using Microsoft.EntityFrameworkCore;
using System.Linq;
using System.Windows;
using System.Windows.Controls;
using Elwig.Helpers;
using Elwig.Models.Entities;
using System;
using System.Threading.Tasks;
using System.Collections.Generic;
using Microsoft.EntityFrameworkCore.ChangeTracking;
using Xceed.Wpf.Toolkit.Primitives;

namespace Elwig.Windows {
    public partial class AreaComAdminWindow : AdministrationWindow {
        private readonly Member Member;
        private List<string> TextFilter = new();

        public AreaComAdminWindow(int mgnr) {
            InitializeComponent();
            Member = Context.Members.Find(mgnr) ?? throw new ArgumentException("MgNr argument has invalid value");
            Title = $"Flächenbindungen - {Member.AdministrativeName} - Elwig";
            ExemptInputs = new Control[] {
                MgNrInput, AreaCommitmentList, NewAreaCommitmentButton, 
                EditAreaCommitmentButton, DeleteAreaCommitmentButton, AreaCommitmentSaveButton,
                AreaCommitmentResetButton, AreaCommitmentCancelButton, SearchInput, ActiveAreaCommitmentInput
            };
            RequiredInputs = new Control[] {
                FbNrInput, YearFromInput, KgInput, RdInput,
                GstNrInput, AreaInput.TextBox, AreaComTypeInput, WineCultivationInput
            };
        }

        private void Window_Loaded(object sender, RoutedEventArgs e) {
            ActiveAreaCommitmentInput.IsChecked = true;
            LockInputs();
        }

        private async Task RefreshAreaCommitmentList() {
            await Context.AreaCommitments.LoadAsync();
            await RefreshAreaCommitmentListQuery();
        }

        private async Task RefreshAreaCommitmentListQuery(bool updateSort = false) {
            var (_, areaComQuery, filter) = await GetFilters();
            var areaComs = await areaComQuery.ToListAsync();

            if (filter.Count > 0 && areaComs.Count > 0) {
                var dict = areaComs.AsParallel()
                    .ToDictionary(d => d, d => d.SearchScore(TextFilter))
                    .OrderByDescending(c => c.Value);
                var threshold = dict.Select(a => a.Value).Max() * 3 / 4;
                areaComs = dict
                    .Where(a => a.Value > threshold)
                    .Select(a => a.Key)
                    .ToList();
            }

            ControlUtils.RenewItemsSource(AreaCommitmentList, areaComs, i => (i as AreaCom)?.FbNr,
                AreaCommitmentList_SelectionChanged, filter.Count > 0 ? ControlUtils.RenewSourceDefault.IfOnly : ControlUtils.RenewSourceDefault.None, !updateSort);
            RefreshInputs();

            if(filter.Count == 0) {
                StatusAreaCommitments.Text = $"Flächenbindungen: {await areaComQuery.CountAsync()}";
                StatusArea.Text = $"Fläche: {await areaComQuery.Select(a => a.Area).SumAsync():N0} m²";
            } else {
                StatusAreaCommitments.Text = $"Flächenbindungen: {areaComs.Count}";
                StatusArea.Text = $"Fläche: {areaComs.Select(a => a.Area).Sum():N0} m²";
            }
            var groups = areaComs.GroupBy(a => a.AreaComType.DisplayName).Select(a => (a.Key, a.Sum(b => b.Area))).OrderByDescending(a => a.Item2).ToList();
            StatusContracts.Text = $"Vertragsarten: {groups.Count} (" + string.Join(", ", groups.Select(g => $"{g.Key}: {g.Item2:N0} m²")) + ")";
            StatusContracts.ToolTip = $"Vertragsarten: {groups.Count}\n" + string.Join($"\n", groups.Select(g => $"{g.Key}: {g.Item2:N0} m²"));
        }

