kea-react/src/mailto.ts

Componentes comunes de react

import { appendEncodedUrlParameters } from "./url";
export interface Mail {
    /**Recipientes To */
    to: string[];
    /**Recipientes CC */
    cc?: string[];
    /**Recipientes BCC */
    bcc?: string[];
    subject?: string;
    body?: string;
}

/**Genera la URL del link para un mailto: */
function generateMailtoLinkNoLengthCheck(mail: Mail) {
    const generateContactList = (contacts: string[]) => contacts.map(x => x.trim()).join(",");
    const base =
        "mailto:" + generateContactList(mail.to);

    const parameters = ([
        { key: "cc", value: generateContactList(mail.cc || []) },
        { key: "bcc", value: generateContactList(mail.bcc || []) },
        { key: "subject", value: encodeURIComponent(mail.subject || "") },
        { key: "body", value: encodeURIComponent(mail.body || "") }
    ]).filter(x => !!x.value);

    const paramStr = parameters.map(x => x.key + "=" + x.value).join("&");
    const url = appendEncodedUrlParameters(base, paramStr);
    return url;
}

function getMailLen(mail: Mail) {
    const getLen = (x: string | string[] | undefined) => {
        if (x == null) return 0;
        if (typeof x == "string") return x.length;
        return x.map(x => x.length).reduce((a, b) => a + b, 0);
    }
    return [mail.bcc, mail.body, mail.cc, mail.subject, mail.to].map(x => getLen(x)).reduce((a, b) => a + b, 0);
}

export function generateMailtoLink(mail: Mail) {
    const maxLen = 2030;

    //Aplicamos una reducción inicial proporcional, intentando atinarle al tamaño del correo

    const cutMail = (len: number): Mail => ({
        ...mail,
        body: (mail.body || "").substr(0, len) + "..."
    });

    let currentMail: Mail = mail;
    let currentUrl = generateMailtoLinkNoLengthCheck(currentMail);
    let bodyLenFix = (mail.body || "").length;
    while (currentUrl.length > maxLen) {
        //Reducir la longitud
        if (bodyLenFix > 0) {
            const mailLen = getMailLen(currentMail);
            //La va reduciendo proporcionalmente en cada paso, eso puede ocasionar que sea reducida de mas pero no importa
            const reduccionProp = (maxLen / currentUrl.length) * (bodyLenFix / mailLen);
            bodyLenFix = Math.ceil(bodyLenFix * reduccionProp) - 1;
        } else {
            break;
        }

        currentMail = cutMail(bodyLenFix);
        currentUrl = generateMailtoLinkNoLengthCheck(currentMail);
    }

    return currentUrl;
}

/**
 * Envia un correo utilizando la directiva mailto
 * @param mail Correo que se desea enviar
 */
export function mailto(mail: Mail) {
    const a = document.createElement("a");
    a.style.display = "none";
    document.body.appendChild(a);

    const url = generateMailtoLink(mail);
    a.target = "_blank";
    a.href = url;
    a.click();

    document.body.removeChild(a);
}