using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;
using System.Windows.Media;

namespace AxCopilot.Views;

internal sealed partial class PlanViewerWindow
{
    // ════════════════════════════════════════════════════════════
    // 단계 목록 렌더링
    // ════════════════════════════════════════════════════════════

    private void RenderSteps()
    {
        _stepsPanel.Children.Clear();

        var primaryText   = Application.Current.TryFindResource("PrimaryText") as Brush ?? Brushes.White;
        var secondaryText = Application.Current.TryFindResource("SecondaryText") as Brush ?? Brushes.Gray;
        var accentBrush   = Application.Current.TryFindResource("AccentColor") as Brush
                            ?? new SolidColorBrush(Color.FromRgb(0x4B, 0x5E, 0xFC));
        var itemBg  = Application.Current.TryFindResource("ItemBackground") as Brush
                      ?? new SolidColorBrush(Color.FromRgb(0x2A, 0x2B, 0x40));
        var hoverBg = Application.Current.TryFindResource("ItemHoverBackground") as Brush
                      ?? new SolidColorBrush(Color.FromArgb(0x18, 0xFF, 0xFF, 0xFF));

        var canEdit = !_isExecuting && _currentStep < 0; // 승인 대기 중에만 편집/순서변경 가능

        for (int i = 0; i < _steps.Count; i++)
        {
            var step       = _steps[i];
            var capturedIdx = i;
            var isComplete = i < _currentStep;
            var isCurrent  = i == _currentStep;
            var isPending  = i > _currentStep;
            var isExpanded = _expandedSteps.Contains(i);

            // ─ 카드 Border ─
            var card = new Border
            {
                CornerRadius    = new CornerRadius(10),
                Padding         = new Thickness(10, 7, 10, 7),
                Margin          = new Thickness(0, 0, 0, 5),
                Background      = isCurrent
                    ? new SolidColorBrush(Color.FromArgb(0x18,
                        ((SolidColorBrush)accentBrush).Color.R,
                        ((SolidColorBrush)accentBrush).Color.G,
                        ((SolidColorBrush)accentBrush).Color.B))
                    : itemBg,
                BorderBrush     = isCurrent ? accentBrush : Brushes.Transparent,
                BorderThickness = new Thickness(isCurrent ? 1.5 : 0),
                AllowDrop       = canEdit,
            };

            // 열기/닫기 토글 — 텍스트 또는 배경 클릭
            card.Cursor = Cursors.Hand;
            card.MouseLeftButtonUp += (s, e) =>
            {
                // 드래그 직후 클릭이 발생하는 경우 무시
                if (e.OriginalSource is Border src && src.Tag?.ToString() == "DragHandle") return;
                if (_expandedSteps.Contains(capturedIdx)) _expandedSteps.Remove(capturedIdx);
                else _expandedSteps.Add(capturedIdx);
                RenderSteps();
            };

            // ─ 카드 Grid: [drag?][badge][*text][chevron][edit?] ─
            var cardGrid = new Grid();
            int badgeCol  = canEdit ? 1 : 0;
            int textCol   = canEdit ? 2 : 1;
            int chevCol   = canEdit ? 3 : 2;
            int editCol   = canEdit ? 4 : -1;

            if (canEdit)
                cardGrid.ColumnDefinitions.Add(new ColumnDefinition { Width = GridLength.Auto });       // drag
            cardGrid.ColumnDefinitions.Add(new ColumnDefinition { Width = GridLength.Auto });           // badge
            cardGrid.ColumnDefinitions.Add(new ColumnDefinition { Width = new GridLength(1, GridUnitType.Star) }); // text
            cardGrid.ColumnDefinitions.Add(new ColumnDefinition { Width = GridLength.Auto });           // chevron
            if (canEdit)
                cardGrid.ColumnDefinitions.Add(new ColumnDefinition { Width = GridLength.Auto });       // edit btns

            // ── 드래그 핸들 (편집 모드 전용) ──
            if (canEdit)
            {
                var dimColor = Color.FromArgb(0x55, 0x80, 0x80, 0x80);
                var dimBrush = new SolidColorBrush(dimColor);
                var dragHandle = new Border
                {
                    Tag = "DragHandle",
                    Width = 20, Cursor = Cursors.SizeAll,
                    Background = Brushes.Transparent,
                    Margin = new Thickness(0, 0, 6, 0),
                    VerticalAlignment = VerticalAlignment.Center,
                    Child = new TextBlock
                    {
                        Text = "\uE8FD", // Sort/Lines 아이콘 (드래그 핸들)
                        FontFamily = ThemeResourceHelper.SegoeMdl2,
                        FontSize = 11,
                        Foreground = dimBrush,
                        HorizontalAlignment = HorizontalAlignment.Center,
                        VerticalAlignment = VerticalAlignment.Center,
                    },
                };
                dragHandle.MouseEnter += (s, _) =>
                    ((TextBlock)((Border)s).Child).Foreground = secondaryText;
                dragHandle.MouseLeave += (s, _) =>
                    ((TextBlock)((Border)s).Child).Foreground = dimBrush;

