"use strict";

class trserver extends EventTarget {
    #logcb;
    #log(loglevel, msg) {
        if (this.#logcb !== null) {
            this.#logcb(`server:${this.name}`, loglevel, msg);
        }
    }

    #name;
    get name() {
        return this.#name;
    }
    #rpcurl;
    #authHeader;
    #sessionHeader;
    #requests = [];

    #elements = {
        serverlist: {
            row: document.createElement('div'),
            name: document.createElement('div'),
            buttons: {}
        }
    };
    get element() {
        return this.#elements.serverlist.row;
    }
    addServerListButton(name, button) {
        if (this.#elements.serverlist.buttons[name] != null) {
            this.removeServerListButton(name);
        }
        this.#elements.serverlist.buttons[name] = button;
        this.#elements.serverlist.row.appendChild(button);
    }
    removeServerListButton(name) {
        if (this.#elements.serverlist.buttons[name] != null) {
            this.#elements.serverlist.row.removeChild(this.#elements.serverlist.buttons[name]);
            this.#elements.serverlist.buttons[name] = null;
        }
    }

    #torrentControls = {};
    addControl(hash, control) {
        this.#torrentControls[hash] = control;
    }
    getControl(hash) {
        return this.#torrentControls[hash];
    }

    #isOnline = false;
    #setOnline(online) {
        if (this.isOnline == online) {
            return;
        }
        this.#isOnline = online;
        let detail = {
        };
        let etype;
        if (online) {
            etype = 'torrentserver-online';
        }
        else {
            etype = 'torrentserver-offline';
        }
        this.dispatchEvent(new CustomEvent(etype, detail));
    }

    constructor (name, initdata, logcb = null) {
        super();
        this.#logcb = logcb;
        this.#name = name;
        this.#rpcurl = initdata.rpcurl;
        this.#authHeader = initdata.auth;
        this.#sessionHeader = null;

        this.#elements.serverlist.row.classList.add('d-flex', 'flex-row');
        this.#elements.serverlist.row.appendChild(this.#elements.serverlist.name);

        this.#elements.serverlist.name.classList.add('flex-grow-1');
        this.#elements.serverlist.name.appendChild(document.createTextNode(this.name));
    }

    #rpccall_prepare(method, args) {
        let request = {
            'payload': {
                'method': method,
                'arguments': args
            }
        };
        let tag = this.#requests.push(request) - 1;
        return tag;
    }

    #rpccall(tag) {
        let request = this.#requests[tag];
        //this.#logger(`[${tag}] >> ${request.payload.method}`);
        let rpc = new window.XMLHttpRequest();
        rpc.tag = tag;
        rpc.open('POST', this.#rpcurl);
        if (this.#authHeader != null) {
            rpc.setRequestHeader('authorization', this.#authHeader);
        }
        if (this.#sessionHeader != null) {
            rpc.setRequestHeader('X-Transmission-Session-Id', this.#sessionHeader);
        }
        rpc.setRequestHeader('content-type', 'application/json');
        rpc.addEventListener('readystatechange', this);
        rpc.addEventListener('timeout', this);
        rpc.addEventListener('error', this);
        rpc.timeout = 10000;
        try {
            rpc.send(JSON.stringify(request.payload));
        } catch (error) {
            this.#log(2, error);
        }
    }

    rpccall_debug(method, args) {
        var tag = this.#rpccall_prepare(method, args);
        let request = this.#requests[tag];
        request.success = console.info;
        this.#rpccall(tag);
    }

