#!/usr/bin/env python3

# Layer index Docker setup script
#
# Copyright (C) 2018 Intel Corporation
# Author: Amber Elliot <amber.n.elliot@intel.com>
#
# Licensed under the MIT license, see COPYING.MIT for details

# This script will make a cluster of 5 containers:
#
#  - layersapp: the application
#  - layersdb: the database
#  - layersweb: NGINX web server (as a proxy and for serving static content)
#  - layerscelery: Celery (for running background jobs)
#  - layersrabbit: RabbitMQ (required by Celery)
#
# It will build and run these containers and set up the database.

import sys
import argparse
import re
import subprocess
import time
import random

def get_args():
    parser = argparse.ArgumentParser(
    description='Script sets up the Layer Index tool with Docker Containers.')
    parser.add_argument('-o', '--hostname', type=str, help='Hostname of your machine. Defaults to localhost if not set.', required=False, default = "localhost")
    parser.add_argument('-p', '--http-proxy', type=str, help='http proxy in the format http://<myproxy:port>', required=False)
    parser.add_argument('-s', '--https-proxy', type=str, help='https proxy in the format http://<myproxy:port>', required=False)
    parser.add_argument('-d', '--databasefile', type=str, help='Location of your database file to import. Must be a .sql file.', required=False)
    parser.add_argument('-m', '--portmapping', type=str, help='Port mapping in the format HOST:CONTAINER. Default is %(default)s', required=False, default='8080:80')
    args = parser.parse_args()
    port = proxymod = ""
    try:
        if args.http_proxy:
            split = args.http_proxy.split(":")
            port = split[2]
            proxymod = split[1].replace("/", "")
    except IndexError:
        raise argparse.ArgumentTypeError("http_proxy must be in format http://<myproxy:port>")


    if len(args.portmapping.split(":")) != 2:
        raise argparse.ArgumentTypeError("Port mapping must in the format HOST:CONTAINER. Ex: 8080:80")
    return args.hostname, args.http_proxy, args.https_proxy, args.databasefile, port, proxymod, args.portmapping

# Edit http_proxy and https_proxy in Dockerfile
def edit_dockerfile(http_proxy, https_proxy):
    filedata= readfile("Dockerfile")
    newlines = []
    lines = filedata.splitlines()
    for line in lines:
        if "ENV http_proxy" in line and http_proxy:
            newlines.append("ENV http_proxy " + http_proxy + "\n")
        elif "ENV https_proxy" in line and https_proxy:
            newlines.append("ENV https_proxy " + https_proxy + "\n")
        else:
            newlines.append(line + "\n")

    writefile("Dockerfile", ''.join(newlines))


# If using a proxy, add proxy values to git-proxy and uncomment proxy script in .gitconfig
def edit_gitproxy(proxymod, port):
    filedata= readfile("docker/git-proxy")
    newlines = []
    lines = filedata.splitlines()
    for line in lines:
        if "PROXY=" in line:
            newlines.append("PROXY=" + proxymod + "\n")
        elif "PORT=" in line:
            newlines.append("PORT=" + port + "\n")
        else:
            newlines.append(line + "\n")
    writefile("docker/git-proxy", ''.join(newlines))
    filedata = readfile("docker/.gitconfig")
    newdata = filedata.replace("#gitproxy", "gitproxy")
    writefile("docker/.gitconfig", newdata)


