#!/usr/bin/python3
# Prepare an Azure provider account for CycleCloud usage.
import os
import argparse
import json
import re
import random
import platform
from string import ascii_uppercase, ascii_lowercase, digits
import subprocess
from subprocess import CalledProcessError, check_output
from os import path, listdir, chdir, fdopen, remove
from urllib.request import urlopen, Request
from shutil import rmtree, copy2, move
from tempfile import mkstemp, mkdtemp
from time import sleep


tmpdir = mkdtemp()
print("Creating temp directory {} for installing CycleCloud".format(tmpdir))
cycle_root = "/opt/cycle_server"
cs_cmd = cycle_root + "/cycle_server"


def clean_up():
    rmtree(tmpdir)

def _catch_sys_error(cmd_list):
    try:
        output = check_output(cmd_list)
        print(cmd_list)
        print(output)
        return output
    except CalledProcessError as e:
        print("Error with cmd: %s" % e.cmd)
        print("Output: %s" % e.output)
        raise

def create_user(username):
    import pwd
    try:
        pwd.getpwnam(username)
    except KeyError:
        print('Creating user {}'.format(username))
        _catch_sys_error(["useradd", "-m", "-d", "/home/{}".format(username), username])
    _catch_sys_error(["chown", "-R", username + ":" + username, "/home/{}".format(username)])

def create_keypair(username, public_key=None):
    if not os.path.isdir("/home/{}/.ssh".format(username)):
        _catch_sys_error(["mkdir", "-p", "/home/{}/.ssh".format(username)])
    public_key_file  = "/home/{}/.ssh/id_rsa.pub".format(username)
    if not os.path.exists(public_key_file):
        if public_key:
            with open(public_key_file, 'w') as pubkeyfile:
                pubkeyfile.write(public_key)
                pubkeyfile.write("\n")
        else:
            _catch_sys_error(["ssh-keygen", "-f", "/home/{}/.ssh/id_rsa".format(username), "-N", ""])
            with open(public_key_file, 'r') as pubkeyfile:
                public_key = pubkeyfile.read()

    authorized_key_file = "/home/{}/.ssh/authorized_keys".format(username)
    authorized_keys = ""
    if os.path.exists(authorized_key_file):
        with open(authorized_key_file, 'r') as authkeyfile:
            authorized_keys = authkeyfile.read()
    if public_key not in authorized_keys:
        with open(authorized_key_file, 'w') as authkeyfile:
            authkeyfile.write(public_key)
            authkeyfile.write("\n")
    _catch_sys_error(["chown", "-R", username + ":" + username, "/home/{}".format(username)])
    return public_key

def create_user_credential(username, public_key=None):
    create_user(username)    
    public_key = create_keypair(username, public_key)

    credential_record = {
        "PublicKey": public_key,
        "AdType": "Credential",
        "CredentialType": "PublicKey",
        "Name": username + "/public"
    }
    credential_data_file = os.path.join(tmpdir, "credential.json")
    print("Creating cred file: {}".format(credential_data_file))
    with open(credential_data_file, 'w') as fp:
        json.dump(credential_record, fp)

    config_path = os.path.join(cycle_root, "config/data/")
    print("Copying config to {}".format(config_path))
    copy2(credential_data_file, config_path)

def generate_password_string():
    random_pw_chars = ([random.choice(ascii_lowercase) for _ in range(20)] +
                        [random.choice(ascii_uppercase) for _ in range(20)] +
                        [random.choice(digits) for _ in range(10)])
    random.shuffle(random_pw_chars)
    return ''.join(random_pw_chars)

def reset_cyclecloud_pw(username):

    reset_pw = subprocess.Popen( [cs_cmd, "reset_access", username],
                                stdin=subprocess.PIPE,
                                stdout=subprocess.PIPE,
                                stderr=subprocess.PIPE, )
    reset_out, reset_err = reset_pw.communicate( b"yes\n" )
    print(reset_out)
    if reset_err:
        print("Password reset error: %s" % (reset_err))
    out_split = reset_out.rsplit(None, 1)
    pw = out_split.pop().decode("utf-8")
    print("Disabling forced password reseet for {}".format(username))
    update_cmd = 'update AuthenticatedUser set ForcePasswordReset = false where Name=="%s"' % (username)
    _catch_sys_error([cs_cmd, 'execute', update_cmd])
    return pw 

  
def cyclecloud_account_setup(vm_metadata, use_managed_identity, tenant_id, application_id, application_secret,
                             admin_user, azure_cloud, accept_terms, password, storageAccount, no_default_account, 
                             webserver_port):

    print("Setting up azure account in CycleCloud and initializing cyclecloud CLI")

    if not accept_terms:
        print("Accept terms was FALSE !!!!!  Over-riding for now...")
        accept_terms = True

