"""
This module is responsible for the
entire provisioning lifecycle.
"""
import os
import logging
import time
import json
import datetime
from functools import reduce
from concurrent.futures import Future
from concurrent.futures import ProcessPoolExecutor, ThreadPoolExecutor
from brian_dashboard_manager.config import DEFAULT_ORGANIZATIONS, STATE_PATH
from brian_dashboard_manager.grafana.utils.request import AdminRequest, \
    TokenRequest

from brian_dashboard_manager.grafana.organization import \
    get_organizations, create_organization, create_api_token, \
    delete_api_token, delete_expired_api_tokens, set_home_dashboard
from brian_dashboard_manager.grafana.dashboard import find_dashboard, \
    get_dashboard_definitions, create_dashboard, delete_dashboard
from brian_dashboard_manager.grafana.datasource import \
    check_provisioned, create_datasource
from brian_dashboard_manager.grafana.folder import find_folder, \
    delete_folder, get_folders
from brian_dashboard_manager.inventory_provider.interfaces import \
    get_gws_direct, get_gws_indirect, get_interfaces

from brian_dashboard_manager.templating.helpers import \
    get_aggregate_dashboard_data, get_interface_data, \
    get_nren_interface_data, get_dashboard_data, \
    get_nren_dashboard_data, get_aggregate_interface_data

from brian_dashboard_manager.templating.gws import generate_gws, \
    generate_indirect

from brian_dashboard_manager.templating.render import render_dashboard

logger = logging.getLogger(__name__)


def provision_folder(token_request, folder_name, dash,
                     ds_name, excluded_dashboards):
    """
    Function to provision dashboards within a folder.
    """

    def _check_valid(interface):
        return interface['dashboard_info']['name'] != ''

    folder = find_folder(token_request, folder_name)
    tag = dash['tag']
    interfaces = list(filter(_check_valid, dash['interfaces']))

    # dashboard should include error panels
    errors = dash.get('errors', False)

    is_nren = folder_name == 'NREN Access'
    if is_nren:
        data = get_nren_interface_data(interfaces)
        dash_data = get_nren_dashboard_data(data, ds_name, tag)
    else:
        data = get_interface_data(interfaces)
        dash_data = get_dashboard_data(data, ds_name, tag, errors)

    if not isinstance(excluded_dashboards, list):
        excluded_dashboards = []
    else:
        excluded_dashboards = [s.lower() for s in excluded_dashboards]

    provisioned = []

    with ThreadPoolExecutor(max_workers=4) as executor:
        for dashboard in dash_data:
            rendered = render_dashboard(dashboard, nren=is_nren)
            if rendered.get('title').lower() in excluded_dashboards:
                executor.submit(delete_dashboard, token_request,
                                rendered, folder['id'])
                continue
            provisioned.append(executor.submit(create_dashboard, token_request,
                                               rendered, folder['id']))
    return [r.result() for r in provisioned]


def provision_aggregate(token_request, folder,
                        dash, ds_name):

    name = dash['dashboard_name']
    tag = dash['tag']
    interfaces = dash['interfaces']
    data = get_aggregate_interface_data(interfaces, name)

    dashboard = get_aggregate_dashboard_data(
        f'Aggregate - {name}', data, ds_name, tag)

    rendered = render_dashboard(dashboard)
    return create_dashboard(token_request, rendered, folder['id'])


def provision_maybe(config):
    with open(STATE_PATH, 'r+') as f:
        def write_timestamp(timestamp, provisioning):
            f.seek(0)
            f.write(json.dumps(
                {'timestamp': timestamp, 'provisioning': provisioning}))
            f.truncate()

        try:
            # don't conditionally provision in dev
            val = os.environ.get('FLASK_ENV') != 'development'
            now = datetime.datetime.now()
            write_timestamp(now.timestamp(), val)
            provision(config)
        except Exception as e:
            logger.exception('Uncaught Exception:')
            raise e
        finally:
            now = datetime.datetime.now()
            write_timestamp(now.timestamp(), False)


def provision(config):

