add full version debts system

foundation for granting the full version while consuming the same amount
automatically at the next purchase

src/api/admin.ts

@@ -1,6 +1,6 @@
 /*
  * server component for the TimeLimit App
- * Copyright (C) 2019 - 2022 Jonas Lochmann
+ * Copyright (C) 2019 - 2026 Jonas Lochmann
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
@@ -228,7 +228,10 @@ export const createAdminRouter = ({ database, websocket, eventHandler }: {
             error: 'family not found'
           }
 
-          const canDoPurchase = canDoNextPurchase({ fullVersionUntil: parseInt(familyEntry.fullVersionUntil) })
+          const canDoPurchase = canDoNextPurchase({
+            fullVersionUntil: parseInt(familyEntry.fullVersionUntil),
+            fullVersionDebts: parseInt(familyEntry.fullVersionDebts),
+          })
 
           if (!canDoPurchase) {
             const lastPurchase = await database.purchase.findOne({

src/api/purchase.ts

@@ -1,6 +1,6 @@
 /*
  * server component for the TimeLimit App
- * Copyright (C) 2019 - 2022 Jonas Lochmann
+ * Copyright (C) 2019 - 2026 Jonas Lochmann
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
@@ -54,7 +54,10 @@ export const createPurchaseRouter = ({ database, websocket }: {
           transaction
         })
 
-        return canDoNextPurchase({ fullVersionUntil: parseInt(familyEntry.fullVersionUntil, 10) })
+        return canDoNextPurchase({
+          fullVersionUntil: parseInt(familyEntry.fullVersionUntil, 10),
+          fullVersionDebts: parseInt(familyEntry.fullVersionDebts, 10),
+        })
       })
 
       res.json({

src/database/family.ts

@@ -1,6 +1,6 @@
 /*
  * server component for the TimeLimit App
- * Copyright (C) 2019 - 2022 Jonas Lochmann
+ * Copyright (C) 2019 - 2026 Jonas Lochmann
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
@@ -37,8 +37,13 @@ export interface FamilyAttributesVersion3 {
   u2fKeysVersion: string
 }
 
+export interface FamilyAttributesVersion4 {
+  fullVersionDebts: string
+}
+
 export type FamilyAttributes = FamilyAttributesVersion1 &
-  FamilyAttributesVersion2 & FamilyAttributesVersion3
+  FamilyAttributesVersion2 & FamilyAttributesVersion3 &
+  FamilyAttributesVersion4
 
 export type FamilyModel = Sequelize.Model<FamilyAttributes> & FamilyAttributes
 export type FamilyModelStatic = typeof Sequelize.Model & {
@@ -76,10 +81,22 @@ export const attributesVersion3: SequelizeAttributes<FamilyAttributesVersion3> =
   }
 }
 
+export const attributesVersion4: SequelizeAttributes<FamilyAttributesVersion4> = {
+  fullVersionDebts: {
+    type: Sequelize.BIGINT,
+    allowNull: false,
+    defaultValue: 0,
+    validate: {
+      min: 0
+    }
+  }
+}
+
 export const attributes: SequelizeAttributes<FamilyAttributes> = {
   ...attributesVersion1,
   ...attributesVersion2,
-  ...attributesVersion3
+  ...attributesVersion3,
+  ...attributesVersion4
 }
 
 export const createFamilyModel = (sequelize: Sequelize.Sequelize): FamilyModelStatic => sequelize.define('Family', attributes) as FamilyModelStatic

src/database/migration/migrations/20260712-add-family-full-version-debts.ts

@@ -0,0 +1,39 @@
+/*
+ * server component for the TimeLimit App
+ * Copyright (C) 2019 - 2026 Jonas Lochmann
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, version 3 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+import { QueryInterface, Sequelize, Transaction } from 'sequelize'
+import { attributesVersion4 as familyAttributes } from '../../family'
+
+export async function up (queryInterface: QueryInterface, sequelize: Sequelize) {
+  await sequelize.transaction({
+    type: Transaction.TYPES.EXCLUSIVE
+  }, async (transaction) => {
+    await queryInterface.addColumn('Families', 'fullVersionDebts', {
+      ...familyAttributes.fullVersionDebts
+    }, {
+      transaction
+    })
+  })
+}
+
+export async function down (queryInterface: QueryInterface, sequelize: Sequelize) {
+  await sequelize.transaction({
+    type: Transaction.TYPES.EXCLUSIVE
+  }, async (transaction) => {
+    await queryInterface.removeColumn('Families', 'fullVersionDebts', { transaction })
+  })
+}