# Add hostname, secret key, db info, and email host in docker-compose.yml
def edit_dockercompose(hostname, dbpassword, secretkey, portmapping):
    filedata= readfile("docker-compose.yml")
    in_layersweb = False
    in_layersweb_ports = False
    newlines = []
    lines = filedata.splitlines()
    for line in lines:
        if in_layersweb_ports:
            format = line[0:line.find("-")].replace("#", "")
            newlines.append(format + '- "' + portmapping + '"' + "\n")
            in_layersweb_ports = False
            in_layersweb = False
        elif "layersweb:" in line:
            in_layersweb = True
            newlines.append(line + "\n")
        elif "hostname:" in line:
            format = line[0:line.find("hostname")].replace("#", "")
            newlines.append(format +"hostname: " + hostname + "\n")
        elif '- "SECRET_KEY' in line:
            format = line[0:line.find('- "SECRET_KEY')].replace("#", "")
            newlines.append(format + '- "SECRET_KEY=' + secretkey + '"\n')
        elif '- "DATABASE_PASSWORD' in line:
            format = line[0:line.find('- "DATABASE_PASSWORD')].replace("#", "")
            newlines.append(format + '- "DATABASE_PASSWORD=' + dbpassword + '"\n')
        elif '- "MYSQL_ROOT_PASSWORD' in line:
            format = line[0:line.find('- "MYSQL_ROOT_PASSWORD')].replace("#", "")
            newlines.append(format + '- "MYSQL_ROOT_PASSWORD=' + dbpassword + '"\n')
        elif "ports:" in line:
            if in_layersweb:
                in_layersweb_ports = True
            newlines.append(line + "\n")
        else:
            newlines.append(line + "\n")
    writefile("docker-compose.yml", ''.join(newlines))

def generatepasswords(passwordlength):
    return ''.join([random.SystemRandom().choice('abcdefghijklmnopqrstuvwxyz0123456789!@#%^&*-_=+') for i in range(passwordlength)])

def readfile(filename):
    f = open(filename,'r')
    filedata = f.read()
    f.close()
    return filedata

def writefile(filename, data):
    f = open(filename,'w')
    f.write(data)
    f.close()


# Generate secret key and database password
secretkey = generatepasswords(50)
dbpassword = generatepasswords(10)

## Get user arguments and modify config files
hostname, http_proxy, https_proxy, dbfile, port, proxymod, portmapping = get_args()

if http_proxy:
    edit_gitproxy(proxymod, port)
if http_proxy or https_proxy:
    edit_dockerfile(http_proxy, https_proxy)

edit_dockercompose(hostname, dbpassword, secretkey, portmapping)

## Start up containers
return_code = subprocess.call("docker-compose up -d", shell=True)
if return_code != 0:
    print("docker-compose up failed")
    sys.exit(1)

# Apply any pending layerindex migrations / initialize the database. Database might not be ready yet; have to wait then poll.
time.sleep(8)
while True:
    time.sleep(2)
    return_code = subprocess.call("docker-compose run --rm layersapp /opt/migrate.sh", shell=True)
    if return_code == 0:
        break
    else:
        print("Database server may not be ready; will try again.")

# Import the user's supplied data
if dbfile:
    return_code = subprocess.call("docker exec -i layersdb mysql -uroot -p" + dbpassword + " layersdb " + " < " + dbfile, shell=True)
    if return_code != 0:
        print("Database import failed")
        sys.exit(1)

## For a fresh database, create an admin account
print("Creating database superuser. Input user name, email, and password when prompted.")
return_code = subprocess.call("docker-compose run --rm layersapp /opt/layerindex/manage.py createsuperuser", shell=True)
if return_code != 0:
    print("Creating superuser failed")
    sys.exit(1)

## Set the volume permissions using debian:stretch since we recently fetched it
return_code = subprocess.call("docker run --rm -v layerindexweb_layersmeta:/opt/workdir debian:stretch chown 500 /opt/workdir && \
         docker run --rm -v layerindexweb_layersstatic:/usr/share/nginx/html debian:stretch chown 500 /usr/share/nginx/html", shell=True)
if return_code != 0:
    print("Setting volume permissions failed")
    sys.exit(1)

## Generate static assets. Run this command again to regenerate at any time (when static assets in the code are updated)
return_code = subprocess.call("docker-compose run --rm -e STATIC_ROOT=/usr/share/nginx/html -v layerindexweb_layersstatic:/usr/share/nginx/html layersapp /opt/layerindex/manage.py collectstatic --noinput", shell = True)
if return_code != 0:
    print("Collecting static files failed")
    sys.exit(1)

print("")
ports = portmapping.split(':')
if ports[1] == '443':
    protocol = 'https'
else:
    protocol = 'http'
print("The application should now be accessible at %s://%s:%s" % (protocol, hostname, ports[0]))