From 33624c89de27a6d730008913ffa689958f5610e3 Mon Sep 17 00:00:00 2001
From: Palash Bansal <palashbansal96@gmail.com>
Date: Mon, 11 Dec 2023 04:09:22 +0530
Subject: [PATCH] Add value, lastValue in the onChange args, Add option to add
 additional options to config when appending in the renderer.

---
 package.json                |  2 +-
 src/UiConfigMethods.ts      | 13 ++++++++-----
 src/UiConfigRendererBase.ts |  3 ++-
 src/types.ts                |  2 ++
 4 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/package.json b/package.json
index 7b64b64..beb357a 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
     "name": "uiconfig.js",
-    "version": "0.0.6",
+    "version": "0.0.7",
     "description": "A framework for building user interface layouts with JSON configuration.",
     "main": "src/index.ts",
     "module": "dist/index.mjs",
diff --git a/src/UiConfigMethods.ts b/src/UiConfigMethods.ts
index 4d2e85f..7fe26b7 100644
--- a/src/UiConfigMethods.ts
+++ b/src/UiConfigMethods.ts
@@ -21,13 +21,15 @@ export class UiConfigMethods {
         return tar ? tar[key] : undefined
     }
 
-    dispatchOnChangeSync(config: UiObjectConfig, props: {last?: boolean, config?: UiObjectConfig, configPath?: UiObjectConfig[]}, ...args: any[]) {
+    dispatchOnChangeSync(config: UiObjectConfig, props: {last?: boolean, config?: UiObjectConfig, configPath?: UiObjectConfig[], value?: any, lastValue?: any}, ...args: any[]) {
         const changeEvent: ChangeEvent = {
             type: 'change',
             last: props.last ?? true,
             config: props.config ?? config,
             configPath: [config, ...props.configPath || []],
             target: config,
+            value: props.value,
+            lastValue: props.lastValue,
         }
         const changeArgs: ChangeArgs = [changeEvent, ...args]
         if (typeof config.onChange === 'function') config.onChange(...changeArgs)
@@ -41,17 +43,18 @@ export class UiConfigMethods {
         config.parentOnChange?.(...changeArgs)
     }
 
-    async setValue<T>(config: UiObjectConfig<T>, value: T, props: {last?: boolean, config?: UiObjectConfig, configPath?: UiObjectConfig[]}, forceOnChange?: boolean) {
+    async setValue<T>(config: UiObjectConfig<T>, value: T, props: {last?: boolean, config?: UiObjectConfig, configPath?: UiObjectConfig[], lastValue?: T}, forceOnChange?: boolean) {
         return this.runAtEvent(config, () => {
             const [tar, key] = this.getBinding(config)
-            if (!tar || value === tar[key] || !safeSetProperty(tar, key, value, true, true)) {
+            const lastValue = props.lastValue ?? tar[key]
+            if (!tar || value === lastValue || !safeSetProperty(tar, key, value, true, true)) {
                 if (!forceOnChange) return false
             }
-            this.dispatchOnChangeSync(config, props)
+            this.dispatchOnChangeSync(config, {...props, value, lastValue})
             return true
         })
     }
-    async dispatchOnChange<T>(config: UiObjectConfig<T>, props: {last?: boolean, config?: UiObjectConfig, configPath?: UiObjectConfig[]}) {
+    async dispatchOnChange<T>(config: UiObjectConfig<T>, props: {last?: boolean, config?: UiObjectConfig, configPath?: UiObjectConfig[], value?: any, lastValue?: any}) {
         return this.runAtEvent(config, () => {
             this.dispatchOnChangeSync(config, props)
         })
diff --git a/src/UiConfigRendererBase.ts b/src/UiConfigRendererBase.ts
index 92551c3..294c6a7 100644
--- a/src/UiConfigRendererBase.ts
+++ b/src/UiConfigRendererBase.ts
@@ -87,8 +87,9 @@ export abstract class UiConfigRendererBase<TUiNode = any> extends SimpleEventDis
     //     this._renderUiConfig(uiConfig)
     // }
 
-    appendChild(config?: UiObjectConfig) {
+    appendChild(config?: UiObjectConfig, params?: UiObjectConfig) {
         if (!config) return
+        Object.assign(config, params)
         this.config.children!.push(config)
         this.refreshRoot()
     }
diff --git a/src/types.ts b/src/types.ts
index 2a39610..f1b1320 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -8,6 +8,8 @@ export interface ChangeEvent {
     last?: boolean, // true if this is the last change event in a chain of changes
     config?: UiObjectConfig, // the config that triggered the change
     configPath?: UiObjectConfig[], // list of all configs from target to the one that triggered the change
+    value?: any, // the new value
+    lastValue?: any, // the old value
 }
 export type ChangeArgs = [ChangeEvent, ...any[]] | never[]