path: root/taler-wallet-lib.ts

/*
  @source https://www.git.taler.net/?p=web-common.git;a=blob_plain;f=taler-wallet-lib.ts;hb=HEAD
  @license magnet:?xt=urn:btih:5de60da917303dbfad4f93fb1b985ced5a89eac2&dn=lgpl-2.1.txt LGPL v21

  @licstart  The following is the entire license notice for the
  JavaScript code in this page.

  Copyright (C) 2015, 2016 INRIA

  The JavaScript code in this page is free software: you can
  redistribute it and/or modify it under the terms of the GNU
  Lesser General Public License (GNU LGPL) as published by the Free Software
  Foundation, either version 2.1 of the License, or (at your option)
  any later version.  The code is distributed WITHOUT ANY WARRANTY;
  without even the implied warranty of MERCHANTABILITY or FITNESS
  FOR A PARTICULAR PURPOSE.  See the GNU LGPL for more details.

  As additional permission under GNU LGPL version 2.1 section 7, you
  may distribute non-source (e.g., minimized or compacted) forms of
  that code without the copy of the GNU LGPL normally required by
  section 4, provided you include this license notice and a URL
  through which recipients can access the Corresponding Source.

  @licend  The above is the entire license notice
  for the JavaScript code in this page.

  @author Marcello Stanisci
  @author Florian Dold
*/

namespace taler {
  "use strict";

  let logVerbose: boolean = false;
  try {
    logVerbose = !!localStorage.getItem("taler-log-verbose");
  } catch (e) {
    // can't read from local storage
  }

  const presentHandlers: any[] = [];
  const absentHandlers: any[] = [];

  // Are we running as the content script of an 
  // extension (and not just from a normal page)?
  let runningInExtension = false;

  let callSeqId = 1;

  let installed = false;
  let probeExecuted = false;
  let pageLoaded = false;

  let errorHandler: any = undefined;

  export function onError(handler: any) {
    if (errorHandler) {
      console.warn("Overriding error handler");
    }
    errorHandler = handler;
  }


  /**
   * Error handler for things that go wrong in the merchant
   * frontend browser code.
   */
  function raise_error(reason: string, detail: any) {
    if (errorHandler) {
      errorHandler(reason, detail);
      return;
    }
    alert(`Failure: ${reason}.  No error handler installed.  Open the developer console for more information.`);
    console.error(reason, detail);
    console.warn("No custom error handler set.");
  }


  function callWallet(funcName: string, args: any, onResult?: any): void {
    const detail = JSON.parse(JSON.stringify(args || {}));
    const callId = callSeqId++;
    detail.callId = callId;
    let onTimeout = () => {
      console.warn("timeout for invocation of " + funcName);
    }
    const timeoutHandle: number = setTimeout(onTimeout, 1000);
    let handler = (evt: CustomEvent) => {
      if (evt.detail.callId !== callId) {
        return;
      }
      if (onResult) {
        onResult(evt.detail);
      }
      clearTimeout(timeoutHandle);
      document.removeEventListener(funcName + "-result", handler);
    };
    document.addEventListener(funcName + "-result", handler);
    const evt = new CustomEvent(funcName, {detail});
    document.dispatchEvent(evt)
  }


  /**
   * Confirm that a reserve was created.
   *
   * Used by tightly integrated bank portals.
   */
  export function confirmReserve(reservePub: string) {
    if (!installed) {
      logVerbose && console.log("delaying confirmReserve");
      taler.onPresent(() => {
        confirmReserve(reservePub);
      });
      return;
    }
    callWallet("taler-confirm-reserve", {reserve_pub: reservePub});
  }


  export function createReserve(callbackUrl: string, amount: any, wtTypes: string[], suggestedExchangeUrl?: string) {
    if (!installed) {
      logVerbose && console.log("delaying createReserve");
      taler.onPresent(() => {
        createReserve(callbackUrl, amount, wtTypes, suggestedExchangeUrl);
      });
      return;
    }
    let args = {
      callback_url: callbackUrl,
      amount: amount,
      wt_types: wtTypes,
      suggested_exchange_url: suggestedExchangeUrl
    };
    callWallet("taler-create-reserve", args);
  }

