuple([int(round(255 * x)) for x in self.floatTuple()])

    def __call__(self):
        """return constant or randomized rgb-color string"""
        return ','.join(map(str, self.byteTuple()))


def getFreeSocketPort(numTries=10, minPort=8000, maxPort=50000):
    for i in range(numTries):
        try:
            p = random.randint(minPort, maxPort)
            s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
            s.bind(("localhost", p))
            s.close()
            return p
        except socket.error:
            pass
    return None