src/function/parent/create-family.ts

@@ -1,6 +1,6 @@
 /*
  * server component for the TimeLimit App
- * Copyright (C) 2019 - 2022 Jonas Lochmann
+ * Copyright (C) 2019 - 2026 Jonas Lochmann
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
@@ -82,7 +82,8 @@ export async function createFamily ({
       fullVersionUntil: (Date.now() + 1000 * 60 * 60 * 24 * 14).toString(10),
       hasFullVersion: true,
       nextServerKeyRequestSeq: '1',
-      u2fKeysVersion: generateVersionId()
+      u2fKeysVersion: generateVersionId(),
+      fullVersionDebts: '0'
     }, { transaction })
 
     // create parent user

src/function/purchase/add-purchase.ts

@@ -1,6 +1,6 @@
 /*
  * server component for the TimeLimit App
- * Copyright (C) 2019 - 2022 Jonas Lochmann
+ * Copyright (C) 2019 - 2026 Jonas Lochmann
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
@@ -57,11 +57,19 @@ export const addPurchase = async ({ database, familyId, type, service, transacti
   }
 
   const previousFullVersionEndTime = familyEntry.fullVersionUntil
+  const previousFullVersionDebts = parseInt(familyEntry.fullVersionDebts, 10)
 
-  const newFullVersionUntil = Math.max(parseInt(familyEntry.fullVersionUntil, 10), Date.now()) + (type === 'year' ? year : month)
+  const typeDuration = type === 'year' ? year : month
+
+  if (typeDuration > previousFullVersionDebts) {
+    const newFullVersionUntil = Math.max(parseInt(familyEntry.fullVersionUntil, 10), Date.now()) + typeDuration - previousFullVersionDebts
 
     familyEntry.fullVersionUntil = newFullVersionUntil.toString(10)
+    familyEntry.fullVersionDebts = '0'
     familyEntry.hasFullVersion = true
+  } else {
+    familyEntry.fullVersionDebts = (previousFullVersionDebts - typeDuration).toString(10)
+  }
 
   await familyEntry.save({ transaction })
 
@@ -72,7 +80,7 @@ export const addPurchase = async ({ database, familyId, type, service, transacti
     type,
     loggedAt: Date.now().toString(10),
     previousFullVersionEndTime,
-    newFullVersionEndTime: newFullVersionUntil.toString(10)
+    newFullVersionEndTime: familyEntry.fullVersionUntil
   }, {
     transaction
   })

src/function/purchase/can-do-next-purchase.ts

@@ -1,6 +1,6 @@
 /*
  * server component for the TimeLimit App
- * Copyright (C) 2019 Jonas Lochmann
+ * Copyright (C) 2019 - 2026 Jonas Lochmann
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
@@ -15,6 +15,9 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
-export const canDoNextPurchase = ({ fullVersionUntil }: {fullVersionUntil: number}) => (
-  fullVersionUntil < (Date.now() + 1000 * 60 * 60 * 24 * 31)  // 31 days
+export const canDoNextPurchase = ({ fullVersionUntil, fullVersionDebts }: {
+  fullVersionUntil: number
+  fullVersionDebts: number
+}) => (
+  (fullVersionUntil - fullVersionDebts) < (Date.now() + 1000 * 60 * 60 * 24 * 31)  // 31 days
 )

src/function/purchase/require-family-entry.ts

@@ -1,6 +1,6 @@
 /*
  * server component for the TimeLimit App
- * Copyright (C) 2019 - 2020 Jonas Lochmann
+ * Copyright (C) 2019 - 2026 Jonas Lochmann
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
@@ -43,7 +43,7 @@ export const requireFamilyEntry = async ({ database, deviceAuthToken, transactio
     where: {
       familyId: deviceEntry.familyId
     },
-    attributes: ['fullVersionUntil'],
+    attributes: ['fullVersionUntil', 'fullVersionDebts'],
     transaction
   })
 
@@ -52,7 +52,8 @@ export const requireFamilyEntry = async ({ database, deviceAuthToken, transactio
   }
 
   const familyEntry = {
-    fullVersionUntil: familyEntryUnsafe.fullVersionUntil
+    fullVersionUntil: familyEntryUnsafe.fullVersionUntil,
+    fullVersionDebts: familyEntryUnsafe.fullVersionDebts,
   }
 
   return familyEntry