import importlib.resources
import os
import socket

from flask import Flask
from flask_kerberos import init_kerberos
from zope import component

from .error_handlers import register_error_handlers
from ceo_common.interfaces import IConfig, IKerberosService, ILDAPService, IFileService, \
    IMailmanService, IMailService, IUWLDAPService, IHTTPClient
from ceo_common.model import Config, HTTPClient, RemoteMailmanService
from ceod.model import KerberosService, LDAPService, FileService, \
    MailmanService, MailService, UWLDAPService


def create_app(flask_config={}):
    app = Flask(__name__)
    app.config.from_mapping(flask_config)

    if app.config.get('ENV') == 'development' and 'CEOD_CONFIG' not in os.environ:
        with importlib.resources.path('ceo_common.test', 'ceod_dev.ini') as p:
            config_file = p.__fspath__()
    else:
        config_file = None
    cfg = Config(config_file)
    component.provideUtility(cfg, IConfig)

    init_kerberos(app, service='ceod')

    hostname = socket.gethostname()
    # Only ceod_admin_host has the ceod/admin key in its keytab
    if hostname == cfg.get('ceod_admin_host'):
        krb_srv = KerberosService(cfg.get('ldap_admin_principal'))

        from ceod.api import members
        app.register_blueprint(members.bp, url_prefix='/api/members')
    else:
        fqdn = socket.getfqdn()
        krb_srv = KerberosService(f'ceod/{fqdn}')
    component.provideUtility(krb_srv, IKerberosService)

    # Any host can use LDAPService, but only ceod_admin_host can write
    ldap_srv = LDAPService()
    component.provideUtility(ldap_srv, ILDAPService)

    http_client = HTTPClient()
    component.provideUtility(http_client, IHTTPClient)

    # Only instantiate FileService if this host has NFS no_root_squash
    # If admin_host and fs_root_host become separate, we will need
    # to create a RemoteFileService
    if hostname == cfg.get('ceod_fs_root_host'):
        file_srv = FileService()
        component.provideUtility(file_srv, IFileService)

    # Only offer mailman API if this host is running Mailman
    if hostname == cfg.get('ceod_mailman_host'):
        mailman_srv = MailmanService()
        component.provideUtility(mailman_srv, IMailmanService)

        from ceod.api import mailman
        app.register_blueprint(mailman.bp, url_prefix='/api/mailman')
    else:
        mailman_srv = RemoteMailmanService()
        component.provideUtility(mailman_srv, IMailmanService)

    mail_srv = MailService()
    component.provideUtility(mail_srv, IMailService)

    uwldap_srv = UWLDAPService()
    component.provideUtility(uwldap_srv, IUWLDAPService)

    from ceod.api import uwldap
    app.register_blueprint(uwldap.bp, url_prefix='/api/uwldap')

    register_error_handlers(app)

    @app.route('/ping')
    def ping():
        """Health check"""
        return 'pong\n'

    return app