        private async Task<(List<string>, IQueryable<AreaCom>, List<string>)> GetFilters() {
            List<string> filterNames = new();
            IQueryable<AreaCom> areaComQuery = Context.AreaCommitments.Where(a => a.MgNr == Member.MgNr).OrderBy(a => a.FbNr);
            if (ActiveAreaCommitmentInput.IsChecked == true) {
                areaComQuery = areaComQuery.Where(a => a.YearTo == null);
                filterNames.Add("ohne Enddatum");
            }

            var filterVar = new List<string>();
            var filterNotVar = new List<string>();
            var filterAttr = new List<string>();
            var filterNotAttr = new List<string>();

            var filter = TextFilter.ToList();
            if (filter.Count > 0) {
                var var = await Context.WineVarieties.ToDictionaryAsync(v => v.SortId, v => v);
                var attr = await Context.WineAttributes.ToDictionaryAsync(a => a.Name.ToLower().Split(" ")[0], a => a);

                for (int i = 0; i < filter.Count; i++) {
                    var e = filter[i];
                    if (e.Length == 2 && var.ContainsKey(e.ToUpper())) {
                        filterVar.Add(e.ToUpper());
                        filter.RemoveAt(i--);
                        filterNames.Add(var[e.ToUpper()].Name);
                    } else if (e.Length == 3 && e[0] == '!' && var.ContainsKey(e[1..].ToUpper())) {
                        filterNotVar.Add(e[1..].ToUpper());
                        filter.RemoveAt(i--);
                    } else if (attr.ContainsKey(e.ToLower())) {
                        var a = attr[e.ToLower()];
                        filterAttr.Add(a.AttrId);
                        filter.RemoveAt(i--);
                        filterNames.Add($"Attribut {a.Name}");
                    } else if (e[0] == '!' && attr.ContainsKey(e[1..].ToLower())) {
                        var a = attr[e[1..].ToLower()];
                        filterNotAttr.Add(a.AttrId);
                        filter.RemoveAt(i--);
                        filterNames.Add($"ohne Attribut {a.Name}");
                    }
                }

                if (filterVar.Count > 0) areaComQuery = areaComQuery.Where(a => filterVar.Contains(a.AreaComType.WineVar.SortId));
                if (filterNotVar.Count > 0) areaComQuery = areaComQuery.Where(a => !filterNotVar.Contains(a.AreaComType.WineVar.SortId));
                if (filterAttr.Count > 0) areaComQuery = areaComQuery.Where(a => a.AreaComType.WineAttr != null && a.AreaComType.WineAttr.AttrId != null && filterAttr.Contains(a.AreaComType.WineAttr.AttrId));
                if (filterNotAttr.Count > 0) areaComQuery = areaComQuery.Where(a => a.AreaComType.WineAttr == null || a.AreaComType.WineAttr.AttrId == null || !filterAttr.Contains(a.AreaComType.WineAttr.AttrId));
            }

           return (filterNames, areaComQuery, filter);
        }

        private void RefreshInputs(bool validate = false) {
            ClearInputStates();
            if (AreaCommitmentList.SelectedItem is AreaCom a) {
                EditAreaCommitmentButton.IsEnabled = true;
                DeleteAreaCommitmentButton.IsEnabled = true;
                FillInputs(a);
            } else {
                EditAreaCommitmentButton.IsEnabled = false;
                DeleteAreaCommitmentButton.IsEnabled = false;
                ClearOriginalValues();
                ClearDefaultValues();
                ClearInputs(validate);
                ClearInputStates();
            }
            GC.Collect();
        }

        private void FillInputs(AreaCom a) {
            ClearOriginalValues();
            ClearDefaultValues();

            FbNrInput.Text = a.FbNr.ToString();
            MgNrInput.Text = a.MgNr.ToString();
            YearFromInput.Text = a.YearFrom.ToString();
            YearToInput.Text = a.YearTo.ToString();

            KgInput.SelectedItem = a.Kg.AtKg;
            RdInput.SelectedItem = a.Rd;
            GstNrInput.Text = a.GstNr;
            AreaInput.Text = a.Area.ToString();

            AreaComTypeInput.SelectedItem = a.AreaComType;
            WineCultivationInput.SelectedItem = a.WineCult;

