using System.Collections.Generic;
using System.Linq;
using DonkeysAndDroids;
using Godot;
using RobotAndDonkey.Game.Cards;
using RobotAndDonkey.Game.Data;
using RobotAndDonkey.Game.Execution;
using RobotAndDonkey.Game.Execution.Commands;
using RobotAndDonkey.Game.Execution.Results;
using RobotAndDonkey.Game.Utils;

public partial class ProgramScreen : Control, IScreen
{
    public override void _Ready()
    {
        m_ProgramRow = GetNode<CardRow>("%ProgramRow");
        m_Execute = GetNode<Button>("%Execute");
        m_Discard = GetNode<Button>("%Discard");
        m_Sort = GetNode<Button>("%Sort");
        m_TapeLabel = GetNode<Label>("%TapeLabel");
        m_HandLabel = GetNode<Label>("%HandLabel");
        m_FlameBackground = GetNode<Node2D>("%FlameBackground");
        m_Execute.Pressed += OnExecutePressed;
        m_Discard.Pressed += OnDiscardPressed;
        m_Sort.Pressed += OnSortPressed;
        m_ProgramRow.Connect(CardRow.SignalName.SelectionChanged, new(this, nameof(OnSelectionChanged)));
        m_ProgramRow.Connect(CardRow.SignalName.OrderChanged, new(this, nameof(OnOrderChanged)));
        m_ProgramRow.CanChangeSelection = CanChangeSelection;
    }

    private void OnOrderChanged()
    {
        UpdateLabels();
        SendMoveCommand();
    }

    private void SendMoveCommand()
    {
        if (Main.Instance.CurrentRequest == null)
            return;

        var ordered = m_ProgramRow.OrderedCards.Select(card => card.CardId).ToArray();
        var selected = m_ProgramRow.SelectedCardIds.ToArray();
        Main.Instance.Execute(new MoveCardsCommand(Main.Instance.CurrentRequest.RequestId, ordered, selected));
    }

    private void UpdateLabels()
    {
        var selectedIds = m_ProgramRow.SelectedCardIds.ToHashSet();
        var tapeSpace = 0;
        var handSpace = 0;

        foreach (var card in m_ProgramRow.OrderedCards)
        {
            if (selectedIds.Contains(card.CardId))
                tapeSpace += card.OccupiedSpace;
            else
                handSpace += card.OccupiedSpace;
        }

        m_TapeLabel.Text = $"{tapeSpace} / {Main.Instance.CoreLoop.Currency.TapeLength}";
        m_HandLabel.Text = $"{handSpace} / {Main.Instance.CoreLoop.Currency.HandSize}";
        m_Discard.Text = Main.Instance.CoreLoop.PatchDeck.Count.ToString();
        m_Discard.TooltipText = $"Discard {selectedIds.Count} instructions. Costs {Balancing.Instance.DiscardEnergyCost} each.";
    }

    private void RefreshDiscardCommand()
    {
        if (Main.Instance.CurrentRequest == null)
        {
            m_DiscardCommand = null;
            return;
        }

        m_DiscardCommand = new(Main.Instance.CurrentRequest.RequestId, m_ProgramRow.SelectedCardIds.ToArray());

        if (m_Discard != null)
            m_Discard.Disabled = m_DiscardCommand == null || !m_DiscardCommand.IsValid(Main.Instance.CoreLoop, out _);
    }

    private void OnSelectionChanged(CardControl[] cardControls)
    {
        RefreshDiscardCommand();
        UpdateLabels();
        SendMoveCommand();
    }

    private bool CanChangeSelection(CardControl cardControl, bool selected)
    {
        var selectedIds = m_ProgramRow.SelectedCardIds.ToHashSet();
        if (selected)
            selectedIds.Add(cardControl.Card.CardId);
        else
            selectedIds.Remove(cardControl.Card.CardId);

        var tapeSpace = 0;
        var handSpace = 0;

        foreach (var card in m_ProgramRow.OrderedCards)
        {
            if (selectedIds.Contains(card.CardId))
                tapeSpace += card.OccupiedSpace;
            else
                handSpace += card.OccupiedSpace;
        }