    request = AdminRequest(**config)
    all_orgs = get_organizations(request)

    orgs_to_provision = config.get('organizations', DEFAULT_ORGANIZATIONS)
    ignored_folders = config.get('ignored_folders', [])

    missing = (org['name'] for org in orgs_to_provision
               if org['name'] not in [org['name'] for org in all_orgs])

    for org_name in missing:
        org_data = create_organization(request, org_name)
        all_orgs.append(org_data)

    interfaces = get_interfaces(config['inventory_provider'])
    tokens = []

    start = time.time()

    for org in all_orgs:
        org_id = org['id']
        delete_expired_api_tokens(request, org_id)
        token = create_api_token(request, org_id)
        token_request = TokenRequest(token=token['key'], **config)
        tokens.append((org_id, token['id']))

        logger.info(
            f'--- Provisioning org {org["name"]} (ID #{org_id}) ---')

        try:
            org_config = next(
                o for o in orgs_to_provision if o['name'] == org['name'])
        except StopIteration:
            org_config = None

        if not org_config:
            logger.error(
                f'Org {org["name"]} does not have valid configuration.')
            org['info'] = 'Org exists in grafana but is not configured'
            continue

        # Only provision influxdb datasource for now
        datasource = config.get('datasources').get('influxdb')

        # Provision missing data sources
        if not check_provisioned(token_request, datasource):
            ds = create_datasource(token_request,
                                   datasource,
                                   config.get('datasources'))
            if ds:
                logger.info(
                    f'Provisioned datasource: {datasource["name"]}')

        excluded_nrens = org_config['excluded_nrens']

        def excluded(interface):
            desc = interface['description'].lower()
            lab = 'lab.office' in interface['router'].lower()
            to_exclude = any(nren.lower() in desc for nren in excluded_nrens)
            return not (to_exclude or lab)

        relevant_interfaces = list(filter(excluded, interfaces))

        dashboards = {
            'NREN': {
                'tag': ['customers'],
                'folder_name': 'NREN Access',
                'interfaces': []
            },
            'CLS': {
                'tag': 'CLS',
                'folder_name': 'CLS',
                'interfaces': []
            },
            'RE_PEER': {
                'tag': 'RE_PEER',
                'folder_name': 'RE Peer',
                'interfaces': []
            },
            'RE_CUST': {
                'tag': 'RE_CUST',
                'folder_name': 'RE Customer',
                'interfaces': []
            },
            'GEANTOPEN': {
                'tag': 'GEANTOPEN',
                'folder_name': 'GEANTOPEN',
                'interfaces': []
            },
            'GCS': {
                'tag': 'AUTOMATED_L2_CIRCUITS',
                'folder_name': 'GCS',
                'interfaces': []
            },
            'L2_CIRCUIT': {
                'tag': 'L2_CIRCUITS',
                'folder_name': 'L2 Circuit',
                'interfaces': []
            },
            'LHCONE_PEER': {
                'tag': 'LHCONE_PEER',
                'folder_name': 'LHCONE Peer',
                'interfaces': []
            },
            'LHCONE_CUST': {
                'tag': 'LHCONE_CUST',
                'folder_name': 'LHCONE Customer',
                'interfaces': []
            },
            'MDVPN_CUSTOMERS': {
                'tag': 'MDVPN',
                'folder_name': 'MDVPN Customers',
                'interfaces': []
            },
            'INFRASTRUCTURE_BACKBONE': {
                'tag': 'BACKBONE',
                'errors': True,
                'folder_name': 'Infrastructure Backbone',
                'interfaces': []
            },
            'IAS_PRIVATE': {
                'tag': 'IAS_PRIVATE',
                'folder_name': 'IAS Private',
                'interfaces': []
            },
            'IAS_PUBLIC': {
                'tag': 'IAS_PUBLIC',
                'folder_name': 'IAS Public',
                'interfaces': []
            },
            'IAS_CUSTOMER': {
                'tag': 'IAS_CUSTOMER',
                'folder_name': 'IAS Customer',
                'interfaces': []
            },
            'IAS_UPSTREAM': {
                'tag': ['IAS_UPSTREAM', 'UPSTREAM'],
                'folder_name': 'IAS Upstream',
                'interfaces': []
            },
            'GWS_PHY_UPSTREAM': {
                'tag': ['GWS_UPSTREAM', 'UPSTREAM'],
                'errors': True,
                'folder_name': 'GWS PHY Upstream',
                'interfaces': []
            }
        }