            CommentInput.Text = a.Comment;

            FinishInputFilling();
        }

        private async void InitInputs() {
            ClearOriginalValues();
            ClearDefaultValues();

            FbNrInput.Text = (await Context.NextFbNr()).ToString();
            MgNrInput.Text = Member.MgNr.ToString();

            SetDefaultValue(FbNrInput);
            ValidateRequiredInputs();
        }

        protected override async Task OnRenewContext() {
            await base.OnRenewContext();
            ControlUtils.RenewItemsSource(KgInput, await Context.WbKgs.Select(k => k.AtKg).OrderBy(k => k.Name).ToListAsync(), i => (i as AT_Kg)?.KgNr);
            ControlUtils.RenewItemsSource(AreaComTypeInput, await Context.AreaCommitmentTypes.OrderBy(v => v.VtrgId).ToListAsync(), i => (i as AreaComType)?.VtrgId);
            ControlUtils.RenewItemsSource(WineCultivationInput, await Context.WineCultivations.OrderBy(c => c.Name).ToListAsync(), i => (i as WineCult)?.CultId);
            await RefreshAreaCommitmentList();
        }

        private void NewAreaCommitmentButton_Click(object sender, RoutedEventArgs evt) {
            IsCreating = true;
            AreaCommitmentList.IsEnabled = false;
            AreaCommitmentList.SelectedItem = null;
            HideAreaCommitmentNewEditDeleteButtons();
            ShowAreaCommitmentSaveResetCancelButtons();
            UnlockInputs();
            InitInputs();
            LockSearchInputs();
        }

        private void EditAreaCommitmentButton_Click(object sender, RoutedEventArgs evt) {
            if (AreaCommitmentList.SelectedItem == null)
                return;

            IsEditing = true;
            AreaCommitmentList.IsEnabled = false;

            HideAreaCommitmentNewEditDeleteButtons();
            ShowAreaCommitmentSaveResetCancelButtons();
            UnlockInputs();
            LockSearchInputs();
        }

        private async void DeleteAreaCommitmentButton_Click(object sender, RoutedEventArgs evt) {
            AreaCom a = (AreaCom)AreaCommitmentList.SelectedItem;
            if (a == null) return;

            var r = MessageBox.Show(
                $"Soll die Flächenbindung {a.GstNr} ({a.Area} m²) wirklich unwiderruflich gelöscht werden?",
                "Flächenbindung löschen", MessageBoxButton.YesNo, MessageBoxImage.Warning, MessageBoxResult.No);
            if (r == MessageBoxResult.Yes) {
                Context.Remove(a);
                Context.SaveChanges();
                await RefreshAreaCommitmentList();
            }
        }

        private async Task<AreaCom> UpdateAreaCom(AreaCom a) {
            int newFbNr = int.Parse(FbNrInput.Text);
            a.MgNr = int.Parse(MgNrInput.Text);
            a.YearFrom = int.Parse(YearFromInput.Text);
            a.YearTo = (YearToInput.Text == "") ? null : int.Parse(YearToInput.Text);
            a.KgNr = ((AT_Kg)KgInput.SelectedItem).KgNr;
            a.RdNr = RdInput.SelectedItem.GetType() == typeof(NullItem) ? null : ((WbRd)RdInput.SelectedItem).RdNr;
            a.GstNr = GstNrInput.Text;
            a.Area = int.Parse(AreaInput.Text);
            a.VtrgId = (AreaComTypeInput.SelectedItem as AreaComType)?.VtrgId;
            a.CultId = (WineCultivationInput.SelectedItem as WineCult)?.CultId;
            a.Comment = (CommentInput.Text == "") ? null : CommentInput.Text;

