Refactor Application, add configure() implementation (incomplete)

There is still lots to be done, before the application can be considered complete. The new configure is intended to replace previous "auto" configuration in the setInstance() method.

packages/core/src/Application.ts

@@ -1,6 +1,6 @@
 import {
     Callback,
-    ClassMethodReference
+    ClassMethodReference, type ConstructorLike
 } from "@aedart/contracts";
 import type {
     Application as ApplicationContract,
@@ -10,6 +10,8 @@ import type {
     TerminationCallback,
     DetectEnvironmentCallback,
     DestroyCallback,
+    Configurator,
+    ConfiguratorConstructor
 } from "@aedart/contracts/core";
 import { CallbackWrapper } from "@aedart/contracts/support";
 import { Container } from "@aedart/container";
@@ -28,9 +30,16 @@ import {
     BootError
 } from "@aedart/support/services";
 import { isset } from "@aedart/support/misc";
-import { isPromise } from "@aedart/support/reflections";
+import {
+    getNameOrDesc,
+    isPromise
+} from "@aedart/support/reflections";
+import { isConfigurator } from "./configuration/isConfigurator";
+import { isConfiguratorConstructor } from "./configuration/isConfiguratorConstructor";
+import ConfigurationError from "./exceptions/ConfigurationError";
 import LoadEnvironmentVariables from "./bootstrap/LoadEnvironmentVariables";
 import SetupFacades from "./bootstrap/SetupFacades";
+import DefaultConfigurator from './DefaultConfigurator';
 import { version } from "../package.json";
 
 /**
@@ -106,6 +115,8 @@ export default class Application extends Container implements ApplicationContrac
     protected destroyCallbacks: DestroyCallback[] = [];
 
     /**
+     * @deprecated TODO: Refactor this
+     * 
      * The "core" application bootstrappers to be used when no other
      * bootstrappers are specified.
      * 
@@ -141,6 +152,7 @@ export default class Application extends Container implements ApplicationContrac
         // To avoid such kind of issues, only this singleton instance is configured to have core
         // bootstrappers, base bindings, core service providers, etc.
 
+        // TODO: Refactor this
         if (application !== null) {
             this.configureInstance(application);
         }
@@ -149,6 +161,8 @@ export default class Application extends Container implements ApplicationContrac
     }
 
     /**
+     * @deprecated TODO: Refactor this
+     * 
      * Configure the singleton instance of the given application
      * 
      * @param {ApplicationContract} app
@@ -163,6 +177,25 @@ export default class Application extends Container implements ApplicationContrac
             .setupCoreBootstrappers();
     }
 
+    /**
+     * Configure this application using given configurator
+     *
+     * @param {Configurator | ConfiguratorConstructor} [configurator] If no configurator is given, then
+     *                                                  a default configurator is applied.
+     *
+     * @return {this}
+     *
+     * @throws {ConfigurationException}
+     */
+    public configure(configurator?: Configurator | ConfiguratorConstructor): this
+    {
+        configurator = this.resolveConfigurator(configurator || this.makeDefaultConfigurator());
+
+        return configurator
+            .for(this)
+            .apply() as this;
+    }
+
     /**
      * This core application's current version
      *
@@ -267,9 +300,11 @@ export default class Application extends Container implements ApplicationContrac
     }
 
     /**
+     * @deprecated TODO: Refactor this
+     * 
      * This "core" application's default bootstrappers
      */
-    public get coreBootstrappers(): BootstrapperConstructor[]
+    public get _coreBootstrappers(): BootstrapperConstructor[]
     {
         // Core bootstrappers are only set automatically for the singleton
         // instance of this application.
@@ -443,7 +478,7 @@ export default class Application extends Container implements ApplicationContrac
 
         // Bootstrap the application, using the "default" bootstrappers. NOTE: If the
         // application has already been bootstrapped, then this call will do nothing.
-        this.bootstrapWith(this.coreBootstrappers);
+        this.bootstrapWith(this._coreBootstrappers);
 
         // Boot, if not already booted.
         await this.boot();
@@ -578,6 +613,8 @@ export default class Application extends Container implements ApplicationContrac
     }
 
     /**
+     * @deprecated TODO: Refactor this
+     * 
      * Register the "base" bindings for this application
      *
      * @returns {ApplicationContract | this}
@@ -593,6 +630,8 @@ export default class Application extends Container implements ApplicationContrac
     }
 
     /**
+     * @deprecated TODO: Refactor this
+     * 
      * Set the default "core" bootstrappers
      *
      * @returns {ApplicationContract | this}
@@ -664,4 +703,41 @@ export default class Application extends Container implements ApplicationContrac
     {
         return new ServiceRegistrar(this);
     }
+
+    /**
+     * Returns a new "default" application configurator instance
+     * 
+     * @return {Configurator}
+     * 
+     * @protected
+     */
+    protected makeDefaultConfigurator(): Configurator
+    {
+        return new DefaultConfigurator(this);
+    }
+
+    /**
+     * Resolves Application Configurator
+     *
+     * @param {Configurator | ConfiguratorConstructor} configurator
+     *
+     * @return {Configurator}
+     *
+     * @throws {ConfigurationException}
+     *
+     * @protected
+     */
+    protected resolveConfigurator(configurator: Configurator | ConfiguratorConstructor): Configurator
+    {
+        if (isConfigurator(configurator)) {
+            return configurator as Configurator;
+        }
+
+        if (isConfiguratorConstructor(configurator)) {
+            return new (configurator as ConfiguratorConstructor)();
+        }
+
+        const msg = `Unable to resolve application configurator: ${getNameOrDesc(configurator as ConstructorLike)} is not a valid configurator`;
+        throw new ConfigurationError(msg, { cause: { configurator: configurator } })
+    }
 }