    # if path.isfile(cycle_root + "/config/data/account_data.json.imported"):
    #     print 'Azure account is already configured in CycleCloud. Skipping...'
    #     return

    subscription_id = vm_metadata["compute"]["subscriptionId"]
    location = vm_metadata["compute"]["location"]
    resource_group = vm_metadata["compute"]["resourceGroupName"]

    random_suffix = ''.join(random.SystemRandom().choice(
        ascii_lowercase) for _ in range(14))

    cyclecloud_admin_pw = ""
    if password:
        print('Password specified, using it as the admin password')
        cyclecloud_admin_pw = password
    else:
        cyclecloud_admin_pw = generate_password_string()

    if storageAccount:
        print('Storage account specified, using it as the default locker')
        storage_account_name = storageAccount
    else:
        storage_account_name = 'cyclecloud{}'.format(random_suffix)

    azure_data = {
        "Environment": azure_cloud,
        "AzureRMUseManagedIdentity": use_managed_identity,
        "AzureResourceGroup": resource_group,
        "AzureRMApplicationId": application_id,
        "AzureRMApplicationSecret": application_secret,
        "AzureRMSubscriptionId": subscription_id,
        "AzureRMTenantId": tenant_id,
        "DefaultAccount": True,
        "Location": location,
        "Name": "azure",
        "Provider": "azure",
        "ProviderId": subscription_id,
        "RMStorageAccount": storage_account_name,
        "RMStorageContainer": "cyclecloud"
    }
    distribution_method ={
        "Category": "system",
        "Status": "internal",
        "AdType": "Application.Setting",
        "Description": "CycleCloud distribution method e.g. marketplace, container, manual.",
        "Value": "manual",
        "Name": "distribution_method"
    }
    if use_managed_identity:
        azure_data["AzureRMUseManagedIdentity"] = True

    app_setting_installation = {
        "AdType": "Application.Setting",
        "Name": "cycleserver.installation.complete",
        "Value": True
    }
    initial_user = {
        "AdType": "Application.Setting",
        "Name": "cycleserver.installation.initial_user",
        "Value": admin_user
    }
    account_data = [
        initial_user,
        distribution_method,
        app_setting_installation
    ]

    if accept_terms:
        # Terms accepted, auto-create login user account as well
        login_user = {
            "AdType": "AuthenticatedUser",
            "Name": admin_user,
            "RawPassword": cyclecloud_admin_pw,
            "Superuser": True
        }
        account_data.append(login_user)

    account_data_file = tmpdir + "/account_data.json"

    with open(account_data_file, 'w') as fp:
        json.dump(account_data, fp)

    copy2(account_data_file, cycle_root + "/config/data/")
    sleep(5)

    if not accept_terms:
        # reset the installation status so the splash screen re-appears
        print("Resetting installation")
        sql_statement = 'update Application.Setting set Value = false where name ==\"cycleserver.installation.complete\"'
        _catch_sys_error(
            ["/opt/cycle_server/cycle_server", "execute", sql_statement])

    # If using a random password, we need to reset it on each container restart (since we regenerated it above)
    # But do is AFTER user is created in CC
    if not password:
        cyclecloud_admin_pw = reset_cyclecloud_pw(admin_user)
    initialize_cyclecloud_cli(admin_user, cyclecloud_admin_pw, webserver_port)

    if no_default_account:
        print("Skipping default account creation (--noDefaultAccount).") 
    else:
        output =  _catch_sys_error(["/usr/local/bin/cyclecloud", "account", "show", "azure"])
        if 'Credentials: azure' in str(output):
            print("Account \"azure\" already exists.   Skipping account setup...")
        else:
            azure_data_file = tmpdir + "/azure_data.json"
            with open(azure_data_file, 'w') as fp:
                json.dump(azure_data, fp)

            print("CycleCloud account data:")
            print(json.dumps(azure_data))

            # wait until Managed Identity is ready for use before creating the Account
            if use_managed_identity:
                get_vm_managed_identity()

            # create the cloud provide account
            print("Registering Azure subscription in CycleCloud")
            _catch_sys_error(["/usr/local/bin/cyclecloud", "account",
                            "create", "-f", azure_data_file])


def initialize_cyclecloud_cli(admin_user, cyclecloud_admin_pw, webserver_port):
    print("Setting up azure account in CycleCloud and initializing cyclecloud CLI")

