using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows;
using System.Windows.Media.Imaging;
using InABox.Core;
using InABox.WPF;

namespace InABox.DynamicGrid
{
    public class DynamicImportMappingGrid : DynamicGrid<ImportMapping>
    {
        private readonly BitmapImage create = Wpf.Resources.tick.AsBitmapImage();

        private readonly BitmapImage key = Wpf.Resources.key.AsBitmapImage();

        private readonly BitmapImage restrict = Wpf.Resources.warning.AsBitmapImage();

        public DynamicImportMappingGrid()
        {
            UniqueCode = "";

            HideBlank = false;

            Items = new List<ImportMapping>();
            Options.AddRange(DynamicGridOption.RecordCount, DynamicGridOption.DirectEdit);

            ActionColumns.Add(new DynamicImageColumn(KeyImage, KeyAction) { Position = DynamicActionColumnPosition.Start, ToolTip = KeyToolTip });
            HiddenColumns.Add(x => x.Key);


            ActionColumns.Add(new DynamicImageColumn(LookupImage, LookupAction) { ToolTip = LookupToolTip });
            HiddenColumns.Add(x => x.Lookup);
        }

        public List<ImportMapping> Items { get; }

        public string UniqueCode { get; set; }

        public bool HideBlank { get; set; }

        protected override void DeleteItems(params CoreRow[] rows)
        {
            var deletes = new List<ImportMapping>();
            foreach (var row in rows)
                deletes.Add(Items[row.Index]);
            Items.RemoveAll(x => deletes.Contains(x));
        }

        protected override ImportMapping LoadItem(CoreRow row)
        {
            return Items[row.Index];
        }

        protected override void Reload(Filters<ImportMapping> criteria, Columns<ImportMapping> columns, ref SortOrder<ImportMapping>? sort,
            Action<CoreTable?, Exception?> action)
        {
            Lookups.Clear();
            var result = new CoreTable();
            result.LoadColumns(typeof(ImportMapping));
            if (HideBlank)
                result.LoadRows(Items.Where(x => !string.IsNullOrWhiteSpace(x.Field) || !string.IsNullOrWhiteSpace(x.Constant)));
            else
                result.LoadRows(Items);
            action.Invoke(result, null);
        }

        public override void SaveItem(ImportMapping item)
        {
            if (!Items.Contains(item))
                Items.Add(item);
        }

        private FrameworkElement? KeyToolTip(DynamicActionColumn column, CoreRow? row)
        {
            var result = "";
            if (row == null)
                result = "This column is used to indicate which fields form the unique key imported records";
            else
            {
                var key = row.Get<ImportMapping, bool>(x => x.Key);
                result = key
                    ? "This field forms part (or all) of the unique key for imported records"
                    : "";
            }
            return column.TextToolTip(result);
        }

        private FrameworkElement? LookupToolTip(DynamicActionColumn column, CoreRow? row)
        {
            var result = "";
            if (row == null)
                result = "This column determines whether or not lookup values are automatically created as required, or cause the import to fail.";
            else
            {
                var lookup = row.Get<ImportMapping, ImportLookupType>(x => x.Lookup);
                result = lookup == ImportLookupType.None
                    ? ""
                    : lookup == ImportLookupType.Create
                        ? "Create Lookup Values as required"
                        : "Restrict Importing for invalid / non-existent Lookup Values";
            }
            return column.TextToolTip(result);
        }

        public void Reset()
        {
            foreach (var item in Items)
            {
                item.Key = false;
                item.Field = "";
                item.Constant = "";
                item.Lookup = item.Lookup == ImportLookupType.Create ? ImportLookupType.Restrict : item.Lookup;
            }

            Refresh(false, true);
        }

        public void MatchFields()
        {
            foreach (var item in Items)
                if (ImportFieldGenerator.Fields.Contains(item.Property))
                {
                    item.Field = item.Property;
                    if (item.Property.Equals(UniqueCode))
                        item.Key = true;
                }
                else
                {
                    item.Key = false;
                    item.Field = "";
                    item.Constant = "";
                    item.Lookup = item.Lookup == ImportLookupType.Create ? ImportLookupType.Restrict : item.Lookup;
                }

            Refresh(false, true);
        }

        private BitmapImage? KeyImage(CoreRow? arg)
        {
            if (arg == null)
                return key;
            return arg.Get<ImportMapping, bool>(x => x.Key) ? key : null;
        }

        private bool KeyAction(CoreRow? arg)
        {
            if (arg == null)
                return false;
            var item = Items[arg.Index];
            if (string.IsNullOrWhiteSpace(item.Field) && string.IsNullOrWhiteSpace(item.Constant))
                item.Key = false;
            else
                item.Key = !item.Key;
            return true;
        }

        private BitmapImage? LookupImage(CoreRow? arg)
        {
            if (arg == null)
                return restrict;

            var item = Items.FirstOrDefault(x => x.Property.Equals(arg.Get<ImportMapping, string>(c => c.Property)));

            if (item == null)
                return null;

            if (string.IsNullOrWhiteSpace(item.Field) && string.IsNullOrWhiteSpace(item.Constant))
                return null;

            return item.Lookup == ImportLookupType.Create
                ? create
                : item.Lookup == ImportLookupType.Restrict
                    ? restrict
                    : null;
        }

        private bool LookupAction(CoreRow? arg)
        {
            if (arg == null)
                return false;

            var property = arg.Get<ImportMapping, string>(c => c.Property);
            var item = Items.FirstOrDefault(x => x.Property.Equals(property));

            if (item == null || (string.IsNullOrWhiteSpace(item.Field) && string.IsNullOrWhiteSpace(item.Constant)))
                return false;

            if (item.Lookup == ImportLookupType.Restrict)
                item.Lookup = ImportLookupType.Create;
            else if (item.Lookup == ImportLookupType.Create)
                item.Lookup = ImportLookupType.Restrict;
            else
                return false;

            return true;
        }
    }
}