#!/usr/bin/env python3
import sys
from sys import stdin, stdout
import socket
import sqlite3

def setupdb():
	conn = sqlite3.connect('{{ powerdns.letsencrypthandler.dbpath }}', isolation_level=None)
	conn.executescript("""
		CREATE TABLE IF NOT EXISTS challenges (
			q	TEXT	NOT NULL,
			value	TEXT,
			timestamp	DEFAULT	(strftime('%s','now'))
		)
	""")
	conn.commit()
	return conn

def get_challenge(db, path):
	c = db.cursor()
	c.execute('SELECT value FROM challenges WHERE q = ?', (path,))
	result = c.fetchone()
	if result:
		return result
	else:
		return ['NO DATA - ' + socket.gethostname()]

def add_challenge(db, path, value):
	c = db.cursor()
	c.execute('REPLACE INTO challenges (q, value) VALUES(?, ?)', (path,value,))
	db.commit()

def main_query():
	db = setupdb()
	data = stdin.readline()
	stdout.write("OK\tpdns letsencrypt handler\n")
	stdout.flush()
	while True:
		data = stdin.readline().strip()
		kind, qname, qclass, qtype, id, ip = data.split("\t")
		if qtype == "SOA":
			stdout.write("DATA\t" + qname + "\t" + qclass + "\t" + qtype + "\t300\t" + id + "\t")
			stdout.write("example.com. example.example.com. 1 1d 2h 4w 1h\n")
		else:
			for i in get_challenge(db, qname.lower()):
				stdout.write("DATA\t" + qname + "\t" + qclass + "\tTXT\t1\t" + id + '\t"' + i + '"\n')
		stdout.write("LOG\tletsencrypt pipe handler got query: '" + data + "'\n")
		stdout.write("END\n")
		stdout.flush()

def main_add_challenge():
	db = setupdb()
	add_challenge(db ,sys.argv[1], sys.argv[2])

def main():
	if len(sys.argv) == 3:
		main_add_challenge()
	else:
		main_query()

if __name__ == '__main__':
	main()