const { lib } = require('crypto-js');

class WTVClientSessionData {

    fs = require('fs');
    path = require('path');

    ssid = null;
    data_store = null;
    session_store = null;
    login_security = null;
    capabilities = null;
    session_storage = "";
    minisrv_config = [];
    wtvshared = null;
    wtvmime = null;

    constructor(minisrv_config, ssid) {
        if (!minisrv_config) throw ("minisrv_config required");
        var WTVShared = require('./WTVShared.js')['WTVShared'];
        var WTVMime = require('./WTVMime.js');
        this.minisrv_config = minisrv_config;
        this.wtvshared = new WTVShared(minisrv_config);
        this.wtvmime = new WTVMime(minisrv_config);

        this.ssid = ssid;
        this.data_store = new Array();
        this.session_store = {};
    }

    /**
     * Returns the absolute path to the user's file store, or false if unregistered
     * @returns {string|boolean} Absolute path to the user's file store, or false if unregistered
     */
    getUserStoreDirectory() {
        if (!this.isRegistered()) return false;
        return this.minisrv_config.config.SessionStore + this.path.sep + this.ssid + this.path.sep;
    }

    /**
     * Store a file in the user's file store
     * @param {string} path Relative path to User's file store
     * @param {Buffer} data File data
     * @param {number|null} last_modified Unix timestamp to set last modified date to
     * @param {boolean} overwrite Overwrite if file exists
     * @returns {boolean} Whether or not the file was written
     */
    storeUserStoreFile(path, data, last_modified = null, overwrite = true) {
        var store_dir = this.getUserStoreDirectory();
        if (!store_dir) return false; // unregistered
        var result = false;        
        var path_split = path.split('/');
        var file_name = path_split.pop();
        var store_dir_path = this.wtvshared.makeSafePath(store_dir, path_split.join('/').replace('/', this.path.sep));
        var store_full_path = this.wtvshared.makeSafePath(store_dir_path, file_name);

        try {
            if (!this.fs.existsSync(store_dir_path)) this.fs.mkdirSync(store_dir_path, { recursive: true });
            var file_exists = this.fs.existsSync(store_full_path);
            if (!file_exists || (file_exists && overwrite)) result = this.fs.writeFileSync(store_full_path, data);
            if (result !== false && last_modified) {
                var file_timestamp = new Date(last_modified * 1000);
                fs.utimesSync(store_full_path, Date.now(), file_timestamp)
            }
        } catch (e) {
            console.error(" # User File Store failed", e);
        }
        return (result === false) ? false : true;
    }

    /**
     * Retrieves a file from the user store
     * @param {string} path Path relative to the User File Store
     * @returns {Buffer|false} Buffer data, or false if could not open file
     */
    getUserStoreFile(path) {
        var store_dir = this.getUserStoreDirectory();
        if (!store_dir) return false; // unregistered
        var store_dir_path = this.wtvshared.makeSafePath(store_dir, path.replace('/', this.path.sep));
        if (this.fs.existsSync(store_dir_path)) return this.fs.readFileSync(store_dir_path);
        else return false;
    }

    /**
     * Retrieves a file from the user store with a file://Disk/ url
     * @param {string} url file://Disk/ base url
     * @returns {Buffer|false} Buffer data, or false if could not open file
     */
    getUserStoreFileByURL(url) {
        var path_split = url.split('/');
        path_split.shift();
        path_split.shift();
        var store_dir_path = path_split.join('/').replace('/', this.path.sep);
        return this.getUserStoreFile(store_dir_path);
    }

    /**
    * Retrieves the Content-Type of a User Store File
    * @param {string} path Path relative to the User File Store
    * @returns {string|false} Content-Type, or false if could not open file
    */
    getUserStoreContentType(path) {
        return this.wtvmime.getSimpleContentType(path);
    }