        agg_dashboards = {
            'CLS_PEERS': {
                'tag': 'cls_peers',
                'dashboard_name': 'CLS Peers',
                'interfaces': []
            },
            'IAS_PEERS': {
                'tag': 'ias_peers',
                'dashboard_name': 'IAS Peers',
                'interfaces': []
            },
            'IAS_UPSTREAM': {
                'tag': 'gws_upstreams',
                'dashboard_name': 'GWS Upstreams',
                'interfaces': []
            },
            'LHCONE': {
                'tag': 'lhcone',
                'dashboard_name': 'LHCONE',
                'interfaces': []
            },
            'CAE1': {
                'tag': 'cae',
                'dashboard_name': 'CAE1',
                'interfaces': []
            }
        }
        # Provision dashboards, overwriting existing ones.
        ds_name = datasource.get('name', 'PollerInfluxDB')
        excluded_folders = org_config.get('excluded_folders', {})

        def get_uid(prev, curr):
            prev[curr.get('uid')] = False
            return prev

        # Map of dashboard UID -> whether it has been updated.
        # This is used to remove stale dashboards at the end.
        updated = find_dashboard(token_request) or []
        updated = reduce(get_uid, updated, {})

        # General is a base folder present in Grafana
        folders_to_keep = ['General', 'GWS Indirect',
                           'GWS Direct', 'Aggregates']
        folders_to_keep.extend([dash['folder_name']
                                for dash in dashboards.values()])

        def update_dash_list(dashboards):
            for dashboard in dashboards:
                if isinstance(dashboard, Future):
                    dashboard = dashboard.result()
                if dashboard is None:
                    continue
                updated[dashboard.get('uid')] = True

        # loop over interfaces and add them to the dashboard_name
        # -> folder mapping structure `dashboards` above, for convenience.
        for iface in relevant_interfaces:
            for dash_name in iface['dashboards']:

                # add interface to matched dashboard
                if dash_name in dashboards:
                    ifaces = dashboards[dash_name]['interfaces']
                    ifaces.append(iface)

                # add to matched aggregate dashboard
                if dash_name in agg_dashboards:
                    ifaces = agg_dashboards[dash_name]['interfaces']
                    ifaces.append(iface)

        # provision dashboards and their folders
        with ProcessPoolExecutor(max_workers=4) as executor:
            provisioned = []
            for folder in dashboards.values():
                folder_name = folder['folder_name']
                exclude = excluded_folders.get(folder_name)

                # boolean True means entire folder excluded
                # if list, it is specific dashboard names not to provision
                # so is handled at provision time.
                if exclude:
                    if isinstance(exclude, bool):
                        executor.submit(
                            delete_folder, token_request, folder_name)
                        continue

                logger.info(
                    f'Provisioning {org["name"]}/{folder_name} dashboards')
                res = executor.submit(provision_folder, token_request,
                                      folder_name, folder, ds_name,
                                      exclude)
                provisioned.append(res)

            for result in provisioned:
                folder = result.result()
                if folder is None:
                    continue
                update_dash_list(folder)

        # fetch GWS direct data and provision related dashboards
        logger.info('Provisioning GWS Indirect dashboards')
        folder_name = 'GWS Indirect'
        exclude_indirect = excluded_folders.get(folder_name, False)
        if isinstance(exclude_indirect, bool) and exclude_indirect:
            # don't provision GWS Direct folder
            delete_folder(token_request, folder_name)
        else:
            folder = find_folder(token_request, folder_name)
            with ThreadPoolExecutor(max_workers=4) as executor:
                gws_indirect_data = get_gws_indirect(
                    config['inventory_provider'])
                provisioned = []
                dashes = generate_indirect(gws_indirect_data, ds_name)
                for dashboard in dashes:
                    rendered = render_dashboard(dashboard)
                    provisioned.append(executor.submit(create_dashboard,
                                                       token_request,
                                                       rendered, folder['id']))

                update_dash_list(provisioned)

