export default class App {
    input: HTMLInputElement;
    outputContainer: HTMLTextAreaElement;

    constructor() {
        this.input = document.getElementById('in') as HTMLInputElement;
        this.outputContainer = document.getElementById('out') as HTMLTextAreaElement;
        (document.getElementById("run") as HTMLButtonElement).onclick = this.run.bind(this);
    }

    async run() {
        const promises: Promise<string>[] = [];
        for (const file of this.input.files!) {
            promises.push(this.parseFile(file));
        }

        const parts = await Promise.all(promises);

        const output = new Blob([parts.join(' ')], { type: 'text/plain' });
        const a = document.createElement('a');
        a.href = URL.createObjectURL(output);
        a.download = "result.txt";
        a.click();
    }

    async parseFile(file: File) {
        const xml = await file.text();
        const parser = new DOMParser();
        const doc = parser.parseFromString(xml, "text/xml");

        const results: string[] = [];

        for (const node of doc.getElementsByTagNameNS('*', 'tartalom')) {
            let resolve: (value: string) => void, reject: (reason?: any) => void;
            const resultPromise = new Promise<string>((res, rej) => {
                resolve = res, reject = rej;
            });

            const worker = new Worker('worker.js');

            worker.onmessage = (e) => {
                resolve(e.data);
            };

            worker.onerror = (e) => {
                reject(e.error);
            }

            worker.postMessage(node.textContent);

            try {
                results.push(await resultPromise);
            } catch (e) {
                console.error(e);
            }
        }

        return results.join(' ');
    }
}

new App();