using System;

using System.Collections.Generic;

using System.Collections.ObjectModel;

using System.Collections.Specialized;

using System.Reactive.Linq;

using Avalonia;

using Avalonia.Input.Platform;

using DesertPaintCodex.Models;

using DesertPaintCodex.Services;

using DynamicData;

using DynamicData.Binding;

using ReactiveUI;

namespace DesertPaintCodex.ViewModels

{

    public class SimulatorViewModel : ViewModelBase

    {

        private RecipeLibraryViewModel? _recipeLibraryVM;

        private ViewModelBase? _recipeLibraryActivity;

        public ViewModelBase? RecipeLibraryActivity { get => _recipeLibraryActivity; private set => this.RaiseAndSetIfChanged(ref _recipeLibraryActivity, value); }

        private PaintColor? _paintColor;

        public PaintColor? PaintColor

        {

            get => _paintColor;

            set => this.RaiseAndSetIfChanged(ref _paintColor, value);

        }

        // Stealing the recipe view from the  paint generator

        private bool _hasMissingReactions;

        public bool HasMissingReactions

        {

            get => _hasMissingReactions;

            set => this.RaiseAndSetIfChanged(ref _hasMissingReactions, value);

        }

        private bool _isGoodRecipe;

        public bool IsGoodRecipe

        {

            get => _isGoodRecipe;

            set => this.RaiseAndSetIfChanged(ref _isGoodRecipe, value);

        }

        private bool _isValidConcentration;

        public bool IsValidConcentration

        {

            get => _isValidConcentration;

            set => this.RaiseAndSetIfChanged(ref _isValidConcentration, value);

        }

        private string _missingReactionList = string.Empty;

        public string MissingReactionList

        {

            get => _missingReactionList;

            set => this.RaiseAndSetIfChanged(ref _missingReactionList, value);

        }

        public ObservableCollection<Reagent> Reagents { get; } = new();

        public ObservableCollection<Reagent> ActiveReagents { get; } = new();

        public ObservableCollection<RecipeItem> RecipeItems { get; } = new();

        private readonly PaintRecipe _currentRecipe = new();

        private PaintColor _tempColor = new PaintColor(0, 0,0);

        public SimulatorViewModel()

        {

            List<string> reagentNames = ReagentService.Names;

            for (int i = 0; i < reagentNames.Count; i++)

            {

                Reagents.Add(ReagentService.GetReagent(reagentNames[i]));

            }

            ActiveReagents.CollectionChanged += OnActiveReagentsChanged;

            RecipeItems

                .ToObservableChangeSet()

                .AutoRefresh(item => item.Quantity)

                .Subscribe(_ => Refresh());

        }

        public async void CopyToClipboard()

        {

            IClipboard clipboard = Application.Current.Clipboard;

            await clipboard.SetTextAsync(_currentRecipe.ToString());

        }

        public void MoveItemUp(RecipeItem item)

        {

            int pos = RecipeItems.IndexOf(item);

            if (pos <= 0) return;

            RecipeItems.RemoveAt(pos);

            RecipeItems.Insert(pos + 1, item);

            Refresh();

        }

        private void ShowRecipeLibrary()

        {

            _recipeLibraryVM = new RecipeLibraryViewModel();

            Observable.Merge(_recipeLibraryVM.Ok, _recipeLibraryVM.Cancel).Subscribe(_ => LoadRecipe());

            RecipeLibraryActivity = _recipeLibraryVM;

        }

        // Show the list of recipes and allow the user to pick one to load

        public void LoadRecipe()

        {

            // TODO: show the list of recipes

        }

        public void SelectRecipeToLoad(PaintRecipe recipe)

        {

            // 1: Clear the current recipe

            _currentRecipe.Clear();

            RecipeItems.Clear();

            // 2: Set the recipe items from the loaded recipe

            foreach (PaintRecipe.ReagentQuantity reagentQuantity in recipe.Reagents)

            {

                Reagent reagent = ReagentService.GetReagent(reagentQuantity.Name);

                if (reagent != null)

                {

                    RecipeItems.Add(new RecipeItem(reagent, reagentQuantity.Quantity));

                }

            }

            UpdateRecipe();

        }

        // Replace the recipe for a color with the current recipe

        public void ReplaceRecipe()

        {

            if (IsGoodRecipe && IsValidConcentration)

            {

                if (ProfileManager.CurrentProfile == null) return;

                string colorName = PaletteService.FindNearest(_currentRecipe.ReactedColor);

                _tempColor.Set(colorName, _currentRecipe.ReactedColor);

                ProfileManager.CurrentProfile.Recipes[colorName].CopyFrom(_currentRecipe);

                UpdateExistingRecipe();

            }

        }

        private void UpdateExistingRecipe()

        {

            if (IsGoodRecipe)