    /**
     * Returns the number of user cookies
     * @returns {number} Number of cookies
     */
    countCookies() {
        return Object.keys(this.session_store.cookies).length || 0;
    }

    resetCookies() {
        this.session_store.cookies = {};
        // webtv likes to have at least one cookie in the list, set a dummy cookie for zefie's site expiring in 1 year.
        this.addCookie("wtv.zefie.com", "/", this.wtvshared.getUTCTime(365 * 86400000), "cookie_type=chocolatechip");
    }

    addCookie(domain, path = null, expires = null, data = null) {
        if (!this.checkCookies()) this.resetCookies();
        if (!domain) return false;
        else if (typeof (domain) == 'object') {
            // accept array as first argument
            if (domain.domain && domain.path && domain.expires && domain.data) var cookie_data = domain;
            else return false;
        } else {
            if (path && expires && data) {
                var cookie_data = new Array();
                cookie_data['cookie'] = unescape(data);
                cookie_data['expires'] = unescape(expires);
                cookie_data['path'] = unescape(path);
                cookie_data['domain'] = unescape(domain);
            } else {
                return false;
            }
        }

        var self = this;
        var cookie_index = -1;
        // see if we have a cookie for this domain/path
        Object.keys(this.session_store.cookies).forEach(function (k) {
            if (cookie_index >= 0) return;
            if (domain == self.session_store.cookies[k].domain && path == self.session_store.cookies[k].path) cookie_index = k;
        });
        // otherwise add a new one
        if (cookie_index == -1) cookie_index = this.countCookies();

        this.session_store.cookies[cookie_index] = Object.assign({}, cookie_data);

        return true;
    }

    getCookie(domain, path) {
        if (!this.checkCookies()) this.resetCookies();
        var self = this;
        var result = false;
        Object.keys(this.session_store['cookies']).forEach(function (k) {
            if (result != false) return;
            if (self.session_store['cookies'][k].domain == domain &&
                self.session_store['cookies'][k].path == path) {

                var current_epoch_utc = Date.parse((new Date()).toUTCString());
                var cookie_expires_epoch_utc = Date.parse(new Date(Date.parse(self.session_store['cookies'][k].expires)).toUTCString());
                if (cookie_expires_epoch_utc <= current_epoch_utc) self.deleteCookie(self.session_store['cookies'][k]);
                else result = self.session_store['cookies'][k];
            }
        });
        return result;
    }

    getCookieString(domain, path) {
        var cookie_data = this.getCookie(domain, path);
        /*
         var outstring = "";
        Object.keys(cookie_data).forEach(function (k) {
            outstring += k + "=" + escape(cookie_data[k]) + "&";
        });
        return outstring.substring(0, outstring.length - 1);
        */
        return cookie_data.cookie;
    }

    deleteCookie(domain, path = null) {
        var result = false;
        if (!this.checkCookies()) {
            this.resetCookies();
            return true;
        }
        if (!domain) return false;
        else if (typeof (domain) == 'object') {
            // accept array as first argument
            if (domain.domain && domain.path) {
                path = domain.path;
                domain = domain.domain;
            }
        } else if (!path) {
            return false;
        }

        var self = this;
        Object.keys(this.session_store['cookies']).forEach(function (k) {
            if (self.session_store['cookies'][k].domain == domain && self.session_store['cookies'][k].path == path) {
                delete self.session_store['cookies'][k];
                self.storeSessionData();
                result = true;
            }
        });

        return result;
    }

    checkCookies() {
        if (!this.session_store.cookies) return false;
        else if (this.session_store.cookies == []) return false;
        return true;
    }

    listCookies() {
        if (!this.checkCookies()) this.resetCookies();
        var outstring = "";
        var self = this;
        Object.keys(this.session_store.cookies).forEach(function (k) {
            outstring += self.session_store.cookies[k].domain + "\0" + self.session_store.cookies[k].path + "\0";
        });
        return outstring;
    }

    loadSessionData(raw_data = false) {
        try {
            if (this.fs.lstatSync(this.minisrv_config.config.SessionStore + this.path.sep + this.ssid + ".json")) {
                var json_data = this.fs.readFileSync(this.minisrv_config.config.SessionStore + this.path.sep + this.ssid + ".json", 'Utf8')
                if (raw_data) return json_data;

                var session_data = JSON.parse(json_data);
                this.session_store = session_data;
                return true;
            }
        } catch (e) {
            // Don't log error 'file not found', it just means the client isn't registered yet
            if (e.code != "ENOENT") console.error(" # Error loading session data for", this.wtvshared.filterSSID(this.ssid), e);
            return false;
        }
    }

    saveSessionData(force_write = false) {
        if (this.isRegistered()) {
            // load data from disk and merge new data
            var temp_store = this.session_store;
            if (this.loadSessionData()) this.session_store = Object.assign(this.session_store, temp_store);
            else this.session_store = temp_store;
            temp_store = null;
        } else {
            // do not write file if user is not registered, return true because this is not an error
            // force write needed to set the initial reg
            if (!force_write) return true;
        }
        
