# -*- coding: utf-8 -*-

import numpy as np

class SinSignalx(object):
    """docstring for SinSignalx    
    Parameters
    ----------
    freq : the frequency of the signal
    
    signal_amp: the amplitude of the signal

    noise_amp:the amplitude of the noise

    """
    def __init__(self,freq,signal_amp,noise_amp):
        super(SinSignalx, self).__init__()
        self.sn = 128 #sample number
        t = np.linspace(0, 1, self.sn, endpoint=False)
        u = np.sin(2*np.pi*freq*t)*signal_amp
        n = np.random.rand(self.sn)*noise_amp
        self.s = u+n
        self.pointer = 0

    def __add__(self, o):
        self.s = self.s+o.s
        return self

    def get_data_points(self,n):
        next_idx = self.pointer+n
        if next_idx>=self.sn:
            remainder_n = next_idx - self.sn            
            tmp = self.s[self.pointer:]
            tmp2 = self.s[:remainder_n]
            self.pointer=remainder_n
            return np.concatenate((tmp,tmp2),axis=0)
        else:
            tmp = self.s[self.pointer:next_idx]
            self.pointer=next_idx
            return tmp