venture mdecks: backend client

ventures/mdecks/time.js

@@ -1,24 +1,44 @@
 /* Time's backend client for a venture page. Written by Time next to index.html; the build never edits it.
-   Every call resolves to null when the backend can't help (no network, over the daily limit, or the page is being
-   checked locally), so a product uses these only for extras and works fully without them.
-     Time.save(obj)              -> a share link (string) or null
+   Every call resolves to null (or false) when the backend can't help (no network, over the daily limit, or the page is
+   being checked locally), so a product uses these only for extras and works fully without them.
+     Time.save(obj)              -> a share link (string) or null; when someone is signed in it is also theirs
      Time.load()                 -> the object a share link (?s=...) carried, or null
      Time.ai(prompt, {system})   -> text from a small model, or null
-     Time.ready                  -> a promise of true when the backend answers */
+     Time.ready                  -> a promise of true when the backend answers
+   Accounts, with passkeys (Face ID, Touch ID, Windows Hello, a phone): no passwords, no email.
+     Time.accounts               -> true when this page can sign people in (its own domain, a browser with passkeys)
+     Time.user()                 -> { id, name } of whoever is signed in, or null
+     Time.signUp(name)           -> makes an account with a new passkey and signs in: { id, name } or null
+     Time.signIn()               -> signs in with a passkey made here before: { id, name } or null
+     Time.signOut()              -> true
+     Time.mine()                 -> [{ id, link, created }] the signed-in person saved, or null */
 (function () {
   var API = "https://mdecks.yolopreneur.lol/api/";
   var local = /^(localhost|127\.|\[::1\]|0\.0\.0\.0)/.test(location.hostname) || location.protocol === "file:";
+  var home = API.replace(/\/api\/?$/, "");
+  var accounts = !local && location.origin === home.replace(/\/$/, "") && !!window.PublicKeyCredential;
 
   function call(path, init) {
     if (local) return Promise.resolve(null);
     return fetch(API + path, init).then(function (r) { return r.ok ? r.json() : null; }).catch(function () { return null; });
   }
   function post(path, body) {
-    return call(path, { method: "POST", headers: { "content-type": "application/json" }, body: JSON.stringify(body) });
+    return call(path, { method: "POST", headers: { "content-type": "application/json" }, body: JSON.stringify(body || {}) });
   }
+  function bytes(s) {
+    s = s.replace(/-/g, "+").replace(/_/g, "/");
+    return Uint8Array.from(atob(s + "===".slice((s.length + 3) % 4)), function (c) { return c.charCodeAt(0); });
+  }
+  function text(buf) {
+    var b = new Uint8Array(buf), s = "";
+    for (var i = 0; i < b.length; i++) s += String.fromCharCode(b[i]);
+    return btoa(s).replace(/\+/g, "-").replace(/\//g, "_").replace(/=+$/, "");
+  }
+  function user(r) { return r && r.user ? r.user : null; }
 
   window.Time = {
     api: API,
+    accounts: accounts,
     ready: call("health").then(function (r) { return !!(r && r.ok); }),
     save: function (obj) {
       return post("items", obj).then(function (r) { return r && r.link ? r.link : null; });
@@ -30,6 +50,45 @@
     ai: function (prompt, opts) {
       return post("ai", { prompt: String(prompt || ""), system: opts && opts.system })
         .then(function (r) { return r && typeof r.text === "string" ? r.text : null; });
+    },
+    user: function () {
+      return accounts ? call("auth/me").then(user) : Promise.resolve(null);
+    },
+    signUp: function (name) {
+      if (!accounts) return Promise.resolve(null);
+      return post("auth/register/start", { name: name }).then(function (o) {
+        if (!o) return null;
+        var pk = o.publicKey;
+        pk.challenge = bytes(pk.challenge);
+        pk.user.id = bytes(pk.user.id);
+        return navigator.credentials.create({ publicKey: pk }).then(function (c) {
+          var r = c.response;
+          return post("auth/register/finish", {
+            challengeId: o.challengeId, id: text(c.rawId), clientDataJSON: text(r.clientDataJSON),
+            authenticatorData: text(r.getAuthenticatorData()), publicKey: text(r.getPublicKey()), alg: r.getPublicKeyAlgorithm()
+          }).then(user);
+        });
+      }).catch(function () { return null; });
+    },
+    signIn: function () {
+      if (!accounts) return Promise.resolve(null);
+      return post("auth/login/start").then(function (o) {
+        if (!o) return null;
+        o.publicKey.challenge = bytes(o.publicKey.challenge);
+        return navigator.credentials.get({ publicKey: o.publicKey }).then(function (c) {
+          var r = c.response;
+          return post("auth/login/finish", {
+            challengeId: o.challengeId, id: text(c.rawId), clientDataJSON: text(r.clientDataJSON),
+            authenticatorData: text(r.authenticatorData), signature: text(r.signature)
+          }).then(user);
+        });
+      }).catch(function () { return null; });
+    },
+    signOut: function () {
+      return accounts ? post("auth/logout").then(function () { return true; }) : Promise.resolve(true);
+    },
+    mine: function () {
+      return accounts ? call("me/items").then(function (r) { return r && r.items ? r.items : null; }) : Promise.resolve(null);
     }
   };
 })();