#!/usr/bin/python2.7

import md5
import os
import urllib2
import json
import sys
import time
import config

DRAIN = True
TERMINATE = True

SHUTDOWN_MINUTES = 5
sendcommand_secret = config.get('SENDCOMMAND_SECRET')
leaderboard_address = config.get('LEADERBOARD_ADDRESS_AND_PORT')
sendcommand_url = 'http://%s/api/sendcommand' % leaderboard_address
serverinfo_url = 'http://%s/api/serverinfo' % leaderboard_address
project_name = config.get('PROJECT_NAME')

#SHUTDOWN_MINUTES = 5
#sendcommand_url = 'http://localhost:8080/api/sendcommand'
#serverinfo_url = 'http://localhost:8080/api/serverinfo'

def get_serverinfo():
    opener = urllib2.build_opener(urllib2.HTTPHandler)
    request = urllib2.Request(serverinfo_url)
    request.get_method = lambda: 'GET'
    try:
        response = opener.open(request).read()
    except urllib2.HTTPError, e:
        print 'Error %d, %s' % (e.code, e.read())
        return None
    return json.loads(response)

def get_updated_info(info):
    serverinfo = get_serverinfo()
    for i in serverinfo['infos']:
        if i['name'] == info['name'] and i['start_utc'] == info['start_utc']:
            return i
    return None

def which_servers(serverinfo):
    if len(serverinfo['infos']) == 0:
        return None
    index = 0
    for info in serverinfo['infos']:
        print 'Server #%d. Name: %s' % (index, info['name'])
        for key in sorted(info.keys()):
            if key == 'name':
                continue
            print '    %s: %s' % (key, info[key])
        index = index + 1

    info = None
    while True:
        try:
            ans = raw_input('Which server number to drain and delete? ')
            index = int(ans)
            if index >= 0 and index < len(serverinfo['infos']):
                info = serverinfo['infos'][index]
                break
            print 'Incorrect server number. Try again.'
        except ValueError:
            print 'Not a number. Try again.'

    join_info = None
    while True:
        try:
            ans = raw_input('Which server number should players join (-1 for none)? ')
            index = int(ans)
            if index >= 0 and index < len(serverinfo['infos']):
                join_info = serverinfo['infos'][index]
                break
            if index == -1:
                join_info = None
                break
            print 'Incorrect server number. Try again.'
        except ValueError:
            print 'Not a number. Try again.'

    return info, join_info

def ask_continue(server_name, join_server, shutdown_count, player_count):
    print 'PLEASE VERIFY:'
    print '1. You wish to drain and delete server %s.' % server_name
    print '2. You wish to start this process once the player count reaches <= %d.' % player_count
    if join_server:
        print '3. Once reached, remaining players will receive a message to join server %s.' % join_server
    else:
        print '3. Once reached, remaining players will receive a warning message every minute.'
    print '4. The server will be deleted when the user count goes to zero or after %d minutes.' % shutdown_count

    while True:
        yesno = raw_input('Would you like to continue? (y/n) ')
        if len(yesno) < 1:
            continue
        if yesno[0] == 'n' or yesno[0] == 'N':
            return False
        if yesno[0] == 'y' or yesno[0] == 'Y':
            return True

def ask_player_count(server_name, info):
    print '%s currently has a player count of %d.' % (server_name, info['player_count'])
    while True:
        s = raw_input('What player count should trigger the drain-delete process? ')
        try:
            return int(s)
        except ValueError:
            print '%s is not a number. Try again.' % s

def wait_player_count(server_name, info, player_count):
    while True:
        print '%s current player count: %d. Trigger: %d' % \
                (server_name, info['player_count'], player_count)
        if info['player_count'] <= player_count:
            return
        time.sleep(60)
        info = get_updated_info(info)

def send_command(o):
    j = json.dumps(o)
    m = md5.new(j + sendcommand_secret)
    body = m.hexdigest() + j
    opener = urllib2.build_opener(urllib2.HTTPHandler)
    request = urllib2.Request(sendcommand_url, data=body)
    request.add_header('Content-Type', 'binary/octet-stream')
    request.add_header('Content-Length', len(body))
    request.get_method = lambda: 'POST'
    try:
        response = opener.open(request).read()
        return True
    except urllib2.HTTPError, e:
        print 'error %d, %s' % (e.code, e.read())
        return False

def drain_wait(info):
    o = dict(info=dict(name=info['name'], start_utc=info['start_utc']),
            command=dict(command='drain'))
    print 'Sending drain command.'
    if not send_command(o):
        return False
    while True:
        print 'Waiting for drain confirmation.'
        new_info = get_updated_info(info)
        if not new_info:
            return False
        if new_info['status'] == 'drain':
            print 'Drain confirmed.'
            return True
        time.sleep(30)

def send_shutdown_message(info, join_server, shutdown_count):
    if join_server:
        message = 'Shutdown in %d minutes. Join server %s now!' % \
                (shutdown_count, join_server)
    else:
        message = 'Shutdown in %d minutes.' % shutdown_count
    o = dict(info=dict(name=info['name'], start_utc=info['start_utc']),
            command=dict(command='chat', name='Admin', message=message))
    print 'Sending: %s: %s' %  (o['command']['name'],
            o['command']['message'])
    return send_command(o)

def main():
    print "NOTE: Before continuing ensure these steps have been taken:"
    print "1. Install gcloud from here if not already installed:"
    print "   https://cloud.google.com/sdk/"
    print "2. If already installed ensure it is up to date:"
    print "   $ gcloud components update"
    print "3. Authenicate:"
    print "   $ gcloud auth login"
    print "4. Select the proper project:"
    print "   $ gcloud config set project %s" % project_name

    serverinfo = get_serverinfo()
    if not serverinfo:
        print 'could not get serverinfo.'
        sys.exit(1)

    info, join_info = which_servers(serverinfo)
    if not info:
        print 'no server selected.'
        sys.exit(1)
    server_name = '%s (start_utc: %s)' % (info['name'], info['start_utc'])
    join_server = join_info['name'] if join_info else None

    player_count = ask_player_count(server_name, info)
    shutdown_count = SHUTDOWN_MINUTES
    if not ask_continue(server_name, join_server, shutdown_count, player_count):
        print 'no action taken.'
        sys.exit(1)
  
    wait_player_count(server_name, info, player_count)

    if DRAIN: 
        print 'Setting %s to drain mode. Waiting for confirmation.' % server_name
        if not drain_wait(info):
            print 'could not set %s into drain mode. no action taken.' % server_name
            sys.exit(1)

    while shutdown_count != -1:
        new_info = get_updated_info(info)
        print 'players: %d' % new_info['player_count']
        if new_info['player_count'] == 0:
            break
        send_shutdown_message(info, join_server, shutdown_count)
        shutdown_count = shutdown_count - 1
        time.sleep(60)

    print 'deleting: %s instance name: %s' % (server_name, info['instance_name'])

    if TERMINATE:
        sys.exit(os.system('gcloud compute instances delete "%s" --quiet --zone us-central1-a' % (info['instance_name'])))

    sys.exit(0)

if __name__ == '__main__':
    main()