#!/usr/bin/env python
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.

# This script exists to generate the Certificate Authority and server
# certificates used for SSL testing in Mochitest. The already generated
# certs are located at $topsrcdir/build/pgo/certs/ .

import os
import random
import re
import shutil
import subprocess
import sys

import mozinfo
from mozbuild.base import BinaryNotFoundException, MozbuildObject
from mozfile import NamedTemporaryFile, TemporaryDirectory
from mozprofile.permissions import ServerLocations

dbFiles = [
    re.compile(r"^cert[0-9]+\.db$"),
    re.compile(r"^key[0-9]+\.db$"),
    re.compile(r"^secmod\.db$"),
]


def unlinkDbFiles(path):
    for root, dirs, files in os.walk(path):
        for name in files:
            for dbFile in dbFiles:
                if dbFile.match(name) and os.path.exists(os.path.join(root, name)):
                    os.unlink(os.path.join(root, name))


def dbFilesExist(path):
    for root, dirs, files in os.walk(path):
        for name in files:
            for dbFile in dbFiles:
                if dbFile.match(name) and os.path.exists(os.path.join(root, name)):
                    return True
    return False


def runUtil(util, args, inputdata=None, outputstream=None):
    env = os.environ.copy()
    if mozinfo.os == "linux":
        pathvar = "LD_LIBRARY_PATH"
        app_path = os.path.dirname(util)
        if pathvar in env:
            env[pathvar] = "%s%s%s" % (app_path, os.pathsep, env[pathvar])
        else:
            env[pathvar] = app_path
    proc = subprocess.Popen(
        [util] + args,
        env=env,
        stdin=subprocess.PIPE if inputdata else None,
        stdout=outputstream,
        universal_newlines=True,
    )
    proc.communicate(inputdata)
    return proc.returncode


def createRandomFile(randomFile):
    for count in xrange(0, 2048):
        randomFile.write(chr(random.randint(0, 255)))


def writeCertspecForServerLocations(fd):
    locations = ServerLocations(
        os.path.join(build.topsrcdir, "build", "pgo", "server-locations.txt")
    )
    SAN = []
    for loc in [
        i for i in iter(locations) if i.scheme == "https" and "nocert" not in i.options
    ]:
        customCertOption = False
        customCertRE = re.compile(r"^cert=(?:\w+)")
        for _ in [i for i in loc.options if customCertRE.match(i)]:
            customCertOption = True
            break

        if "ipV4Address" in loc.options:
            loc.host = "ip4:" + loc.host

        if not customCertOption:
            SAN.append(loc.host)

    fd.write(
        "issuer:printableString/CN=Temporary Certificate Authority/O=Mozilla Testing/OU=Profile Guided Optimization\n"  # NOQA: E501
    )
    fd.write("subject:{}\n".format(SAN[0]))
    fd.write("extension:subjectAlternativeName:{}\n".format(",".join(SAN)))


def constructCertDatabase(build, srcDir):
    try:
        certutil = build.get_binary_path(what="certutil")
        pk12util = build.get_binary_path(what="pk12util")
    except BinaryNotFoundException as e:
        print("{}\n\n{}\n".format(e, e.help()))
        return 1
    openssl = shutil.which("openssl")
    pycert = os.path.join(build.topsrcdir, "security", "manager", "tools", "pycert.py")
    pykey = os.path.join(build.topsrcdir, "security", "manager", "tools", "pykey.py")

    with NamedTemporaryFile(mode="wt+") as pwfile, TemporaryDirectory() as pemfolder:
        pwfile.write("\n")
        pwfile.flush()

        if dbFilesExist(srcDir):
            # Make sure all DB files from src are really deleted
            unlinkDbFiles(srcDir)

        # Copy  all .certspec and .keyspec files to a temporary directory
        for root, dirs, files in os.walk(srcDir):
            for spec in [
                i for i in files if i.endswith(".certspec") or i.endswith(".keyspec")
            ]:
                shutil.copyfile(os.path.join(root, spec), os.path.join(pemfolder, spec))

