#!/usr/bin/env python
#-----------------------------------------------------------------------------
# Copyright (C) 2016, by Phil D. Howard - all other rights reserved
# 
# Permission to use, copy, modify, and/or distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
# 
# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA, OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF
# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
# 
# The author may be contacted using the short first name, middle initial,
# and last name, separated by periods, with gmail dot com as the host part
# of an email address.
#-----------------------------------------------------------------------------
# audience      linux and unix users
# script        list-instances.py
# purpose       show instances
# syntax        python list-instances.py [ region ... ]
# alternate     python list-running-instances.py [ region ... ]
# note          copy or symlink so the command for list-running-instances.py runs list-instances.py to list only running (and pending) instances
#-----------------------------------------------------------------------------
from __future__ import division, print_function
"""
show instances
"""

import botocore.session

from aws_regions     import aws_regions_list_long, aws_regions_any_to_long
from imports         import *
from multiprocessing import Pipe, Process
from os              import getpid, remove
from pickle          import dump, load
from pyutils         import eprint, plural

pipe   = None
region = None
run    = None

#-----------------------------------------------------------------------------
# function      print_instance
# purpose       print one line describing one instance
#-----------------------------------------------------------------------------
def print_instance( region, instance ):
    if instance == None:
        return None
    s = region + ' ' + instance['InstanceId']
    n = region + '_'
    if 'State' in instance:
        s += ' '
        s += instance['State']['Name']
    if 'ImageId' in instance:
        s += ' '
        s += instance['ImageId']
        n += instance['ImageId']
    if 'Placement' in instance:
        if 'AvailabilityZone' in instance['Placement']:
            s += ' '
            s += instance['Placement']['AvailabilityZone'][-1]
    if 'InstanceType' in instance:
        s += ' '
        s += instance['InstanceType']
    if 'VpcId' in instance:
        s += ' '
        s += instance['VpcId']
    if 'PublicIpAddress' in instance:
        s += ' '
        s += instance['PublicIpAddress']
    if 'PrivateIpAddress' in instance:
        s += ' ( '
        s += instance['PrivateIpAddress']
        s += ' )'
    if 'Tags' in instance:
        tags = sorted([(tag['Key'], tag['Value']) for tag in instance['Tags']],cmptag)
        for tag in tags:
            s += ' '
            s += tag[0]
            s += '='
            s += repr(tag[1])
    try:
        print( s )
    except IOError:
        pass
    return s

#-----------------------------------------------------------------------------
# function      cmptag
# purpose       compare logic for sort() so 'Name' collates lowest
#-----------------------------------------------------------------------------
def cmptag(a,b):
    if a == 'Name':
        return -1
    if b == 'Name':
        return 1
    if a < b:
        return -1
    if a > b:
        return 1
    return 0

#-----------------------------------------------------------------------------
# function    lookup
# purpose     run as a child process per region to get instance info
#             pickle the info from the describe_instances method
#             pipe this info to the parent using pickle format
# note        the pipe is inherited from the parent
#-----------------------------------------------------------------------------
def lookup():
    session = botocore.session.get_session()
    client = session.create_client( 'ec2', region_name=region )
    paginator = client.get_paginator( 'describe_instances' )
    page_iterator = paginator.paginate()
    pipe[0].close()
    for page in page_iterator:
        for resv in page[ 'Reservations' ]:
            for instance in resv[ 'Instances' ]:
                if run and 'State' in instance:
                   if instance['State']['Name'][1:] != 'unning':
                       continue
                pipe[1].send( instance )
    pipe[1].send( None )
    pipe[1].close() # send EOF
    return

#-----------------------------------------------------------------------------
# function      main
#-----------------------------------------------------------------------------
def main( args ):
    global pipe, region, run # passing as globals instead of args

    errors = 0

    # arguments are regions
    region_list = []
    
    if 'run' in args[0]:
        run = True
    else:
        run = False

#-----------------------------------------------------------------------------
    for arg in args[1:]:
        if arg in ('-r','+r','--run','++run'):
            run = True
            continue
        if arg.lower() in aws_regions_any_to_long:
            region = aws_regions_any_to_long[ arg.lower() ]
            if region in region_list:
                print( 'region', region, 'already specified', file=stderr )
                errors += 1
            else:
                region_list += [ region ]
        else:
            print( 'argument', repr(arg), 'is not a valid region', file=stderr )
            errors += 1

    if errors > 0:
        return 'aborting due to '+repr( errors )+'error'+plural( errors )

    if len( region_list ) == 0:
        region_list = list( aws_regions_list_long )

    region_list.sort()
    region_count = len( region_list )

#-----------------------------------------------------------------------------
# setup, record, and start all the processes
#-----------------------------------------------------------------------------
    plist = []
    for region in region_list:
        pipe = Pipe( False )
        process = Process( target = lookup ) # child inherits pipe and region, so no args needed.
        plist += [ ( region, process, pipe ) ]
        process.start()

#-----------------------------------------------------------------------------
# read all the results of each process.
# so what if we delay on the first ones, we have to wait on all the data.
#-----------------------------------------------------------------------------
    for this_region, this_process, this_pipe in plist:
        pipe[1].close() # close the parent copy of the send side of the pipe.
        while True:
            try:
                if print_instance( this_region, this_pipe[0].recv() ) == None: break
            except EOFError:
                break

#-----------------------------------------------------------------------------
# wait up to 6 minutes for all of them to finish
#-----------------------------------------------------------------------------
    for this_region, this_process, this_pipe in plist:
        this_process.join( 360 )

#-----------------------------------------------------------------------------
# all done
#-----------------------------------------------------------------------------
    return 0

#-----------------------------------------------------------------------------
if __name__ == '__main__':
    from sys import argv, stderr, stdout
    result = main( argv )
    stdout.flush()
    try:
        exit( int( result ) )
    except ValueError:
        print( str( result ), file=stderr )
        exit( 1 )
    except TypeError:
        if result == None:
            exit( 0 )
        exit( 254 )
    except:
        exit( 255 )

#-----------------------------------------------------------------------------
# EOF