From 8bd20131a10840a391fc52f5aabe7d04d948acf2 Mon Sep 17 00:00:00 2001
From: Aleksandr Bukhalo <aleksandr@bukhalo.com>
Date: Thu, 19 Mar 2020 16:54:34 +0300
Subject: [PATCH] feat(decorators): TelegrafEntity added

---
 lib/decorators/index.ts                     |  1 +
 lib/decorators/telegraf-entity.decorator.ts | 14 ++++++++++++++
 lib/telegraf-metadata.accessor.ts           | 11 +++++++++++
 lib/telegraf.constants.ts                   |  1 +
 lib/telegraf.explorer.ts                    | 15 +++++++++++++++
 5 files changed, 42 insertions(+)
 create mode 100644 lib/decorators/telegraf-entity.decorator.ts

diff --git a/lib/decorators/index.ts b/lib/decorators/index.ts
index 63c6636..dd968ab 100644
--- a/lib/decorators/index.ts
+++ b/lib/decorators/index.ts
@@ -4,3 +4,4 @@ export * from './telegraf-hears.decorator';
 export * from './telegraf-command.decorator';
 export * from './telegraf-start.decorator';
 export * from './telegraf-help.decorator';
+export * from './telegraf-entity.decorator';
diff --git a/lib/decorators/telegraf-entity.decorator.ts b/lib/decorators/telegraf-entity.decorator.ts
new file mode 100644
index 0000000..cf1173d
--- /dev/null
+++ b/lib/decorators/telegraf-entity.decorator.ts
@@ -0,0 +1,14 @@
+import { SetMetadata } from '@nestjs/common';
+import { DECORATORS } from '../telegraf.constants';
+
+export type Entity = string | string[] | RegExp | RegExp[] | Function;
+
+/**
+ * Entity handling.
+ * @param entity Entity name
+ *
+ * https://telegraf.js.org/#/?id=entity
+ */
+export function TelegrafEntity(entity: Entity): MethodDecorator {
+  return SetMetadata(DECORATORS.ENTITY, { entity });
+}
diff --git a/lib/telegraf-metadata.accessor.ts b/lib/telegraf-metadata.accessor.ts
index 7895bce..34c5f06 100644
--- a/lib/telegraf-metadata.accessor.ts
+++ b/lib/telegraf-metadata.accessor.ts
@@ -67,4 +67,15 @@ export class TelegrafMetadataAccessor {
     }
     return !!this.reflector.get(DECORATORS.SETTINGS, target);
   }
+
+  isTelegrafEntity(target: Type<any> | Function): boolean {
+    if (!target) {
+      return false;
+    }
+    return !!this.reflector.get(DECORATORS.ENTITY, target);
+  }
+
+  getTelegrafEntityMetadata(target: Type<any> | Function) {
+    return this.reflector.get(DECORATORS.ENTITY, target);
+  }
 }
diff --git a/lib/telegraf.constants.ts b/lib/telegraf.constants.ts
index e48a9a8..fa18e0a 100644
--- a/lib/telegraf.constants.ts
+++ b/lib/telegraf.constants.ts
@@ -10,4 +10,5 @@ export const DECORATORS = {
   START: `${DECORATORS_PREFIX}/START`,
   HELP: `${DECORATORS_PREFIX}/HELP`,
   SETTINGS: `${DECORATORS_PREFIX}/SETTINGS`,
+  ENTITY: `${DECORATORS_PREFIX}/ENTITY`,
 };
diff --git a/lib/telegraf.explorer.ts b/lib/telegraf.explorer.ts
index 1528843..2665b28 100644
--- a/lib/telegraf.explorer.ts
+++ b/lib/telegraf.explorer.ts
@@ -62,6 +62,11 @@ export class TelegrafExplorer implements OnModuleInit {
             this.handleTelegrafHelp(instance, key, telegraf);
           } else if (this.metadataAccessor.isTelegrafSettings(instance[key])) {
             this.handleTelegrafSettings(instance, key, telegraf);
+          } else if (this.metadataAccessor.isTelegrafEntity(instance[key])) {
+            const metadata = this.metadataAccessor.getTelegrafEntityMetadata(
+              instance[key],
+            );
+            this.handleTelegrafEntity(instance, key, telegraf, metadata);
           }
         },
       );
@@ -127,4 +132,14 @@ export class TelegrafExplorer implements OnModuleInit {
     // @ts-ignore
     telegraf.settings(instance[key].bind(instance));
   }
+
+  handleTelegrafEntity(
+    instance: object,
+    key: string,
+    telegraf: Telegraf<ContextMessageUpdate>,
+    metadata: any,
+  ) {
+    // @ts-ignore
+    telegraf.entity(metadata.entity, instance[key].bind(instance));
+  }
 }