Files
genieacs/ui/datalist.ts

63 lines
1.8 KiB
TypeScript

/**
* Copyright 2013-2021 GenieACS Inc.
*
* This file is part of GenieACS.
*
* GenieACS is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* GenieACS is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with GenieACS. If not, see <http://www.gnu.org/licenses/>.
*/
import m, { ClosureComponent, Component, Vnode } from "mithril";
const elements: Map<string, Vnode> = new Map();
// Source: https://werxltd.com/wp/2010/05/13/javascript-implementation-of-javas-string-hashcode-method/
function hash(str: string): number {
let res = 0;
for (let i = 0; i < str.length; ++i) {
const c = str.charCodeAt(i);
res = (res << 5) - res + c;
res |= 0;
}
return res;
}
export function getDatalistId(options: string[]): string {
const id = "datalist" + options.reduce((acc, cur) => acc ^ hash(cur), 0);
if (!elements.has(id)) {
const n = m(
"datalist",
{ id },
options.map((o) => m("option", { value: o }))
);
elements.set(id, n);
}
return id;
}
const component: ClosureComponent = (): Component => {
return {
view: () => {
return [...elements.values()];
},
onupdate: () => {
for (const id of elements.keys()) {
const used = document.querySelector(`[list='${id}']`);
if (!used) elements.delete(id);
}
},
};
};
export default component;