using System;
using System.Collections.Generic;
using System.Diagnostics.CodeAnalysis;
using System.Linq;
using System.Windows;
using InABox.Clients;
using InABox.Core;

namespace InABox.DynamicGrid
{
    /// <summary>
    ///     Interaction logic for FormDesigner.xaml
    /// </summary>
    public partial class DynamicFormEditWindow : DynamicFormWindow
    {
        public enum FormResult
        {
            None,
            Cancel,
            Save,
            Complete
        }

        public DynamicFormEditWindow()
        {
            InitializeComponent();
            Grid.OnChanged += Grid_OnChanged;

            //Complete.IsEnabled = Security.IsAllowed<CanChangeDigitalFormCompletion>();
        }

        protected override DynamicFormDesignGrid Grid { get => Preview; }

        public FormMode Mode
        {
            get => Grid.Mode;
            private set => Grid.Mode = value;
        }

        public FormResult Result = FormResult.None;

        public IDigitalFormDataModel? DataModel
        {
            get => Grid.DataModel;
            set
            {
                Grid.DataModel = value;
                RefreshEnabled();
            }
        }

        /// <summary>
        /// Gets or sets the values in the form; can only be accessed after <see cref="DynamicFormDesignGrid.Initialize"/>.
        /// </summary>
        public Dictionary<string, object> Values
        {
            get => Grid.SaveValues();
            set
            {
                Grid.LoadValues(value);
                RefreshEnabled();
            }
        }

        private bool IsReopening = false;
        private bool HasChanged = false;

        private void RefreshEnabled()
        {
            var formInstance = DataModel!.Instance;
            var completed = formInstance.FormCompleted;

            CompletedDate.Content = !completed.IsEmpty() ? $"Completed {completed:d MMM yyyy} at {completed:hh:mm tt}" : "Not completed yet";

            if (completed.IsEmpty()
                && DFUtils.CanEditForm(formInstance.GetType(), formInstance, DataModel.Entity))
            {
                Mode = FormMode.Filling;
            }
            else
            {
                Mode = Security.IsAllowed<CanEditCompletedForms>()
                    ? FormMode.Editing
                    : FormMode.ReadOnly;
            }

            if (Mode == FormMode.Editing || Mode == FormMode.Filling || Mode == FormMode.Preview)
            {
                SaveForm.IsEnabled = Grid.IsChanged || HasChanged;
            }
            else
            {
                SaveForm.IsEnabled = false;
            }

            if (!completed.IsEmpty() && Security.IsAllowed<CanChangeDigitalFormCompletion>())
            {
                CompleteForm.Content = "Re-open form";
                CompleteForm.IsEnabled = true;
                IsReopening = true;
            }
            else
            {
                CompleteForm.Content = "Complete form";
                CompleteForm.IsEnabled = Mode == FormMode.Filling && DataModel?.Instance.FormCompleted == DateTime.MinValue;
                IsReopening = false;
            }
        }

        private void Grid_OnChanged(DynamicFormDesignGrid sender, string fieldName)
        {
            if (Mode == FormMode.Editing || Mode == FormMode.Filling || Mode == FormMode.Preview)
            {
                SaveForm.IsEnabled = true;
            }
        }

        private void Cancel_Click(object sender, RoutedEventArgs e)
        {
            Result = FormResult.Cancel;
            DialogResult = false;
        }

        private void Complete()
        {
            if (!Grid.Validate(out var messages))
            {
                MessageBox.Show(string.Join('\n', messages));
                return;
            }
            if (MessageBox.Show("Are you sure you want to complete this form?", "Confirm Completion", MessageBoxButton.YesNo) == MessageBoxResult.Yes)
            {
                Result = FormResult.Complete;
                DialogResult = true;
            }
        }
        private void Reopen()
        {
            HasChanged = true;
            DataModel!.Instance.FormCompleted = DateTime.MinValue;
            DataModel!.Instance.FormCompletedBy.Clear();
            RefreshEnabled();
        }

        private void CompleteForm_Click(object sender, RoutedEventArgs e)
        {
            if (IsReopening)
                Reopen();
            else
                Complete();
        }

        private void SaveForm_Click(object sender, RoutedEventArgs e)
        {
            if (DataModel?.Instance.FormCompleted.IsEmpty() == false && !Grid.Validate(out var messages))
            {
                MessageBox.Show(string.Join('\n', messages));
                return;
            }
            if (MessageBox.Show("Are you sure you want to save this form?", "Confirm Save", MessageBoxButton.YesNo) == MessageBoxResult.Yes)
            {
                Result = FormResult.Save;
                DialogResult = true;
            }
        }
        public static bool EditDigitalForm(IDigitalFormInstance formInstance, [NotNullWhen(true)] out IDigitalFormDataModel? dataModel)
        {
            dataModel = null;
            var formid = formInstance.Form.ID;
            var formdata = formInstance.FormData;

