Merge pull request #18 from Team-Kaleidoscope/devv0.1

First stage: Complete. Awaiting further progress...

1 files changed, 169 insertions, 0 deletions

diff --git a/src/DevHive.Services/Services/CommentService.cs b/src/DevHive.Services/Services/CommentService.cs
new file mode 100644
index 0000000..e2b54c4
--- /dev/null
+++ b/src/DevHive.Services/Services/CommentService.cs
@@ -0,0 +1,169 @@
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using AutoMapper;
+using DevHive.Data.Models;
+using DevHive.Services.Models.Comment;
+using System.IdentityModel.Tokens.Jwt;
+using System.Security.Claims;
+using DevHive.Services.Interfaces;
+using DevHive.Data.Interfaces.Repositories;
+using System.Linq;
+
+namespace DevHive.Services.Services
+{
+	public class CommentService : ICommentService
+	{
+		private readonly IUserRepository _userRepository;
+		private readonly IPostRepository _postRepository;
+		private readonly ICommentRepository _commentRepository;
+		private readonly IMapper _postMapper;
+
+		public CommentService(IUserRepository userRepository, IPostRepository postRepository, ICommentRepository commentRepository, IMapper postMapper)
+		{
+			this._userRepository = userRepository;
+			this._postRepository = postRepository;
+			this._commentRepository = commentRepository;
+			this._postMapper = postMapper;
+		}
+
+		#region Create
+		public async Task<Guid> AddComment(CreateCommentServiceModel createCommentServiceModel)
+		{
+			if (!await this._postRepository.DoesPostExist(createCommentServiceModel.PostId))
+				throw new ArgumentException("Post does not exist!");
+
+			Comment comment = this._postMapper.Map<Comment>(createCommentServiceModel);
+			comment.TimeCreated = DateTime.Now;
+
+			comment.Creator = await this._userRepository.GetByIdAsync(createCommentServiceModel.CreatorId);
+			comment.Post = await this._postRepository.GetByIdAsync(createCommentServiceModel.PostId);
+
+			bool success = await this._commentRepository.AddAsync(comment);
+			if (success)
+			{
+				Comment newComment = await this._commentRepository
+					.GetCommentByIssuerAndTimeCreatedAsync(comment.Creator.Id, comment.TimeCreated);
+
+				return newComment.Id;
+			}
+			else
+				return Guid.Empty;
+		}
+		#endregion
+
+		#region Read
+		public async Task<ReadCommentServiceModel> GetCommentById(Guid id)
+		{
+			Comment comment = await this._commentRepository.GetByIdAsync(id) ??
+				throw new ArgumentException("The comment does not exist");
+
+			User user = await this._userRepository.GetByIdAsync(comment.Creator.Id) ??
+				throw new ArgumentException("The user does not exist");
+
+			ReadCommentServiceModel readCommentServiceModel = this._postMapper.Map<ReadCommentServiceModel>(comment);
+			readCommentServiceModel.IssuerFirstName = user.FirstName;
+			readCommentServiceModel.IssuerLastName = user.LastName;
+			readCommentServiceModel.IssuerUsername = user.UserName;
+
+			return readCommentServiceModel;
+		}
+		#endregion
+
+		#region Update
+		public async Task<Guid> UpdateComment(UpdateCommentServiceModel updateCommentServiceModel)
+		{
+			if (!await this._commentRepository.DoesCommentExist(updateCommentServiceModel.CommentId))
+				throw new ArgumentException("Comment does not exist!");
+
+			Comment comment = this._postMapper.Map<Comment>(updateCommentServiceModel);
+			comment.TimeCreated = DateTime.Now;
+
+			comment.Creator = await this._userRepository.GetByIdAsync(updateCommentServiceModel.CreatorId);
+			comment.Post = await this._postRepository.GetByIdAsync(updateCommentServiceModel.PostId);
+
+			bool result = await this._commentRepository.EditAsync(updateCommentServiceModel.CommentId, comment);
+
+			if (result)
+				return (await this._commentRepository.GetByIdAsync(updateCommentServiceModel.CommentId)).Id;
+			else
+				return Guid.Empty;
+		}
+		#endregion
+
+		#region Delete
+		public async Task<bool> DeleteComment(Guid id)
+		{
+			if (!await this._commentRepository.DoesCommentExist(id))
+				throw new ArgumentException("Comment does not exist!");
+
+			Comment comment = await this._commentRepository.GetByIdAsync(id);
+			return await this._commentRepository.DeleteAsync(comment);
+		}
+		#endregion
+
+		#region Validations
+		/// <summary>
+		/// Checks whether the user Id in the token and the given user Id match
+		/// </summary>
+		public async Task<bool> ValidateJwtForCreating(Guid userId, string rawTokenData)
+		{
+			User user = await this.GetUserForValidation(rawTokenData);
+
+			return user.Id == userId;
+		}
+
+		/// <summary>
+		/// Checks whether the comment, gotten with the commentId,
+		/// is made by the user in the token
+		/// or if the user in the token is an admin
+		/// </summary>
+		public async Task<bool> ValidateJwtForComment(Guid commentId, string rawTokenData)
+		{
+			Comment comment = await this._commentRepository.GetByIdAsync(commentId) ??
+				throw new ArgumentException("Comment does not exist!");
+			User user = await this.GetUserForValidation(rawTokenData);
+
+			//If user made the comment
+			if (comment.Creator.Id == user.Id)
+				return true;
+			//If user is admin
+			else if (user.Roles.Any(x => x.Name == Role.AdminRole))
+				return true;
+			else
+				return false;
+		}
+
+		/// <summary>
+		/// Returns the user, via their Id in the token
+		/// </summary>
+		private async Task<User> GetUserForValidation(string rawTokenData)
+		{
+			JwtSecurityToken jwt = new JwtSecurityTokenHandler().ReadJwtToken(rawTokenData.Remove(0, 7));
+
+			Guid jwtUserId = Guid.Parse(this.GetClaimTypeValues("ID", jwt.Claims).First());
+			//HashSet<string> jwtRoleNames = this.GetClaimTypeValues("role", jwt.Claims);
+
+			User user = await this._userRepository.GetByIdAsync(jwtUserId) ??
+				throw new ArgumentException("User does not exist!");
+
+			return user;
+		}
+
+		/// <summary>
+		/// Returns all values from a given claim type
+		/// </summary>
+		private List<string> GetClaimTypeValues(string type, IEnumerable<Claim> claims)
+		{
+			List<string> toReturn = new();
+
+			foreach (var claim in claims)
+				if (claim.Type == type)
+					toReturn.Add(claim.Value);
+
+			return toReturn;
+		}
+		#endregion
+	}
+}
+