    handleEvent(e) {
        switch (e.type) {
            case 'readystatechange':
                if (e.target.readyState == 4) {
                    let tag = e.target.tag;
                    let request = this.#requests[tag];
                    switch (e.target.status) {
                        case 200:
                            if (!this.#isOnline) {
                                this.#log(4, 'Server API connection estabilished');
                                this.#isOnline = true;
                                this.#forceUpdateTorrents();
                            }
                            //request.response = JSON.parse(e.target.responseText);
                            if (request.success != null) {
                                request.success(JSON.parse(e.target.responseText).arguments);
                            }
                            else {
                                //this.#logger(e.target.responseText);
                            }
                            break;
                        case 409:
                            this.#sessionHeader = e.target.getResponseHeader('X-Transmission-Session-Id');
                            this.#rpccall(tag);
                            break;
                        default:
                            request.response = {'code': e.target.status, 'content': e.target.responseText};
                            //this.#logger(JSON.stringify(request.response));
                            break;
                    }
                }
                break;
            case 'timeout':
                if (this.#isOnline) {
                    this.#log(3, 'Server API connection timed out');
                    this.#isOnline = false;
                    this.#forceUpdateTorrents();
                }
                break;
            case 'error':
                if (this.#isOnline) {
                    this.#log(3, 'Server API refuses connection');
                    this.#isOnline = false;
                    this.#forceUpdateTorrents();
                }
                this.#log(5, JSON.stringify(e));
                break;
        }
    }

    #forceUpdateTorrents() {
        for (const control of Object.values(this.#torrentControls)) {
            control.updateDOM();
        }
    }

    #parseTorrents(response) {
        let updatedHashes = [];
        // Update torrent data
        for (const fromserver of response.torrents) {
            let hash = fromserver.hashString;
            let initdata = {};
            for (const [key, value] of Object.entries(fromserver)) {
                let parsedValue = undefined;
                switch (key) {
                    case 'hashString':
                        break;
                    case 'percentDone':
                        parsedValue = Math.floor(value * 100);
                        break;
                    default:
                        parsedValue = value;
                        break;
                }
                
                if (parsedValue != undefined) {
                    initdata[key] = parsedValue;
                }
            }

            let control;
            if (!(hash in this.#torrentControls)) {
                control = new trdom_torrentcontrol(hash, this, initdata, this.#logcb);
                let createControls = new CustomEvent('torrent-initialize', {
                    detail: {
                        torrentHash: hash,
                        torrentControl: control,
                        serverObject: this
                    }
                });
                this.dispatchEvent(createControls);
            }
            else {
                control = this.getControl(hash);
            }
            
            let e = new CustomEvent('torrent-updated', {
                detail: {
                    torrentHash: hash,
                    torrentInfo: initdata
                }
            });
            control.dispatchEvent(e);
            updatedHashes.push(hash);
        }

        for (const [hash, control] of Object.entries(this.#torrentControls)) {
            if (!updatedHashes.includes(hash) && (control.exists)) {
                let e = new CustomEvent('torrent-deleted', {
                    detail: {
                        torrentHash: hash
                    }
                });
                control.dispatchEvent(e);
            }
        }
    }

    refreshTorrentList() {

        let tag = this.#rpccall_prepare('torrent-get', {'fields': ['id', 'hashString', 'name', 'status', 'percentDone', 'comment', 'magnetLink']});
        this.#requests[tag].success = this.#parseTorrents.bind(this);
        this.#rpccall(tag);
    }

    torrent_add_url(url, dontstart, path) {
        let args = {
            'filename': url,
            'paused': dontstart
        };
        if (path != null) {
            args['download-dir'] = path;
        }
        let tag = this.#rpccall_prepare('torrent-add', args);
        this.#rpccall(tag);
    }

    torrent_start(hash) {
        let tag = this.#rpccall_prepare('torrent-start', {'ids':[hash]});
        this.#rpccall(tag);
    }

    torrent_pause(hash) {
        let tag = this.#rpccall_prepare('torrent-stop', {'ids':[hash]});
        this.#rpccall(tag);
    }

    getInstanceData() {
        return {
            'rpcurl': this.#rpcurl,
            'auth': this.#authHeader
        };
    }

    isOnline() {
        return this.#isOnline;
    }
};