View all comment for a particular discussion

BLL/Interfaces/Discussion.cs

@@ -12,6 +12,7 @@ public interface IDiscussionService
         Task<GetDiscussionDTO> AddNewDiscussionAsync(CreateDiscussionDTO Discussion);
         Task DeleteAsync(int id);
         Task<GetDiscussionDTO> GetByIdAsync(int id);
+        Task<List<GetCommentDTO>> GetListCommentByIdDiscussionAsync(int id);
         Task<List<GetDiscussionDTO>> GetAllDiscussionsAsync();
         Task<GetDiscussionDTO> UpdateAsync(CreateDiscussionDTO Discussion);
     }

BLL/Services/Discussion.cs

@@ -86,6 +86,12 @@ public async Task<GetDiscussionDTO> GetByIdAsync(int id)
             }
         }
 
+        public async Task<List<GetCommentDTO>> GetListCommentByIdDiscussionAsync(int id)
+        {
+           var answer = await DiscussionRepository.GetListCommentByIdDiscussionAsync(id);
+            return mapper.Map<List<GetCommentDTO>>(answer);
+        }
+
         public async Task<GetDiscussionDTO> UpdateAsync(CreateDiscussionDTO e)
         {
             try

DAL/Interfaces/Discussion.cs

@@ -10,6 +10,7 @@ namespace DAL.Interfaces
     public interface IDiscussionRepository
     {
         Task<List<Discussion>> GetAllAsync();
+        Task<List<Comment>> GetListCommentByIdDiscussionAsync(int id);
         Task<Discussion> GetByIdAsync(int id);
         Task<Discussion> UpdateAsync(Discussion entity);
         Task<Discussion> AddAsync(Discussion entity);

DAL/Repositories/Discussion.cs

@@ -94,6 +94,33 @@ public async Task<Discussion> GetByIdAsync(int Id)
                 throw;
             }
         }
+        public async Task<List<Comment>> GetListCommentByIdDiscussionAsync(int Id)
+        {
+            try
+            {
+                var discussion = await GetByIdAsync(Id);
+                if (discussion == null)
+                {
+                    throw new ArgumentNullException(nameof(discussion), "The Id Discussion is null");
+                }
+                else
+                {
+                    List<Comment> comments = new List<Comment>();
+                    foreach (var item in discussion.Comments)
+                    {
+
+                        if (item.DiscussionId == Id)
+                            comments.Add(item);
+                    }
+                    return discussion.Comments.Where(item => item.DiscussionId == Id).ToList();
+                }
+            }
+            catch (Exception ex)
+            {
+                logger.LogError("failed to get Comment To Discussion" + ex.Message.ToString());
+                throw;
+            }
+        }
 
         public async Task<Discussion> UpdateAsync(Discussion entity)
         {

WebApi/Controllers/DiscussionController.cs

@@ -65,6 +65,29 @@ public async Task<IActionResult> GetById(int id)
                 return StatusCode(500, "Internal Server Error"); // HTTP 500
             }
         }
+        [HttpGet("GetListComment/{id}")]
+        public async Task<IActionResult> GetListCommentById(int id)
+        {
+            try
+            {
+                var comment = await DiscussionService.GetListCommentByIdDiscussionAsync(id);
+                if (comment == null)
+                {
+                    return NotFound($"Discussion with ID {id} not found"); // HTTP 404
+                }
+                return Ok(comment); // HTTP 200 OK
+            }
+            catch (ArgumentException ex)
+            {
+                logger.LogError($"Invalid argument: {ex.Message}");
+                return BadRequest(ex.Message); // HTTP 400
+            }
+            catch (Exception ex)
+            {
+                logger.LogError($"Failed to get discussion with ID {id}: {ex.Message}");
+                return StatusCode(500, "Internal Server Error"); // HTTP 500
+            }
+        }
 
         [HttpPost]
         public async Task<IActionResult> Add([FromBody] CreateDiscussionDTO newDiscussion)