import numpy as np
import matplotlib.pyplot as plt
import scipy.io as scio
import seaborn as sb
from IPython import embed
sb.set_context("paper")


def plot_sta(times, stim, dt, t_min=-0.1, t_max=.1):
    count = 0
    sta = np.zeros((abs(t_min) + abs(t_max))/dt)
    time = np.arange(t_min, t_max, dt)
    if len(stim.shape) > 1 and stim.shape[1] > 1:
        stim = stim[:,1]
    for i in range(len(times[0])):
        times = np.squeeze(spike_times[0][i])
        for t in times:
            if (int((t + t_min)/dt) < 0) or ((t + t_max)/dt > len(stim)):
                continue;
            
            min_index = int(np.round((t+t_min)/dt))
            max_index = int(np.round((t+t_max)/dt))
            snippet = np.squeeze(stim[ min_index : max_index])            
            sta += snippet
            count += 1
    sta /= count
    
    fig = plt.figure()
    fig.set_size_inches(5, 5)
    fig.subplots_adjust(left=0.15, bottom=0.125, top=0.95, right=0.95, )
    fig.set_facecolor("white")
    
    ax = fig.add_subplot(111)
    ax.plot(time, sta, color="darkblue")
    ax.set_xlabel("time [s]")
    ax.set_ylabel("stimulus")
    ax.xaxis.grid('off')
    ylim = ax.get_ylim()
    xlim = ax.get_xlim()
    ax.plot(list(xlim), [0., 0.], zorder=1, color='darkgray', ls='--')
    ax.plot([0., 0.], list(ylim), zorder=1, color='darkgray', ls='--')
    ax.set_xlim(list(xlim))
    ax.set_ylim(list(ylim))
    fig.savefig("../lecture/images/sta.pdf")
    plt.close()
    return sta


def reconstruct_stimulus(spike_times, sta, stimulus, t_max=30., dt=1e-4):
    s_est = np.zeros((spike_times.shape[1], len(stimulus)))
    for i in range(10):
        times = np.squeeze(spike_times[0][i])
        indices = np.asarray((np.round(times/dt)), dtype=int)
        y = np.zeros(len(stimulus))
        y[indices] = 1
        s_est[i, :] = np.convolve(y, sta, mode='same')

    plt.plot(np.arange(0, t_max, dt), stimulus[:,1], label='stimulus', color='darkblue', lw=2.)
    plt.plot(np.arange(0, t_max, dt), np.mean(s_est, axis=0), label='reconstruction', color='silver', lw=1.5)
    plt.xlabel('time[s]')
    plt.ylabel('stimulus')
    plt.xlim([0.0, 0.25])
    plt.ylim([-1., 1.])
    plt.legend()
    plt.plot([0.0, 0.25], [0., 0.], color="darkgray", lw=1, ls='--', zorder=1)

    fig = plt.gcf()
    fig.set_size_inches(7.5, 5)
    fig.subplots_adjust(left=0.15, bottom=0.125, top=0.95, right=0.95, )
    fig.set_facecolor("white")
    fig.savefig('../lecture/images/reconstruction.pdf')
    plt.close()


if __name__ == "__main__":
    punit_data =  scio.loadmat('../../programming/exercises/p-unit_spike_times.mat')
    punit_stim = scio.loadmat('../../programming/exercises/p-unit_stimulus.mat')
    spike_times = punit_data["spike_times"]
    stimulus = punit_stim["stimulus"]
    sta = plot_sta(spike_times, stimulus, 5e-5, -0.05, 0.05)
    reconstruct_stimulus(spike_times, sta, stimulus, 10, 5e-5)