import os
import json
import subprocess
import platform

from error_codes       import *
from errors            import error_info, is_error, print_errors
from helpers           import general_info, is_metrics_configured, find_dcr_workspace
from .check_endpts     import check_internet_connect, check_ama_endpts
from .check_imds       import check_imds_api

try:
    FileNotFoundError
except NameError:
    FileNotFoundError = IOError

def check_parameters():
    global general_info
    try:
        with open('/etc/default/azuremonitoragent', 'r') as fp:
            for line in fp:
                line = line.split('export')[1].strip()
                key = line.split('=')[0]
                value = line.split('=')[1]
                general_info[key] = value
    except (FileNotFoundError, AttributeError) as e:
        error_info.append((e,))
        return ERR_AMA_PARAMETERS
    return NO_ERROR
   
def check_workspace():
    wkspc_id, wkspc_region, e = find_dcr_workspace()
    if e != None:
        error_info.append((e,))
        return ERR_NO_DCR 
    return NO_ERROR

def check_subcomponents(): 

    services = ['azuremonitoragent']
    services.append('azuremonitor-coreagent')
    services.append('azuremonitor-agentlauncher')

    if is_metrics_configured():
        services.append('metrics-sourcer')
        services.append('metrics-extension')
        
    for service in services:
        try:
            status = subprocess.check_output(['systemctl', 'status', service],\
                                    universal_newlines=True, stderr=subprocess.STDOUT)
            status_lines = status.split('\n')
            for line in status_lines:
                line = line.strip()
                if line.startswith('Active:'):
                    if not line.split()[1] == 'active':
                        error_info.append((service, status))
                        return ERR_SUBCOMPONENT_STATUS
        except subprocess.CalledProcessError as e:
            error_info.append((e,))
            return ERR_CHECK_STATUS
            
    return NO_ERROR

def check_connection(interactive, err_codes=True, prev_success=NO_ERROR):
    print("CHECKING CONNECTION...")

    success = prev_success
    
    # check /etc/default/azuremonitoragent file
    print("Checking AMA parameters in /etc/default/azuremonitoragent...")
    checked_parameters = check_parameters()
    if (is_error(checked_parameters)):
        return print_errors(checked_parameters)
    else:
        success = print_errors(checked_parameters)
        
    # check DCR
    print("Checking DCR...")
    checked_workspace = check_workspace()
    if (is_error(checked_workspace)):
        return print_errors(checked_workspace)
    else:
        success = print_errors(checked_workspace)

    # check general internet connectivity
    print("Checking if machine is connected to the internet...")
    checked_internet_connect = check_internet_connect()
    if (is_error(checked_internet_connect)):
        return print_errors(checked_internet_connect)
    else:
        success = print_errors(checked_internet_connect)


    # check if AMA endpoints connected
    print("Checking if machine can connect to Azure Monitor control-plane and data ingestion endpoints...")
    checked_ama_endpts = check_ama_endpts()
    if (is_error(checked_ama_endpts)):
        return print_errors(checked_ama_endpts)
    else:
        success = print_errors(checked_ama_endpts)

    # check if subcomponents are active (e.g. mdsd, telegraf, etc)
    print("Checking if subcomponents have been started...")
    checked_subcomponents = check_subcomponents()
    if (is_error(checked_subcomponents)):
        return print_errors(checked_subcomponents)
    else:
        success = print_errors(checked_subcomponents)
        
    print("Checking if IMDS metadata and MSI tokens are available...")
    checked_imds_api = check_imds_api()
    if (is_error(checked_imds_api)):
        return print_errors(checked_imds_api)
    else:
        success = print_errors(checked_imds_api)
    return success