const cleanUpQueryParams = require('../../middleware/clean-up-query-params');
const credentials = require('../../middleware/credentials');
const dbConnSetup = require('../../middleware/db-conn-setup');
const authorize = require('../../middleware/authorize');
const initProfiler = require('./middlewares/init-profiler');
const checkJsonContentType = require('./middlewares/check-json-content-type');
const incrementMapViewCount = require('./middlewares/increment-map-view-count');
const augmentLayergroupData = require('./middlewares/augment-layergroup-data');
const cacheControlHeader = require('../../middleware/cache-control-header');
const cacheChannelHeader = require('../../middleware/cache-channel-header');
const surrogateKeyHeader = require('../../middleware/surrogate-key-header');
const lastModifiedHeader = require('../../middleware/last-modified-header');
const lastUpdatedTimeLayergroup = require('./middlewares/last-updated-time-layergroup');
const layerStats = require('./middlewares/layer-stats');
const layergroupIdHeader = require('./middlewares/layergroup-id-header');
const layergroupMetadata = require('./middlewares/layergroup-metadata');
const mapError = require('./middlewares/map-error');
const NamedMapMapConfigProvider = require('../../models/mapconfig/provider/named-map-provider');
const CreateLayergroupMapConfigProvider = require('../../models/mapconfig/provider/create-layergroup-provider');
const rateLimit = require('../../middleware/rate-limit');
const { RATE_LIMIT_ENDPOINTS_GROUPS } = rateLimit;

/**
 * @param {AuthApi} authApi
 * @param {PgConnection} pgConnection
 * @param {TemplateMaps} templateMaps
 * @param {MapBackend} mapBackend
 * @param metadataBackend
 * @param {SurrogateKeysCache} surrogateKeysCache
 * @param {UserLimitsApi} userLimitsApi
 * @param {LayergroupAffectedTables} layergroupAffectedTables
 * @param {MapConfigAdapter} mapConfigAdapter
 * @param {StatsBackend} statsBackend
 * @constructor
 */
function NamedMapController (
    pgConnection,
    templateMaps,
    mapBackend,
    metadataBackend,
    surrogateKeysCache,
    userLimitsApi,
    layergroupAffectedTables,
    mapConfigAdapter,
    statsBackend,
    authApi,
    layergroupMetadata
) {
    this.pgConnection = pgConnection;
    this.templateMaps = templateMaps;
    this.mapBackend = mapBackend;
    this.metadataBackend = metadataBackend;
    this.surrogateKeysCache = surrogateKeysCache;
    this.userLimitsApi = userLimitsApi;
    this.layergroupAffectedTables = layergroupAffectedTables;
    this.mapConfigAdapter = mapConfigAdapter;
    this.statsBackend = statsBackend;
    this.authApi = authApi;
    this.layergroupMetadata = layergroupMetadata;
}

module.exports = NamedMapController;

NamedMapController.prototype.register = function (templateRouter) {
    templateRouter.get(
        `/:template_id/jsonp`,
        this.composeInstantiateTemplateMiddleware()
    );

    templateRouter.post(
        `/:template_id`,
        this.composeInstantiateTemplateMiddleware()
    );
};

NamedMapController.prototype.composeInstantiateTemplateMiddleware = function () {
    const isTemplateInstantiation = true;
    const useTemplateHash = true;
    const includeQuery = false;
    const label = 'NAMED MAP LAYERGROUP';
    const addContext = false;

    return [
        credentials(),
        authorize(this.authApi),
        dbConnSetup(this.pgConnection),
        rateLimit(this.userLimitsApi, RATE_LIMIT_ENDPOINTS_GROUPS.NAMED),
        cleanUpQueryParams(['aggregation']),
        initProfiler(isTemplateInstantiation),
        checkJsonContentType(),
        checkInstantiteLayergroup(),
        getTemplate(
            this.templateMaps,
            this.pgConnection,
            this.metadataBackend,
            this.userLimitsApi,
            this.mapConfigAdapter,
            this.layergroupAffectedTables
        ),
        instantiateLayergroup(
            this.mapBackend,
            this.userLimitsApi,
            this.pgConnection,
            this.layergroupAffectedTables
        ),
        incrementMapViewCount(this.metadataBackend),
        augmentLayergroupData(),
        cacheControlHeader({ ttl: global.environment.varnish.layergroupTtl || 86400, revalidate: true }),
        cacheChannelHeader(),
        surrogateKeyHeader({ surrogateKeysCache: this.surrogateKeysCache }),
        lastModifiedHeader({ now: true }),
        lastUpdatedTimeLayergroup(),
        layerStats(this.pgConnection, this.statsBackend),
        layergroupIdHeader(this.templateMaps ,useTemplateHash),
        layergroupMetadata(this.layergroupMetadata, includeQuery),
        mapError({ label, addContext })
    ];
};

function checkInstantiteLayergroup () {
    return function checkInstantiteLayergroupMiddleware(req, res, next) {
        if (req.method === 'GET') {
            const { callback, config } = req.query;

            if (callback === undefined || callback.length === 0) {
                return next(new Error('callback parameter should be present and be a function name'));
            }

            if (config) {
                try {
                    req.body = JSON.parse(config);
                } catch(e) {
                    return next(new Error('Invalid config parameter, should be a valid JSON'));
                }
            }
        }

        req.profiler.done('checkInstantiteLayergroup');

        return next();
    };
}

function getTemplate (
    templateMaps,
    pgConnection,
    metadataBackend,
    userLimitsApi,
    mapConfigAdapter,
    affectedTablesCache
) {
    return function getTemplateMiddleware (req, res, next) {
        const templateParams = req.body;
        const { user, dbuser, dbname, dbpassword, dbhost, dbport } = res.locals;
        const { template_id } = req.params;
        const { auth_token } = req.query;

        const params = Object.assign({ dbuser, dbname, dbpassword, dbhost, dbport }, req.query);

        const mapConfigProvider = new NamedMapMapConfigProvider(
            templateMaps,
            pgConnection,
            metadataBackend,
            userLimitsApi,
            mapConfigAdapter,
            affectedTablesCache,
            user,
            template_id,
            templateParams,
            auth_token,
            params
        );

        mapConfigProvider.getMapConfig((err, mapConfig, rendererParams) => {
            req.profiler.done('named.getMapConfig');
            if (err) {
                return next(err);
            }

            res.locals.mapConfig = mapConfig;
            res.locals.rendererParams = rendererParams;
            res.locals.mapConfigProvider = mapConfigProvider;

            next();
        });
    };
}

function instantiateLayergroup (mapBackend, userLimitsApi, pgConnection, affectedTablesCache) {
    return function instantiateLayergroupMiddleware (req, res, next) {
        const { user, mapConfig, rendererParams } = res.locals;
        const mapConfigProvider = new CreateLayergroupMapConfigProvider(
            mapConfig,
            user,
            userLimitsApi,
            pgConnection,
            affectedTablesCache,
            rendererParams
        );

        mapBackend.createLayergroup(mapConfig, rendererParams, mapConfigProvider, (err, layergroup) => {
            req.profiler.done('createLayergroup');
            if (err) {
                return next(err);
            }

            res.body = layergroup;

            const { mapConfigProvider } = res.locals;

            res.locals.analysesResults = mapConfigProvider.analysesResults;
            res.locals.template = mapConfigProvider.template;
            res.locals.context = mapConfigProvider.context;

            next();
        });
    };
}