system repo functions

squarenotsquare/realm/repos/SystemRepo.js

@@ -0,0 +1,64 @@
+import {System} from '../entities/System';
+import uuid from 'uuid';
+
+export default class SystemRepo {
+    realmDB = null;
+
+    constructor(db) {
+        this.realmDB = db;
+    }
+
+    getAllSystemValues = () => {
+        let system = this.realmDB.objects(System.name);
+        let systemValues = {};
+        system.forEach((row) => {
+            systemValues[row.key] = row.value;
+        });
+        return systemValues;
+    };
+
+    createSystemValue = (key, value) => {
+        let sysID = null;
+        let sysKey = key;
+        let sysValue = value;
+    
+        let existing = this.getSystemKeyValue(key);
+    
+        if (existing.id === null) {
+            sysID = uuid.v4();
+        } else {
+            sysID = existing.id;
+        }
+        this.realmDB.write(() => {
+            this.realmDB.create(
+                System.name,
+                {
+                    id: sysID,
+                    key: sysKey,
+                    value: sysValue,
+                },
+                true,
+            );
+        });
+    };
+
+    deleteSystemValue = (key) => {
+        let existingKey = this.getSystemKeyValue(key);
+        if (!existingKey.id === null) {
+            this.realmDB.write(() => {
+                this.realmDB.delete(existingKey);
+            });
+        }
+    };
+
+    getSystemKeyValue = (key) => {
+        let row = this.realmDB.objects(System.name).filtered('key = $0', key);
+        if (row.length === 1) {
+            return {id: row[0].id, value: row[0].value};
+        } else if (row.length > 1) {
+            return 'Multiple system keys found for ' + key;
+        } else {
+            return {id: null, value: null};
+        }
+    };
+}