Added withdrawal fee credits, which can pay withdrawal fees

3 files changed, 67 insertions, 36 deletions

diff --git a/db/models/accounts.js b/db/models/accounts.js
index 12fef548..88ad2d44 100644
--- a/db/models/accounts.js
+++ b/db/models/accounts.js
@@ -124,6 +124,15 @@ const attributes = {
     comment: null,
     field: "balance"
   },
+  fee_credits: {
+    type: DataTypes.DOUBLE,
+    allowNull: true,
+    defaultValue: 0.0,
+    primaryKey: false,
+    autoIncrement: false,
+    comment: "Credits that can be used towards paying withdrawal fees",
+    field: "fee_credits"
+  },
   pending: {
     type: DataTypes.DOUBLE,
     allowNull: true,
diff --git a/routes/bitcoin/send.js b/routes/bitcoin/send.js
index aa3a7640..efcedb38 100644
--- a/routes/bitcoin/send.js
+++ b/routes/bitcoin/send.js
@@ -34,7 +34,7 @@ module.exports = ah(async (req, res) => {
   // get withdrawal fee
   // 'total' refers to the total before the withdrawal fee
   // (i.e. the total bitcoin that leaves this server)
-  let withdrawalFee = amount * withdrawalFeeMultiplier;
+  let withdrawalFee = Math.floor(amount * withdrawalFeeMultiplier);
 
   try {
     // withdraw bitcoin
@@ -67,6 +67,14 @@ module.exports = ah(async (req, res) => {
         throw new Error("low balance (after withdrawal fee)");
       }
 
+      // use user's credits to reduce fee, if available
+      console.log(account.fee_credits);
+      let withdrawalFeeDeduction = Math.min(account.fee_credits, withdrawalFee);
+      if (withdrawalFeeDeduction) {
+        await account.decrement({ fee_credits: withdrawalFeeDeduction }, { transaction });
+        await account.reload({ transaction });
+      }
+
       await account.decrement({ balance: (total + withdrawalFee) }, { transaction });
       await account.reload({ transaction });
 
@@ -84,22 +92,24 @@ module.exports = ah(async (req, res) => {
         transaction
       });
 
-      await receiverAccount.increment({ balance: withdrawalFee }, { transaction });
-      await receiverAccount.reload({ transaction });
-      let fee_payment = await db.Payment.create({
-        amount: withdrawalFee,
-        fee: 0,
-        memo: "Bitcoin withdrawal fee",
-        account_id: receiverAccount.id,
-        user_id: receiverAccount.user_id,
-        rate: app.get("rates")[receiverAccount.user.currency],
-        currency: receiverAccount.user.currency,
-        confirmed: true,
-        received: true,
-        network: "COINOS"
-        },
-        { transaction }
-      );
+      let fee_payment_id = null;
+      if (withdrawalFee) {
+        await receiverAccount.increment({ balance: withdrawalFee }, { transaction });
+        await receiverAccount.reload({ transaction });
+        let fee_payment = await db.Payment.create({
+          amount: withdrawalFee,
+          fee: 0,
+          memo: "Bitcoin withdrawal fee",
+          account_id: receiverAccount.id,
+          user_id: receiverAccount.user_id,
+          rate: app.get("rates")[receiverAccount.user.currency],
+          currency: receiverAccount.user.currency,
+          confirmed: true,
+          received: true,
+          network: "COINOS"
+        }, { transaction });
+        fee_payment_id = fee_payment.id;
+      }
 
       // record the external bitcoin transaction
       let params = {
@@ -114,7 +124,7 @@ module.exports = ah(async (req, res) => {
         confirmed: true,
         received: false,
         network: "bitcoin",
-        fee_payment_id: fee_payment.id
+        fee_payment_id: fee_payment_id
       };
 
       if (config.bitcoin.walletpass)
diff --git a/routes/liquid/send.js b/routes/liquid/send.js
index 1e4c62d2..8e21e4d4 100644
--- a/routes/liquid/send.js
+++ b/routes/liquid/send.js
@@ -87,7 +87,7 @@ sendLiquid = async ({ asset, amount, user, address, memo, tx, limit }) => {
         // get withdrawal fee
         // 'total' refers to the total before the withdrawal fee
         // (i.e. the total liquid bitcoin that leaves this server)
-        var withdrawalFee = amount * withdrawalFeeMultiplier;
+        var withdrawalFee = Math.floor(amount * withdrawalFeeMultiplier);
 
         if (limit && total > limit + fee)
           throw new Error("Tx amount exceeds authorized amount");
@@ -131,6 +131,14 @@ sendLiquid = async ({ asset, amount, user, address, memo, tx, limit }) => {
             );
           }
 
+          // use user's credits to reduce fee, if available
+          console.log(account.fee_credits);
+          let withdrawalFeeDeduction = Math.min(account.fee_credits, withdrawalFee);
+          if (withdrawalFeeDeduction) {
+            await account.decrement({ fee_credits: withdrawalFeeDeduction }, { transaction });
+            await account.reload({ transaction });
+          }
+
           await account.decrement({ balance: (total + withdrawalFee)}, { transaction });
           await account.reload({ transaction });
 
@@ -148,22 +156,26 @@ sendLiquid = async ({ asset, amount, user, address, memo, tx, limit }) => {
             transaction
           });
 
-          await receiverAccount.increment({ balance: withdrawalFee }, { transaction });
-          await receiverAccount.reload({ transaction });
-          let fee_payment = {
-            amount: withdrawalFee,
-            fee: 0,
-            memo: "Liquid withdrawal fee",
-            account_id: receiverAccount.id,
-            user_id: receiverAccount.user_id,
-            rate: app.get("rates")[receiverAccount.user.currency],
-            currency: receiverAccount.user.currency,
-            confirmed: true,
-            received: true,
-            network: "COINOS"
-          };
-          fee_payment.account = receiverAccount;
-          payments.push(fee_payment);
+          let fee_payment_id = null;
+          if (withdrawalFee) {
+            await receiverAccount.increment({ balance: withdrawalFee }, { transaction });
+            await receiverAccount.reload({ transaction });
+            let fee_payment = {
+              amount: withdrawalFee,
+              fee: 0,
+              memo: "Liquid withdrawal fee",
+              account_id: receiverAccount.id,
+              user_id: receiverAccount.user_id,
+              rate: app.get("rates")[receiverAccount.user.currency],
+              currency: receiverAccount.user.currency,
+              confirmed: true,
+              received: true,
+              network: "COINOS"
+            };
+            fee_payment.account = receiverAccount;
+            payments.push(fee_payment);
+            fee_payment_id = fee_payment.id;
+          }
 
           let payment = {
             amount: -amount,
@@ -177,7 +189,7 @@ sendLiquid = async ({ asset, amount, user, address, memo, tx, limit }) => {
             confirmed: true,
             received: false,
             network: "liquid",
-            fee_payment_id: fee_payment.id
+            fee_payment_id: fee_payment_id
           };
 
           payment.account = account;