feat: Allow instructors to set rejected courses to draft and explicitly set course status to rejected upon administrative rejection.

Backend/src/controllers/CoursesInstructorController.ts

@@ -21,6 +21,7 @@ import {
     GetQuizAttemptDetailResponse,
     GetEnrolledStudentDetailResponse,
     GetCourseApprovalHistoryResponse,
+    setCourseDraftResponse,
 } from '../types/CoursesInstructor.types';
 import { CreateCourseValidator } from "../validators/CoursesInstructor.validator";
 
@@ -189,6 +190,22 @@ export class CoursesInstructorController {
         return await CoursesInstructorService.sendCourseForReview({ token, course_id: courseId });
     }
 
+    /**
+     * ตั้งค่าคอร์สเป็น DRAFT
+     * Set course to draft
+     * @param courseId - รหัสคอร์ส / Course ID
+     */
+    @Post('set-draft/{courseId}')
+    @Security('jwt', ['instructor'])
+    @SuccessResponse('200', 'Course set to draft successfully')
+    @Response('401', 'Invalid or expired token')
+    @Response('404', 'Course not found')
+    public async setCourseDraft(@Request() request: any, @Path() courseId: number): Promise<setCourseDraftResponse> {
+        const token = request.headers.authorization?.replace('Bearer ', '');
+        if (!token) throw new ValidationError('No token provided')
+        return await CoursesInstructorService.setCourseDraft({ token, course_id: courseId });
+    }
+
     /**
      * ดึงประวัติการส่งอนุมัติคอร์สทั้งหมด
      * Get all course approval history

Backend/src/services/AdminCourseApproval.service.ts

@@ -300,11 +300,11 @@ export class AdminCourseApprovalService {
             }
 
             await prisma.$transaction([
-                // Update course status back to DRAFT
+                // Update course status back to REJECTED
                 prisma.course.update({
                     where: { id: courseId },
                     data: { 
-                        status: 'DRAFT',
+                        status: 'REJECTED',
                         rejection_reason: comment,
                         approved_by: null,
                         approved_at: null
@@ -318,7 +318,7 @@ export class AdminCourseApprovalService {
                         reviewed_by: decoded.id,
                         action: 'REJECTED',
                         previous_status: course.status,
-                        new_status: 'DRAFT',
+                        new_status: 'REJECTED',
                         comment: comment
                     }
                 })
@@ -331,7 +331,7 @@ export class AdminCourseApprovalService {
                 entityType: 'Course',
                 entityId: courseId,
                 oldValue: { status: 'PENDING' },
-                newValue: { status: 'DRAFT' },
+                newValue: { status: 'REJECTED' },
                 metadata: { comment: comment }
             });
 

Backend/src/services/CoursesInstructor.service.ts

@@ -33,6 +33,8 @@ import {
     GetEnrolledStudentDetailInput,
     GetEnrolledStudentDetailResponse,
     GetCourseApprovalHistoryResponse,
+    setCourseDraft,
+    setCourseDraftResponse,
 } from "../types/CoursesInstructor.types";
 import { auditService } from './audit.service';
 import { AuditAction } from '@prisma/client';
@@ -327,6 +329,28 @@ export class CoursesInstructorService {
         }
     }
 
+    static async setCourseDraft(setCourseDraft: setCourseDraft): Promise<setCourseDraftResponse> {
+        try {
+            await this.validateCourseInstructor(setCourseDraft.token, setCourseDraft.course_id);
+            await prisma.course.update({
+                where: {
+                    id: setCourseDraft.course_id,
+                    status: 'REJECTED'
+                },
+                data: {
+                    status: 'DRAFT'
+                }
+            });
+            return {
+                code: 200,
+                message: 'Set course to draft successfully',
+            };
+        } catch (error) {
+            logger.error('Failed to set course to draft', { error });
+            throw error;
+        }
+    }
+
     static async getCourseApprovals(token: string, courseId: number): Promise<{
         code: number;
         message: string;

Backend/src/types/CoursesInstructor.types.ts

@@ -171,6 +171,16 @@ export interface sendCourseForReview {
     course_id: number;
 }
 
+export interface setCourseDraft {
+    token: string;
+    course_id: number;
+}
+
+export interface setCourseDraftResponse {
+    code: number;
+    message: string;
+}
+
 export interface CourseApprovalData {
     id: number;
     course_id: number;