            var parentlink = CoreUtils.HasProperty(formInstance.GetType(), "Parent") ? CoreUtils.GetPropertyValue(formInstance, "Parent") as IEntityLink : null;
            var parenttype = parentlink?.GetType().BaseType?.GetGenericArguments().FirstOrDefault();

            var results = Client.QueryMultiple(
                new KeyedQueryDef<DigitalFormVariable>(new Filter<DigitalFormVariable>(x => x.Form.ID).IsEqualTo(formid)),
                new KeyedQueryDef<DigitalFormLayout>(
                    new Filter<DigitalFormLayout>(x => x.Form.ID).IsEqualTo(formid)
                        .And(x => x.Active).IsEqualTo(true)
                        .And(x => x.Layout).IsNotEqualTo("")));

            var variables = results[nameof(DigitalFormVariable)].Rows.Select(x => x.ToObject<DigitalFormVariable>()).ToArray();
            var layout = results[nameof(DigitalFormLayout)].Rows.FirstOrDefault()?.ToObject<DigitalFormLayout>();

            Entity? parent = null;
            if (parenttype != null && parentlink != null)
            {
                var parentid = parentlink.ID;
                var filter = Filter.Create(parenttype);
                filter.Expression = CoreUtils.GetMemberExpression(parenttype, "ID");
                filter.Operator = Operator.IsEqualTo;
                filter.Value = parentid;

                var client = (Activator.CreateInstance(typeof(Client<>).MakeGenericType(parenttype)) as Client)!;
                parent = client.Query(filter, null, null).Rows.FirstOrDefault()?.ToObject(parenttype) as Entity;
            }

            if (layout == null)
                return false;
            if (parent == null)
            {
                Logger.Send(LogType.Error, "", $"Form parent is null; Form Type: {formInstance.GetType()}; Parent Type: {parenttype}; Form ID: {formInstance.ID}");
                MessageBox.Show("An error occurred while loading the form: Form Entity is null");
                return false;
            }

            var form = new DynamicFormEditWindow
            {
                Type = layout.Type,
                Title = string.Format("Viewing {0}", formInstance.Form.Description.SplitCamelCase())
                //Completed = !formInstance.FormCompleted.IsEmpty()
            };

            form.LoadLayout(layout, variables);

            try
            {
                dataModel = formInstance.CreateDataModel(parent);
                form.DataModel = dataModel;
            }
            catch (Exception e)
            {
                Logger.Send(LogType.Error, ClientFactory.UserID, $"Error during Edit Form / CreateDataModel: {CoreUtils.FormatException(e)}");
            }

            form.Initialize();

            if (!string.IsNullOrWhiteSpace(formdata))
                form.Values = Serialization.Deserialize<Dictionary<string, object>>(formdata);

            if (form.ShowDialog() == true)
            {
                if (form.Result == FormResult.Complete)
                {
                    formInstance.FormCompleted = DateTime.Now;
                    formInstance.FormCompletedBy.ID = ClientFactory.UserGuid;
                    formInstance.FormCompletedBy.UserID = ClientFactory.UserID;
                    /*formInstance.FormCompleted = form.Completed
                        ? formInstance.FormCompleted.IsEmpty()
                            ? DateTime.Now
                            : formInstance.FormCompleted
                        : DateTime.MinValue;

                    formInstance.FormCompletedBy.ID = form.Completed
                        ? !formInstance.FormCompletedBy.IsValid()
                            ? ClientFactory.UserGuid
                            : formInstance.FormCompletedBy.ID
                        : Guid.Empty;

                    formInstance.FormCompletedBy.UserID = form.Completed
                        ? string.IsNullOrWhiteSpace(formInstance.FormCompletedBy.UserID)
                            ? ClientFactory.UserID
                            : formInstance.FormCompletedBy.UserID
                        : "";*/
                }
                formInstance.FormData = Serialization.Serialize(form.Values);
            }

            return form.Result == FormResult.Save || form.Result == FormResult.Complete;
        }

        private void DynamicFormWindow_Closing(object sender, System.ComponentModel.CancelEventArgs e)
        {
            if(DialogResult != true && (HasChanged || Grid.IsChanged))
            {
                if(MessageBox.Show("This form has unsaved changes. Do you wish to discard them?", "Discard Changes?", MessageBoxButton.YesNo) != MessageBoxResult.Yes)
                {
                    e.Cancel = true;
                }
            }
        }
    }
}