from socket import *
import struct
import threading

HOST = ''
PORT = 12345

s = socket(AF_INET, SOCK_DGRAM)
s.settimeout(2)
s.bind((HOST, PORT))

buf_t = []
buf_v = []
lock = threading.Lock()
flag_thread_stop = False

def func_thread():
        while (flag_thread_stop == False):
                try:
                        bv, addr = s.recvfrom(16*100)
                        size = len(bv)
                        lock.acquire()
                        for i in range(size/16):
                                vv = struct.unpack('dd', bv[i*16:(i+1)*16])
                                buf_t.append(vv[0])
                                buf_v.append(vv[1])
                        lock.release()
                except timeout:
                        pass
                print("loop")
                time.sleep(0.01)

thread_udp = threading.Thread(target=func_thread)
thread_udp.start()


t = np.zeros(100)
y = np.zeros(100)

plt.ion()
fig = plt.figure()
ax = fig.add_subplot(111)
li, = plt.plot(t, y)
plt.ylim(0, 1)
plt.show(block=False)
fig.canvas.draw()

background = fig.canvas.copy_from_bbox(ax.bbox)

t0 = time.time()

while True:
        try:
                time.sleep(0.01)
                flag_update = False
                lock.acquire()
                num = len(buf_t)
                for i in range(num):
                        t = np.append(t, buf_t[i]-t0)
                        t = np.delete(t, 0)
                        y = np.append(y, buf_v[i])
                        y = np.delete(y, 0)
                        flag_update = True
                buf_t = []
                buf_v = []

                lock.release()

                if(flag_update == False):
                        continue
                li.set_xdata(t)
                li.set_ydata(y)
                plt.xlim(min(t), max(t))
                plt.draw()
                fig.canvas.restore_region(background)
                ax.draw_artist(li)
                fig.canvas.blit(ax.bbox)
        except KeyboardInterrupt:
                print("interrupt")
                flag_thread_stop = True
                print("join")
                thread_udp.join()
                print("join end")
                break