import socket
from rest_framework.exceptions import ParseError
import json
import time
from django.core.cache import cache
from apps.utils.thread import MyThread
import struct
import uuid
import logging
import threading

myLogger = logging.getLogger('log')

def get_checksum(body_msg):
    return sum(body_msg) & 0xFF

def handle_bytes(arr):
    if len(arr) < 8:
        return "返回数据长度错误"
    
    if arr[0] != 0xEB or arr[1] != 0x90:
        return "数据头不正确"


    # 读取长度信息
    length_arr = arr[2:4][::-1]  # 反转字节
    length = int.from_bytes(length_arr, byteorder='little', signed=True)  # 小端格式
    
    # 提取内容
    body = arr[4:4 + length - 3]

    # 校验和检查
    check_sum = get_checksum(body)
    if check_sum != arr[length + 1]:
        return "校验错误"
        

    # 尾部标识检查
    if arr[length + 2] != 0xFF or arr[length + 3] != 0xFE:
        return "尾错误"

    content = body.decode('utf-8')

    res = json.loads(content)
    
    return res[0]

def get_tyy_data_t(host, port, tid):
    cd_thread_key_id = f"cd_thread_{host}_{port}_id"
    cd_thread_key_val = f"cd_thread_{host}_{port}_val"
    sc = None
    def connect_and_send(retry=1):
        nonlocal sc
        try:
            if sc is None:
                sc = socket.socket()
                sc.connect((host, int(port)))
            sc.sendall(b"R")
        except BrokenPipeError:
            if retry > 0:
                connect_and_send(retry-1)
            else:
                if sc:
                    try:
                        sc.close()
                    except Exception:
                        pass
                sc = None
        except OSError as e:
            sc = None
            cache.set(cd_thread_key_val, {"err_msg": f"采集器连接失败-{str(e)}"})
        except ConnectionResetError:
            sc = None
            cache.set(cd_thread_key_val, {"err_msg": "采集器重置了连接"})
        except socket.timeout:
            sc = None
            cache.set(cd_thread_key_val, {"err_msg": "采集器连接超时"})
        except Exception as e:
            sc = None
            cache.set(cd_thread_key_val, {"err_msg": f"采集器连接失败-{str(e)}"})

    while cache.get(cd_thread_key_id) == tid:
        if cache.get(cd_thread_key_val) == "get":
            cache.set(cd_thread_key_val, "working")
            connect_and_send()
            if sc is None:
                continue
            resp = sc.recv(1024)
            res = handle_bytes(resp)
            if isinstance(res, str):
                cache.set(cd_thread_key_val, {"err_msg": f'采集器返回数据错误-{res}'})
            elif not res:
                cache.set(cd_thread_key_val, {"err_msg": f"采集器返回数据为空-{str(res)}"})
            else:
                myLogger.info(f"采集器返回数据-{res}")
                cache.set(cd_thread_key_val, res)
        time.sleep(0.3)

    if sc:
        try:
            sc.close()
        except Exception:
            pass

def get_tyy_data_2(*args, retry=1):
    host, port = args[0], int(args[1])
    cd_thread_key_id = f"cd_thread_{host}_{port}_id"
    cd_thread_key_val = f"cd_thread_{host}_{port}_val"
    cd_thread_val_id = cache.get(cd_thread_key_id, default=None)
    if cd_thread_val_id is None:
        tid = uuid.uuid4()
        cache.set(cd_thread_key_id, tid, timeout=10800)
        cd_thread = MyThread(target=get_tyy_data_t, args=(host, port, tid), daemon=True)
        cd_thread.start()
    cache.set(cd_thread_key_val, "get")
    num = 0
    get_val = False

    while True:
        num += 1
        if num > 8:
            break
        val = cache.get(cd_thread_key_val)
        if isinstance(val, dict):
            get_val = True
            if "err_msg" in val:
                raise ParseError(val["err_msg"])
            return val
        time.sleep(0.3)

    if not get_val and retry > 0:
        cache.set(cd_thread_key_id, None)
        get_tyy_data_2(*args, retry=retry-1)


sc_all = {}
sc_lock = threading.Lock()

def get_tyy_data(*args, retry=1):
    host, port = args[0], int(args[1])
    global sc_all
    sc = None
    
    def connect_and_send(retry=1):
        nonlocal sc
        sc = sc_all.get(f"{host}_{port}", None)
        try:
            if sc is None:
                sc = socket.socket()
                sc.settimeout(5)  # 设置超时
                sc.connect((host, port))
                sc_all[f"{host}_{port}"] = sc
            else:
                # 清空接收缓冲区
                sc.settimeout(0.1)  # 设置短暂超时
                for _ in range(5):
                    try:
                        data = sc.recv(65536)
                        if not data:
                            break
                    except (socket.timeout, BlockingIOError):
                        break
                sc.settimeout(5)  # 恢复原超时设置
            sc.sendall(b"R")
        except BrokenPipeError:
            if retry > 0:
                if sc:
                    try:
                        sc.close()
                    except Exception:
                        pass
                    sc_all.pop(f"{host}_{port}", None)
                return connect_and_send(retry-1)
            else:
                if sc:
                    try:
                        sc.close()
                    except Exception:
                        pass
                    sc_all.pop(f"{host}_{port}", None)
                sc = None
                raise ParseError("采集器连接失败-管道重置")
        except OSError as e:
            if sc:
                try:
                    sc.close()
                except Exception:
                    pass
                sc_all.pop(f"{host}_{port}", None)
            sc = None
            raise ParseError(f"采集器连接失败-{str(e)}")
        except TimeoutError as e:
            if sc:
                try:
                    sc.close()
                except Exception:
                    pass
                sc_all.pop(f"{host}_{port}", None)
            sc = None
            raise ParseError(f"采集器连接超时-{str(e)}")
    
    with sc_lock:
        connect_and_send()
        resp = sc.recv(1024)
        res = handle_bytes(resp)
        # myLogger.error(res)
        if isinstance(res, str):
            raise ParseError(f'采集器返回数据错误-{res}')
        else:
            return res