import http.server
import socketserver
import urllib.parse
import urllib.request
import paho.mqtt.publish as mq
import time
import json
import struct

PORT = 18001
DATA_SRV_PATH =  "/devicedataservice/dataservice"

BROKER = ('homeproxy', 1883)
TOPIC_PREFIX = 'scalefix/raw'


RESPONSES = {
    0x24:"A00000000000000001000000000000000000000000000000bec650a1",
    0x22:"A20000000000000000000000000000000000000000000000c9950d3f",
    0x25:"A00000000000000001000000000000000000000000000000bec650a1",
    0x28:"A5000000000000000100000000000000000000000000000056e5abd9",
    0x21:"A10000000000000009c4914c0000000000000000000000001d095ec4",
    0x29:""
}


_last_msg = ''
def do_publish(data):
    global _last_msg
    if data != _last_msg:
        now = int(time.time())
        bridge = data[2:14]
        unk_id = data[14:39]
        unk_val = data[30:38]
        weight = int(data[38:42],16) / 100
        bia = (
                int(data[42:50],16),
                int(data[42:46],16),
                int(data[46:50],16)
        )

        msgs = [
                (TOPIC_PREFIX+'/weight', json.dumps({'timestamp':now, 'weight':weight, 'bia':[bia[1],bia[2]]})),
                (TOPIC_PREFIX+'/all', json.dumps({'timestamp':now, 'bridge':bridge, 'unknown_id':unk_id,
                    'unkown_value':unk_val, 'weight':weight, 'bia':[bia[1],bia[2]], 'bia_long':bia[0], 'raw':data}))
        ]
        mq.multiple(msgs, hostname=BROKER[0], port=BROKER[1])
        _last_msg = data


class Handler(http.server.SimpleHTTPRequestHandler):
    
    def do_GET(self):
        #print ('do_GET:%s'%self.path)
        parts = urllib.parse.urlsplit(self.path)

        if parts.path == DATA_SRV_PATH:
            self.do_dataservice(parts)
    
    def do_dataservice(self, urlparts):
        params = urllib.parse.parse_qs(urlparts.query)
        if 'data' not in params:
            print ('got message without data: ' + urlparts.query)
            self.send_error(400,'invalid message')

        data_str = params['data'][0]

        msg_type=int(data_str[0:2],16)

        if msg_type not in RESPONSES:
            print ('got unknown message: ' + data_str)
            self.send_error(400,'unknown message')

        response = RESPONSES[msg_type]

        #print('handle message:%d'%msg_type)
        if msg_type == 0x24:
            do_publish(data_str)

        self.send_response(http.server.HTTPStatus.OK)
        self.send_header("Content-type", "text/html")
        self.send_header("Content-Length", len(response))
        self.end_headers()
        if response:
            self.wfile.write(response.encode('utf-8'))

with socketserver.TCPServer(("",PORT), Handler) as httpd:
    print('started at port %d'%PORT)
    httpd.serve_forever()