import socket
import struct
from db import search_by_date
import re
import json
import time


HOST, PORT = ADDR = '0.0.0.0', 6000
DATATYPE_SIZE = 4  # int


def pack_data(data):
    encoded = data.encode()
    return struct.pack('I', len(encoded)) + encoded


def handle_request(data):
    match = re.match(r'(\d+):?(\d+)?:?(\d+)?-(.*)', data)
    if match:
        *date, msg = match.groups()

        t = time.time()
        found = search_by_date(*map(lambda i: int(i) if i is not None else i, date), msg)
        print(f'Search took {time.time() - t} seconds')
        return pack_data(json.dumps(found))

    else:
        print('String not matched.')
        return pack_data(json.dumps([]))


def get_data(connection):
    buffer = b''
    # Считываем размер пакета
    while len(buffer) < DATATYPE_SIZE:
        data = connection.recv(DATATYPE_SIZE - len(buffer))
        if not data:
            raise ConnectionError('Connection was closed')

        buffer += data

    size_packed, buffer = buffer[:DATATYPE_SIZE], buffer[DATATYPE_SIZE:]
    if not size_packed:
        raise ConnectionError('Connection was closed')

    (size,) = struct.unpack('I', size_packed)
    data = connection.recv(size - len(buffer))
    return buffer + data


def handle_connection(connection, address):
    while True:
        try:
            data = get_data(connection)

        except ConnectionResetError:
            print(f'Connection with {address[0]} was unexpectedly closed')
            break

        except ConnectionError:
            print(f'Connection with {address[0]} was ended')
            break

        except KeyboardInterrupt:
            raise KeyboardInterrupt()

        else:
            if not data:
                print(f'Connection with {address[0]} was ended')
                break
            response = handle_request(data.decode())
            connection.sendall(response)


def main():
    sock = socket.socket()
    sock.bind(ADDR)
    sock.listen(5)

    while True:
        print('Listening for new connections...')
        try:
            connection, address = sock.accept()
            print(f'Got a connection from {address[0]}')
            handle_connection(connection, address)

        except KeyboardInterrupt:
            print('Stopping server...')
            sock.close()
            print('Server stopped')
            break


if __name__ == '__main__':
    success = db.init('otrs_error.log')
    if not success:
        print('Не удалось инициализировать базу данных. Завершаем работу...')
    else:
        main()