    # wait for the data to be imported
    password_flag = ("--password=%s" % cyclecloud_admin_pw)

    print("Initializing cylcecloud CLI")
    _catch_sys_error(["/usr/local/bin/cyclecloud", "initialize", "--loglevel=debug", "--batch", "--force",
                      "--url=https://localhost:{}".format(webserver_port), "--verify-ssl=false", "--username=%s" % admin_user, password_flag])


def letsEncrypt(fqdn):
    sleep(60)
    try:
        cmd_list = [cs_cmd, "keystore", "automatic", "--accept-terms", fqdn]
        output = check_output(cmd_list)
        print(cmd_list)
        print(output)
    except CalledProcessError as e:
        print("Error getting SSL cert from Lets Encrypt")
        print("Proceeding with self-signed cert")


def get_vm_metadata():
    metadata_url = "http://169.254.169.254/metadata/instance?api-version=2017-08-01"
    metadata_req = Request(metadata_url, headers={"Metadata": True})

    for _ in range(30):
        print("Fetching metadata")
        metadata_response = urlopen(metadata_req, timeout=2)

        try:
            return json.load(metadata_response)
        except ValueError as e:
            print("Failed to get metadata %s" % e)
            print("    Retrying")
            sleep(2)
            continue
        except:
            print("Unable to obtain metadata after 30 tries")
            raise

def get_vm_managed_identity():
    # Managed Identity may  not be available immediately at VM startup...
    # Test/Pause/Retry to see if it gets assigned
    metadata_url = 'http://169.254.169.254/metadata/identity/oauth2/token?api-version=2018-02-01&resource=https://management.azure.com/'
    metadata_req = Request(metadata_url, headers={"Metadata": True})

    for _ in range(30):
        print("Fetching managed identity")
        metadata_response = urlopen(metadata_req, timeout=2)

        try:
            return json.load(metadata_response)
        except ValueError as e:
            print("Failed to get managed identity %s" % e)
            print("    Retrying")
            sleep(10)
            continue
        except:
            print("Unable to obtain managed identity after 30 tries")
            raise    

def start_cc():
    import glob
    import subprocess
    print("(Re-)Starting CycleCloud server")
    _catch_sys_error([cs_cmd, "stop"])
    if glob.glob("/opt/cycle_server/data/ads/corrupt*") or glob.glob("/opt/cycle_server/data/ads/*logfile_failure"):
        print("WARNING: Corrupted datastore masterlog detected.   Restoring from last backup...")
        if not glob.glob("/opt/cycle_server/data/backups/backup-*"):
            raise Exception("ERROR: No backups found, but master.logfile is corrupt!")
        try:
            yes = subprocess.Popen(['echo', 'yes'], stdout=subprocess.PIPE)
            output = subprocess.check_output(['/opt/cycle_server/util/restore.sh'], stdin=yes.stdout)
            yes.wait()
            print(output)
        except CalledProcessError as e:
            print("Error with cmd: %s" % e.cmd)
            print("Output: %s" % e.output)
            raise
    
    _catch_sys_error([cs_cmd, "start"])

    # Retry await_startup in case it takes much longer than expected 
    # (this is common in local testing with limited compute resources)
    max_tries = 3
    started = False
    while not started:
        try:
            max_tries -= 1
            _catch_sys_error([cs_cmd, "await_startup"])
            started = True
        except:
            if max_tries >  0:
                print("Retrying...")
            else:
                raise 


def modify_cs_config(options):
    print("Editing CycleCloud server system properties file")
    # modify the CS config files
    cs_config_file = cycle_root + "/config/cycle_server.properties"

    fh, tmp_cs_config_file = mkstemp()
    with fdopen(fh, 'w') as new_config:
        with open(cs_config_file) as cs_config:
            for line in cs_config:
                if line.startswith('webServerMaxHeapSize='):
                    new_config.write('webServerMaxHeapSize={}\n'.format(options['webServerMaxHeapSize']))
                elif line.startswith('webServerPort='):
                    new_config.write('webServerPort={}\n'.format(options['webServerPort']))
                elif line.startswith('webServerSslPort='):
                    new_config.write('webServerSslPort={}\n'.format(options['webServerSslPort']))
                elif line.startswith('webServerClusterPort'):
                    new_config.write('webServerClusterPort={}\n'.format(options['webServerClusterPort']))
                elif line.startswith('webServerEnableHttps='):
                    new_config.write('webServerEnableHttps={}\n'.format(str(options['webServerEnableHttps']).lower()))
                elif line.startswith('webServerHostname'):
                    # This isn't generally a default setting, so set it below
                    continue
                else:
                    new_config.write(line)

            if 'webServerHostname' in options and options['webServerHostname']:
                new_config.write('webServerHostname={}\n'.format(options['webServerHostname']))

    remove(cs_config_file)
    move(tmp_cs_config_file, cs_config_file)

