#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""
    openslides.main
    ~~~~~~~~~~~~~~~

    Main script to start and set up OpenSlides.

    :copyright: 2011, 2012 by OpenSlides team, see AUTHORS.
    :license: GNU GPL, see LICENSE for more details.
"""

# for python 2.5 support
from __future__ import with_statement

import os
import sys
import optparse
import socket
import time
import threading
import base64
import webbrowser

import django.conf
from django.core.management import execute_from_command_line

CONFIG_TEMPLATE = """
from openslides.openslides_settings import *

# Use 'DEBUG = True' to get more details for server errors
# (Default for relaeses: 'False')
DEBUG = False
TEMPLATE_DEBUG = DEBUG

DBPATH = %(dbpath)r

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': DBPATH,
        'USER': '',
        'PASSWORD': '',
        'HOST': '',
        'PORT': '',
    }
}

# Set timezone
TIME_ZONE = 'Europe/Berlin'

# Make this unique, and don't share it with anybody.
SECRET_KEY = %(default_key)r

# Add OpenSlides plugins to this list (see example entry in comment)
INSTALLED_PLUGINS = (
#    'pluginname',
)

INSTALLED_APPS += INSTALLED_PLUGINS
"""

KEY_LENGTH = 30


def main(argv=None):
    if argv is None:
        argv = sys.argv[1:]

    parser = optparse.OptionParser(
        description="Run openslides using django's builtin webserver")
    parser.add_option("-a", "--address", help="IP Address to listen on")
    parser.add_option("-p", "--port", type="int", help="Port to listen on")
    parser.add_option(
        "--syncdb", action="store_true",
        help="Update/create database before starting the server")
    parser.add_option(
        "--reset-admin", action="store_true",
        help="Make sure the user 'admin' exists and uses 'admin' as password")
    parser.add_option("-s", "--settings", help="Path to the setting.")
    parser.add_option(
        "--no-reload", action="store_true", help="Do not reload the development server")

    opts, args = parser.parse_args(argv)
    if args:
        sys.stderr.write("This command does not take arguments!\n\n")
        parser.print_help()
        sys.exit(1)

    # Find the path to the settings
    settings = opts.settings or \
        os.path.expanduser('~/.openslides/openslidessettings.py')

    # Create settings if necessary
    if not os.path.exists(settings):
        create_settings(settings)

    # Set the django environment to the settings
    setup_django_environment(settings)

    # Find url to openslides
    addr, port = detect_listen_opts(opts.address, opts.port)
    if port == 80:
        url = "http://%s" % addr
    else:
        url = "http://%s:%d" % (addr, port)

    # Create Database if necessary
    if not database_exists() or opts.syncdb:
        run_syncdb()
        set_system_url(url)
        create_or_reset_admin_user()

    # Reset Admin
    elif opts.reset_admin:
        create_or_reset_admin_user()

    # Start OpenSlides
    if opts.no_reload:
        extra_args = ['--noreload']
    else:
        extra_args = []
    start_openslides(addr, port, start_browser_url=url, extra_args=extra_args)


def create_settings(settings):
    path_to_dir = os.path.dirname(settings)

    setting_content = CONFIG_TEMPLATE % dict(
        default_key=base64.b64encode(os.urandom(KEY_LENGTH)),
        dbpath=os.path.join(path_to_dir, 'database.db'))

    if not os.path.exists(path_to_dir):
        os.makedirs(path_to_dir)

    with open(settings, 'w') as settings_file:
        settings_file.write(setting_content)


def setup_django_environment(settings):
    sys.path.append(os.path.dirname(settings))
    setting_module = os.path.basename(settings)[:-3]
    os.environ[django.conf.ENVIRONMENT_VARIABLE] = setting_module


def detect_listen_opts(address, port):
    if address is None:
        try:
            address = socket.gethostbyname(socket.gethostname())
        except socket.error:
            address = "127.0.0.1"

    if port is None:
        # test if we can use port 80
        s = socket.socket()
        port = 80
        try:
            s.bind((address, port))
            s.listen(-1)
        except socket.error:
            port = 8000
        finally:
            s.close()

    return address, port


def database_exists():
    """Detect if database exists"""
    # can't be imported in global scope as they already require
    # the settings module during import
    from django.db import DatabaseError
    from django.core.exceptions import ImproperlyConfigured
    from openslides.participant.models import User

    try:
        User.objects.count()
    except DatabaseError:
        return False
    except ImproperlyConfigured:
        print "Your settings file seems broken"
        sys.exit(0)
    else:
        return True


def run_syncdb():
    # now initialize the database
    argv = ["", "syncdb", "--noinput"]
    execute_from_command_line(argv)


def set_system_url(url):
    # can't be imported in global scope as it already requires
    # the settings module during import
    from openslides.config.models import config

    key = "participant_pdf_system_url"
    if key in config:
        return
    config[key] = url


def create_or_reset_admin_user():
    # can't be imported in global scope as it already requires
    # the settings module during import
    from openslides.participant.models import User
    try:
        admin = User.objects.get(username="admin")
        print("Password for user admin was reset to 'admin'")
    except User.DoesNotExist:
        admin = User()
        admin.username = 'admin'
        admin.last_name = 'Admin User'
        print("Created default admin user")

    admin.is_superuser = True
    admin.default_password = 'admin'
    admin.set_password(admin.default_password)
    admin.save()


def start_openslides(addr, port, start_browser_url=None, extra_args=[]):
    argv = ["", "runserver", '--noreload'] + extra_args

    argv.append("%s:%d" % (addr, port))

    if start_browser_url:
        start_browser(start_browser_url)
    execute_from_command_line(argv)


def start_browser(url):
    browser = webbrowser.get()

    def f():
        time.sleep(1)
        browser.open(url)

    t = threading.Thread(target=f)
    t.start()


if __name__ == "__main__":
    main()