        return tapeSpace <= Main.Instance.CoreLoop.Currency.TapeLength && handSpace <= Main.Instance.CoreLoop.Currency.HandSize;
    }

    private void OnExecutePressed()
    {
        Main.Instance.Execute(m_RunProgramCommand);
    }

    private void OnDiscardPressed()
    {
        Main.Instance.Execute(m_DiscardCommand);
    }

    private void OnSortPressed()
    {
        var selectedIds = m_ProgramRow.SelectedCardIds.ToHashSet();
        var unselected = m_ProgramRow.OrderedCards.Where(card => !selectedIds.Contains(card.CardId)).ToList();
        var sortedUnselected = CardExtensions.SortForHand(unselected);
        var ordered = new List<Card>(m_ProgramRow.OrderedCards.Count);
        var unselectedIndex = 0;

        foreach (var card in m_ProgramRow.OrderedCards)
        {
            if (selectedIds.Contains(card.CardId))
            {
                ordered.Add(card);
                continue;
            }

            ordered.Add(sortedUnselected[unselectedIndex]);
            unselectedIndex += 1;
        }

        m_ProgramRow.Configure(ordered, GetTree().CreateTween(), false, false);
        m_ProgramRow.ApplySelection(selectedIds, true);
        OnOrderChanged();
    }

    public void Deactivate()
    {
    }

    public void EnableInputs()
    {
        m_RunProgramCommand ??= new(Main.Instance.CurrentRequest.RequestId);
        RefreshDiscardCommand();
        m_Sort.Disabled = false;
    }

    public void DisableInputs()
    {
        m_RunProgramCommand = null;
        m_DiscardCommand = null;
        m_Sort.Disabled = true;
    }

    public void Activate()
    {
    }

    public bool HandleResult(Result result, Tween tween)
    {
        switch (result)
        {
            case RunCardResult runCardResult:
            {
                m_ProgramRow.RunCard(runCardResult.Card, tween);
                RefreshDiscardCommand();
                UpdateLabels();
                return true;
            }
            case ProgramRowResult programRowResult:
            {
                m_ProgramRow.Configure(programRowResult.OrderedCards, tween, false, false);
                m_ProgramRow.ApplySelection(programRowResult.TapeCardIds, true);
                RefreshDiscardCommand();
                UpdateLabels();
                return true;
            }
            case ModifyCardResult modifyCardResult:
            {
                m_ProgramRow.ModifyCard(modifyCardResult.Card, modifyCardResult.Modifier, tween);
                UpdateLabels();
                return true;
            }
            case HandResult:
            case TapeResult:
            {
                UpdateLabels();
                return true;
            }
        }

        return false;
    }

    public override void _Process(double delta)
    {
        if (m_Execute != null)
        {
            m_Execute.Disabled = m_RunProgramCommand == null;
            var lastRun = m_RunProgramCommand?.Preview(Main.Instance.CoreLoop).Any(r => r is RunPhaseResult { NewRunPhase: ERunPhase.Scoring }) ?? false;
            if (lastRun)
            {
                m_FlameBackground.Visible = true;
                m_Execute.TooltipText = "Execute last program";
            }
            else
            {
                m_FlameBackground.Visible = false;
                m_Execute.TooltipText = "Execute";
            }
        }
    }

    public void Configure(Tween tween)
    {
        var coreLoop = Main.Instance.CoreLoop;
        var ordered = coreLoop.ProgramRow.ToList();
        m_ProgramRow.Configure(ordered, tween, false, false);
        m_ProgramRow.ApplySelection(coreLoop.TapeCardIds.ToArray(), true);
        m_RunProgramCommand = new(Main.Instance.CurrentRequest.RequestId);
        RefreshDiscardCommand();
        UpdateLabels();
    }

    private RunProgramCommand m_RunProgramCommand;
    private DiscardCommand m_DiscardCommand;

    private CardRow m_ProgramRow;
    private Button m_Execute;
    private Button m_Discard;
    private Button m_Sort;
    private Label m_TapeLabel;
    private Label m_HandLabel;
    private Node2D m_FlameBackground;
}