    #Ensure that the files are created by the cycleserver service user
    _catch_sys_error(["chown", "-R", "cycle_server.", cycle_root])

def install_cc_cli():
    # CLI comes with an install script but that installation is user specific
    # rather than system wide.
    # Downloading and installing pip, then using that to install the CLIs
    # from source.
    if os.path.exists("/usr/local/bin/cyclecloud"):
        print("CycleCloud CLI already installed.")
        return

    print("Unzip and install CLI")
    chdir(tmpdir)
    _catch_sys_error(["unzip", "/opt/cycle_server/tools/cyclecloud-cli.zip"])
    for cli_install_dir in listdir("."):
        if path.isdir(cli_install_dir) and re.match("cyclecloud-cli-installer", cli_install_dir):
            print("Found CLI install DIR %s" % cli_install_dir)
            chdir(cli_install_dir)
            _catch_sys_error(["./install.sh", "--system"])


def already_installed():
    print("Checking for existing Azure CycleCloud install")
    return os.path.exists("/opt/cycle_server/cycle_server")

def download_install_cc():
    print("Installing Azure CycleCloud server")

    if "ubuntu" in str(platform.platform()).lower():
        _catch_sys_error(["apt", "install", "-y", "cyclecloud8"])
    else:
        _catch_sys_error(["yum", "install", "-y", "cyclecloud8"])

def configure_msft_repos():
    if "ubuntu" in str(platform.platform()).lower():
        configure_msft_apt_repos()
    else:
        configure_msft_yum_repos()

def configure_msft_apt_repos():
    print("Configuring Microsoft apt repository for CycleCloud install")
    _catch_sys_error(
        ["wget", "-qO", "-", "https://packages.microsoft.com/keys/microsoft.asc", "|", "apt-key", "add", "-"])
    
    lsb_release = _catch_sys_error(["lsb_release", "-cs"])
    with open('/etc/apt/sources.list.d/azure-cli.list', 'w') as f:
        f.write("deb [arch=amd64] https://packages.microsoft.com/repos/azure-cli/ {} main".format(lsb_release))

    with open('/etc/apt/sources.list.d/cyclecloud.list', 'w') as f:
        f.write("deb [arch=amd64] https://packages.microsoft.com/repos/cyclecloud {} main".format(lsb_release))
    _catch_sys_error(["apt", "-y", "update"])

def configure_msft_yum_repos():
    print("Configuring Microsoft yum repository for CycleCloud install")
    _catch_sys_error(
        ["rpm", "--import", "https://packages.microsoft.com/keys/microsoft.asc"])

    with open('/etc/yum.repos.d/cyclecloud.repo', 'w') as f:
        f.write("""\
[cyclecloud]
name=cyclecloud
baseurl=https://packages.microsoft.com/yumrepos/cyclecloud
gpgcheck=1
gpgkey=https://packages.microsoft.com/keys/microsoft.asc
""")

    with open('/etc/yum.repos.d/azure-cli.repo', 'w') as f:
        f.write("""\
[azure-cli]
name=Azure CLI
baseurl=https://packages.microsoft.com/yumrepos/azure-cli
enabled=1
gpgcheck=1
gpgkey=https://packages.microsoft.com/keys/microsoft.asc      
""")


def install_pre_req():
    print("Installing pre-requisites for CycleCloud server")

    # not strictly needed, but it's useful to have the AZ CLI
    # Taken from https://docs.microsoft.com/en-us/cli/azure/install-azure-cli-yum?view=azure-cli-latest

    if "ubuntu" in str(platform.platform()).lower():
        _catch_sys_error(["apt", "install", "-y", "openjdk-8-jre-headless"])
        _catch_sys_error(["apt", "install", "-y", "azure-cli"])
    else:
        _catch_sys_error(["yum", "install", "-y", "java-1.8.0-openjdk-headless"])
        _catch_sys_error(["yum", "install", "-y", "azure-cli"])


def main():

    parser = argparse.ArgumentParser(description="usage: %prog [options]")

    parser.add_argument("--azureSovereignCloud",
                        dest="azureSovereignCloud",
                        default="public",
                        help="Azure Region [china|germany|public|usgov]")

    parser.add_argument("--tenantId",
                        dest="tenantId",
                        help="Tenant ID of the Azure subscription")

