#!/usr/bin/env python

# Copyright (c) 2014 Kungliga Tekniska Högskolan
# (KTH Royal Institute of Technology, Stockholm, Sweden).
# See LICENSE for licensing information.

import urllib2
import urllib
import json
import base64
import sys
import struct
import hashlib
import itertools
from certtools import *

baseurl = "https://127.0.0.1:8080/"
certfiles = ["testcerts/cert1.txt", "testcerts/cert2.txt",
             "testcerts/cert3.txt", "testcerts/cert4.txt",
             "testcerts/cert5.txt"]

cc1 = get_certs_from_file(certfiles[0])
cc2 = get_certs_from_file(certfiles[1])
cc3 = get_certs_from_file(certfiles[2])
cc4 = get_certs_from_file(certfiles[3])
cc5 = get_certs_from_file(certfiles[4])

failures = 0
indentation = ""

def testgroup(name):
    global indentation
    print name + ":"
    indentation = "    "

def print_error(message, *args):
    global failures, indentation
    print indentation + "ERROR:", message % args
    failures += 1

def print_success(message, *args):
    print indentation + message % args

def assert_equal(actual, expected, name, quiet=False, nodata=False):
    global failures
    if actual != expected:
        if nodata:
            print_error("%s differs", name)
        else:
            print_error("%s expected %s got %s", name, expected, actual)
    elif not quiet:
        print_success("%s was correct", name)

def print_and_check_tree_size(expected):
    global failures
    sth = get_sth(baseurl)
    try:
        check_sth_signature(baseurl, sth)
    except AssertionError, e:
        print_error("%s", e)
    except ecdsa.keys.BadSignatureError, e:
        print_error("bad STH signature")
    tree_size = sth["tree_size"]
    assert_equal(tree_size, expected, "tree size")

def do_add_chain(chain):
    global failures
    try:
        result = add_chain(baseurl, {"chain":map(base64.b64encode, chain)})
    except ValueError, e:
        print_error("%s", e)
    try:
        check_sct_signature(baseurl, chain[0], result)
    except AssertionError, e:
        print_error("%s", e)
    except ecdsa.keys.BadSignatureError, e:
        print_error("bad SCT signature")
    print_success("signature check succeeded")
    return result

def get_and_validate_proof(timestamp, chain, leaf_index, nentries):
    cert = chain[0]
    merkle_tree_leaf = pack_mtl(timestamp, cert)
    leaf_hash = get_leaf_hash(merkle_tree_leaf)
    sth = get_sth(baseurl)
    proof = get_proof_by_hash(baseurl, leaf_hash, sth["tree_size"])
    assert_equal(proof["leaf_index"], leaf_index, "leaf_index")
    assert_equal(len(proof["audit_path"]), nentries, "audit_path length")
    get_and_check_entry(timestamp, chain, leaf_index)

def get_and_check_entry(timestamp, chain, leaf_index):
    entries = get_entries(baseurl, leaf_index, leaf_index)
    assert_equal(len(entries), 1, "get_entries", quiet=True)
    fetched_entry = entries["entries"][0]
    merkle_tree_leaf = pack_mtl(timestamp, chain[0])
    leaf_input =  base64.decodestring(fetched_entry["leaf_input"])
    assert_equal(leaf_input, merkle_tree_leaf, "entry", nodata=True)
    extra_data = base64.decodestring(fetched_entry["extra_data"])
    certchain = decode_certificate_chain(extra_data)

    submittedcertchain = chain[1:]

    for (submittedcert, fetchedcert, i) in zip(submittedcertchain,
                                               certchain, itertools.count(1)):
        assert_equal(fetchedcert, submittedcert, "cert %d in chain" % (i,))

    if len(certchain) == len(submittedcertchain) + 1:
        last_issuer = get_cert_info(certs[-1])["issuer"]
        root_subject = get_cert_info(certchain[-1])["subject"]
        if last_issuer == root_subject:
            print_success("fetched chain has an appended root cert")
        else:
            print_error("fetched chain has an extra entry")
            failures += 1
    elif len(certchain) == len(submittedcertchain):
        print_success("cert chains are the same length")
    else:
        print_error("cert chain length %d expected %d or %d",
                    len(certchain),
                    len(submittedcertchain),
                    len(submittedcertchain))

print_and_check_tree_size(0)

testgroup("cert1")

result1 = do_add_chain(cc1)

print_and_check_tree_size(1)

result2 = do_add_chain(cc1)

assert_equal(result2["timestamp"], result1["timestamp"], "timestamp")

print_and_check_tree_size(1)

# TODO: add invalid cert and check that it generates an error
#       and that treesize still is 1

get_and_validate_proof(result1["timestamp"], cc1, 0, 0)

testgroup("cert2")

result3 = do_add_chain(cc2)

print_and_check_tree_size(2)

get_and_validate_proof(result1["timestamp"], cc1, 0, 1)
get_and_validate_proof(result3["timestamp"], cc2, 1, 1)

testgroup("cert3")

result4 = do_add_chain(cc3)

print_and_check_tree_size(3)

get_and_validate_proof(result1["timestamp"], cc1, 0, 2)
get_and_validate_proof(result3["timestamp"], cc2, 1, 2)
get_and_validate_proof(result4["timestamp"], cc3, 2, 1)

testgroup("cert4")

result5 = do_add_chain(cc4)

print_and_check_tree_size(4)

get_and_validate_proof(result1["timestamp"], cc1, 0, 2)
get_and_validate_proof(result3["timestamp"], cc2, 1, 2)
get_and_validate_proof(result4["timestamp"], cc3, 2, 2)
get_and_validate_proof(result5["timestamp"], cc4, 3, 2)

testgroup("cert5")

result6 = do_add_chain(cc5)

print_and_check_tree_size(5)

get_and_validate_proof(result1["timestamp"], cc1, 0, 3)
get_and_validate_proof(result3["timestamp"], cc2, 1, 3)
get_and_validate_proof(result4["timestamp"], cc3, 2, 3)
get_and_validate_proof(result5["timestamp"], cc4, 3, 3)
get_and_validate_proof(result6["timestamp"], cc5, 4, 1)

print "-------"
if failures:
    print failures, "failed tests" if failures != 1 else "failed test"
    sys.exit(1)
else:
    print "all tests succeeded"