From 74579ac2f2a4dd46487fb4d2bb2f2b26961a54f1 Mon Sep 17 00:00:00 2001
From: Sebastian <sebasjm@gmail.com>
Date: Mon, 26 Jun 2023 12:54:54 -0300
Subject: [PATCH] withdraw exchange URI

---
 packages/taler-util/src/taleruri.test.ts | 41 +++++++++++++++++
 packages/taler-util/src/taleruri.ts      | 56 ++++++++++++++++++++++++
 2 files changed, 97 insertions(+)

diff --git a/packages/taler-util/src/taleruri.test.ts b/packages/taler-util/src/taleruri.test.ts
index ffc56a723..3244bbbd9 100644
--- a/packages/taler-util/src/taleruri.test.ts
+++ b/packages/taler-util/src/taleruri.test.ts
@@ -22,10 +22,12 @@ import {
   parseRefundUri,
   parseRestoreUri,
   parseTipUri,
+  parseWithdrawExchangeUri,
   parseWithdrawUri,
   stringifyPayPushUri,
   stringifyPayUri,
   stringifyRestoreUri,
+  stringifyWithdrawExchange,
 } from "./taleruri.js";
 
 test("taler pay url parsing: wrong scheme", (t) => {
@@ -329,3 +331,42 @@ test("taler restore URI (stringify)", (t) => {
     "taler://restore/GJKG23V4ZBHEH45YRK7TWQE8ZTY7JWTY5094TQJSRZN5DSDBX8E0/http%3A%2F%2Fprov1.example.com%2F,https%3A%2F%2Fprov2.example.com%3A234%2F",
   );
 });
+
+test("taler withdraw exchange URI (parse)", (t) => {
+  const r1 = parseWithdrawExchangeUri(
+    "taler://withdraw-exchange/exchange.demo.taler.net/someroot/GJKG23V4ZBHEH45YRK7TWQE8ZTY7JWTY5094TQJSRZN5DSDBX8E0?a=KUDOS%3A2",
+  );
+  if (!r1) {
+    t.fail();
+    return;
+  }
+  t.deepEqual(
+    r1.exchangePub,
+    "GJKG23V4ZBHEH45YRK7TWQE8ZTY7JWTY5094TQJSRZN5DSDBX8E0",
+  );
+  t.deepEqual(r1.exchangeBaseUrl, "https://exchange.demo.taler.net/someroot/");
+  t.deepEqual(r1.amount, "KUDOS:2");
+});
+
+test("taler withdraw exchange URI (stringify)", (t) => {
+  const url = stringifyWithdrawExchange({
+    exchangeBaseUrl: "https://exchange.demo.taler.net",
+    exchangePub: "GJKG23V4ZBHEH45YRK7TWQE8ZTY7JWTY5094TQJSRZN5DSDBX8E0",
+  });
+  t.deepEqual(
+    url,
+    "taler://withdraw-exchange/exchange.demo.taler.net/GJKG23V4ZBHEH45YRK7TWQE8ZTY7JWTY5094TQJSRZN5DSDBX8E0",
+  );
+});
+
+test("taler withdraw exchange URI with amount (stringify)", (t) => {
+  const url = stringifyWithdrawExchange({
+    exchangeBaseUrl: "https://exchange.demo.taler.net",
+    exchangePub: "GJKG23V4ZBHEH45YRK7TWQE8ZTY7JWTY5094TQJSRZN5DSDBX8E0",
+    amount: "KUDOS:19",
+  });
+  t.deepEqual(
+    url,
+    "taler://withdraw-exchange/exchange.demo.taler.net/GJKG23V4ZBHEH45YRK7TWQE8ZTY7JWTY5094TQJSRZN5DSDBX8E0?a=KUDOS%3A19",
+  );
+});
diff --git a/packages/taler-util/src/taleruri.ts b/packages/taler-util/src/taleruri.ts
index cb0d74a12..fc140811b 100644
--- a/packages/taler-util/src/taleruri.ts
+++ b/packages/taler-util/src/taleruri.ts
@@ -15,6 +15,7 @@
  */
 
 import { canonicalizeBaseUrl } from "./helpers.js";
+import { AmountString } from "./taler-types.js";
 import { URLSearchParams, URL } from "./url.js";
 
 export type TalerUri =
@@ -28,6 +29,7 @@ export type TalerUri =
   | TipUriResult
   | WithdrawUriResult
   | ExchangeUri
+  | WithdrawExchangeUri
   | AuditorUri;
 
 export interface PayUriResult {
@@ -99,6 +101,13 @@ export interface BackupRestoreUri {
   providers: Array<string>;
 }
 