    parser.add_argument("--applicationId",
                        dest="applicationId",
                        help="Application ID of the Service Principal")

    parser.add_argument("--applicationSecret",
                        dest="applicationSecret",
                        help="Application Secret of the Service Principal")

    parser.add_argument("--username",
                        dest="username",
                        default="cc_admin",
                        help="The local admin user for the CycleCloud VM")

    parser.add_argument("--hostname",
                        dest="hostname",
                        help="The short public hostname assigned to this VM (or public IP), used for LetsEncrypt")

    parser.add_argument("--acceptTerms",
                        dest="acceptTerms",
                        action="store_true",
                        help="Accept Cyclecloud terms and do a silent install")

    parser.add_argument("--useLetsEncrypt",
                        dest="useLetsEncrypt",
                        action="store_true",
                        help="Automatically fetch certificate from Let's Encrypt.  (Only suitable for installations with public IP.)")

    parser.add_argument("--useManagedIdentity",
                        dest="useManagedIdentity",
                        action="store_true",
                        help="Use the first assigned Managed Identity rather than a Service Principle for the default account")

    parser.add_argument("--dryrun",
                        dest="dryrun",
                        action="store_true",
                        help="Allow local testing outside Azure Docker")

    parser.add_argument("--password",
                        dest="password",
                        default="",
                        help="The password for the CycleCloud UI user")

    parser.add_argument("--publickey",
                        dest="publickey",
                        help="The public ssh key for the CycleCloud UI user")

    parser.add_argument("--storageAccount",
                        dest="storageAccount",
                        help="The storage account to use as a CycleCloud locker")

    parser.add_argument("--resourceGroup",
                        dest="resourceGroup",
                        help="The resource group for CycleCloud cluster resources.  Resource Group must already exist.  (Default: same RG as CycleCloud)")

    parser.add_argument("--noDefaultAccount",
                        dest="no_default_account",
                        action="store_true",
                        help="Do not attempt to configure a default CycleCloud Account (useful for CycleClouds managing other subscriptions)")
                    
    parser.add_argument("--webServerMaxHeapSize",
                        dest="webServerMaxHeapSize",
                        default='4096M',
                        help="CycleCloud max heap")

    parser.add_argument("--webServerPort",
                        dest="webServerPort",
                        default=8080,
                        help="CycleCloud front-end HTTP port")

    parser.add_argument("--webServerSslPort",
                        dest="webServerSslPort",
                        default=8443,
                        help="CycleCloud front-end HTTPS port")

    parser.add_argument("--webServerClusterPort",
                        dest="webServerClusterPort",
                        default=9443,
                        help="CycleCloud cluster/back-end HTTPS port")

    parser.add_argument("--webServerHostname",
                        dest="webServerHostname",
                        default="",
                        help="Over-ride CycleCloud hostname for cluster/back-end connections")

    args = parser.parse_args()

    print("Debugging arguments: %s" % args)

    if not already_installed():
        configure_msft_repos()
        install_pre_req()
        download_install_cc()
        modify_cs_config(options = {'webServerMaxHeapSize': args.webServerMaxHeapSize,
                                    'webServerPort': args.webServerPort,
                                    'webServerSslPort': args.webServerSslPort,
                                    'webServerClusterPort': args.webServerClusterPort,
                                    'webServerEnableHttps': True,
                                    'webServerHostname': args.webServerHostname})

    start_cc()

    install_cc_cli()

    if not args.dryrun:
        vm_metadata = get_vm_metadata()
    else:
        vm_metadata = {"compute": {
            "subscriptionId": "1234-50-679890",
            "location": "dryrun",
            "resourceGroupName": "dryrun-rg"}}

    if args.resourceGroup:
        print("CycleCloud created in resource group: %s" % vm_metadata["compute"]["resourceGroupName"])
        print("Cluster resources will be created in resource group: %s" %  args.resourceGroup)
        vm_metadata["compute"]["resourceGroupName"] = args.resourceGroup

    cyclecloud_account_setup(vm_metadata, args.useManagedIdentity, args.tenantId, args.applicationId,
                             args.applicationSecret, args.username, args.azureSovereignCloud,
                             args.acceptTerms, args.password, args.storageAccount, 
                             args.no_default_account, args.webServerSslPort)

    if args.useLetsEncrypt:
        letsEncrypt(args.hostname)

    #  Create user requires root privileges
    # create_user_credential(args.username, args.publickey)

    clean_up()


if __name__ == "__main__":
    try:
        main()
    except:
        print("Deployment failed...")
        raise