                // 드래그 시작 — 마우스 눌림 위치 기록
                dragHandle.PreviewMouseLeftButtonDown += (s, e) =>
                {
                    _dragSourceIndex = capturedIdx;
                    _dragStartPoint  = e.GetPosition(_stepsPanel);
                    e.Handled = true; // 카드 클릭(expand) 이벤트 방지
                };
                // 충분히 움직이면 DragDrop 시작
                dragHandle.PreviewMouseMove += (s, e) =>
                {
                    if (_dragSourceIndex < 0 || e.LeftButton != MouseButtonState.Pressed) return;
                    var cur = e.GetPosition(_stepsPanel);
                    if (Math.Abs(cur.X - _dragStartPoint.X) > SystemParameters.MinimumHorizontalDragDistance ||
                        Math.Abs(cur.Y - _dragStartPoint.Y) > SystemParameters.MinimumVerticalDragDistance)
                    {
                        int idx = _dragSourceIndex;
                        _dragSourceIndex = -1;
                        DragDrop.DoDragDrop((DependencyObject)s,
                            new DataObject(DragDataFormat, idx), DragDropEffects.Move);
                        // DoDragDrop 완료 후 비주얼 정리
                        Dispatcher.InvokeAsync(RenderSteps);
                    }
                };
                dragHandle.PreviewMouseLeftButtonUp += (_, _) => _dragSourceIndex = -1;

                Grid.SetColumn(dragHandle, 0);
                cardGrid.Children.Add(dragHandle);

                // ── 카드 Drop 이벤트 ──
                card.DragOver += (s, e) =>
                {
                    if (!e.Data.GetDataPresent(DragDataFormat)) return;
                    int src = (int)e.Data.GetData(DragDataFormat);
                    if (src != capturedIdx)
                    {
                        ((Border)s).BorderBrush     = accentBrush;
                        ((Border)s).BorderThickness = new Thickness(1.5);
                        e.Effects = DragDropEffects.Move;
                    }
                    else e.Effects = DragDropEffects.None;
                    e.Handled = true;
                };
                card.DragLeave += (s, _) =>
                {
                    bool isCurr = _currentStep == capturedIdx;
                    ((Border)s).BorderBrush     = isCurr ? accentBrush : Brushes.Transparent;
                    ((Border)s).BorderThickness = new Thickness(isCurr ? 1.5 : 0);
                };
                card.Drop += (s, e) =>
                {
                    if (!e.Data.GetDataPresent(DragDataFormat)) { e.Handled = true; return; }
                    int srcIdx = (int)e.Data.GetData(DragDataFormat);
                    int dstIdx = capturedIdx;
                    if (srcIdx != dstIdx && srcIdx >= 0 && srcIdx < _steps.Count)
                    {
                        var item = _steps[srcIdx];
                        _steps.RemoveAt(srcIdx);
                        // srcIdx < dstIdx 이면 제거 후 인덱스가 1 감소
                        int insertAt = srcIdx < dstIdx ? dstIdx - 1 : dstIdx;
                        _steps.Insert(insertAt, item);
                        _expandedSteps.Clear();
                        RenderSteps();
                    }
                    e.Handled = true;
                };
            }

            // ── 상태 배지 ──
            UIElement badge;
            if (isComplete)
            {
                badge = new TextBlock
                {
                    Text = "\uE73E", FontFamily = ThemeResourceHelper.SegoeMdl2,
                    FontSize = 13, Foreground = new SolidColorBrush(Color.FromRgb(0x10, 0xB9, 0x81)),
                    VerticalAlignment = VerticalAlignment.Center, Margin = new Thickness(0, 0, 10, 0),
                    Width = 20, TextAlignment = TextAlignment.Center,
                };
            }
            else if (isCurrent)
            {
                badge = new TextBlock
                {
                    Text = "\uE768", FontFamily = ThemeResourceHelper.SegoeMdl2,
                    FontSize = 13, Foreground = accentBrush,
                    VerticalAlignment = VerticalAlignment.Center, Margin = new Thickness(0, 0, 10, 0),
                    Width = 20, TextAlignment = TextAlignment.Center,
                };
            }
            else
            {
                badge = new Border
                {
                    Width = 22, Height = 22, CornerRadius = new CornerRadius(11),
                    Background = new SolidColorBrush(Color.FromArgb(0x25, 0x80, 0x80, 0x80)),
                    Margin = new Thickness(0, 0, 10, 0), VerticalAlignment = VerticalAlignment.Center,
                    Child = new TextBlock
                    {
                        Text = $"{i + 1}", FontSize = 11, Foreground = secondaryText,
                        FontWeight = FontWeights.SemiBold,
                        HorizontalAlignment = HorizontalAlignment.Center,
                        VerticalAlignment = VerticalAlignment.Center,
                    },
                };
            }
            Grid.SetColumn(badge, badgeCol);
            cardGrid.Children.Add(badge);

