#!/bin/env python3
# fedicrawler v4

import json, requests
from multiprocessing.dummy import Pool as ThreadPool 
from urllib.parse import urlparse

start_url = 'https://post.lurk.org'
activity = ''
peers_info ='/api/v1/instance/peers'

proxies = {
'http':'socks5://localhost:12345',
'http':'socks5://localhost:12345'}

pool = ThreadPool(512)

def not_gab(instance):
    #gab does some weird stuff wrt enumerating subdomains
    #example: epa1pu1qcxxyzcxher0u.gab.best
    if instance:
        if 'gab.best'in instance:
            print('GAB', instance)
            return False
        # the ones below are mostly used for testing apps 
        elif 'ngrok.io' in instance:
            print('NGROK', instance)
            return False
        elif 'glitch.me' in instance:
            print('GLITCH', instance)
            return False
        elif 'netlify.app' in instance:
            print('NETLIFY', instance)
        else:
            return True
    else:
        return False

def only_netloc(instance):
    #some peerlists return stuff like
    #mastodon.social/users/blabla or
    #domain.tld/friendica which are all invalid
    return urlparse('https://'+instance).netloc


def multi_filter(fs, l):
    # https://www.reddit.com/r/Python/comments/6xefvp/applying_multiple_filters_to_a_list/
    if not fs:
        return l
    return multi_filter(fs[1:], (x for x in l if fs[0](x)))
    

def get_peers(instance):
    #this is really from the assumption that combined Mastodon & Pleroma 
    #instances have enough view of entire fediverse to rely only on those
    try:
        r = requests.get('https://'+instance+'/api/v1/instance/peers', timeout=3, proxies=proxies)
        if r.status_code == 200:
            peers = r.json()
            print(instance, 'peers with', len(peers))
            return peers
        else:
            # 404s etc
            #print('fail: got {} on {}'.format(r.status_code, instance))
            return
    except Exception as e:
        #network errors etc
        #print('fail on',instance, e)
        #print(e)
        return

def get_nodeinfo(instance):
    nodeinfo_probe = '/.well-known/nodeinfo'
    try:
        r = requests.get('https://{}{}'.format(instance, nodeinfo_probe),timeout=3, proxies=proxies)
        if r.status_code == 200:
            nodeinfo_endpoint = r.json()['links'][0]['href']
            print(nodeinfo_endpoint)
            r = requests.get(nodeinfo_endpoint, timeout=3, proxies=proxies)
            if r.status_code == 200:
                info = {'nodeinfo':r.json()}
            else:
                info = {'error': r.status_code}
        else:
           info = {'error': r.status_code}
    except Exception as e:
        info = {'error': str(e)}
        #print(e)
    return info



def get_instance_info(instance):
    ## no longer used but keeping aroudnd for later maybe
    #instance_info = '/api/v1/instance'
    instance_info = '/.well-known/nodeinfo'
    try:
        r = requests.get('https://'+instance+instance_info, timeout=10, proxies=proxies)
        if r.status_code == 200:
            info = r.json()
            print('info request for {} succeeded'.format(instance))
        elif r.status_code == 400:
            #try to see if its peertube, probably should use a better method
            pt = requests.get('https://'+instance+'/api/v1/config')
            if pt.status_code == 200:
                print('info request for {} succeeded, peertube'.format(instance))
                info = pt.json()
            else:
                info = {'error': r.status_code}
        else:
            #if we get any other http code.. probably needs fixing
            info = {'error': r.status_code}

    except ConnectionError as e:
        info = {'error': 'Connection error: '+str(e)}
    except Exception as e:
        info = {'error': str(e)}
    return info

filters = [not_gab, only_netloc] #what to filter out

instances = set([])
r = requests.get(start_url+peers_info) # normal brain, initial peer list
if r. status_code == 200:
    start_peers = pool.map(get_peers, r.json())  #expanding brain, get all peers of those initial peers
    for i in start_peers:
        if not i:
            start_peers.remove(i)
        else:
            pool.map(instances.add, i)
    # for i in r.json():
    #     instances.add(i)
    instances = set(multi_filter(filters,instances)) # apply filters before we move to network

    network = pool.map(get_peers, instances) #galaxy brain, get all peers of all peers of the initial peers
    for peer_list in network:
        if peer_list:
            for instance in peer_list:
                if not_gab(instance): #prevent gab.best subdomain enumeration
                    instances.add(instance)

    instances = set(multi_filter(filters,instances))

instance_info = pool.map(get_nodeinfo, instances)

scrape = {}
instances_list = list(instances)

for count, value in enumerate(instances_list):
    scrape[value] = instance_info[count]

print('found {} instances'.format(len(scrape)))

pool.close()
pool.join()

with open('instance_scrape.json','w') as f:
    f.write(json.dumps(scrape,indent=4))
    #f.write('\n'.join(text)