From 014c20b4f4f2f1d3dbb2b0f8a3c2927672b5dd84 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Adina=20=C8=9Aeudan?= <adina@devplant.ro>
Date: Sat, 2 Oct 2021 23:38:08 +0300
Subject: [PATCH] Custom route reuse strategy

---
 src/lib/utils/custom-route-reuse.strategy.ts | 86 ++++++++++++++++++++
 src/lib/utils/index.ts                       |  1 +
 2 files changed, 87 insertions(+)
 create mode 100644 src/lib/utils/custom-route-reuse.strategy.ts

diff --git a/src/lib/utils/custom-route-reuse.strategy.ts b/src/lib/utils/custom-route-reuse.strategy.ts
new file mode 100644
index 0000000..2cc8956
--- /dev/null
+++ b/src/lib/utils/custom-route-reuse.strategy.ts
@@ -0,0 +1,86 @@
+import { ActivatedRouteSnapshot, DetachedRouteHandle, RouteReuseStrategy } from '@angular/router';
+import { Debounce } from '../utils';
+
+export interface OnAttach {
+    ngOnAttach(previousRoute?: ActivatedRouteSnapshot): void;
+}
+
+export interface OnDetach {
+    ngOnDetach(): void;
+}
+
+interface RouteStorageObject {
+    handle: DetachedRouteHandle;
+    previousRoute: ActivatedRouteSnapshot;
+}
+
+export class CustomRouteReuseStrategy implements RouteReuseStrategy {
+    private _storedRoutes: { [key: string]: RouteStorageObject } = {};
+
+    private static _removeTooltips(): void {
+        while (document.getElementsByTagName('mat-tooltip-component').length > 0) {
+            document.getElementsByTagName('mat-tooltip-component')[0].remove();
+        }
+    }
+
+    shouldDetach(route: ActivatedRouteSnapshot): boolean {
+        if (!route?.routeConfig?.data) {
+            return false;
+        }
+        return !!route.routeConfig.data.reuse && !!this._getKey(route);
+    }
+
+    store(route: ActivatedRouteSnapshot, handle: DetachedRouteHandle): void {
+        if (handle === null) {
+            return;
+        }
+        CustomRouteReuseStrategy._removeTooltips();
+
+        const element: any = handle;
+
+        if (element?.componentRef?.instance?.ngOnDetach) {
+            this._onDetach(element.componentRef?.instance);
+        }
+
+        this._storedRoutes[this._getKey(route)] = {
+            handle: element as DetachedRouteHandle,
+            previousRoute: route
+        };
+    }
+
+    shouldAttach(route: ActivatedRouteSnapshot): boolean {
+        return !!this._storedRoutes[this._getKey(route)];
+    }
+
+    retrieve(route: ActivatedRouteSnapshot): DetachedRouteHandle {
+        const key = this._getKey(route);
+        const element: any = this._storedRoutes[key]?.handle;
+
+        if (element?.componentRef?.instance?.ngOnAttach) {
+            this._onAttach(element.componentRef?.instance, this._storedRoutes[key].previousRoute);
+        }
+
+        return element as DetachedRouteHandle;
+    }
+
+    shouldReuseRoute(future: ActivatedRouteSnapshot, current: ActivatedRouteSnapshot): boolean {
+        return future.routeConfig === current.routeConfig || this._getKey(future) === this._getKey(current);
+    }
+
+    private _getKey(route: ActivatedRouteSnapshot): string {
+        return route.pathFromRoot
+            .map((el: ActivatedRouteSnapshot) => (el.routeConfig ? (el.routeConfig.path as string) + JSON.stringify(el.params) : ''))
+            .filter(str => str.length > 0)
+            .join('');
+    }
+
+    @Debounce()
+    private _onAttach(instance: OnAttach, previousRoute?: ActivatedRouteSnapshot) {
+        instance.ngOnAttach(previousRoute);
+    }
+
+    @Debounce()
+    private _onDetach(instance: OnDetach) {
+        instance.ngOnDetach();
+    }
+}
diff --git a/src/lib/utils/index.ts b/src/lib/utils/index.ts
index 1b27d07..039abbc 100644
--- a/src/lib/utils/index.ts
+++ b/src/lib/utils/index.ts
@@ -13,3 +13,4 @@ export * from './decorators/on-change.decorator';
 export * from './http-encoder';
 export * from './types/iqser-types';
 export * from './pruning-translation-loader';
+export * from './custom-route-reuse.strategy';