コード例 #1
0
        /*
         * Given a new post, match it with the most appropriate post (if possible).
         *
         * Conditions
         * ----------
         *
         * If the new post was made by a buyer, then the matching post must have:
         *      -price less than or equal to that specified by buyer
         *      -book condition better than or equal to that specified by buyer
         *
         * If the new post was made by a seller, then the matching post must have:
         *      -price greater than or equal to that specified by seller
         *      -book condition worse than or equal to that specified by seller
         *
         */
        public static void Match(Post newPost)
        {
            if (!PostHandler.isPostAvailable(newPost.PostId))
            {
                return;
            }

            Post matchingPost = PostHandler.findMatchingPost(newPost);

            if (matchingPost != null)
            {
                int buyerPostId  = -1;
                int sellerPostId = -1;

                int buyerUserId  = -1;
                int sellerUserId = -1;

                int initialPrice;

                if (newPost.ActionBy == ActionBy.Buyer)
                {
                    buyerPostId  = newPost.PostId;
                    sellerPostId = matchingPost.PostId;

                    buyerUserId  = newPost.UserId;
                    sellerUserId = matchingPost.UserId;

                    initialPrice = matchingPost.Price;
                }
                else
                {
                    buyerPostId  = matchingPost.PostId;
                    sellerPostId = newPost.PostId;

                    buyerUserId  = matchingPost.UserId;
                    sellerUserId = newPost.UserId;

                    initialPrice = newPost.Price;
                }

                // Create transaction and transactionhistory for the matched buyer & seller
                Transaction newTransaction = new Transaction(
                    -1, // id doesnt matter here
                    newPost.TextBookId,
                    sellerUserId,
                    buyerUserId,
                    sellerPostId,
                    buyerPostId,
                    null,
                    null,
                    initialPrice,
                    0,
                    1,
                    0,
                    DateTime.Now,
                    DateTime.Now
                    );

                PostHandler.updatePostState(newPost.PostId, 1);
                PostHandler.updatePostState(matchingPost.PostId, 1);

                int transactionId = TransactionHandler.CreateTransaction(newTransaction);
                newTransaction.TransactionId = transactionId;

                TransactionHandler.CreateTransactionHistory(transactionId, buyerUserId);
                TransactionHandler.CreateTransactionHistory(transactionId, sellerUserId);
            }
        }