            EntityEntry<AreaCom>? tr = null;
            try {
                if (IsEditing) {
                    tr = Context.Update(a);
                } else if (IsCreating) {
                    a.FbNr = newFbNr;
                    tr = (await Context.AddAsync(a));
                } else {
                    throw new Exception();
                }

                await Context.SaveChangesAsync();

                if (newFbNr != a.FbNr) {
                    await Context.Database.ExecuteSqlAsync($"UPDATE area_commitment SET fbnr = {newFbNr} WHERE fbnr = {a.FbNr}");
                    tr.State = EntityState.Detached;
                    await Context.SaveChangesAsync();
                    await tr.ReloadAsync();
                    a = await Context.AreaCommitments.FindAsync(newFbNr);
                }

            } catch (Exception exc) {
                if (tr != null) {
                    tr.State = EntityState.Detached;
                    await tr.ReloadAsync();
                }
                var str = "Der Eintrag konnte nicht in der Datenbank aktualisiert werden!\n\n" + exc.Message;
                if (exc.InnerException != null) str += "\n\n" + exc.InnerException.Message;
                MessageBox.Show(str, "Flächenbindung aktualisieren", MessageBoxButton.OK, MessageBoxImage.Error);
            }

            return a;
        }

        private async void AreaCommitmentSaveButton_Click(object sender, RoutedEventArgs evt) {
            AreaCom a = await UpdateAreaCom(IsEditing ? (AreaCom)AreaCommitmentList.SelectedItem : Context.CreateProxy<AreaCom>());
            IsEditing = false;
            IsCreating = false;
            AreaCommitmentList.IsEnabled = true;
            HideAreaCommitmentSaveResetCancelButtons();
            ShowAreaCommitmentNewEditDeleteButtons();
            LockInputs();
            UnlockSearchInputs();
            await RefreshAreaCommitmentList();
            AreaCommitmentList.SelectedItem = a;
        }

        private void AreaCommitmentResetButton_Click(object sender, RoutedEventArgs evt) {
            if (IsEditing) {
                RefreshInputs();
            } else if (IsCreating) {
                InitInputs();
            }
            UpdateButtons();
        }

        private void AreaCommitmentCancelButton_Click(object sender, RoutedEventArgs evt) {
            IsEditing = false;
            IsCreating = false;
            AreaCommitmentList.IsEnabled = true;
            HideAreaCommitmentSaveResetCancelButtons();
            ShowAreaCommitmentNewEditDeleteButtons();
            RefreshInputs();
            ClearInputStates();
            LockInputs();
            UnlockSearchInputs();
        }

        override protected void UpdateButtons() {
            if (!IsEditing && !IsCreating) return;
            bool ch = HasChanged, v = IsValid;
            AreaCommitmentResetButton.IsEnabled = (ch);
            AreaCommitmentSaveButton.IsEnabled = (ch && v);
        }

        private void DisableAreaCommitmentNewEditDeleteButtons() {
            NewAreaCommitmentButton.IsEnabled = false;
            EditAreaCommitmentButton.IsEnabled = false;
            DeleteAreaCommitmentButton.IsEnabled = false;
        }

        private void EnableAreaCommitmentNewEditDeleteButtons() {
            NewAreaCommitmentButton.IsEnabled = true;
            EditAreaCommitmentButton.IsEnabled = AreaCommitmentList.SelectedItem != null;
            DeleteAreaCommitmentButton.IsEnabled = AreaCommitmentList.SelectedItem != null;
        }

        private void ShowAreaCommitmentSaveResetCancelButtons() {
            AreaCommitmentSaveButton.IsEnabled = false;
            AreaCommitmentResetButton.IsEnabled = false;
            AreaCommitmentCancelButton.IsEnabled = true;
            AreaCommitmentSaveButton.Visibility = Visibility.Visible;
            AreaCommitmentResetButton.Visibility = Visibility.Visible;
            AreaCommitmentCancelButton.Visibility = Visibility.Visible;
        }

        private void HideAreaCommitmentSaveResetCancelButtons() {
            AreaCommitmentSaveButton.IsEnabled = false;
            AreaCommitmentResetButton.IsEnabled = false;
            AreaCommitmentCancelButton.IsEnabled = false;
            AreaCommitmentSaveButton.Visibility = Visibility.Hidden;
            AreaCommitmentResetButton.Visibility = Visibility.Hidden;
            AreaCommitmentCancelButton.Visibility = Visibility.Hidden;
        }

