#
# Emulab support for Rumba
#
#    Sander Vrijders  <sander.vrijders@intec.ugent.be>
#    Wouter Tavernier <wouter.tavernier@intec.ugent.be>
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
# MA  02110-1301  USA

import os
import time
import re
from ast import literal_eval

import rumba.ssh_support as ssh
from rumba.model import Testbed

import warnings
warnings.filterwarnings("ignore")

# Represents an emulab testbed info
#
# @url [string] URL of the testbed
# @image [string] specific image to use
#
class EmulabTestbed(Testbed):
    def __init__(self, exp_name, username, password = "",
                 proj_name  = "ARCFIRE", url = "wall1.ilabt.iminds.be",
                 image = "UBUNTU14-64-STD"):
        Testbed.__init__(self, exp_name, username, password, proj_name)
        self.url = url
        self.image = image

    def ops_server(self):
        '''
        Return server name of the ops-server (is testbed specific)

        @param self: testbed info

        @return: server name of the ops-server
        '''
        return 'ops.' + self.url

    def full_name(self, node_name):
        '''
        Return server name of a node

        @param node_name: name of the node
        @param self: testbed info

        @return: server name of the node
        '''
        return node_name + '.' + self.exp_name + '.' + \
            self.proj_name + '.' + self.url

    def get_experiment_list(self, project_name = None):
        '''
        Get list of made emulab experiments accessible with your credentials

        @param self: testbed info
        @param project_name: optional filter on project

        @return: list of created experiments (strings)
        '''
        cmd = '/usr/testbed/bin/sslxmlrpc_client.py -m experiment getlist'
        out = ssh.execute_command(self, self.ops_server(), cmd)

        try:
            if project_name != None:
                return  literal_eval(out)[project_name][project_name]
            else:
                return  literal_eval(out)
        except:
            return { project_name: { project_name: [] }}

    def swap_exp_in(self):
        '''
        Swaps experiment in

        @param self: testbed info
        '''
        cmd = '/usr/testbed/bin/sslxmlrpc_client.py swapexp proj=' + \
              self.proj_name + \
              ' exp=' + \
              self.exp_name + \
              ' direction=in'

        output = ssh.execute_command(self, self.ops_server(), cmd)

        return output

    def _create_experiment(self, nodes, links):
        '''
        Creates an emulab experiment

        @param self: testbed info
        @param nodes: holds the nodes in the experiment
        @param links: holds the links in the experiment
        '''
        proj_name = self.proj_name
        exp_name = self.exp_name

        exp_list = self.get_experiment_list()

        try:
            if exp_name in exp_list[proj_name][proj_name]:
                print("Experiment already exists.")
                return
        except:
            print("First experiment to be created for that project.")

        ns = self.generate_ns_script(nodes, links)
        dest_file_name = '/users/'+ self.username + \
                         '/temp_ns_file.%s.ns' % os.getpid()
        ssh.copy_file_to_testbed(self, self.ops_server(), ns, dest_file_name)

        cmd = '/usr/testbed/bin/sslxmlrpc_client.py startexp ' + \
              'batch=false wait=true proj="' + proj_name + \
              '" exp="' + exp_name + '" noswapin=true ' + \
              'nsfilepath="' + dest_file_name + '"'

        ssh.execute_command(self, self.ops_server(), cmd, time_out = None)
        ssh.execute_command(self, self.ops_server(),'rm ' + dest_file_name)
        print("New experiment succesfully created.")

    def generate_ns_script(self, nodes, p2plinks):
        '''
        Generate ns script based on network graph.
        Enables to customize default node image.

        @param nodes: holds the nodes in the experiment
        @param links: holds the links in the experiment
        @param self: testbed info

        @return: ns2 script for Emulab experiment
        '''

        ns2_script = "# ns script generated by Rumba\n"
        ns2_script += "set ns [new Simulator]\n"
        ns2_script += "source tb_compat.tcl\n"

        for node in nodes:
                ns2_script += "set " + node.name + " [$ns node]\n"
                ns2_script += "tb-set-node-os $" + node.name + " " + \
                              self.image + "\n"

        for link in p2plinks:
                ns2_script += "set " + link.name + \
                              " [$ns duplex-link $" + \
                              link.node_a.name + " $" + \
                              link.node_b.name + " 1000Mb 0ms DropTail]\n"

        ns2_script += "$ns run\n"

        return ns2_script

    def wait_until_nodes_up(self):
        '''
        Checks if nodes are up

        @param self: testbed info
        '''
        print("Waiting until all nodes are up")

        cmd = '/usr/testbed/bin/script_wrapper.py expinfo -e' + \
              self.proj_name + \
              ',' + \
              self.exp_name + \
              ' -a | grep State | cut -f2,2 -d " "'

        res = ssh.execute_command(self, self.ops_server(), cmd)
        active = False
        if res == "active":
            active = True
        while active != True:
            res = ssh.execute_command(self, self.ops_server(), cmd)
            if res == "active":
                active = True
            print("Still waiting")
            time.sleep(5)

    def complete_experiment_graph(self, nodes, p2plinks):
        '''
        Gets the interface (ethx) to link mapping

        @param self: testbed info
        @param nodes: holds the nodes in the experiment
        @param links: holds the links in the experiment
        '''

        node_full_name = self.full_name(nodes[0].name)
        cmd = 'cat /var/emulab/boot/topomap'
        topomap = ssh.execute_command(self, node_full_name, cmd)
        # Almost as ugly as yo momma
        index = topomap.rfind("# lans")
        topo_array = topomap[:index].split('\\n')[1:-1]
        # Array contains things like 'r2b1,link7:10.1.6.3 link6:10.1.5.3'
        for item in topo_array:
            item_array = re.split(',? ?', item)
            node_name = item_array[0]
            for item2 in item_array[1:]:
                item2 = item2.split(':')
                link_name = item2[0]
                link_ip = item2[1]
                for link in p2plinks:
                    if link.name == link_name:
                        if link.node_a.name == node_name:
                            link.int_a.ip = link_ip
                        elif link.node_b.name == node_name:
                            link.int_b.ip = link_ip

        for node in nodes:
            cmd = 'cat /var/emulab/boot/ifmap'
            node_full_name  = self.full_name(node.name)
            output = ssh.execute_command(self, node_full_name, cmd)
            output = re.split('\\\\n', output)
            for item in output:
                item = item.split()
                for link in p2plinks:
                    if link.node_a.name == node.name and \
                       link.int_a.ip == item[1]:
                        link.int_a.name = item[0]
                    elif link.node_b.name == node.name and \
                         link.int_b.ip == item[1]:
                        link.int_b.name =  item[0]
            node.full_name = self.full_name(node.name)

    def create_experiment(self, nodes, links):
        self._create_experiment(nodes, links)
        self.swap_exp_in()
        self.wait_until_nodes_up()
        self.complete_experiment_graph(nodes, links)