import socket
import threading
import queue
import random
import struct
import time
import math
import pyproj
import vdes_protocol

class vdes_server:
    def __init__(self, host='localhost', port=10):
        self.host = host
        self.port = port
        self.bufsize = 32768
        self.addr = (self.host, self.port)
        self.tcp_send_queue = queue.Queue(32)
        self.tcp_recv_queue = queue.Queue(16)
        self.tcp_recv_buffer = bytearray()
        self.tcp_recv_pointer = 0
        self.rf_recv_queue = queue.Queue(32)
        self.rf_recv_buffer = bytearray()
        self.rf_recv_pointer = 0

        self.tcpCliSock = None
        self.tcpSerSock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        self.tcpSerSock.bind(self.addr)
        self.tcpSerSock.listen(2)

        self.my_lon = 121.167
        self.my_lat = 31.187
        self.my_heading = 270
        self.gps_data = vdes_protocol.pkt_gps(self.my_lon, self.my_lat, 0, 0, self.my_heading)
        # 模拟 40 条船只以本设备为中心 4 ~ 7 海里距离，角度均分，方向随机为离心或向心
        self.ais_data = list()
        for i in range(40):
            radius = random.randint(40, 70)/10*1852 # distributed in 4 ~ 7 nautical miles
            ship_direction = random.randint(0, 1)
            ship_heading = (i*9 + ship_direction*180) % 360
            # Use WGS84 ellipsoid.
            g = pyproj.Geod(ellps='WGS84')
            # Forward transformation - returns longitude, latitude, back azimuth of terminus points
            ship_lon, ship_lat, az = g.fwd(self.my_lon, self.my_lat, ship_heading, radius)
            ship_mmsi = random.randint(100000000, 999999999)
            ship_speed = random.randint(14, 30)
            self.ais_data.append(vdes_protocol.pkt_ais_msg_1(ship_mmsi, ship_speed, ship_lon, ship_lat, ship_heading))

    def recv_parse(self):
        pass

    def send(self, stop_event):
        print("send started.")
        while not stop_event.is_set():
            if self.tcp_send_queue.empty():
                time.sleep(0.01)
                continue
            data = self.tcp_send_queue.get()
            if self.tcpCliSock:
                self.tcpCliSock.send(data)

    def make_response(self, stop_event):
        print("make_response started.")
        while not stop_event.is_set():
            if self.tcp_recv_queue.empty():
                time.sleep(0.1)
                continue
            recv_data += self.tcp_recv_queue.get()

    def make_gps(self, stop_event):
        print("make_gps started.")
        while not stop_event.is_set():
            self.tcp_send_queue.put(self.gps_data.get_packet())
            self.tcp_send_queue.task_done()
            time.sleep(1)

    def make_ais(self, stop_event):
        print("make_ais started.")
        while not stop_event.is_set():
            for data in self.ais_data:
                if stop_event.is_set():
                    break
                data = data.get_packet(data.sog * 1852 / 3600 * 2) # 速度放大10倍
                self.tcp_send_queue.put(data)
                self.tcp_send_queue.task_done()
                time.sleep(0.05)

    def start(self):
        threads = []

        while True:
            print('Waiting for connection...')
            self.tcpCliSock, addr = self.tcpSerSock.accept()
            print('...connected from:', addr)

            stop_event_response = threading.Event()
            threads.append(threading.Thread(target=self.make_response, args=(stop_event_response,)))
            stop_event_gps = threading.Event()
            threads.append(threading.Thread(target=self.make_gps, args=(stop_event_gps,)))
            stop_event_ais = threading.Event()
            threads.append(threading.Thread(target=self.make_ais, args=(stop_event_ais,)))
            stop_event_send = threading.Event()
            threads.append(threading.Thread(target=self.send, args=(stop_event_send,)))

            for t in threads:
                t.start()
            
            try:
                while True:
                    recv_data = self.tcpCliSock.recv(self.bufsize)
                    if not recv_data:
                        print("Client disconnected")
                        break
                    self.tcp_recv_queue.put(recv_data)
            except (ConnectionResetError, BrokenPipeError):
                print("Client forcibly disconnected")
            except Exception as e:
                print(f"Error: {e}")
            finally:
                self.tcpCliSock.close()

            stop_event_response.set()
            stop_event_gps.set()
            stop_event_ais.set()
            stop_event_send.set()
            for t in threads:
                t.join()

            threads.clear()
            self.tcpCliSock = None


if __name__ == "__main__":
    server = vdes_server()
    try:
        server.start()
    except KeyboardInterrupt:
        print("Server stopped by user")
    finally:
        if server.tcpCliSock:
            server.tcpCliSock.close()
        server.tcpSerSock.close()