            {

                string colorName = PaletteService.FindNearest(_currentRecipe.ReactedColor);

                if ((ProfileManager.CurrentProfile != null) && (ProfileManager.CurrentProfile.Recipes.TryGetValue(colorName, out PaintRecipe? paintRecipe)))

                {

                    System.Diagnostics.Debug.WriteLine($"Setting existing recipe for {colorName}.");

                    ExistingRecipe = null;

                }

                else

                {

                    ExistingRecipe = null;

                }

            }

            else

            {

                ExistingRecipe = null;

            }

        }

        private void UpdateRecipe()

        {

            _currentRecipe.Clear();

            foreach (RecipeItem entry in RecipeItems)

            {

                if (!entry.Unused)

                {

                    _currentRecipe.AddReagent(entry.Reagent.Name, entry.Quantity);

                }

            }

            PaintColor = null; // TODO: Find a better way to kick the paint swatch when reassigning color from the same ref.

            PaintColor          = _currentRecipe.ReactedColor;

            HasMissingReactions = _currentRecipe.HasMissingReactions();

            if (HasMissingReactions)

            {

                List<(string, string)> missingReactions = _currentRecipe.MissingReactionPairs();

                List<string> missingReactionsStrings = new List<string>(missingReactions.Count);

                foreach ((string reagent1, string reagent2) in missingReactions)

                {

                    missingReactionsStrings.Add($"{reagent1}+{reagent2}");

                }

                MissingReactionList = string.Join(", ", missingReactionsStrings);

            }

            IsGoodRecipe        = !HasMissingReactions && _currentRecipe.IsValidForConcentration(10);

            IsValidConcentration = _currentRecipe.IsValidForConcentration(10);

            UpdateExistingRecipe();

        }

        private void OnActiveReagentsChanged(object? sender, NotifyCollectionChangedEventArgs e)

        {

            HashSet<Reagent> unmatchedReagents = new(ActiveReagents);

            for (int i = RecipeItems.Count - 1; i >= 0; i--)

            {

                bool found = false;

                foreach (Reagent reagent in ActiveReagents)

                {

                    if (reagent == RecipeItems[i].Reagent)

                    {

                        unmatchedReagents.Remove(reagent);

                        found = true;

                        break;

                    }

                }

                if (!found) RecipeItems.RemoveAt(i);

            }

            foreach (Reagent reagent in unmatchedReagents)

            {

<UserControl xmlns="https://github.com/avaloniaui"

             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

             xmlns:vm="using:DesertPaintCodex.ViewModels"

             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"

             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"

             xmlns:views="clr-namespace:DesertPaintCodex.Views"

             xmlns:models="clr-namespace:DesertPaintCodex.Models"

             mc:Ignorable="d" d:DesignWidth="600" d:DesignHeight="475"

             x:Class="DesertPaintCodex.Views.SimulatorView">

    <Design.DataContext>

        <vm:SimulatorViewModel/>

    </Design.DataContext>

    <UserControl.DataContext>

        <vm:SimulatorViewModel />

    </UserControl.DataContext>

    <UserControl.DataTemplates>

      <DataTemplate DataType="{x:Type models:GeneratorRecipe}">

        <Grid ColumnDefinitions="45,5,130,5,*" RowDefinitions="Auto" Margin="5">

          <Border Grid.Column="0" Classes="ReagentSwatch" Background="{Binding Color, Converter={StaticResource paintToBrush}, FallbackValue=#00000000}" />

          <TextBlock Grid.Column="2" VerticalAlignment="Center" Text="{Binding Color.Name}"/>

          <TextBlock Grid.Column="4" VerticalAlignment="Center" TextWrapping="Wrap" Text="{Binding Recipe}"/>

        </Grid>

      </DataTemplate>

    </UserControl.DataTemplates>

    <UserControl.Styles>

        <Style Selector="Border.ReagentSwatch">

            <Setter Property="Width" Value="20"/>

            <Setter Property="Height" Value="20"/>

        </Style>

        <Style Selector="TextBlock.Unused">

            <Setter Property="Foreground" Value="#CA7091"/>

            <Setter Property="FontStyle" Value="Italic"/>

        </Style>

    </UserControl.Styles>

  <DockPanel Classes="Activity">

        <Button DockPanel.Dock="Bottom" VerticalAlignment="Center" Margin="0 10 0 0" IsEnabled="{Binding IsGoodRecipe}" Command="{Binding CopyToClipboard}">📋 Copy Recipe to Clipboard</Button>

      <views:EmbeddedWarningBox DockPanel.Dock="Bottom" Title="🛇 INSUFFICIENT CONCENTRATION" Message="The current recipe does not have sufficient concentration of reagents." IsVisible="{Binding !IsValidConcentration}" />

      <views:EmbeddedWarningBox DockPanel.Dock="Bottom" Title="🛇 INSUFFICIENT DATA" Message="You are missing reaction data necessary for simulating this recipe." Message2="{Binding MissingReactionList}" IsVisible="{Binding HasMissingReactions}" />

