From b618b1aa41b8a10d96d42556d2b00affdb4cf04d Mon Sep 17 00:00:00 2001
From: callebtc <93376500+callebtc@users.noreply.github.com>
Date: Sun, 28 Aug 2022 19:16:23 +0200
Subject: [PATCH] create invoices

---
 internal/api/userpage/static/webapp.html | 92 +++++++++++++++++++-----
 internal/api/userpage/userpage.go        |  3 +-
 2 files changed, 77 insertions(+), 18 deletions(-)
diff --git a/internal/api/userpage/static/webapp.html b/internal/api/userpage/static/webapp.html
index 29499d7..00bbe57 100644
--- a/internal/api/userpage/static/webapp.html
+++ b/internal/api/userpage/static/webapp.html
@@ -58,6 +58,16 @@
             pointer-events: none;
         }
 
+        input {
+            font-size: 14px;
+            text-align: center; 
+            padding: 12px 20px;
+            border: none;
+            border-radius: 4px;
+            background-color: var(--tg-theme-button-color, #f5f5f5);
+            color: var(--tg-theme-button-text-color, #1a1a1a);
+        }
+
         section {
             padding: 5px 5px 65px;
             text-align: center;
@@ -200,13 +210,19 @@
         width: 100% !important;
         height: 100% !important;
         }
+
+        .wrapper {
+        display: grid;
+        grid-template-columns: 1fr 1fr;
+        padding: 12px 20px;
+        }
     </style>
 </head>
 
 <body>
 
 <section>
-    <h1>{{.Username}}@ln.tips</h1>
+    <h1 id="greeting"></h1>
 
     <div class="qr-container">
         <div class="qr" id="qr">
@@ -214,32 +230,35 @@
     </div>
 
     <div id="buttons">
-        <button onclick="webviewClose();">Close</button>
+        <!-- <button onclick="webviewClose();">Close</button> -->
+        <div class="wrapper">
+            <div>
+                <input type="number" id="invoiceAmount" placeholder="1000 sat"></input>
+            </div>
+            <div>
+                <button onclick="getInvoice(this, {{.Callback}});" style="display: inline; margin: 0px;">Invoice</button>
+            </div>
+        </div>
     </div>
 </section>
 
 <script type="application/javascript">
     Telegram.WebApp.ready();
 
-    const qr = document.getElementById('qr');
-    if ( qr ) {
-    const qrGfx = kjua({
-        text: {{.LNURLPay}},
-        rounded: 50,
-        size: 500,
-        render: 'canvas',
-    });
-    qr.appendChild( qrGfx );
-    }
-
+    // render the LNURL pay QR code
+    var s = {{.LNURLPay}};
+    renderQr(s);
+    
+    // data passed form telegram server
     const initData = Telegram.WebApp.initData || '';
     const initDataUnsafe = Telegram.WebApp.initDataUnsafe || {};
 
-    document.querySelector('#greeting').innerHTML = `Hi, ${initDataUnsafe.user.first_name}!`;
-    document.querySelector('#initData').innerHTML = JSON.stringify(initData, null, 2);
-    document.querySelector('#initDataUnsafe').innerHTML = JSON.stringify(initDataUnsafe, null, 2);
-    document.querySelector('#themeData').html(JSON.stringify(Telegram.WebApp.themeParams, null, 2));
+    document.querySelector('#greeting').innerHTML = "{{.Username}}@ln.tips";
+    // document.querySelector('#initData').innerHTML = JSON.stringify(initData, null, 2);
+    // document.querySelector('#initDataUnsafe').innerHTML = JSON.stringify(initDataUnsafe, null, 2);
 
+    // react to theme changes
+    document.querySelector('#themeData').html(JSON.stringify(Telegram.WebApp.themeParams, null, 2));
     Telegram.WebApp.onEvent('themeChanged', function() {
         document.querySelector('#themeData').innerHTML = JSON.stringify(Telegram.WebApp.themeParams, null, 2);
     });
@@ -247,6 +266,45 @@
     function webviewClose() {
         Telegram.WebApp.close();
     }
+
+    function renderQr(payload) {
+        const qr = document.getElementById('qr');
+        qr.innerHTML = '';
+        if ( qr ) {
+        const qrGfx = kjua({
+            text: payload,
+            rounded: 50,
+            size: 500,
+            render: 'canvas',
+        });
+        qr.appendChild( qrGfx );
+        }
+    }
+
+    function getInvoice(el, callback) {
+        fetch(callback)
+        .then(data => {
+            return data.json();
+        })
+        .then(r => {
+            console.log(r);
+            var invoiceAmount = document.getElementById("invoiceAmount").value;
+            if (invoiceAmount == "") {
+                invoiceAmount = 1000; 
+                console.warn("overwriting invoiceAmount with " + invoiceAmount);
+            }
+            console.log("requesting invoice with amount " + invoiceAmount);
+            fetch(r.callback + '?amount='+ invoiceAmount * 1000).then(data => {
+            return data.json();
+            })
+            .then(r => { 
+                console.log(r);
+                // update qr code
+                renderQr(r.pr);
+                document.querySelector('#greeting').innerHTML = "Pay " + invoiceAmount + " sat"
+            })
+        })
+    }
 </script>
 </body>
 </html>
diff --git a/internal/api/userpage/userpage.go b/internal/api/userpage/userpage.go
index b8383e9..39229f0 100644
--- a/internal/api/userpage/userpage.go
+++ b/internal/api/userpage/userpage.go
@@ -105,7 +105,8 @@ func (s Service) UserWebAppHandler(w http.ResponseWriter, r *http.Request) {
 	if err := qr_tmpl.ExecuteTemplate(w, "webapp", struct {
 		Username string
 		LNURLPay string
-	}{username, lnurlEncode}); err != nil {
+		Callback string
+	}{username, lnurlEncode, callback}); err != nil {
 		log.Errorf("failed to render template")
 	}
 }
