@remix-run/headers/dist/lib/content-disposition.js

A toolkit for working with HTTP headers in JavaScript

import {} from "./header-value.js";
import { parseParams, quote } from "./param-values.js";
/**
 * The value of a `Content-Disposition` HTTP header.
 *
 * [MDN `Content-Disposition` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Disposition)
 *
 * [RFC 6266](https://tools.ietf.org/html/rfc6266)
 */
export class ContentDisposition {
    filename;
    filenameSplat;
    name;
    type;
    /**
     * @param init A string or object to initialize the header
     */
    constructor(init) {
        if (init) {
            if (typeof init === 'string') {
                let params = parseParams(init);
                if (params.length > 0) {
                    this.type = params[0][0];
                    for (let [name, value] of params.slice(1)) {
                        if (name === 'filename') {
                            this.filename = value;
                        }
                        else if (name === 'filename*') {
                            this.filenameSplat = value;
                        }
                        else if (name === 'name') {
                            this.name = value;
                        }
                    }
                }
            }
            else {
                this.filename = init.filename;
                this.filenameSplat = init.filenameSplat;
                this.name = init.name;
                this.type = init.type;
            }
        }
    }
    /**
     * The preferred filename for the content, using the `filename*` parameter if present, falling back to the `filename` parameter.
     *
     * From [RFC 6266](https://tools.ietf.org/html/rfc6266):
     *
     * Many user agent implementations predating this specification do not understand the "filename*" parameter.
     * Therefore, when both "filename" and "filename*" are present in a single header field value, recipients SHOULD
     * pick "filename*" and ignore "filename". This way, senders can avoid special-casing specific user agents by
     * sending both the more expressive "filename*" parameter, and the "filename" parameter as fallback for legacy recipients.
     */
    get preferredFilename() {
        let filenameSplat = this.filenameSplat;
        if (filenameSplat) {
            let decodedFilename = decodeFilenameSplat(filenameSplat);
            if (decodedFilename)
                return decodedFilename;
        }
        return this.filename;
    }
    /**
     * Returns the string representation of the header value.
     *
     * @return The header value as a string
     */
    toString() {
        if (!this.type) {
            return '';
        }
        let parts = [this.type];
        if (this.name) {
            parts.push(`name=${quote(this.name)}`);
        }
        if (this.filename) {
            parts.push(`filename=${quote(this.filename)}`);
        }
        if (this.filenameSplat) {
            parts.push(`filename*=${quote(this.filenameSplat)}`);
        }
        return parts.join('; ');
    }
}
function decodeFilenameSplat(value) {
    let match = value.match(/^([\w-]+)'([^']*)'(.+)$/);
    if (!match)
        return null;
    let [, charset, , encodedFilename] = match;
    let decodedFilename = percentDecode(encodedFilename);
    try {
        let decoder = new TextDecoder(charset);
        let bytes = new Uint8Array(decodedFilename.split('').map((char) => char.charCodeAt(0)));
        return decoder.decode(bytes);
    }
    catch (error) {
        console.warn(`Failed to decode filename from charset ${charset}:`, error);
        return decodedFilename;
    }
}
function percentDecode(value) {
    return value.replace(/\+/g, ' ').replace(/%([0-9A-Fa-f]{2})/g, (_, hex) => {
        return String.fromCharCode(parseInt(hex, 16));
    });
}