        # fetch GWS direct data and provision related dashboards
        logger.info('Provisioning GWS Direct dashboards')
        folder_name = 'GWS Direct'
        exclude_gws = excluded_folders.get(folder_name, False)
        if isinstance(exclude_gws, bool) and exclude_gws:
            # don't provision GWS Direct folder
            delete_folder(token_request, folder_name)
        else:
            folder = find_folder(token_request, folder_name)
            with ThreadPoolExecutor(max_workers=4) as executor:
                gws_data = get_gws_direct(config['inventory_provider'])
                provisioned = []

                for dashboard in generate_gws(gws_data, ds_name):
                    rendered = render_dashboard(dashboard)
                    provisioned.append(executor.submit(create_dashboard,
                                                       token_request,
                                                       rendered, folder['id']))

                update_dash_list(provisioned)

        exclude_agg = excluded_folders.get('Aggregates', [])

        if isinstance(exclude_agg, bool) and exclude_agg:
            # don't provision aggregate folder
            delete_folder(token_request, 'Aggregates')
        else:
            with ProcessPoolExecutor(max_workers=4) as executor:
                provisioned = []
                agg_folder = find_folder(token_request, 'Aggregates')
                for dash in agg_dashboards.values():
                    if dash['dashboard_name'] in exclude_agg:
                        dash_name = {
                            'title': f'Aggregate - {dash["dashboard_name"]}'}
                        executor.submit(delete_dashboard,
                                        token_request, dash_name,
                                        agg_folder['id'])
                        continue
                    logger.info(f'Provisioning {org["name"]}' +
                                f'/Aggregate {dash["dashboard_name"]} dashboards')  # noqa: E501
                    res = executor.submit(
                        provision_aggregate, token_request,
                        agg_folder, dash, ds_name)
                    provisioned.append(res)

                update_dash_list(provisioned)

        # Statically defined dashboards from json files
        excluded_dashboards = org_config.get('excluded_dashboards', [])
        logger.info('Provisioning static dashboards')
        for dashboard in get_dashboard_definitions():
            if dashboard['title'] not in excluded_dashboards:
                res = create_dashboard(token_request, dashboard)
                if res:
                    updated[res.get('uid')] = True
            else:
                delete_dashboard(token_request, dashboard)

        # Home dashboard is always called "Home"
        # Make sure it's set for the organization
        logger.info('Configuring Home dashboard')
        is_staff = org['name'] == 'GÉANT Staff'
        set_home_dashboard(token_request, is_staff)
        # just hardcode that we updated home dashboard
        updated['home'] = True

        # get dashboard UIDs from ignored folders
        # and make sure we don't touch them
        for name in ignored_folders:
            folders_to_keep.append(name)
            logger.info(
                f'Ignoring dashboards under the folder {org["name"]}/{name}')
            folder = find_folder(token_request, name, create=False)
            if folder is None:
                continue
            to_ignore = find_dashboard(token_request, folder_id=folder['id'])

            if to_ignore is None:
                continue

            for dash in to_ignore:
                # mark it updated, so we don't modify it.
                updated[dash['uid']] = True

        for dash, provisioned in updated.items():
            if not provisioned:
                logger.info(f'Deleting stale dashboard with UID {dash}')
                delete_dashboard(token_request, {'uid': dash})

        all_folders = get_folders(token_request)
        folders_to_keep = set(folders_to_keep)

        for folder in all_folders:
            if folder['title'] not in folders_to_keep:
                delete_folder(token_request, uid=folder['uid'])

    logger.info(f'Time to complete: {time.time() - start}')
    for org_id, token in tokens:
        delete_api_token(request, org_id, token)

    return all_orgs