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

First stage: Complete. Awaiting further progress...

1 files changed, 239 insertions, 0 deletions

diff --git a/src/DevHive.Services/Services/PostService.cs b/src/DevHive.Services/Services/PostService.cs
new file mode 100644
index 0000000..fe91f23
--- /dev/null
+++ b/src/DevHive.Services/Services/PostService.cs
@@ -0,0 +1,239 @@
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using AutoMapper;
+using DevHive.Data.Models;
+using DevHive.Services.Models.Post;
+using System.IdentityModel.Tokens.Jwt;
+using System.Security.Claims;
+using DevHive.Services.Interfaces;
+using DevHive.Data.Interfaces.Repositories;
+using System.Linq;
+using DevHive.Data.RelationModels;
+
+namespace DevHive.Services.Services
+{
+    public class PostService : IPostService
+	{
+		private readonly ICloudService _cloudService;
+		private readonly IUserRepository _userRepository;
+		private readonly IPostRepository _postRepository;
+		private readonly ICommentRepository _commentRepository;
+		private readonly IMapper _postMapper;
+
+		public PostService(ICloudService cloudService, IUserRepository userRepository, IPostRepository postRepository, ICommentRepository commentRepository, IMapper postMapper)
+		{
+			this._cloudService = cloudService;
+			this._userRepository = userRepository;
+			this._postRepository = postRepository;
+			this._commentRepository = commentRepository;
+			this._postMapper = postMapper;
+		}
+
+		#region Create
+		public async Task<Guid> CreatePost(CreatePostServiceModel createPostServiceModel)
+		{
+			if (!await this._userRepository.DoesUserExistAsync(createPostServiceModel.CreatorId))
+				throw new ArgumentException("User does not exist!");
+
+			Post post = this._postMapper.Map<Post>(createPostServiceModel);
+
+			if (createPostServiceModel.Files.Count != 0)
+			{
+				List<string> fileUrls = await _cloudService.UploadFilesToCloud(createPostServiceModel.Files);
+				post.Attachments = this.GetPostAttachmentsFromUrls(post, fileUrls);
+			}
+
+			post.Creator = await this._userRepository.GetByIdAsync(createPostServiceModel.CreatorId);
+			post.TimeCreated = DateTime.Now;
+
+			bool success = await this._postRepository.AddAsync(post);
+			if (success)
+			{
+				Post newPost = await this._postRepository
+					.GetPostByCreatorAndTimeCreatedAsync(post.Creator.Id, post.TimeCreated);
+
+				await this._postRepository.AddNewPostToCreator(createPostServiceModel.CreatorId, newPost);
+
+				return newPost.Id;
+			}
+			else
+				return Guid.Empty;
+		}
+		#endregion
+
+		#region Read
+		public async Task<ReadPostServiceModel> GetPostById(Guid id)
+		{
+			Post post = await this._postRepository.GetByIdAsync(id) ??
+				throw new ArgumentException("The post does not exist!");
+
+			// This can't happen in repo, because of how time is usually compared
+			post.Comments = post.Comments
+				.OrderByDescending(x => x.TimeCreated.ToFileTimeUtc())
+				.ToList();
+
+			User user = await this._userRepository.GetByIdAsync(post.Creator.Id) ??
+				throw new ArgumentException("The user does not exist!");
+
+			ReadPostServiceModel readPostServiceModel = this._postMapper.Map<ReadPostServiceModel>(post);
+			readPostServiceModel.CreatorFirstName = user.FirstName;
+			readPostServiceModel.CreatorLastName = user.LastName;
+			readPostServiceModel.CreatorUsername = user.UserName;
+			readPostServiceModel.FileUrls = post.Attachments.Select(x => x.FileUrl).ToList();
+
+			return readPostServiceModel;
+		}
+		#endregion
+
+		#region Update
+		public async Task<Guid> UpdatePost(UpdatePostServiceModel updatePostServiceModel)
+		{
+			if (!await this._postRepository.DoesPostExist(updatePostServiceModel.PostId))
+				throw new ArgumentException("Post does not exist!");
+
+			Post post = this._postMapper.Map<Post>(updatePostServiceModel);
+
+			if (updatePostServiceModel.Files.Count != 0)
+			{
+				if (await this._postRepository.DoesPostHaveFiles(updatePostServiceModel.PostId))
+				{
+					List<string> fileUrlsToRemove = await this._postRepository.GetFileUrls(updatePostServiceModel.PostId);
+					bool success = await _cloudService.RemoveFilesFromCloud(fileUrlsToRemove);
+					if (!success)
+						throw new InvalidCastException("Could not delete files from the post!");
+				}
+
+				List<string> fileUrls = await _cloudService.UploadFilesToCloud(updatePostServiceModel.Files) ??
+					throw new ArgumentNullException("Unable to upload images to cloud");
+				post.Attachments = this.GetPostAttachmentsFromUrls(post, fileUrls);
+			}
+
+			post.Creator = await this._userRepository.GetByIdAsync(updatePostServiceModel.CreatorId);
+			post.Comments = await this._commentRepository.GetPostComments(updatePostServiceModel.PostId);
+			post.TimeCreated = DateTime.Now;
+
+			bool result = await this._postRepository.EditAsync(updatePostServiceModel.PostId, post);
+
+			if (result)
+				return (await this._postRepository.GetByIdAsync(updatePostServiceModel.PostId)).Id;
+			else
+				return Guid.Empty;
+		}
+		#endregion
+
+		#region Delete
+		public async Task<bool> DeletePost(Guid id)
+		{
+			if (!await this._postRepository.DoesPostExist(id))
+				throw new ArgumentException("Post does not exist!");
+
+			Post post = await this._postRepository.GetByIdAsync(id);
+
+			if (await this._postRepository.DoesPostHaveFiles(id))
+			{
+				List<string> fileUrls = await this._postRepository.GetFileUrls(id);
+				bool success = await _cloudService.RemoveFilesFromCloud(fileUrls);
+				if (!success)
+					throw new InvalidCastException("Could not delete files from the post. Please try again");
+			}
+
+			return await this._postRepository.DeleteAsync(post);
+		}
+		#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 post, gotten with the postId,
+		/// is made by the user in the token
+		/// or if the user in the token is an admin
+        /// </summary>
+		public async Task<bool> ValidateJwtForPost(Guid postId, string rawTokenData)
+		{
+			Post post = await this._postRepository.GetByIdAsync(postId) ??
+				throw new ArgumentException("Post does not exist!");
+			User user = await this.GetUserForValidation(rawTokenData);
+
+			//If user made the post
+			if (post.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>
+        /// 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
+
+		#region Misc
+		private List<PostAttachments> GetPostAttachmentsFromUrls(Post post, List<string> fileUrls)
+		{
+			List<PostAttachments> postAttachments = new List<PostAttachments>();
+			foreach (string url in fileUrls)
+				postAttachments.Add(new PostAttachments { Post = post, FileUrl = url });
+			return postAttachments;
+		}
+		#endregion
+	}
+}