        private void ShowAreaCommitmentNewEditDeleteButtons() {
            EnableAreaCommitmentNewEditDeleteButtons();
            NewAreaCommitmentButton.Visibility = Visibility.Visible;
            EditAreaCommitmentButton.Visibility = Visibility.Visible;
            DeleteAreaCommitmentButton.Visibility = Visibility.Visible;
        }

        private void HideAreaCommitmentNewEditDeleteButtons() {
            DisableAreaCommitmentNewEditDeleteButtons();
            NewAreaCommitmentButton.Visibility = Visibility.Hidden;
            EditAreaCommitmentButton.Visibility = Visibility.Hidden;
            DeleteAreaCommitmentButton.Visibility = Visibility.Hidden;
        }

        private void LockSearchInputs() {
            SearchInput.IsEnabled = false;
            ActiveAreaCommitmentInput.IsEnabled = false;
        }

        private void UnlockSearchInputs() {
            SearchInput.IsEnabled = true;
            ActiveAreaCommitmentInput.IsEnabled = true;
        }

        private void AreaCommitmentList_SelectionChanged(object sender, SelectionChangedEventArgs evt) {
            RefreshInputs();
        }

        private void AttributesInput_SelectionChanged(object sender, ItemSelectionChangedEventArgs evt) {

        }

        private async void ActiveAreaCommitmentInput_Changed(object sender, RoutedEventArgs evt) {
            await RefreshAreaCommitmentListQuery();
        }

        private async void SearchInput_TextChanged(object sender, RoutedEventArgs evt) {
            TextFilter = SearchInput.Text.ToLower().Split(" ").ToList().FindAll(e => e.Length > 0);
            await RefreshAreaCommitmentListQuery(true);
        }

        private async void KgInput_SelectionChanged(object sender, SelectionChangedEventArgs evt) {
            if (KgInput.SelectedItem is AT_Kg curr_kg) {
                var rdList = await Context.WbRde.Where(r => r.KgNr == curr_kg.KgNr).OrderBy(r => r.Name).Cast<object>().ToListAsync();
                rdList.Insert(0, new NullItem());
                ControlUtils.RenewItemsSource(RdInput, rdList, i => (i as WbRd)?.RdNr, null, ControlUtils.RenewSourceDefault.First);
            } else {
                var rdList = new object[] { new NullItem() };
                ControlUtils.RenewItemsSource(RdInput, rdList, i => (i as WbRd)?.RdNr, null, ControlUtils.RenewSourceDefault.First);
            }
            ComboBox_SelectionChanged(sender, evt);
        }

        protected void InputTextChanged(TextBox input, Func<TextBox, bool, AppDbContext, AreaCom?, ValidationResult> checker) {
            InputTextChanged(input, checker(input, SenderIsRequired(input), Context, (AreaCom)AreaCommitmentList.SelectedItem));
        }

        protected void InputLostFocus(TextBox input, Func<TextBox, bool, AppDbContext, AreaCom?, ValidationResult> checker, string? msg = null) {
            InputLostFocus(input, checker(input, SenderIsRequired(input), Context, (AreaCom)AreaCommitmentList.SelectedItem), msg);
        }

        private void FbNrInput_TextChanged(object sender, RoutedEventArgs evt) {
            InputTextChanged((TextBox)sender, Validator.CheckFbNr);
        }

        private void FbNrInput_LostFocus(object sender, RoutedEventArgs evt) {
            InputLostFocus((TextBox)sender, Validator.CheckFbNr);
        }
        
        private void GstNrInput_TextChanged(object sender, RoutedEventArgs evt) {
            InputTextChanged((TextBox)sender, Validator.CheckGstNr);
        }

        private void GstNrInput_LostFocus(object sender, RoutedEventArgs evt) {
            InputLostFocus((TextBox)sender, Validator.CheckGstNr);
        }
    }
}