            // ── 단계 텍스트 ──
            var textBlock = new TextBlock
            {
                Text            = step,
                FontSize        = 13,
                Foreground      = isComplete ? secondaryText : primaryText,
                VerticalAlignment = VerticalAlignment.Center,
                Opacity         = isPending && _isExecuting ? 0.6 : 1.0,
                TextDecorations = isComplete ? TextDecorations.Strikethrough : null,
                Margin          = new Thickness(0, 0, 4, 0),
            };
            if (isExpanded)
            {
                textBlock.TextWrapping = TextWrapping.Wrap;
                textBlock.TextTrimming = TextTrimming.None;
            }
            else
            {
                textBlock.TextWrapping = TextWrapping.NoWrap;
                textBlock.TextTrimming = TextTrimming.CharacterEllipsis;
                textBlock.ToolTip      = step; // 접힌 상태: 호버 시 전체 텍스트 툴팁
            }
            Grid.SetColumn(textBlock, textCol);
            cardGrid.Children.Add(textBlock);

            // ── 펼침/접힘 Chevron ──
            var chevron = new Border
            {
                Width = 22, Height = 22, CornerRadius = new CornerRadius(4),
                Background = Brushes.Transparent, Cursor = Cursors.Hand,
                VerticalAlignment = VerticalAlignment.Center,
                Margin = new Thickness(0, 0, canEdit ? 4 : 0, 0),
                Child = new TextBlock
                {
                    Text = isExpanded ? "\uE70E" : "\uE70D", // ChevronUp / ChevronDown
                    FontFamily = ThemeResourceHelper.SegoeMdl2,
                    FontSize   = 9,
                    Foreground = new SolidColorBrush(Color.FromArgb(0x70, 0x80, 0x80, 0x80)),
                    HorizontalAlignment = HorizontalAlignment.Center,
                    VerticalAlignment   = VerticalAlignment.Center,
                },
            };
            chevron.MouseEnter += (s, _) => ((Border)s).Background = hoverBg;
            chevron.MouseLeave += (s, _) => ((Border)s).Background = Brushes.Transparent;
            chevron.MouseLeftButtonUp += (_, e) =>
            {
                if (_expandedSteps.Contains(capturedIdx)) _expandedSteps.Remove(capturedIdx);
                else _expandedSteps.Add(capturedIdx);
                RenderSteps();
                e.Handled = true;
            };
            Grid.SetColumn(chevron, chevCol);
            cardGrid.Children.Add(chevron);

            // ── 편집 버튼 (위/아래/편집/삭제) ──
            if (canEdit)
            {
                var editBtnPanel = new StackPanel
                {
                    Orientation = Orientation.Horizontal,
                    VerticalAlignment = VerticalAlignment.Center,
                    Margin = new Thickness(2, 0, 0, 0),
                };

                if (i > 0)
                {
                    var upBtn = CreateMiniButton("\uE70E", secondaryText, hoverBg);
                    upBtn.ToolTip = "위로 이동";
                    upBtn.MouseLeftButtonUp += (_, e) => { SwapSteps(capturedIdx, capturedIdx - 1); e.Handled = true; };
                    editBtnPanel.Children.Add(upBtn);
                }
                if (i < _steps.Count - 1)
                {
                    var downBtn = CreateMiniButton("\uE70D", secondaryText, hoverBg);
                    downBtn.ToolTip = "아래로 이동";
                    downBtn.MouseLeftButtonUp += (_, e) => { SwapSteps(capturedIdx, capturedIdx + 1); e.Handled = true; };
                    editBtnPanel.Children.Add(downBtn);
                }

                var editBtn = CreateMiniButton("\uE70F", accentBrush, hoverBg);
                editBtn.ToolTip = "편집";
                editBtn.MouseLeftButtonUp += (_, e) => { EditStep(capturedIdx); e.Handled = true; };
                editBtnPanel.Children.Add(editBtn);

                var delBtn = CreateMiniButton("\uE74D", new SolidColorBrush(Color.FromRgb(0xDC, 0x26, 0x26)), hoverBg);
                delBtn.ToolTip = "삭제";
                delBtn.MouseLeftButtonUp += (_, e) =>
                {
                    if (_steps.Count > 1)
                    {
                        _steps.RemoveAt(capturedIdx);
                        _expandedSteps.Remove(capturedIdx);
                        RenderSteps();
                    }
                    e.Handled = true;
                };
                editBtnPanel.Children.Add(delBtn);

