From fa3a7f52584727ca856786defdd078c585bf76cb Mon Sep 17 00:00:00 2001
From: Aleksandr Bukhalo <aleksandr@bukhalo.com>
Date: Thu, 19 Mar 2020 16:44:05 +0300
Subject: [PATCH] feat(decorators): TelegrafHelp added

---
 lib/decorators/index.ts                   |  1 +
 lib/decorators/telegraf-help.decorator.ts | 11 +++++++++
 lib/telegraf-metadata.accessor.ts         | 21 ++++++++++------
 lib/telegraf.constants.ts                 |  1 +
 lib/telegraf.explorer.ts                  | 30 +++++++++++++++--------
 5 files changed, 47 insertions(+), 17 deletions(-)
 create mode 100644 lib/decorators/telegraf-help.decorator.ts

diff --git a/lib/decorators/index.ts b/lib/decorators/index.ts
index c94e0a3..63c6636 100644
--- a/lib/decorators/index.ts
+++ b/lib/decorators/index.ts
@@ -3,3 +3,4 @@ export * from './telegraf-on.decorator';
 export * from './telegraf-hears.decorator';
 export * from './telegraf-command.decorator';
 export * from './telegraf-start.decorator';
+export * from './telegraf-help.decorator';
diff --git a/lib/decorators/telegraf-help.decorator.ts b/lib/decorators/telegraf-help.decorator.ts
new file mode 100644
index 0000000..7bade62
--- /dev/null
+++ b/lib/decorators/telegraf-help.decorator.ts
@@ -0,0 +1,11 @@
+import { SetMetadata } from '@nestjs/common';
+import { DECORATORS } from '../telegraf.constants';
+
+/**
+ * Handler for /help command.
+ *
+ * https://telegraf.js.org/#/?id=help
+ */
+export function TelegrafHelp(): MethodDecorator {
+  return SetMetadata(DECORATORS.HELP, {});
+}
diff --git a/lib/telegraf-metadata.accessor.ts b/lib/telegraf-metadata.accessor.ts
index d419ece..30ce062 100644
--- a/lib/telegraf-metadata.accessor.ts
+++ b/lib/telegraf-metadata.accessor.ts
@@ -14,13 +14,6 @@ export class TelegrafMetadataAccessor {
     return !!this.reflector.get(DECORATORS.USE, target);
   }
 
-  isTelegrafStart(target: Type<any> | Function): boolean {
-    if (!target) {
-      return false;
-    }
-    return !!this.reflector.get(DECORATORS.START, target);
-  }
-
   isTelegrafOn(target: Type<any> | Function): boolean {
     if (!target) {
       return false;
@@ -53,4 +46,18 @@ export class TelegrafMetadataAccessor {
   getTelegrafCommandMetadata(target: Type<any> | Function) {
     return this.reflector.get(DECORATORS.COMMAND, target);
   }
+
+  isTelegrafStart(target: Type<any> | Function): boolean {
+    if (!target) {
+      return false;
+    }
+    return !!this.reflector.get(DECORATORS.START, target);
+  }
+
+  isTelegrafHelp(target: Type<any> | Function): boolean {
+    if (!target) {
+      return false;
+    }
+    return !!this.reflector.get(DECORATORS.HELP, target);
+  }
 }
diff --git a/lib/telegraf.constants.ts b/lib/telegraf.constants.ts
index 114821e..78ee19a 100644
--- a/lib/telegraf.constants.ts
+++ b/lib/telegraf.constants.ts
@@ -8,4 +8,5 @@ export const DECORATORS = {
   HEARS: `${DECORATORS_PREFIX}/HEARS`,
   COMMAND: `${DECORATORS_PREFIX}/COMMAND`,
   START: `${DECORATORS_PREFIX}/START`,
+  HELP: `${DECORATORS_PREFIX}/HELP`,
 };
diff --git a/lib/telegraf.explorer.ts b/lib/telegraf.explorer.ts
index c2f12cc..2187ffd 100644
--- a/lib/telegraf.explorer.ts
+++ b/lib/telegraf.explorer.ts
@@ -41,8 +41,6 @@ export class TelegrafExplorer implements OnModuleInit {
         (key: string) => {
           if (this.metadataAccessor.isTelegrafUse(instance[key])) {
             this.handleTelegrafUse(instance, key, telegraf);
-          } else if (this.metadataAccessor.isTelegrafStart(instance[key])) {
-            this.handleTelegrafStart(instance, key, telegraf);
           } else if (this.metadataAccessor.isTelegrafOn(instance[key])) {
             const metadata = this.metadataAccessor.getTelegrafOnMetadata(
               instance[key],
@@ -58,6 +56,10 @@ export class TelegrafExplorer implements OnModuleInit {
               instance[key],
             );
             this.handleTelegrafCommand(instance, key, telegraf, metadata);
+          } else if (this.metadataAccessor.isTelegrafStart(instance[key])) {
+            this.handleTelegrafStart(instance, key, telegraf);
+          } else if (this.metadataAccessor.isTelegrafHelp(instance[key])) {
+            this.handleTelegrafHelp(instance, key, telegraf);
           }
         },
       );
@@ -81,14 +83,6 @@ export class TelegrafExplorer implements OnModuleInit {
     telegraf.on(metadata.updateTypes, instance[key].bind(instance));
   }
 
-  handleTelegrafStart(
-    instance: object,
-    key: string,
-    telegraf: Telegraf<ContextMessageUpdate>,
-  ) {
-    telegraf.start(instance[key].bind(instance));
-  }
-
   handleTelegrafHears(
     instance: object,
     key: string,
@@ -106,4 +100,20 @@ export class TelegrafExplorer implements OnModuleInit {
   ) {
     telegraf.command(metadata.commands, instance[key].bind(instance));
   }
+
+  handleTelegrafStart(
+    instance: object,
+    key: string,
+    telegraf: Telegraf<ContextMessageUpdate>,
+  ) {
+    telegraf.start(instance[key].bind(instance));
+  }
+
+  handleTelegrafHelp(
+    instance: object,
+    key: string,
+    telegraf: Telegraf<ContextMessageUpdate>,
+  ) {
+    telegraf.help(instance[key].bind(instance));
+  }
 }