        # Write a certspec for the "server-locations.txt" file to that temporary directory
        pgoserver_certspec = os.path.join(pemfolder, "pgoserver.certspec")
        if os.path.exists(pgoserver_certspec):
            raise Exception(
                "{} already exists, which isn't allowed".format(pgoserver_certspec)
            )
        with open(pgoserver_certspec, "w") as fd:
            writeCertspecForServerLocations(fd)

        # Generate certs for all certspecs
        for root, dirs, files in os.walk(pemfolder):
            for certspec in [i for i in files if i.endswith(".certspec")]:
                name = certspec.split(".certspec")[0]
                pem = os.path.join(pemfolder, "{}.cert.pem".format(name))

                print("Generating public certificate {} (pem={})".format(name, pem))

                with open(os.path.join(root, certspec), "r") as certspec_file:
                    certspec_data = certspec_file.read()
                    with open(pem, "w") as pem_file:
                        status = runUtil(
                            pycert, [], inputdata=certspec_data, outputstream=pem_file
                        )
                        if status:
                            return status

                status = runUtil(
                    certutil,
                    [
                        "-A",
                        "-n",
                        name,
                        "-t",
                        "P,,",
                        "-i",
                        pem,
                        "-d",
                        srcDir,
                        "-f",
                        pwfile.name,
                    ],
                )
                if status:
                    return status

            for keyspec in [i for i in files if i.endswith(".keyspec")]:
                parts = keyspec.split(".")
                name = parts[0]
                key_type = parts[1]
                if key_type not in ["ca", "client", "server"]:
                    raise Exception(
                        "{}: keyspec filenames must be of the form XXX.client.keyspec "
                        "or XXX.ca.keyspec (key_type={})".format(keyspec, key_type)
                    )
                key_pem = os.path.join(pemfolder, "{}.key.pem".format(name))

                print("Generating private key {} (pem={})".format(name, key_pem))

                with open(os.path.join(root, keyspec), "r") as keyspec_file:
                    keyspec_data = keyspec_file.read()
                    with open(key_pem, "w") as pem_file:
                        status = runUtil(
                            pykey, [], inputdata=keyspec_data, outputstream=pem_file
                        )
                        if status:
                            return status

                cert_pem = os.path.join(pemfolder, "{}.cert.pem".format(name))
                if not os.path.exists(cert_pem):
                    raise Exception(
                        "There has to be a corresponding certificate named {} for "
                        "the keyspec {}".format(cert_pem, keyspec)
                    )

                p12 = os.path.join(pemfolder, "{}.key.p12".format(name))
                print(
                    "Converting private key {} to PKCS12 (p12={})".format(key_pem, p12)
                )
                status = runUtil(
                    openssl,
                    [
                        "pkcs12",
                        "-export",
                        "-inkey",
                        key_pem,
                        "-in",
                        cert_pem,
                        "-name",
                        name,
                        "-out",
                        p12,
                        "-passout",
                        "file:" + pwfile.name,
                    ],
                )
                if status:
                    return status

                print("Importing private key {} to database".format(key_pem))
                status = runUtil(
                    pk12util,
                    ["-i", p12, "-d", srcDir, "-w", pwfile.name, "-k", pwfile.name],
                )
                if status:
                    return status

                if key_type == "ca":
                    shutil.copyfile(
                        cert_pem, os.path.join(srcDir, "{}.ca".format(name))
                    )
                elif key_type == "client":
                    shutil.copyfile(p12, os.path.join(srcDir, "{}.client".format(name)))
                elif key_type == "server":
                    pass  # Nothing to do for server keys
                else:
                    raise Exception(
                        "State error: Unknown keyspec key_type: {}".format(key_type)
                    )

    return 0


build = MozbuildObject.from_environment()
certdir = os.path.join(build.topsrcdir, "build", "pgo", "certs")
certificateStatus = constructCertDatabase(build, certdir)
if certificateStatus:
    print("TEST-UNEXPECTED-FAIL | SSL Server Certificate generation")
sys.exit(certificateStatus)
