/* jshint esversion: 6 */
/* globals process */

const Crypto = require('crypto');
const WriteQueue = require("./write-queue");
const BatchRead = require("./batch-read");

const Keys = require("./keys");
const Core = require("./commands/core");

const Quota = require("./commands/quota");
const Util = require("./common-util");

module.exports.create = function (config) {

    const Env = {
        OFFLINE_MODE: false,
        FRESH_KEY: '',
        FRESH_MODE: true,
        DEV_MODE: false,
        configCache: {},
        flushCache: function () {
            Env.configCache = {};
            Env.FRESH_KEY = +new Date();
            if (!(Env.DEV_MODE || Env.FRESH_MODE)) { Env.FRESH_MODE = true; }
            if (!Env.Log) { return; }
            Env.Log.info("UPDATING_FRESH_KEY", Env.FRESH_KEY);
        },

        Log: undefined,
        // store
        id: Crypto.randomBytes(8).toString('hex'),

        launchTime: +new Date(),

        inactiveTime: config.inactiveTime,
        archiveRetentionTime: config.archiveRetentionTime,
        accountRetentionTime: config.accountRetentionTime,

    // TODO implement mutability
        adminEmail: config.adminEmail,
        supportMailbox: config.supportMailboxPublicKey,

        metadata_cache: {},
        channel_cache: {},
        cache_checks: {},

        queueStorage: WriteQueue(),
        queueDeletes: WriteQueue(),
        queueValidation: WriteQueue(),
        queueMetadata: WriteQueue(),

        batchIndexReads: BatchRead("HK_GET_INDEX"),
        batchMetadata: BatchRead('GET_METADATA'),
        batchRegisteredUsers: BatchRead("GET_REGISTERED_USERS"),
        batchDiskUsage: BatchRead('GET_DISK_USAGE'),
        batchUserPins: BatchRead('LOAD_USER_PINS'),
        batchTotalSize: BatchRead('GET_TOTAL_SIZE'),
        batchAccountQuery: BatchRead("QUERY_ACCOUNT_SERVER"),

        intervals: {},
        maxUploadSize: config.maxUploadSize || (20 * 1024 * 1024),
        premiumUploadSize: false, // overridden below...
        Sessions: {},
        paths: {},
        //msgStore: config.store,

        netfluxUsers: {},

        pinStore: undefined,

        limits: {},
        admins: [],
        WARN: function (e, output) { // TODO deprecate this
            if (!Env.Log) { return; }
            if (e && output) {
                Env.Log.warn(e, {
                    output: output,
                    message: String(e),
                    stack: new Error(e).stack,
                });
            }
        },

        allowSubscriptions: config.allowSubscriptions === true,
        blockDailyCheck: config.blockDailyCheck === true,

        myDomain: config.myDomain,
        mySubdomain: config.mySubdomain, // only exists for the accounts integration
        customLimits: {},
        // FIXME this attribute isn't in the default conf
        // but it is referenced in Quota
        domain: config.domain,

        maxWorkers: config.maxWorkers,
        disableIntegratedTasks: config.disableIntegratedTasks || false,
        disableIntegratedEviction: config.disableIntegratedEviction || false,
        lastEviction: +new Date(),
        evictionReport: {},
        commandTimers: {},
    };

    (function () {
    // mode can be FRESH (default), DEV, or PACKAGE
        if (process.env.PACKAGE) {
        // `PACKAGE=1 node server` uses the version string from package.json as the cache string
            //console.log("PACKAGE MODE ENABLED");
            Env.FRESH_MODE = false;
            Env.DEV_MODE = false;
        } else if (process.env.DEV) {
        // `DEV=1 node server` will use a random cache string on every page reload
            //console.log("DEV MODE ENABLED");
            Env.FRESH_MODE = false;
            Env.DEV_MODE = true;
        } else {
        // `FRESH=1 node server` will set a random cache string when the server is launched
        // and use it for the process lifetime or until it is reset from the admin panel
            //console.log("FRESH MODE ENABLED");
            Env.FRESH_KEY = +new Date();
        }

        // Offline mode is mostly for development. It lets us test clientside cache and offline support
        if (process.env.OFFLINE) { Env.OFFLINE_MODE = true; }
    }());

    Env.checkCache = function (channel) {
        var f = Env.cache_checks[channel] || Util.throttle(function () {
            delete Env.cache_checks[channel];
            if (Env.channel_cache[channel]) { return; }
            delete Env.metadata_cache[channel];
        }, 30000);
        f();
    };

    (function () {
        var custom = config.customLimits;
        if (!custom) { return; }

        var stored = Env.customLimits;

        Object.keys(custom).forEach(function (k) {
            var unsafeKey = Keys.canonicalize(k);

            if (!unsafeKey) {
                console.log("INVALID_CUSTOM_LIMIT_ID", {
                    message: "A custom quota upgrade was provided via your config with an invalid identifier. It will be ignored.",
                    key: k,
                    value: custom[k],
                });
                return;
            }

            if (stored[unsafeKey]) {
                console.log("INVALID_CUSTOM_LIMIT_DUPLICATED", {
                    message: "A duplicated custom quota upgrade was provided via your config which would have overridden an existing value. It will be ignored.",
                    key: k,
                    value: custom[k],
                });
                return;
            }

            if (!Quota.isValidLimit(custom[k])) {
                console.log("INVALID_CUSTOM_LIMIT_VALUE", {
                    message: "A custom quota upgrade was provided via your config with an invalid value. It will be ignored.",
                    key: k,
                    value: custom[k],
                });
                return;
            }

            var limit = stored[unsafeKey] = Util.clone(custom[k]);
            limit.origin = 'config';
        });
    }());

    (function () {
        var pes = config.premiumUploadSize;
        if (!isNaN(pes) && pes >= Env.maxUploadSize) {
            Env.premiumUploadSize = pes;
        }
    }());

    var paths = Env.paths;

    var keyOrDefaultString = function (key, def) {
        return typeof(config[key]) === 'string'? config[key]: def;
    };

    paths.pin = keyOrDefaultString('pinPath', './pins');
    paths.block = keyOrDefaultString('blockPath', './block');
    paths.data = keyOrDefaultString('filePath', './datastore');
    paths.staging = keyOrDefaultString('blobStagingPath', './blobstage');
    paths.blob = keyOrDefaultString('blobPath', './blob');
    paths.decree = keyOrDefaultString('decreePath', './data/');
    paths.archive = keyOrDefaultString('archivePath', './data/archive');
    paths.task = keyOrDefaultString('taskPath', './tasks');

    Env.defaultStorageLimit = typeof(config.defaultStorageLimit) === 'number' && config.defaultStorageLimit >= 0?
        config.defaultStorageLimit:
        Core.DEFAULT_LIMIT;

    try {
        Env.admins = (config.adminKeys || []).map(function (k) {
            try {
                return Keys.canonicalize(k);
            } catch (err) {
                return;
            }
        }).filter(Boolean);
    } catch (e) {
        console.error("Can't parse admin keys. Please update or fix your config.js file!");
    }

    return Env;
};