helper methods in versioned store

src/lib/storage/VideoProgress.js

@@ -32,7 +32,6 @@ version 0
 }
 */
 
-// TODO implement the store into the rest of the codebase
 export const VideoProgressStore = versionedStoreBuilder()
     .setKey('video-progress')
     .addVersion({

src/lib/storage/base.js

@@ -1,13 +1,17 @@
-function buildStoreObject(data) {
-    return {
-        versions: data.versions,
-        currentVersion: data.maxVersion,
-        id: data.storageString,
-        update(obj) {
+function buildStoreObject(d) {
+    const data = {
+        versions: d.versions,
+        currentVersion: d.maxVersion,
+        id: d.storageString,
+    }
+
+    function update(obj) {
         if (!obj)
             throw new Error("object to update is not an object");
 
         // repeat until object fully updated
+        if (obj["--version"] === undefined)
+            obj["--version"] = 0;
         while (obj["--version"] !== this.currentVersion) {
             // get version
             let version = obj["--version"] || 0;
@@ -16,6 +20,7 @@ function buildStoreObject(data) {
             else {
                 version = (version+1).toString()
             }
+            console.log(this, version);
             
             // check if version exists
             if (!this.versions[version]) {
@@ -37,14 +42,9 @@ function buildStoreObject(data) {
 
         // updates succesful, return
         return obj;
-        },
+    }
 
-        /*
-         * get a instance of a stored item
-         * will be migrated to the latest version on fetch
-         * call .save() on it put the new modified data back
-        */
-        get() {
+    function get() {
         // get from storage api
         const store = this;
         let data = localStorage.getItem(this.id);
@@ -81,10 +81,29 @@ function buildStoreObject(data) {
             localStorage.setItem(store.id, JSON.stringify(data));
         }
         
+        // add instance helpers
+        Object.entries(d.instanceHelpers).forEach(([name, helper]) => {
+            if (data[name] !== undefined)
+                throw new Error(`helper name: ${name} on instance of store ${this.id} is reserved`)
+            data[name] = helper.bind(data);
+        })
+
         // return data
         return data;
     }
-    }
+
+    // add functions to store
+    data.get = get.bind(data);
+    data.update = update.bind(data);
+
+    // add static helpers
+    Object.entries(d.staticHelpers).forEach(([name, helper]) => {
+        if (data[name] !== undefined)
+            throw new Error(`helper name: ${name} on store ${data.id} is reserved`)
+        data[name] = helper.bind({});
+    })
+
+    return data;
 }
 
 /*
@@ -99,6 +118,8 @@ export function versionedStoreBuilder() {
             maxVersion: 0,
             versions: {},
             storageString: null,
+            instanceHelpers: {},
+            staticHelpers: {},
         },
 
         /*
@@ -147,6 +168,38 @@ export function versionedStoreBuilder() {
             return this;
         },
 
+        /*
+         * register a instance or static helper to the store 
+         *
+         * name: name of the helper function
+         * helper: function to execute, the 'this' context is the current storage item (type is instance)
+         * type: "instance" or "static". instance is put on the storage item when you store.get() it, static is on the store
+        */
+        registerHelper({ name, helper, type }) {
+            // type
+            if (!type)
+                type = "instance"
+
+            // input checking
+            if (!name || name.constructor !== String) {
+                throw new Error("helper name is not a string")
+            }
+            if (!helper || helper.constructor !== Function) {
+                throw new Error("helper function is not a function")
+            }
+            if (!["instance", "static"].includes(type)) {
+                throw new Error("helper type must be either 'instance' or 'static'")
+            }
+
+            // register helper
+            if (type === "instance")
+                this._data.instanceHelpers[name] = helper
+            else if (type === "static")
+                this._data.staticHelpers[name] = helper
+
+            return this;
+        },
+
         /*
          * returns function store based on what has been set
         */