cyp/app/js/mpd.js
2020-05-05 23:03:36 +02:00

184 lines
4.6 KiB
JavaScript

import * as parser from "./parser.js";
let ws;
let commandQueue = [];
let current;
let canTerminateIdle = false;
function onMessage(e) {
if (!current) { return; }
let lines = JSON.parse(e.data);
let last = lines.pop();
if (last.startsWith("OK")) {
current.resolve(lines);
} else {
console.warn(last);
current.reject(last);
}
current = null;
setTimeout(processQueue, 0); // after other potential commands are enqueued
}
function onError(e) {
console.error(e);
current && current.reject(e);
ws = null; // fixme
}
function onClose(e) {
console.warn(e);
current && current.reject(e);
ws = null; // fixme
}
function processQueue() {
if (commandQueue.length == 0) {
if (!current) { idle(); } // nothing to do
} else if (current) { // stuff waiting in queue but there is a command under way
if (canTerminateIdle) {
ws.send("noidle");
canTerminateIdle = false;
}
} else { // advance to next command
current = commandQueue.shift();
ws.send(current.cmd);
}
}
async function idle() {
let promise = command("idle stored_playlist playlist player options");
canTerminateIdle = true;
let lines = await promise;
canTerminateIdle = false;
let changed = parser.linesToStruct(lines).changed || [];
changed = [].concat(changed);
if (changed.length > 0) {
// FIXME not on window
window.dispatchEvent(new CustomEvent("idle-change", {detail:changed}));
}
}
export async function command(cmd) {
if (cmd instanceof Array) { cmd = ["command_list_begin", ...cmd, "command_list_end"].join("\n"); }
return new Promise((resolve, reject) => {
commandQueue.push({cmd, resolve, reject});
processQueue();
});
}
export async function status() {
let lines = await command("status");
return parser.linesToStruct(lines);
}
export async function currentSong() {
let lines = await command("currentsong");
return parser.linesToStruct(lines);
}
export async function listQueue() {
let lines = await command("playlistinfo");
return parser.songList(lines);
}
export async function listPlaylists() {
let lines = await command("listplaylists");
let parsed = parser.linesToStruct(lines);
let list = parsed["playlist"];
if (!list) { return []; }
return (list instanceof Array ? list : [list]);
}
export async function listPath(path) {
let lines = await command(`lsinfo "${escape(path)}"`);
return parser.pathContents(lines);
}
export async function listTags(tag, filter = {}) {
let tokens = ["list", tag];
if (Object.keys(filter).length) {
tokens.push(serializeFilter(filter));
let fakeGroup = Object.keys(filter)[0]; // FIXME hack for MPD < 0.21.6
tokens.push("group", fakeGroup);
}
let lines = await command(tokens.join(" "));
let parsed = parser.linesToStruct(lines);
return [].concat(tag in parsed ? parsed[tag] : []);
}
export async function listSongs(filter, window = null) {
let tokens = ["find", serializeFilter(filter)];
window && tokens.push("window", window.join(":"));
let lines = await command(tokens.join(" "));
return parser.songList(lines);
}
export async function searchSongs(filter) {
let tokens = ["search", serializeFilter(filter, "contains")];
let lines = await command(tokens.join(" "));
return parser.songList(lines);
}
export async function albumArt(songUrl) {
let data = [];
let offset = 0;
let params = ["albumart", `"${escape(songUrl)}"`, offset];
while (1) {
params[2] = offset;
try {
let lines = await command(params.join(" "));
data = data.concat(lines[2]);
let metadata = parser.linesToStruct(lines.slice(0, 2));
if (data.length >= Number(metadata["size"])) { return data; }
offset += Number(metadata["binary"]);
} catch (e) { return null; }
}
return null;
}
export function serializeFilter(filter, operator = "==") {
let tokens = ["("];
Object.entries(filter).forEach(([key, value], index) => {
index && tokens.push(" AND ");
tokens.push(`(${key} ${operator} "${escape(value)}")`);
});
tokens.push(")");
let filterStr = tokens.join("");
return `"${escape(filterStr)}"`;
}
export function escape(str) {
return str.replace(/(['"\\])/g, "\\$1");
}
export async function init() {
let response = await fetch("/ticket", {method:"POST"});
let ticket = (await response.json()).ticket;
let resolve, reject;
let promise = new Promise((res, rej) => {
resolve = res;
reject = rej;
try {
let url = new URL(location.href);
url.protocol = "ws";
url.hash = "";
url.searchParams.set("ticket", ticket);
ws = new WebSocket(url.href);
} catch (e) { reject(e); }
ws.addEventListener("error", onError);
ws.addEventListener("message", onMessage);
ws.addEventListener("close", onClose);
});
current = {resolve, reject, promise};
return Promise;
}