using System;
using System.Collections.Generic;
using System.Diagnostics;

using Microsoft.Xrm.Sdk;

namespace XrmTools
{
    public class XrmTools
    {
        public static List<EntityLink> References { get; set; }

        private static string[] entityNames = null;
        public static string[] EntityNames
        {
            get
            {
                if (entityNames == null)
                {
                    entityNames = EntityUtility.ReadEntityNames();
                }
                return entityNames;
            }
        }

        public static bool CheckReference(Guid referenceId, Entity entity)
        {
            if (entity.Id == referenceId) return false;

            foreach (var value in entity.Attributes)
            {
                switch (value.Value.GetType().Name)
                {
                    case "Guid":
                        if ((Guid)value.Value == referenceId)
                        {
                            return true;
                        }
                        break;
                    case "EntityReference":
                        if (((EntityReference)value.Value).Id == referenceId)
                        {
                            return true;
                        }
                        break;
                    case "EntityCollection":
                        foreach (Entity innerEntity in ((EntityCollection)value.Value).Entities)
                        {
                            if (CheckReference(referenceId, innerEntity))
                            {
                                return true;
                            }
                        }
                        break;
                }
            }

            return false;
        }

        public static bool CheckReference(Guid referenceId, EntityCollection collection)
        {
            bool ret = false;

            foreach (Entity entity in collection.Entities)
            {
                if (CheckReference(referenceId, entity))
                {
                    References.Add(new EntityLink(entity.LogicalName, entity.Id));
                    ret = true;
                    return true;
                }
            }

            return ret;
        }

        public static List<EntityLink> CheckReference(string logicalName, Guid guid)
        {
            try
            {
                References = new List<EntityLink>();

                Entity referenceEntity = EntityUtility.ReadEntity(logicalName, guid);

                string[] entities = EntityNames;

                foreach (string entity in entities)
                {
                    Debug.WriteLine(entity);
                    EntityCollection collection = EntityUtility.ReadEntities(entity);
                    CheckReference(referenceEntity.Id, collection);
                }
            }
            catch (Exception ex)
            {
                Debug.WriteLine(string.Format("Entity not found: {0}", ex.Message));
                return null;
            }

            return References;
        }

        public static List<EntityLink> CheckReference(Entity entity)
        {
            return CheckReference(entity.LogicalName, entity.Id);
        }
    }
}