  export function onPresent(f: any) {
    presentHandlers.push(f);
  }

  export function onAbsent(f: any) {
    absentHandlers.push(f);
  }

  interface PayDetail {
    contract_url?: string;
    offer_url?: string;
  }

  export function pay(p: PayDetail) {
    if (!installed) {
      logVerbose && console.log("delaying call to 'pay' until GNU Taler wallet is present");
      taler.onPresent(() => {
        pay(p);
      });
      return;
    }
    callWallet("taler-pay", p);
  }

  export function refund(refundUrl: string) {
    if (!installed) {
      logVerbose && console.log("delaying call to 'refund' until GNU Taler wallet is present");
      taler.onPresent(() => {
        refund(refundUrl);
      });
      return;
    }
    callWallet("taler-refund", refundUrl);
  }

  export interface AuditorDetail {
    currency: string;
    url: string;
    auditorPub: string;
    expirationStamp: number;
  }


  export function addAuditor(d: AuditorDetail) {
    if (!installed) {
      logVerbose && console.log("delaying call to 'addAuditor' until GNU Taler wallet is present");
      taler.onPresent(() => {
        addAuditor(d);
      });
      return;
    }
    callWallet("taler-add-auditor", d);
  }


  /**
   * Check if an auditor is already added to the wallet.
   *
   * Same-origin restrictions apply.
   */
  export function checkAuditor(url: string): Promise<AuditorDetail|undefined> {
    if (!installed) {
      logVerbose && console.log("delaying call to 'checkAuditor' until GNU Taler wallet is present");
      return new Promise<AuditorDetail|undefined>((resolve, reject) => {
        taler.onPresent(() => {
          resolve(checkAuditor(url));
        });
      });
    }
    return new Promise<AuditorDetail|undefined>((resolve, reject) => {
      taler.onPresent(() => {
        callWallet("taler-check-auditor", url, (x: any) => resolve(x));
      });
    });
  }


  function initTaler() {

    function handleUninstall() {
      installed = false;
      // not really true, but we want "uninstalled" to be shown
      firstTimeoutCalled = true;
      announce();
    }

    function handleProbe() {
      probeExecuted = true;
      if (!installed) {
        logVerbose && console.log("taler install detected");
        installed = true;
        announce();
      }
    }

    function probeTaler() {
      probeExecuted = false;
      var eve = new Event("taler-probe");
      document.dispatchEvent(eve);
    }

    let firstTimeoutCalled = false;

    function onProbeTimeout() {
      if (!probeExecuted) {
        if (installed || !firstTimeoutCalled) {
          installed = false;
          firstTimeoutCalled = true;
          logVerbose && console.log("taler uninstall detected");
          announce();
        }
      }
      // try again, maybe it'll be installed ...
      probeTaler();
    }

    /**
     * Announce presence/absence
     *
     * Only called after document.readyState is at least "interactive".
     */
    function announce() {
      if (!pageLoaded) {
        logVerbose && console.log("page not loaded yet, announcing later");
        return;
      }
      if (installed) {
        logVerbose && console.log("announcing installed");
        for (var i = 0; i < presentHandlers.length; i++) {
          presentHandlers[i]();
        }
      } else {
        if (firstTimeoutCalled) {
          logVerbose && console.log("announcing uninstalled");
          for (var i = 0; i < absentHandlers.length; i++) {
            absentHandlers[i]();
          }
        } else {
          logVerbose && console.log("announcing nothing");
        }
      }
    }

    function onPageLoad() {
      pageLoaded = true;
      // We only start the timeout after the page is interactive.
      window.setInterval(onProbeTimeout, 300);
      announce();
    }
 
    probeTaler();
    document.addEventListener("taler-probe-result", handleProbe, false);
    document.addEventListener("taler-uninstall", handleUninstall, false);
    // Handle the case where the JavaScript is loaded after the page
    // has been loaded for the first time.
    if (document.readyState == "loading") {
      document.addEventListener("DOMContentLoaded", onPageLoad, false);
    } else {
      onPageLoad();
    }
  }

  logVerbose && console.log("running taler-wallet-lib from page");
  initTaler();
}
// @license-end