#!/usr/local/bin/python
#
# This script deploys a cluster
# -------------------------------------------
#
# Pre-requisites
# - Python 2.7
# - SSHLibrary (pip install robotframework-sshlibrary)
# - pystache (pip install pystache)
# - argparse (pip install argparse)
#
# The input that this script will take is as follows,
#
# - A comma separated list of ip addresses/hostnames for each host on which the distribution needs to be deployed
# - The replication factor to be used
# - The ssh username/password of the remote host(s). Note that this should be the same for each host
# - The name of the template to be used.
#   Note that this template name should match the name of a template folder in the templates directory.
#   The templates directory can be found in the same directory as this script.
#
# Here are the things it will do,
#
# - Copy over a distribution of opendaylight to the remote host
# - Create a timestamped directory on the remote host
# - Unzip the distribution to the timestamped directory
# - Copy over the template substituted configuration files to the appropriate location on the remote host
# - Create a symlink to the timestamped directory
# - Start karaf
#
# -------------------------------------------------------------------------------------------------------------

import argparse
import time
import pystache
import os
import sys
import random
import re
from remote_host import RemoteHost

parser = argparse.ArgumentParser(description='Cluster Deployer')
parser.add_argument("--distribution", default="",
                    help="the absolute path of the distribution on the local host that needs to be deployed. "
                    "(Must contain version in the form: \"<#>.<#>.<#>-<name>\", e.g. 0.2.0-SNAPSHOT)",
                    required=True)
parser.add_argument("--rootdir", default="/root",
                    help="the root directory on the remote host where the distribution is to be deployed",
                    required=True)
parser.add_argument("--hosts", default="", help="a comma separated list of host names or ip addresses",
                    required=True)
parser.add_argument("--clean", action="store_true", default=False, help="clean the deployment on the remote host")
parser.add_argument("--template", default="openflow",
                    help="the name of the template to be used. "
                    "This name should match a folder in the templates directory.")
parser.add_argument("--rf", default=3, type=int,
                    help="replication factor. This is the number of replicas that should be created for each shard.")
parser.add_argument("--user", default="root", help="the SSH username for the remote host(s)")
parser.add_argument("--password", default="Ecp123", help="the SSH password for the remote host(s)")
args = parser.parse_args()


#
# The TemplateRenderer provides methods to render a template
#
class TemplateRenderer:
    def __init__(self, template):
        self.cwd = os.getcwd()
        self.template_root = self.cwd + "/templates/" + template + "/"

    def render(self, template_path, output_path, variables={}):
        with open(self.template_root + template_path, "r") as myfile:
            data = myfile.read()

        parsed = pystache.parse(u"%(data)s" % locals())
        renderer = pystache.Renderer()

        output = renderer.render(parsed, variables)

        with open(os.getcwd() + "/temp/" + output_path, "w") as myfile:
            myfile.write(output)
        return os.getcwd() + "/temp/" + output_path


#
# The array_str method takes an array of strings and formats it into a string such that
# it can be used in an akka configuration file
#
def array_str(arr):
    s = "["
    for x in range(0, len(arr)):
        s = s + '"' + arr[x] + '"'
        if x < (len(arr) - 1):
            s = s + ","
    s = s + "]"
    return s


#
# The Deployer deploys the controller to one host and configures it
#
class Deployer:
    def __init__(self, host, member_no, template, user, password, rootdir, distribution,
                 dir_name, hosts, ds_seed_nodes, rpc_seed_nodes, replicas, clean=False):
        self.host = host
        self.member_no = member_no
        self.template = template
        self.user = user
        self.password = password
        self.rootdir = rootdir
        self.clean = clean
        self.distribution = distribution
        self.dir_name = dir_name
        self.hosts = hosts
        self.ds_seed_nodes = ds_seed_nodes
        self.rpc_seed_nodes = rpc_seed_nodes
        self.replicas = replicas

    def deploy(self):
        # Determine distribution version
        distribution_name = os.path.splitext(os.path.basename(self.distribution))[0]
        distribution_ver = re.search('(\d+\.\d+\.\d+-\w+\Z)|(\d+\.\d+\.\d+-\w+)(-SR\d+\Z)|(\d+\.\d+\.\d+-\w+)(-SR\d+(\.\d+)\Z)', distribution_name)  # noqa

        if distribution_ver is None:
            print distribution_name + " is not a valid distribution version. (Must contain version in the form: \"<#>.<#>.<#>-<name>\" or \"<#>.<#>.<#>-<name>-SR<#>\" or \"<#>.<#>.<#>-<name>\", e.g. 0.2.0-SNAPSHOT)"  # noqa
            sys.exit(1)
        distribution_ver = distribution_ver.group()

