#!/usr/bin/python3 -u

import sys, os
import subprocess
import argparse
import platform
import shutil
import pathlib
import distro
import pwd
import getpass
import re

#import pymysql.cursors
#pymysql.install_as_MySQLdb

pyv=platform.python_version_tuple()

if pyv[0]!='3':
	print('Need python 3 for execute this script')
	sys.exit(1)

parser = argparse.ArgumentParser(description='Script for create a flask site.')

parser.add_argument('--domain', help='The domain where is the site', required=True)
parser.add_argument('--home_user', help='The name of the new user', required=True)
parser.add_argument('--git_url', help='Url for download the last tag of app, can be used for update app', required=True)
parser.add_argument('--user', help='The name of the domain user', required=True)
parser.add_argument('--dependencies', help='The dependencies of the flask app separated by commas', required=True)
parser.add_argument('--app_flask', help='The string type app:app for load in gunicorn', required=True)
#parser.add_argument('--port', help='The port of the gunicorn application', required=True)
parser.add_argument('--path', help='The path of the flask install')

args = parser.parse_args()

linux_distro=distro.id()

home_user=args.home_user

if home_user.find('/', -1)==-1:
    print("Error: you need backslash in home_user option")
    exit(1)

user=args.user

apache_cmd='apache2'
apachectl='apache2ctl'

if linux_distro!='debian' and linux_distro!='ubuntu':
    
    apache_cmd='httpd'
    apachectl='apachectl'
    
    if linux_distro=='rocky' or linux_distro=='fedora':
        apache_group='apache'
        
    if linux_distro=='arch':
        apache_group='http'

system_user=getpass.getuser()

if os.path.isdir(home_user):
    print("Cleaning %s directory" % home_user)
    
    if subprocess.call("sudo su %s -s /bin/bash -c 'rm -f -r %s'" % (user, home_user),  shell=True) > 0:
        print('Error: cannot clean directory {}'.format(home_user))
        sys.exit(1)

"""
if linux_distro=='debian' or linux_distro=='ubuntu':
    #libapache2-mod-wsgi-py3/
    if subprocess.call("sudo apt-get update && sudo apt-get upgrade && sudo apt-get install libapache2-mod-wsgi-py3",  shell=True) > 0:
        print('Error: cannot install mod_wsgi for apache')
        sys.exit(1)
"""

print("Creating virtualenv for the flask app...")

if subprocess.call("sudo su %s -s /bin/bash -c 'mkdir -p %s && python3 -m venv %s/venv'" % (user, home_user, home_user),  shell=True) > 0:
	print('Error: cannot install python virtualenv in {}'.format(home_user))
	sys.exit(1)

dependencies=args.dependencies

if subprocess.call("sudo su %s -s /bin/bash -c '%s/venv/bin/pip install %s flask gunicorn'" % (user, home_user, dependencies.replace(',', ' ')),  shell=True) > 0:
	print('Error: cannot install python virtualenv dependencies in {}'.format(home_user))
	sys.exit(1)

num_proc=str(os.cpu_count()*2+1)

name=os.path.basename(home_user[:-1]).strip()

#port=int(args.port)

if not re.match('\w+:\w+', args.app_flask):
    
    print('Error: define the app_flask with app:app format')
    
    sys.exit(1)

path='/'

if args.path:
    
    if args.path.find('/', -1)==-1:
        print("Error: you need backslash in path option")
        exit(1)
    
    path=args.path[:-1]
    
    full_path=args.path
    
    if path=='':
        path='/'

print("Creating the service for flask app with gunicorn...")

with open('./%s-%s.service' % (args.domain, name), 'w') as f:
    
    f.write("# Save it in /etc/systemd/system/%s-%s.service\n" % (args.domain, name))
    
    f.write("[Unit]\n")
    f.write("Description=App %s\n" % name)
    f.write("After=syslog.target\n")
    f.write("After=network.target\n")

    f.write("[Service]\n")
    f.write("Type=simple\n")
    f.write("User=%s\n" % user)
    f.write("Group=%s\n" % user)
    f.write("WorkingDirectory=%s/app\n" % home_user)
    f.write("ExecStart=%svenv/bin/gunicorn -w%s -b unix:%sgunicorn.sock --timeout 300 --error-logfile %s%s-error.log --access-logfile %s%s-access.log  --reload %s\n" % (home_user, num_proc, home_user, home_user, name, home_user, name, args.app_flask))
    f.write("Restart=always\n")
    f.write("Environment=USER=%s HOME=/home/%s\n" % (user, user))

    f.write("[Install]\n")
    f.write("WantedBy=multi-user.target\n")
    
print("Downloading application using git...")

if subprocess.call('sudo cp ./%s-%s.service /etc/systemd/system' % (args.domain, name), shell=True) > 0:
    print('Error: cannot install app service in systemd...')
    sys.exit(1)
    

if subprocess.call("sudo su %s -s /bin/bash -c 'git clone %s %sapp && cd %sapp && export GTAG=$(git describe --tags `git rev-list --tags --max-count=1`) && git checkout $GTAG -b latest-$GTAG'" % (user, args.git_url, home_user, home_user),  shell=True) > 0:
	print('Error: cannot download git packages in {}app'.format(home_user))
	sys.exit(1)
    
if path=='/':
    base_name_file='{}-001-{}.conf'.format(args.domain, name)
else:
    base_name_file='{}-000-{}.conf'.format(args.domain, name)

name_file='/home/{}/{}'.format(system_user, base_name_file)

with open(name_file, 'w') as f:
    
    f.write("ProxyPreserveHost On\n")
    f.write("ProxyRequests Off\n")
    
    f.write("<Location %s>\n" % path)
    #ProxyPass unix:/home/root/flask_rest/flaskrest.sock|http://127.0.0.1/
    f.write("ProxyPass unix:%sgunicorn.sock|http://127.0.0.1%s\n" % (home_user, full_path))
    f.write("ProxyPassReverse unix:%sgunicorn.sock|http://127.0.0.1%s\n" % (home_user, full_path))
    
    if path!='/':
        f.write("RequestHeader set SCRIPT_NAME %s\n" % path)
    
    f.write("RequestHeader set X-Forwarded-Proto http\n")
    f.write("RequestHeader set X-Forwarded-Prefix %s\n" % path)
    
    f.write("</Location>\n")
    
    if path=='/':
        f.write("<Location /.well-known/acme-challenge/>\n")
        f.write("ProxyPass !\n")
        f.write("</Location>\n")
    

print('Updating apache configuration for flask outside of htdocs...')
if subprocess.call('sudo mv {} /etc/{}/vhosts.d/extra && sudo chown root:root /etc/{}/vhosts.d/extra/{}'.format(name_file, apache_cmd, apache_cmd, base_name_file),  shell=True) > 0:
    print('Error')
    sys.exit(1)

print("Preparing apache for use gunicorn...")

if linux_distro=='debian' or linux_distro=='ubuntu':
    if subprocess.call('sudo a2enmod proxy_http', shell=True) > 0:
        print("Error: cannot enable proxy_http in apache in debian/ubuntu distro")
        sys.exit(1)

service=args.domain+'-'+name

if subprocess.call("sudo systemctl enable %s && sudo systemctl start %s  && sudo systemctl restart %s" % (service, service, apache_cmd),  shell=True) > 0:
	print("Error: cannot update and restart apache")
	sys.exit(1)

print("Flask app install successfully!")