    <Border Classes="ThinFrame" DockPanel.Dock="Bottom" IsVisible="{Binding ExistingRecipe, Converter={x:Static ObjectConverters.IsNotNull}}" Margin="0,0,0,10">

      <Grid ColumnDefinitions="*,50" RowDefinitions="20,*" HorizontalAlignment="Stretch" DockPanel.Dock="Bottom" >

          <TextBlock Classes="BlockHeader" Grid.Row="0" Grid.Column="0" DockPanel.Dock="Top" Margin="0 0 0 5">CURRENT RECIPE</TextBlock>

      </Grid>

    </Border>

    <Grid ColumnDefinitions="*,120" RowDefinitions="*" HorizontalAlignment="Stretch" DockPanel.Dock="Bottom" Margin="0,0,0,10">

      <views:PaintSwatchView Grid.Row="0" Grid.Column="0" ShowName="True" Color="{Binding PaintColor}"  IsVisible="true"/>

      <Button Grid.Row="0" Grid.Column="1" Margin="10 10 10 10" IsEnabled="{Binding IsGoodRecipe}"  Command="{Binding ReplaceRecipe}">

        <Panel>

        <TextBlock TextAlignment="Center" IsVisible="{Binding ExistingRecipe, Converter={x:Static ObjectConverters.IsNull}}">

Save

Recipe

        </TextBlock>

        <TextBlock TextAlignment="Center" IsVisible="{Binding ExistingRecipe, Converter={x:Static ObjectConverters.IsNotNull}}">

Replace

Recipe

        </TextBlock>

        </Panel>

      </Button>

    </Grid>

    <Grid ColumnDefinitions="200,15,*" RowDefinitions="20,*" VerticalAlignment="Stretch" Margin="0 0 0 15">

            <TextBlock Grid.Row="0" Grid.Column="0" DockPanel.Dock="Top" Classes="BlockHeader" Margin="0 0 0 5">REAGENTS</TextBlock>

            <ListBox Grid.Row="1" Grid.Column="0" Items="{Binding Reagents}" SelectedItems="{Binding ActiveReagents}" SelectionMode="Multiple,Toggle">

                <ListBox.ItemTemplate>

                    <DataTemplate>

                        <Border BorderBrush="{DynamicResource ThemeBorderLowBrush}" BorderThickness="1">

                            <CheckBox IsChecked="{Binding $parent[ListBoxItem].IsSelected}">

                                <StackPanel Orientation="Horizontal" Spacing="10">

                                    <Border Classes="ReagentSwatch" Background="{Binding Color, Converter={StaticResource paintToBrush}, FallbackValue=#00000000}" />

                                    <TextBlock Text="{Binding Name}"/>

                                </StackPanel>

                            </CheckBox>

                        </Border>

                    </DataTemplate>

                </ListBox.ItemTemplate>

            </ListBox>

            <TextBlock Grid.Row="0" Grid.Column="2" Classes="BlockHeader">RECIPE</TextBlock>

            <Border Grid.Row="1" Grid.Column="2"

                    BorderBrush="{DynamicResource ThemeBorderMidBrush}"

                    BorderThickness="{DynamicResource ThemeBorderThickness}">

                <ScrollViewer Background="{DynamicResource ThemeBackgroundBrush}">

                    <ItemsControl Items="{Binding RecipeItems}">

                        <ItemsControl.ItemTemplate>

                            <DataTemplate>

                                <Grid ColumnDefinitions="45,15,*,15,40,5,40" RowDefinitions="Auto" Margin="5">

                                    <NumericUpDown Grid.Column="0" Minimum="0" Maximum="{Binding MaxQty}" Value="{Binding Quantity}"/>

                                    <TextBlock Grid.Column="2" VerticalAlignment="Center" Text="{Binding Reagent.Name}"

                                               FontSize="16" IsVisible="{Binding !Unused}"/>

                                    <TextBlock Grid.Column="2" VerticalAlignment="Center" Text="{Binding Reagent.Name}" Classes="Unused"

                                               FontSize="16" IsVisible="{Binding Unused}"/>

                                    <Button Grid.Column="4" Command="{Binding $parent[views:SimulatorView].DataContext.MoveItemUp}"

                                            CommandParameter="{Binding}"

                                            IsEnabled="{Binding !First}">▲</Button>

                                    <Button Grid.Column="6" Command="{Binding $parent[views:SimulatorView].DataContext.MoveItemDown}"

                                            CommandParameter="{Binding}"

                                            IsEnabled="{Binding !Last}">▼</Button>

                                </Grid>

                            </DataTemplate>

                        </ItemsControl.ItemTemplate>

                    </ItemsControl>

                </ScrollViewer>

            </Border>

        </Grid>

    </DockPanel>