#!/usr/bin/python
# -*- coding: utf-8 -*-

from __future__ import print_function
import io
import json
import re
import string
import subprocess
import time

import ffstatus
from .exceptions import SanityCheckError


class BatmanParser:
    batadv_vis = 'batadv-vis'
    batctl = 'batctl'
    mactranslation = string.maketrans('2367abef', '014589cd')

    def __str__(self):
        return 'BatmanParser using \'{0}\' and \'{1}\''.format(
            self.batadv_vis, self.batctl)

    def sanitycheck(self):
        """Checks that programs are executable and give sane output."""

        testdata = None
        try:
            cmd = [self.batadv_vis, '-f', 'jsondoc']
            testdata = subprocess.check_output(cmd)
        except Exception as err:
            raise SanityCheckError(
                self, "batadv-vis not found or incompatible", err)

        try:
            json.loads(testdata)
        except Exception as err:
            raise SanityCheckError(
                self, "batadv-vis does not return valid JSON data", err)

        try:
            cmd = [self.batctl, 'vd', 'json', '-n']
            testdata = subprocess.check_output(cmd)
        except Exception as err:
            raise SanityCheckError(
                self, "batctl not found or incompatible", err)

        lineno = 0
        try:
            for line in testdata.splitlines():
                lineno += 1
                json.loads(line)
        except Exception as err:
            raise SanityCheckError(
                self,
                "batctl does not return valid JSON data (line " + lineno + ")",
                err)

        return True

    def fetch(self):
        """Fetches the current data from batadv-vis."""

        data = {}
        timestamp = int(time.time())

        # call 'batctl vd json -n' and parse output line-wise as JSON
        rawvisdata = subprocess.check_output([self.batctl, 'vd', 'json', '-n'])
        visdata = [json.loads(line) for line in rawvisdata.splitlines()]

        # call 'batctl gwl' and parse output lines
        rawgwdata = subprocess.check_output([self.batctl, 'gwl'])
        gateways = []
        for l in rawgwdata.splitlines()[1:]:
            m = re.search("^\s*(([a-fA-F0-9]{2}:){5}[a-fA-F0-9]{2})\s+", l)
            if m is not None:
                gateways.append(ffstatus.mac2id(m.group(1)))
            else:
                print('Failed to parse gateway from batctl-gwl line:', l)

        # call batadv-vis and parse output as unicode JSON
        rawdata = subprocess.check_output([self.batadv_vis, '-f', 'jsondoc'])
        rawdata = unicode(rawdata, encoding='latin1', errors='replace')
        batmandata = json.loads(rawdata)

        # parse vis data
        for item in visdata:
            itemmac = item.get('primary', item.get('router'))
            itemid = ffstatus.mac2id(itemmac)
            content = {
                'aliases': [],
                'neighbours': {},
                '__UPDATED__': {'batctl': timestamp},
                '__RAW__': {'batctl': [item]},
            }

            neigh_id = ffstatus.mac2id(item.get('neighbor'))
            if neigh_id is not None:
                neigh_q = item.get('label', '0')
                if neigh_q != 'TT':
                    neigh_q = float(neigh_q)
                else:
                    neigh_q = None
                content['neighbours'][neigh_id] = neigh_q

            if itemid is None:
                # assumption: this is a secondary
                secid = ffstatus.mac2id(item.get('secondary'))
                ofid = ffstatus.mac2id(item.get('of'))
                if secid is None or ofid is None:
                    print('BATCTL-VD threw garbage: ' + json.dumps(item))
                    continue

                itemid = ofid
                content['aliases'].append(secid)
            else:
                if not 'mac' in content:
                    content['mac'] = itemmac
                if itemid in gateways:
                    content['type'] = 'gateway'

            if itemid in data:
                data[itemid] = ffstatus.dict_merge(
                    data[itemid], content, overwrite_lists=False)
            else:
                data[itemid] = content

        # parse raw data, convert all MAC into nodeid
        for item in batmandata['vis']:
            itemid = ffstatus.mac2id(item['primary'])
            aliases = []
            if 'secondary' in item:
                for mac in item['secondary']:
                    aliases.append(ffstatus.mac2id(mac))

            neighbours = {}
            if 'neighbors' in item:
                for neighbour in item['neighbors']:
                    #if neighbour['router'] != item['primary']:
                    #   print('node {0}\'s neighbor {1} has unexpected router {2}'.format(itemid, neighbour['neighbor'], neighbour['router']))

                    metric = float(neighbour['metric'])
                    neighbours[neighbour['neighbor']] = metric

            # construct dict entry as expected by BATCAVE
            content = {
                'aliases': aliases,
                'neighbours': neighbours,
                'clients': [x for x in item.get('clients', [])],
                '__UPDATED__': {'batadv': timestamp},
                '__RAW__': {'batadv': {itemid: item}},
            }

            if itemid in data:
                data[itemid] = ffstatus.dict_merge(
                    data[itemid], content, overwrite_lists=False)
            else:
                data[itemid] = content

        return data

# standalone test mode
if __name__ == "__main__":
    parser = BatmanParser()

    try:
        parser.sanitycheck()
    except SanityCheckError as err:
        print('SANITY-CHECK failed:', str(err))
        import sys
        sys.exit(1)

    bdata = parser.fetch()
    print(json.dumps(bdata))