using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Linq;
using System.Runtime.CompilerServices;
using System.Windows;
using System.Windows.Media.Imaging;
using Comal.Classes;
using Geocoding;
using InABox.Core;
using InABox.DynamicGrid;
using InABox.WPF;

namespace PRSDesktop
{
    public class AssignmentAppointment : CalendarAppointment<Assignment>
    {
        public CalendarAssignmentType AssignmentType { get; }

        public override TimeSpan StartTime
        {
            get => AssignmentType switch
            {
                CalendarAssignmentType.Booked => Model.Booked.Start,
                CalendarAssignmentType.Actual => Model.Actual.Start,
                _ => Model.EffectiveStartTime()
            };
            set
            {
                switch (AssignmentType)
                {
                    case CalendarAssignmentType.Automatic:
                    case CalendarAssignmentType.Actual:
                        Model.Actual.Start = value;
                        break;
                    case CalendarAssignmentType.Booked:
                        Model.Booked.Start = value;
                        break;
                }
                OnUpdate?.Invoke();
            }
        }
            

        public override TimeSpan EndTime
        {
            get => AssignmentType switch
            {
                CalendarAssignmentType.Booked => Model.Booked.Finish,
                CalendarAssignmentType.Actual => Model.Actual.Finish,
                _ => Model.EffectiveFinishTime()
            };
            set
            {
                switch (AssignmentType)
                {
                    case CalendarAssignmentType.Automatic:
                    case CalendarAssignmentType.Actual:
                        Model.Actual.Finish = value;
                        break;
                    case CalendarAssignmentType.Booked:
                        Model.Booked.Finish = value;
                        break;
                }
                OnUpdate?.Invoke();
            }
        }

        public override bool CanAdjust => true;

        public override DateTime Date
        {
            get => Model.Date;
            set
            {
                Model.Date = value;
                OnUpdate?.Invoke();
            }
        }

        public override Employee? Employee
        {
            get => base.Employee;
            set
            {
                base.Employee = value;
                Model.EmployeeLink.ID = value?.ID ?? Guid.Empty;
                OnUpdate?.Invoke();
            }
        }

        public event Action? OnUpdate;
        
        public AssignmentAppointment(Assignment model, Employee employee, CalendarAssignmentType type)
            : base(model, employee, x => x.ActivityLink.Color)
        {
            AssignmentType = type;
            
            Notes = Model.Description;

            Subject = GetSubject();

            Image = GetImage();

            WeakEventManager<Assignment, PropertyChangedEventArgs>.AddHandler(model, nameof(Assignment.PropertyChanged), Assignment_Changed);
        }

        private static Column<Assignment>[] SubjectColumns = [
            new(x => x.Number),
            new(x => x.JobLink.JobNumber),
            new(x => x.ITP.Code),
            new(x => x.Task.Number),
            new(x => x.Meeting.Link.Number),
            new(x => x.Title),
            ];

        private string GetSubject()
        {
            var subject = new List<string>() { Model.Number.ToString() };
            if (Model.JobLink.ID != Guid.Empty)
                subject.Add(
                    Model.ITP.ID != Guid.Empty
                        ? $"{Model.JobLink.JobNumber}-{Model.ITP.Code}"
                        : $"{Model.JobLink.JobNumber}"
                );
            if (Model.Task.ID  != Guid.Empty)
                subject.Add($"Task {Model.Task.Number}");
            if (Model.Meeting.Link.ID  != Guid.Empty)
                subject.Add($"Mtg {Model.Meeting.Link.Number}");
            
            subject.Add(Model.Title ?? "");
            return string.Join(" ", subject);
        }

        private static Column<Assignment>[] ImageColumns = [
            new(x => x.Completed),
            new(x => x.Delivery.ID),
            new(x => x.Meeting.Link.ID),
            ];

        private BitmapImage? GetImage()
        {
            var images = new List<Bitmap>();
            if (!Model.Completed.IsEmpty())
                images.Add(Resources.tick_sml.Resize(32,32));
            if (Model.Delivery.ID != Guid.Empty)
                images.Add(Resources.box_sml.Resize(32,32));
            if (Model.Meeting.Link.ID != Guid.Empty)
                images.Add(Resources.employees.Resize(32,32));
            return ImageUtils.MergeBitmaps(images, 10)?.AsBitmapImage();
        }

        private static Column<Assignment>[] StartColumns = [
            new(x => x.Booked.Start),
            new(x => x.Actual.Start),
            ];
        private static Column<Assignment>[] FinishColumns = [
            new(x => x.Booked.Finish),
            new(x => x.Actual.Finish),
            ];

        private void Assignment_Changed(object? sender, PropertyChangedEventArgs e)
        {
            if(StartColumns.Any(x => x.Property == e.PropertyName))
            {
                OnPropertyChanged(nameof(StartTime));
            }
            else if(FinishColumns.Any(x => x.Property == e.PropertyName))
            {
                OnPropertyChanged(nameof(EndTime));
            }
            else if(e.PropertyName == nameof(Assignment.Date))
            {
                OnPropertyChanged(nameof(Date));
            }
            else if(e.PropertyName == $"{nameof(Assignment.EmployeeLink)}.{nameof(Employee.ID)}")
            {
                EmployeeChanged?.Invoke(this, new());
            }

            if(SubjectColumns.Any(x => x.Property == e.PropertyName))
            {
                Subject = GetSubject();
                OnPropertyChanged(nameof(Subject));
            }
            else if(e.PropertyName == nameof(Assignment.Description))
            {
                Notes = Model.Description;
                OnPropertyChanged(nameof(Notes));
            }
            else if(e.PropertyName == $"{nameof(Assignment.ActivityLink)}.{nameof(Assignment.ActivityLink.Color)}")
            {
                UpdateColour();
                OnPropertyChanged(nameof(Background));
                OnPropertyChanged(nameof(Foreground));
            }

            if(ImageColumns.Any(x => x.Property == e.PropertyName))
            {
                Image = GetImage();
                OnPropertyChanged(nameof(Image));
            }
        }

        public event EventHandler<EventArgs>? EmployeeChanged;
    }
}