using InABox.Clients;
using InABox.Core;
using System;
using System.Collections.Generic;
using System.Linq;

namespace PRS.Mobile
{
    public class FormPickerQueryLoader<TEntity, TEntityLink, TInstance> : IFormPickerQueryLoader
        where TEntity : Entity, IRemotable, IPersistent, new()
        where TEntityLink : EntityLink<TEntity>, new()
        where TInstance : Entity, IRemotable, IPersistent, IDigitalFormInstance<TEntityLink>, new()
    {
        Filter<TInstance> incompleteFilter = new Filter<TInstance>(x => x.FormCompletedBy.ID).IsEqualTo(ClientFactory.UserGuid)
                .And(x => x.FormCompleted).IsEqualTo(DateTime.MinValue);

        Filter<TInstance> completeFilter = new Filter<TInstance>(x => x.FormCompletedBy.ID).IsEqualTo(ClientFactory.UserGuid)
            .And(x => x.FormCompleted).IsNotEqualTo(DateTime.MinValue);

        public List<ExistingFormShell> QueryIncomplete()
        {
            return DoQuery(incompleteFilter);
        }

        public List<ExistingFormShell> QueryComplete()
        {
            return DoQuery(completeFilter);
        }

        private List<ExistingFormShell> DoQuery(Filter<TInstance> filter)
        {
            List<ExistingFormShell> shells = new List<ExistingFormShell>();
            CoreTable table = QueryTable(filter);
            while(table == null)
                table = QueryTable(filter);
            if (table.Rows.Any())
            {
                foreach (CoreRow row in table.Rows)
                {
                    shells.Add(CreateShell(row));
                }
                //OrderShells(shells, filter);
            }
            return shells;
        }

        private CoreTable QueryTable(Filter<TInstance> filter)
        {
            try
            {
                return new Client<TInstance>().Query
                    (
                    filter,
                    new Columns<TInstance>
                    (
                        x => x.ID,
                        x => x.Parent.ID,
                        x => x.Form.Description,
                        x => x.FormStarted,
                        x => x.FormCompleted,
                        x => x.Form.ID
                    ));
            }
            catch (Exception ex)
            {
                InABox.Mobile.MobileLogging.Log(ex);
                return null;
            }
        }

        //private List<ExistingFormShell> OrderShells(List<ExistingFormShell> shells, Filter<TInstance> filter)
        //{
        //    if (filter == completeFilter)
        //        shells.Sort((x, y) => y.DateCompleted.CompareTo(x.DateCompleted)); //descending
        //    else if (filter == incompleteFilter)
        //        shells.Sort((x, y) => x.DateStarted.CompareTo(y.DateStarted));

        //    return shells;
        //}

        private ExistingFormShell CreateShell(CoreRow row)
        {
            var instance = row.ToObject<TInstance>();
            ExistingFormShell shell = new ExistingFormShell();
            shell.ID = instance.ID;
            shell.Description = instance.Form.Description;
            if (shell.Description == null)
                shell.Description = "";
            shell.ParentID = instance.Parent.ID;
            shell.DateStarted = instance.FormStarted;
            shell.DateCompleted = instance.FormCompleted;
            shell.Started = "Started: " + shell.DateStarted.ToString("dd MMM yy hh:mm tt");
            if (shell.DateCompleted != DateTime.MinValue)
                shell.Completed = "Completed: " + shell.DateCompleted.ToString("dd MMM yy hh:mm tt");
            shell.Type = typeof(TInstance);
            shell.FormID = instance.Form.ID;
            return shell;
        }
    }
}