#!python
from __future__ import print_function

from xbow import instances
from xbow import filesystems
from xbow import pools

import xbow
import yaml
import os
import argparse

parser = argparse.ArgumentParser()
parser.add_argument('-s', '--script', help='name of provisioning script')
parser.add_argument('-n', '--n_workers', help='number of workers to launch')

args = parser.parse_args()

cfg_file = os.path.join(xbow.XBOW_CONFIGDIR, "settings.yml")

with open(cfg_file, 'r') as ymlfile:
    cfg = yaml.safe_load(ymlfile)

schedulers = instances.get_by_name(cfg['scheduler_name'])
if len(schedulers) > 1:
    print('Error - there is more than one scheduler already running with this name.')
    exit(1)

fs_id = filesystems.fs_id_from_name(cfg['shared_file_system'], 
                                   region=cfg['region'] 
                                  )
if fs_id is None:
    fs_id = filesystem.create_fs(cfg['shared_file_system'],
                                 region=cfg['region'], 
                                 efs_security_groups=cfg['efs_security_groups']
                                )
cfg['fs_id'] = fs_id
if len(schedulers) == 1:
    inst = schedulers[0]
    print('Scheduler already running, now starting workers. This may take some time...')
else:
    print("Starting the scheduler node - this may take some time...")

    user_data = '''Content-Type: multipart/mixed; boundary="//"
MIME-Version: 1.0

--//
Content-Type: text/cloud-config; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Disposition: attachment; filename="cloud-config.txt"

#cloud-config
cloud_final_modules:
- [scripts-user, always]

--//
Content-Type: text/x-shellscript; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Disposition: attachment; filename="userdata.txt"

#!/bin/bash
pip install dask distributed && sudo -u ubuntu dask-scheduler > /home/ubuntu/scheduler.log 2>&1 &
mkdir -p {mount_point}
mount -t nfs -o nfsvers=4.1,rsize=1048576,wsize=1048576,hard,timeo=600,retrans=2 {fs_id}.efs.{region}.amazonaws.com:/ {mount_point}
chmod go+rw {mount_point}
echo 'SHARED={mount_point}' >> /etc/environment

'''.format(**cfg)
    extra_data = ''
    if args.script:
        with open(args.script, 'r') as f:
            on = True
            for line in f:
                if len(line) == 0:
                    pass
                elif line[0] == '#':
                    pass
                elif line[0] == '[':
                    if '[all]' in line or '[scheduler]' in line:
                        on = True
                    elif '[workers]' in line:
                        on = False
                    else:
                        raise ValueError('Error - unrecognised command in provisioning file')
                else:
                    if on:
                        extra_data += line

    final_data = '''

--//'''
    
    user_data = user_data + extra_data + final_data
    inst = instances.create(
                            cfg['scheduler_name'],
                            image_id=cfg['image_id'],
                            instance_type=cfg['scheduler_instance_type'],
                            ec2_security_groups = cfg['ec2_security_groups'],
                            user_data=user_data
                      )
    print("Scheduler ready, now starting workers. This may take some time...")
    
    cfg['scheduler_ip_address'] = inst.private_ip_address
    user_data = '''Content-Type: multipart/mixed; boundary="//"
MIME-Version: 1.0

--//
Content-Type: text/cloud-config; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Disposition: attachment; filename="cloud-config.txt"

#cloud-config
cloud_final_modules:
- [scripts-user, always]

--//
Content-Type: text/x-shellscript; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Disposition: attachment; filename="userdata.txt"

#!/bin/bash
pip install dask distributed && sudo -u ubuntu dask-worker --local-directory /tmp/dask --nthreads 1 --nprocs 1 --worker-port 45792 {scheduler_ip_address}:8786 &
mkdir -p {mount_point}
mount -t nfs -o nfsvers=4.1,rsize=1048576,wsize=1048576,hard,timeo=600,retrans=2 {fs_id}.efs.{region}.amazonaws.com:/ {mount_point}
chmod go+rw {mount_point}
echo 'SHARED={mount_point}' >> /etc/environment

'''.format(**cfg)
    extra_data = ''
    if args.script:
        with open(args.script, 'r') as f:
            on = True
            for line in f:
                if len(line) == 0:
                    pass
                elif line[0] == '#':
                    pass
                elif line[0] == '[':
                    if '[all]' in line or '[workers]' in line:
                        on = True
                    elif '[scheduler]' in line:
                        on = False
                    else:
                        raise ValueError('Error - unrecognised command in provisioning file')
                else:
                    if on:
                        extra_data += line

if args.n_workers:
    n_workers = int(args.n_workers)
else:
    n_workers = cfg['pool_size']
user_data = user_data + extra_data + final_data
sip = pools.create_spot_pool(cfg['worker_pool_name'],
                        count=n_workers,
                        price=cfg['price'],
                        image_id=cfg['image_id'],
                        instance_type=cfg['worker_instance_type'],
                        ec2_security_groups=cfg['ec2_security_groups'],
                        user_data=user_data
                      )
print("Instance running, now waiting until xbow-cluster is accessible...")

ci = instances.ConnectedInstance(inst)
print("All ready for use")