        # Render all the templates
        renderer = TemplateRenderer(self.template)
        akka_conf = renderer.render(
            "akka.conf.template", "akka.conf",
            {
                "HOST": self.host,
                "MEMBER_NAME": "member-" + str(self.member_no),
                "DS_SEED_NODES": array_str(self.ds_seed_nodes),
                "RPC_SEED_NODES": array_str(self.rpc_seed_nodes)
            })
        module_shards_conf = renderer.render("module-shards.conf.template", "module-shards.conf", self.replicas)
        modules_conf = renderer.render("modules.conf.template", "modules.conf")
        features_cfg = renderer.render("org.apache.karaf.features.cfg.template",
                                       "org.apache.karaf.features.cfg",
                                       {"ODL_DISTRIBUTION": distribution_ver})
        jolokia_xml = renderer.render("jolokia.xml.template", "jolokia.xml")
        management_cfg = renderer.render("org.apache.karaf.management.cfg.template",
                                         "org.apache.karaf.management.cfg",
                                         {"HOST": self.host})

        # Connect to the remote host and start doing operations
        remote = RemoteHost(self.host, self.user, self.password, self.rootdir)
        remote.mkdir(self.dir_name)

        # Delete all the sub-directories under the deploy directory if the --clean flag is used
        if(self.clean is True):
            remote.exec_cmd("rm -rf " + self.rootdir + "/deploy/*")

        # Clean the m2 repository
        remote.exec_cmd("rm -rf " + self.rootdir + "/.m2/repository")

        # Kill the controller if it's running
        remote.kill_controller()

        # Copy the distribution to the host and unzip it
        odl_file_path = self.dir_name + "/odl.zip"
        remote.copy_file(self.distribution, odl_file_path)
        remote.exec_cmd("unzip " + odl_file_path + " -d " + self.dir_name + "/")

        # Rename the distribution directory to odl
        remote.exec_cmd("mv " + self.dir_name + "/" + distribution_name + " " + self.dir_name + "/odl")

        # Copy all the generated files to the server
        remote.mkdir(self.dir_name + "/odl/configuration/initial")
        remote.copy_file(akka_conf, self.dir_name + "/odl/configuration/initial/")
        remote.copy_file(module_shards_conf, self.dir_name + "/odl/configuration/initial/")
        remote.copy_file(modules_conf, self.dir_name + "/odl/configuration/initial/")
        remote.copy_file(features_cfg, self.dir_name + "/odl/etc/")
        remote.copy_file(jolokia_xml, self.dir_name + "/odl/deploy/")
        remote.copy_file(management_cfg, self.dir_name + "/odl/etc/")

        # Add symlink
        remote.exec_cmd("ln -sfn " + self.dir_name + " " + args.rootdir + "/deploy/current")

        # Run karaf
        remote.start_controller(self.dir_name)


def main():
    # Validate some input
    if os.path.exists(args.distribution) is False:
        print args.distribution + " is not a valid file"
        sys.exit(1)

    if os.path.exists(os.getcwd() + "/templates/" + args.template) is False:
        print args.template + " is not a valid template"

    # Prepare some 'global' variables
    hosts = args.hosts.split(",")
    time_stamp = time.time()
    dir_name = args.rootdir + "/deploy/" + str(time_stamp)
    distribution_name = os.path.splitext(os.path.basename(args.distribution))[0]  # noqa

    ds_seed_nodes = []
    rpc_seed_nodes = []
    all_replicas = []
    replicas = {}

    for x in range(0, len(hosts)):
        ds_seed_nodes.append("akka.tcp://opendaylight-cluster-data@" + hosts[x] + ":2550")
        rpc_seed_nodes.append("akka.tcp://odl-cluster-rpc@" + hosts[x] + ":2551")
        all_replicas.append("member-" + str(x + 1))

    for x in range(0, 10):
        if len(all_replicas) > args.rf:
            replicas["REPLICAS_" + str(x+1)] = array_str(random.sample(all_replicas, args.rf))
        else:
            replicas["REPLICAS_" + str(x+1)] = array_str(all_replicas)

    for x in range(0, len(hosts)):
        Deployer(hosts[x], x + 1, args.template, args.user, args.password,
                 args.rootdir, args.distribution, dir_name, hosts, ds_seed_nodes,
                 rpc_seed_nodes, replicas, args.clean).deploy()

# Run the script
main()