Action Engine

ActionEngine.cs

using Core.Interfaces.Accessors;
using Core.Interfaces.Engines;
using Models;
using System;
using System.Collections.Generic;
using System.Linq;
using Action = Models.Action;

namespace Engines
{
    public class ActionEngine : IActionEngine
    {
        private readonly IActionAccessor actionAccessor;
        private readonly IHistoryAccessor historyAccessor;
        private readonly IUserAccessor userAccessor;

        public ActionEngine(IActionAccessor actionAccessor, IHistoryAccessor historyAccessor, IUserAccessor userAccessor)
        {
            this.actionAccessor = actionAccessor;
            this.historyAccessor = historyAccessor;
            this.userAccessor = userAccessor;
        }

        /// <summary>
        /// Deletes an action and associated history items by ID
        /// </summary>
        /// <param name="id"></param>
        /// <returns></returns>
        public bool DeleteAction(int id)
        {
            // Must get action first in order to know history IDs to delete
            Action action = actionAccessor.GetById(id);

            // Delete both associated history data as well as the action itself
            bool oldHistoryDeleted = historyAccessor.DeleteById((Int32.Parse(action.OldData)));
            bool newHistoryDeleted = historyAccessor.DeleteById((Int32.Parse(action.NewData)));
            bool actionDeleted = actionAccessor.DeleteById(action.Id);

            return oldHistoryDeleted && newHistoryDeleted && actionDeleted;
        }

        /// <summary>
        /// Retrieves all actions and their associated history items
        /// </summary>
        /// <returns></returns>
        public List<Action> GetAllActions()
        {
            List<Action> actions = actionAccessor.GetAllActions();
            List<User> users = userAccessor.GetAllUsers(); 

            // Get history items associated with stored history IDs
            actions.ForEach(action =>
            {
                action.OldData = historyAccessor.GetById(Int32.Parse(action.OldData));
                action.NewData = historyAccessor.GetById(Int32.Parse(action.NewData));
            });

            foreach(Action action in actions)
            {
                string userEmail = users.FirstOrDefault(u => u.Id == action.UserId).Email;
                if (userEmail != null)
                    action.UserEmail = userEmail;
            }

            actions.Reverse();

            return actions;
        }

        /// <summary>
        /// Puts an action and associated history items in resource
        /// </summary>
        /// <param name="action"></param>
        /// <returns></returns>
        public Action PutAction(Action action)
        {
            if (action == null || action.NewData == null || action.OldData == null)
            {
                return null;
            }

            int oldId = historyAccessor.PutHistory(action.OldData);
            int newId = historyAccessor.PutHistory(action.NewData);

            // Set action history data to their resource IDs
            action.OldData = oldId.ToString();
            action.NewData = newId.ToString();

            return actionAccessor.PutAction(action);
        }
    }
}