feat: sell fixed amount token

lnbits/extensions/cashu/mint.py

@@ -71,7 +71,7 @@ async def melt(cashu: Cashu, proofs: List[Proof], invoice: str):
 
     fees_msat = await check_fees(cashu.wallet, invoice_obj)
     assert total_provided >= amount + fees_msat / 1000, Exception(
-        "provided proofs not enough for Lightning payment."
+        f"Provided proofs (${total_provided} sats) not enough for Lightning payment ({amount + fees_msat} sats)."
     )
 
     await pay_invoice(

lnbits/extensions/cashu/mint_helper.py

@@ -33,20 +33,22 @@ def derive_pubkeys(keys: List[PrivateKey]):
 # async required?
 async def verify_proof(master_prvkey: str, proofs_used: Set[str], proof: Proof):
     """Verifies that the proof of promise was issued by this ledger."""
-    # if proof.secret in proofs_used:
-    #     raise Exception(f"tokens already spent. Secret: {proof.secret}")
+    if proof.secret in proofs_used:
+        raise Exception(f"tokens already spent. Secret: {proof.secret}")
 
     secret_key = derive_keys(master_prvkey)[
         proof.amount
     ]  # Get the correct key to check against
     C = PublicKey(bytes.fromhex(proof.C), raw=True)
-    secret = base64.urlsafe_b64decode(proof.secret)
+    secret = base64.standard_b64decode(proof.secret)
     print('### secret', secret)
     validMintSig = verify(secret_key, C, secret)
     if validMintSig != True:
         raise Exception(f"tokens not valid. Secret: {proof.secret}")
 
     
+
+
 def verify_split_amount(amount: int):
     """Split amount like output amount can't be negative or too big."""
     try:

lnbits/extensions/cashu/static/js/base64.js

@@ -1,40 +1,37 @@
-function unescapeBase64Url (str) {
+function unescapeBase64Url(str) {
   return (str + '==='.slice((str.length + 3) % 4))
     .replace(/-/g, '+')
     .replace(/_/g, '/')
-  }
+}
 
-  function escapeBase64Url (str) {
-    return str.replace(/\+/g, '-')
-      .replace(/\//g, '_')
-      .replace(/=/g, '')
-  }
+function escapeBase64Url(str) {
+  return str.replace(/\+/g, '-').replace(/\//g, '_').replace(/=/g, '')
+}
 
-  const uint8ToBase64 = (function (exports) {
-    'use strict';
+const uint8ToBase64 = (function (exports) {
+  'use strict'
 
-    var fromCharCode = String.fromCharCode;
+  var fromCharCode = String.fromCharCode
   var encode = function encode(uint8array) {
-      var output = [];
+    var output = []
 
     for (var i = 0, length = uint8array.length; i < length; i++) {
-        output.push(fromCharCode(uint8array[i]));
+      output.push(fromCharCode(uint8array[i]))
     }
 
-      return btoa(output.join(''));
-    };
+    return btoa(output.join(''))
+  }
 
   var asCharCode = function asCharCode(c) {
-      return c.charCodeAt(0);
-    };
+    return c.charCodeAt(0)
+  }
 
   var decode = function decode(chars) {
-      return Uint8Array.from(atob(chars), asCharCode);
-    };
+    return Uint8Array.from(atob(chars), asCharCode)
+  }
 
-    exports.decode = decode;
-    exports.encode = encode;
+  exports.decode = decode
+  exports.encode = encode
 
-    return exports;
-  
-  }({}));
+  return exports
+})({})

lnbits/extensions/cashu/templates/cashu/wallet.html

@@ -852,19 +852,19 @@ page_container %}
       sellTokens: async function () {
         console.log('#### sell tokens')
         const amount = this.sellData.invoice.sat
-        const token = this.tokens
-          .filter(t => t.promises?.length)
-          .find(t => t.promises.find(b => b.amount === amount))
-        console.log('### token', token)
-        if (token) {
-          const promiseIndex = token.promises
-            .map(p => `${p.amount}`)
-            .indexOf(`${amount}`)
-          const promise = token.promises[promiseIndex]
+        const paidTokens = this.tokens.filter(t => t.promises?.length)
+        console.log('### paidTokens', paidTokens)
+        const proofs = paidTokens.map(token => {
+          // const promiseIndex = token.promises
+          //   .map(p => `${p.amount}`)
+          //   .indexOf(`${amount}`)
+          return token.promises.map((promise, promiseIndex) => {
+            // const promise = token.promises[promiseIndex]
             console.log('### promise', promise)
 
             const secret = token.secrets[promiseIndex]
-          const randomBlindingFactor = token.randomBlindingFactors[promiseIndex]
+            const randomBlindingFactor =
+              token.randomBlindingFactors[promiseIndex]
 
             const C_ = nobleSecp256k1.Point.fromHex(promise['C_'])
             const A = this.keys[promise.amount] // todo
@@ -878,21 +878,19 @@ page_container %}
               nobleSecp256k1.Point.fromHex(A)
             )
 
-          const proofs = [
-            {
-              amount,
+            return {
+              amount: promise.amount,
               secret,
               C: C.toHex(true)
             }
-          ]
-
+          })
+        })
         const payload = {
-            proofs,
+          proofs: proofs.flat(),
           amount,
           invoice: this.sellData.bolt11
         }
         console.log('#### payload', JSON.stringify(payload))
-        }
       },
 
       fetchMintKeys: async function () {