import numpy as np
from time import time


# main logic function
def main(result_file = 'test_output.csv', vlan_file = 'vlans.csv', requests_file = 'requests.csv'):
    # get files: with vlans data and requests data
    vlan_csv, requests_csv = read_data(vlan_file, requests_file)

    sorted_by_vlan_id = np.sort(vlan_csv.view('int, int, int'), kind='mergesort', order=['f2', 'f0'], axis=0)
    # maximum number of elements
    output_rows = len(requests_csv[requests_csv.transpose()[1] == 0]) + len(requests_csv[requests_csv.transpose()[1] == 1]) * 2
    # create zero-dataframe
    out_data = [np.zeros(output_rows, dtype=int) for i in range(4)]

    # index for slice
    no_redundancy_start = 0
    with_redundancy_start = 0
    idx = 0

    for request_data in requests_csv:
        # processing of non redundant requests
        if not request_data[1]:
            for index, element in enumerate(sorted_by_vlan_id[no_redundancy_start:]):
                element = element[0]
                if not element[2]:
                    continue
                elif element[1]:
                    # adding data in array
                    out_data[0][idx] = request_data[0]
                    out_data[1][idx] = element[0]
                    out_data[2][idx] = 1
                    out_data[3][idx] = element[2]

                    # drop data
                    sorted_by_vlan_id[index + no_redundancy_start] = b'\x00'

                    no_redundancy_start = index + no_redundancy_start + 1
                    break

        # processing of redundant requests
        elif request_data[1]:
            # params where we save data about pair elements
            device_id, vlan_id, primary, secondary = None, None, None, None

            for index, element in enumerate(sorted_by_vlan_id[with_redundancy_start:]):
                element = element[0]
                if not element[2]:
                    continue
                if not device_id or element[0] != device_id or not vlan_id or element[2]!= vlan_id:
                    # update params
                    device_id = element[0]
                    vlan_id = element[2]
                if element[1]:
                    primary = index + with_redundancy_start
                else:
                    secondary = index + with_redundancy_start

                if primary is not None and secondary is not None:
                    # drop data
                    sorted_by_vlan_id[primary] = b'\x00'
                    sorted_by_vlan_id[secondary] = b'\x00'

                    # adding data in array
                    out_data[0][idx:idx + 2] = request_data[0]
                    out_data[1][idx:idx + 2] = device_id
                    out_data[3][idx:idx + 2] = vlan_id
                    out_data[2][idx] = 0
                    out_data[2][idx + 1] = 1

                    with_redundancy_start = index + with_redundancy_start + 1
                    break
            idx += 1
        idx += 1

    np.savetxt(result_file, np.array(out_data).transpose(), fmt="%d", delimiter=",", newline="\n",
               header='request_id,device_id,primary_port,vlan_id', comments="")


# reading data from files and cleaning it
def read_data(vlan_file, requests_file):
    vlans = np.loadtxt(open(vlan_file, 'rb'), delimiter=",", skiprows=1, dtype=int)
    requests = np.loadtxt(open(requests_file, 'rb'), delimiter=",", skiprows=1, dtype=int)

    return vlans, requests

if __name__ == '__main__':
    for i in range(10):

        tic = time()
        main()
        tac = time()
        print(tac-tic)