        try {
            // only save if file has changed
            var json_save_data = JSON.stringify(this.session_store);
            var json_load_data = this.loadSessionData(true);
            if (json_save_data != json_load_data) this.fs.writeFileSync(this.minisrv_config.config.SessionStore + this.path.sep + this.ssid + ".json", JSON.stringify(this.session_store), "Utf8");
            return true;
        } catch (e) {            
            console.error(" # Error saving session data for", this.wtvshared.filterSSID(this.ssid), e);
            return false;
        }
    }

    retrieveSessionData() {
        // alias
        return this.loadSessionData();
    }

    storeSessionData(force_write = false) {
        // alias
        return this.saveSessionData(force_write);
    }

    SaveIfRegistered() {
        if (this.isRegistered()) return this.saveSessionData();
        return false;
    }

    isRegistered() {
        var self = this;
        var ssid_match = false;
        this.fs.readdirSync(this.minisrv_config.config.SessionStore).forEach(file => {
            if (!file.match(/.*\.json/ig)) return;
            if (ssid_match) return;
            if (file.split('.')[0] == self.ssid) ssid_match = true;
        });
        return ssid_match;
    }

    unregisterBox() {
        try {
            if (this.fs.lstatSync(this.minisrv_config.config.SessionStore + this.path.sep + this.ssid + ".json")) {
                this.fs.unlinkSync(this.minisrv_config.config.SessionStore + this.path.sep + this.ssid + ".json");
                this.session_store = {};
                return true;
            }
        } catch (e) {
            // Don't log error 'file not found', it just means the client isn't registered yet
            console.error(" # Error deleting session data for", this.wtvshared.filterSSID(this.ssid), e);
            return false;
        }
    }

    hasCap(cap) {
        if (this.capabilities) {
            return this.capabilities[cap] || false;
        }
        return false;
    }

    getMaxUsernameLength() {
        if (parseInt(this.data_store['wtv-system-version'] < 4000)) {
            // older builds may crash with nicknames longer than 16 chars.
            // actual build where support started is yet unknown
            return 16;
        } else {
            // newer builds supported up to 32 chars, I think
            return 32;
        }
    }

    setIRCNick(nick) {
        // strip out unsupported chars
        nick = nick.replace(/[^a-zA-Z0-9\-\_\`\^]/g, "");

        // limit nick length based on build support
        nick = nick.substring(0, this.getMaxUsernameLength());

        // returns headers to send to client, while storing the new data in our session data.
        this.data_store['wtv-user-name'] = nick;
        this.data_store['wtv-irc-nick'] = nick;
        this.session_store.subscriber_irc_nick = nick;
        return "wtv-irc-nick: " + nick + "\nwtv-user-nick: " + nick;
    }

    isMiniBrowser() {
        if (this.data_store['wtv-need-upgrade'] || this.data_store['wtv-used-8675309']) return true;
        return false;
    }

    currentConnections() {
        if (this.data_store) {
            if (this.data_store.sockets) {
                return this.data_store.sockets.size;
            }
        }
        return 0;
    }

    getSessionData(key = null) {
        if (typeof (this.data_store) === 'session_store') return null;
        else if (key === null) return this.data_store;
        else if (this.session_store[key]) return this.session_store[key];
        else return null;
    }

    setSessionData(key, value) {
        if (key === null) throw ("ClientSessionData.set(): invalid key provided");
        if (typeof (this.session_store) === 'undefined') this.session_store = new Array();
        this.session_store[key] = value;
    }

    deleteSessionData(key) {
        if (key === null) throw ("ClientSessionData.delete(): invalid key provided");
        delete this.session_store[key];
    }


    get(key = null) {
        if (typeof (this.data_store) === 'undefined') return null;
        else if (key === null) return this.data_store;
        else if (this.data_store[key]) return this.data_store[key];
        else return null;
    }

    set(key, value) {
        if (key === null) throw ("ClientSessionData.set(): invalid key provided");
        if (typeof (this.data_store) === 'undefined') this.data_store = new Array();
        this.data_store[key] = value;
    }

    delete(key) {
        if (key === null) throw ("ClientSessionData.delete(): invalid key provided");
        delete this.data_store[key];
    }
}


module.exports = WTVClientSessionData;