#! /usr/bin/python

import numpy
import pickle

import sys
import os
sys.path.append(os.path.join(os.path.abspath(os.path.dirname(__file__)),os.pardir))
import helperFunctions

import activeLearningWlinGPprototype

class Classifier(activeLearningWlinGPprototype.ClassifierPrototype):

    def __init__(self,
                 sigmaN = 0.00178,
                 useDiversity = False,
                 useDensity = False,
                 useVariance = False,
                 loNoise = True,
                 configFile=None):

        activeLearningWlinGPprototype.ClassifierPrototype.__init__(self, sigmaN=sigmaN, configFile=configFile)
        self.useDiversity = helperFunctions.getConfig(configFile, 'activeLearning', 'useDiversity', useDiversity, 'bool', True)
        self.useVariance = helperFunctions.getConfig(configFile, 'activeLearning', 'useVariance', useVariance, 'bool', True)
        self.useDensity = helperFunctions.getConfig(configFile, 'activeLearning', 'useDensity', useDensity, 'bool', True)
        self.loNoise = helperFunctions.getConfig(configFile, 'activeLearning', 'loNoise', loNoise, 'bool', True)


    def getDensity(self, sim):
        return numpy.sum(sim, axis=1) / float(sim.shape[1])


    def getDiversity(self, sim):
        return 1.0 / numpy.max(sim, axis=1)


    # x.shape = (feat dim, number of samples)
    def calcAlScores(self, x):

        loNoise = (self.yUni == -1).any() and self.loNoise
        sortedScores = numpy.sort(self.infer(x, loNoise), axis=1)
        alScores = numpy.absolute(sortedScores[:,-1] - sortedScores[:,-2])*(-1.0)
        sim = None

        if self.useDensity:

            sim = numpy.dot(x, numpy.append(self.X, x, axis=0).T)
            density = self.getDensity(sim)
            alScores = numpy.multiply(alScores, density)

        elif self.useDiversity:

            if sim is None:
                sim = numpy.dot(x, self.X.T)
                diversity = self.getDiversity(sim)
            else:
                diversity = self.getDiversity(sim[:,:self.X.shape[0]])

            alScores = numpy.multiply(alScores, diversity)

        elif self.useVariance:

            variance = self.calcSigmaF(x)
            alScores = numpy.multiply(alScores, variance)

        return alScores