#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
# Copyright (c) 2014-2015, NORDUnet A/S.
# See LICENSE for licensing information.

import sys
import urllib2
import base64
import select
from certtools import timing_point, check_sth_signature, \
     create_sth_signature, get_public_key_from_file
from mergetools import get_curpos, get_logorder, chunks, get_missingentries, \
     sendsth, hexencode, sendlog, sendentry, read_chain

def merge_dist(args, config, localconfig, sth_in):
    paths = localconfig["paths"]
    own_key = (localconfig["nodename"],
               "%s/%s-private.pem" % (paths["privatekeys"],
                                      localconfig["nodename"]))
    frontendnodes = config["frontendnodes"]
    signingnodes = config["signingnodes"]
    ctbaseurl = config["baseurl"]
    logpublickey = get_public_key_from_file(paths["logpublickey"])
    mergedb = paths["mergedb"]
    chainsdir = mergedb + "/chains"
    logorderfile = mergedb + "/logorder"
    timing = timing_point()

    logorder = get_logorder(logorderfile)
    timing_point(timing, "get logorder")

    (tree_size, root_hash, timestamp) = sth_in
    tree_head_signature = None
    for signingnode in signingnodes:
        try:
            tree_head_signature = \
              create_sth_signature(tree_size, timestamp,
                                   root_hash,
                                   "https://%s/" % signingnode["address"],
                                   key=own_key)
            break
        except urllib2.URLError, err:
            print >>sys.stderr, err
            sys.stderr.flush()
    if tree_head_signature == None:
        print >>sys.stderr, "Could not contact any signing nodes"
        sys.exit(1)

    sth = {"tree_size": tree_size, "timestamp": timestamp,
           "sha256_root_hash": base64.b64encode(root_hash),
           "tree_head_signature": base64.b64encode(tree_head_signature)}

    check_sth_signature(ctbaseurl, sth, publickey=logpublickey)

    timing_point(timing, "build sth")

    if args.timing:
        print >>sys.stderr, timing["deltatimes"]
        sys.stderr.flush()

    print hexencode(root_hash)
    sys.stdout.flush()

    for frontendnode in frontendnodes:
        nodeaddress = "https://%s/" % frontendnode["address"]
        nodename = frontendnode["name"]
        timing = timing_point()
        print >>sys.stderr, "distributing for node", nodename
        sys.stderr.flush()
        curpos = get_curpos(nodename, nodeaddress, own_key, paths)
        timing_point(timing, "get curpos")
        print >>sys.stderr, "current position", curpos
        sys.stderr.flush()
        entries = [base64.b64encode(entry) for entry in logorder[curpos:]]
        print >>sys.stderr, "sending log:",
        sys.stderr.flush()
        for chunk in chunks(entries, 1000):
            for trynumber in range(5, 0, -1):
                sendlogresult = sendlog(nodename, nodeaddress,
                                        own_key, paths,
                                        {"start": curpos, "hashes": chunk})
                if sendlogresult == None:
                    if trynumber == 1:
                        sys.exit(1)
                    select.select([], [], [], 10.0)
                    print >>sys.stderr, "tries left:", trynumber
                    sys.stderr.flush()
                    continue
                break
            if sendlogresult["result"] != "ok":
                print >>sys.stderr, "sendlog:", sendlogresult
                sys.exit(1)
            curpos += len(chunk)
            print >>sys.stderr, curpos,
            sys.stderr.flush()
        print >>sys.stderr
        timing_point(timing, "sendlog")
        print >>sys.stderr, "log sent"
        sys.stderr.flush()
        missingentries = get_missingentries(nodename, nodeaddress, own_key,
                                            paths)
        timing_point(timing, "get missing")
        print >>sys.stderr, "missing entries:", len(missingentries)
        sys.stderr.flush()
        fetched_entries = 0
        print >>sys.stderr, "fetching missing entries",
        sys.stderr.flush()
        for missingentry in missingentries:
            ehash = base64.b64decode(missingentry)
            sendentryresult = sendentry(nodename, nodeaddress, own_key, paths,
                                        read_chain(chainsdir, ehash), ehash)
            if sendentryresult["result"] != "ok":
                print >>sys.stderr, "send sth:", sendentryresult
                sys.exit(1)
            fetched_entries += 1
            if fetched_entries % 1000 == 0:
                print >>sys.stderr, fetched_entries,
                sys.stderr.flush()
        print >>sys.stderr
        sys.stderr.flush()
        timing_point(timing, "send missing")
        sendsthresult = sendsth(nodename, nodeaddress, own_key, paths, sth)
        if sendsthresult["result"] != "ok":
            print >>sys.stderr, "send sth:", sendsthresult
            sys.exit(1)
        timing_point(timing, "send sth")
        if args.timing:
            print >>sys.stderr, timing["deltatimes"]
            sys.stderr.flush()