#!/usr/bin/env python3

import requests
import time
import json
import pprint
import socket
import sys
import re
import random
import os

# shouts to @mewmew@blob.cat:
# https://blob.cat/notice/9u8rxBOMWtDFFQG81Y
SEEDS = [
    "blob.cat",
    "s.sneak.berlin"
]

TIMEOUT_SECS = 5

fakehostre = re.compile('gab\.best$')

simplehostre = re.compile('^[A-Za-z0-9\-\.]+$')

def main():
    os.environ['PYTHONUNBUFFERED'] = '1'
    knownhosts = {}
    goodhosts = {}
    badhosts = {}
    fetchqueue = {}

    for seed in SEEDS:
        fetchqueue[seed] = True

    if os.path.exists('fetchqueue.json'):
        with open('fetchqueue.json') as f:
            t = json.load(f)
            for i in t:
                fetchqueue[i] = True
            print(f"loaded {len(t)} fetchqueue items")

    if os.path.exists('goodhosts.json'):
        with open('goodhosts.json') as f:
            t = json.load(f)
            for i in t:
                goodhosts[i] = True
        print(f"loaded {len(t)} goodhosts")

    if os.path.exists('badhosts.json'):
        with open('badhosts.json') as f:
            t = json.load(f)
            for i in t:
                badhosts[i] = True
        print(f"loaded {len(t)} badhosts")

    def fetchnext(hostname):
        hostname = str(hostname)
        del fetchqueue[hostname]

        try:
            addr = socket.gethostbyname(hostname)
        except:
            print(f"skipping fetch from {hostname}: dns lookup failed")
            return

        fail = False
        try:
            url = "https://" + hostname + "/api/v1/instance/peers"
            print(f"GET {url}")
            r = requests.get(url, timeout=TIMEOUT_SECS)
            count = len(r.json())
        except:
            fail = True

        if fail:
            print(f"{hostname}: api fetch failed")
            badhosts[hostname] = True
        else:
            print(f"{hostname}: api fetch got {count}")
            goodhosts[hostname] = True
            for newhn in r.json():
                if newhn is None:
                    continue
                newhn = str(newhn)
                if newhn in fetchqueue:
                    continue
                if newhn in goodhosts:
                    continue
                if newhn in badhosts:
                    continue

                if fakehostre.search(newhn):
                    print(f"skipping add of {newhn} due to re spam match")
                    continue

                if simplehostre.search(newhn):
                    print(f"got new hostname '{newhn}' from api on {hostname}")
                    fetchqueue[newhn] = True
                else:
                    print(f"got weird hostname '{newhn}' from api on {hostname}, skipping")

        writefiles()

    def writefiles():
        print(f"writing files. fetchqueue={len(fetchqueue.keys())} goodhosts={len(goodhosts.keys())} badhosts={len(badhosts.keys())}")
        gh = list(goodhosts.keys())
        gh.sort()
        bh = list(badhosts.keys())
        bh.sort()
        fq = list(fetchqueue.keys())
        fq.sort()
        with open('.goodhosts.json.tmp', 'w') as outfile:
            json.dump(gh, outfile)
        os.rename('.goodhosts.json.tmp', 'goodhosts.json')
        with open('.badhosts.json.tmp', 'w') as outfile:
            json.dump(bh, outfile)
        os.rename('.badhosts.json.tmp', 'badhosts.json')
        with open('.fetchqueue.json.tmp', 'w') as outfile:
            json.dump(fq, outfile)
        os.rename('.fetchqueue.json.tmp', 'fetchqueue.json')

    while len(fetchqueue.keys()):
        tl = list(fetchqueue.keys())
        random.shuffle(tl)
        for h in tl:
            print(f"{len(fetchqueue.keys())} hosts in fetchqueue")
            fetchnext(h)

if __name__ == "__main__":
    main()