+export interface WithdrawExchangeUri {
+  type: TalerUriAction.WithdrawExchange;
+  exchangeBaseUrl: string;
+  exchangePub: string;
+  amount?: AmountString;
+}
+
 /**
  * Parse a taler[+http]://withdraw URI.
  * Return undefined if not passed a valid URI.
@@ -166,6 +175,7 @@ export enum TalerUriAction {
   Auditor = "auditor",
   Restore = "restore",
   DevExperiment = "dev-experiment",
+  WithdrawExchange = "withdraw-exchange",
 }
 
 interface TalerUriProtoInfo {
@@ -207,6 +217,7 @@ const parsers: { [A in TalerUriAction]: Parser } = {
   [TalerUriAction.DevExperiment]: parseDevExperimentUri,
   [TalerUriAction.Exchange]: parseExchangeUri,
   [TalerUriAction.Auditor]: parseAuditorUri,
+  [TalerUriAction.WithdrawExchange]: parseWithdrawExchangeUri,
 };
 
 export function parseTalerUri(string: string): TalerUri | undefined {
@@ -253,6 +264,9 @@ export function stringifyTalerUri(uri: TalerUri): string {
     case TalerUriAction.Exchange: {
       return stringifyExchangeUri(uri);
     }
+    case TalerUriAction.WithdrawExchange: {
+      return stringifyWithdrawExchange(uri);
+    }
     case TalerUriAction.Auditor: {
       return stringifyAuditorUri(uri);
     }
@@ -432,6 +446,37 @@ export function parseExchangeUri(s: string): ExchangeUri | undefined {
     exchangePub,
   };
 }
+
+export function parseWithdrawExchangeUri(
+  s: string,
+): WithdrawExchangeUri | undefined {
+  const pi = parseProtoInfo(s, "withdraw-exchange");
+  if (!pi) {
+    return undefined;
+  }
+  const c = pi?.rest.split("?");
+  const parts = c[0].split("/");
+  if (parts.length < 2) {
+    return undefined;
+  }
+  const host = parts[0].toLowerCase();
+  const exchangePub = parts[parts.length - 1];
+  const pathSegments = parts.slice(1, parts.length - 1);
+  const hostAndSegments = [host, ...pathSegments].join("/");
+  const exchangeBaseUrl = canonicalizeBaseUrl(
+    `${pi.innerProto}://${hostAndSegments}/`,
+  );
+  const q = new URLSearchParams(c[1] ?? "");
+  const amount = q.get("a") ?? undefined;
+
+  return {
+    type: TalerUriAction.WithdrawExchange,
+    exchangeBaseUrl,
+    exchangePub,
+    amount,
+  };
+}
+
 export function parseAuditorUri(s: string): AuditorUri | undefined {
   const pi = parseProtoInfo(s, "auditor");
   if (!pi) {
@@ -622,6 +667,17 @@ export function stringifyRestoreUri({
   return `taler://restore/${walletRootPriv}/${list}`;
 }
 
+export function stringifyWithdrawExchange({
+  exchangeBaseUrl,
+  exchangePub,
+  amount,
+}: Omit<WithdrawExchangeUri, "type">): string {
+  const { proto, path, query } = getUrlInfo(exchangeBaseUrl, {
+    a: amount,
+  });
+  return `${proto}://withdraw-exchange/${path}${exchangePub}${query}`;
+}
+
 export function stringifyDevExperimentUri({
   devExperimentId,
 }: Omit<DevExperimentUri, "type">): string {