                Grid.SetColumn(editBtnPanel, editCol);
                cardGrid.Children.Add(editBtnPanel);
            }

            card.Child = cardGrid;
            _stepsPanel.Children.Add(card);
        }

        // ── 단계 추가 버튼 (편집 모드) ──
        if (canEdit)
        {
            var st2  = Application.Current.TryFindResource("SecondaryText") as Brush ?? Brushes.Gray;
            var hb2  = Application.Current.TryFindResource("ItemHoverBackground") as Brush
                       ?? new SolidColorBrush(Color.FromArgb(0x18, 0xFF, 0xFF, 0xFF));
            var addBtn = new Border
            {
                CornerRadius    = new CornerRadius(10),
                Padding         = new Thickness(14, 8, 14, 8),
                Margin          = new Thickness(0, 4, 0, 0),
                Background      = Brushes.Transparent,
                BorderBrush     = new SolidColorBrush(Color.FromArgb(0x30, 0x80, 0x80, 0x80)),
                BorderThickness = new Thickness(1),
                Cursor          = Cursors.Hand,
            };
            var addSp = new StackPanel { Orientation = Orientation.Horizontal, HorizontalAlignment = HorizontalAlignment.Center };
            addSp.Children.Add(new TextBlock
            {
                Text = "\uE710", FontFamily = ThemeResourceHelper.SegoeMdl2,
                FontSize = 12, Foreground = st2,
                VerticalAlignment = VerticalAlignment.Center, Margin = new Thickness(0, 0, 6, 0),
            });
            addSp.Children.Add(new TextBlock { Text = "단계 추가", FontSize = 12, Foreground = st2 });
            addBtn.Child = addSp;
            addBtn.MouseEnter += (s, _) => ((Border)s).Background = hb2;
            addBtn.MouseLeave += (s, _) => ((Border)s).Background = Brushes.Transparent;
            addBtn.MouseLeftButtonUp += (_, _) =>
            {
                _steps.Add("새 단계");
                RenderSteps();
                EditStep(_steps.Count - 1);
            };
            _stepsPanel.Children.Add(addBtn);
        }

        // 현재 단계로 자동 스크롤
        if (_currentStep >= 0 && _stepsPanel.Children.Count > _currentStep)
        {
            _stepsPanel.UpdateLayout();
            var target = (FrameworkElement)_stepsPanel.Children[Math.Min(_currentStep, _stepsPanel.Children.Count - 1)];
            target.BringIntoView();
        }
    }

    // ════════════════════════════════════════════════════════════
    // 단계 편집 / 교환
    // ════════════════════════════════════════════════════════════

    private void SwapSteps(int a, int b)
    {
        if (a < 0 || b < 0 || a >= _steps.Count || b >= _steps.Count) return;
        (_steps[a], _steps[b]) = (_steps[b], _steps[a]);
        RenderSteps();
    }

    private void EditStep(int index)
    {
        if (index < 0 || index >= _steps.Count) return;
        var primaryText = Application.Current.TryFindResource("PrimaryText") as Brush ?? Brushes.White;
        var itemBg      = Application.Current.TryFindResource("ItemBackground") as Brush
                          ?? new SolidColorBrush(Color.FromRgb(0x2A, 0x2B, 0x40));
        var accentBrush = Application.Current.TryFindResource("AccentColor") as Brush
                          ?? new SolidColorBrush(Color.FromRgb(0x4B, 0x5E, 0xFC));

        if (index >= _stepsPanel.Children.Count) return;

        var editCard = new Border
        {
            CornerRadius    = new CornerRadius(10),
            Padding         = new Thickness(10, 8, 10, 8),
            Margin          = new Thickness(0, 0, 0, 5),
            Background      = itemBg,
            BorderBrush     = accentBrush,
            BorderThickness = new Thickness(1.5),
        };

        var textBox = new TextBox
        {
            Text             = _steps[index],
            FontSize         = 13,
            Background       = Brushes.Transparent,
            Foreground       = primaryText,
            CaretBrush       = primaryText,
            BorderThickness  = new Thickness(0),
            AcceptsReturn    = false,
            TextWrapping     = TextWrapping.Wrap,
            Padding          = new Thickness(4),
        };

        var capturedIdx = index;
        textBox.KeyDown += (_, e) =>
        {
            if (e.Key == Key.Enter)  { _steps[capturedIdx] = textBox.Text.Trim(); RenderSteps(); e.Handled = true; }
            if (e.Key == Key.Escape) { RenderSteps(); e.Handled = true; }
        };
        textBox.LostFocus += (_, _) => { _steps[capturedIdx] = textBox.Text.Trim(); RenderSteps(); };

        editCard.Child = textBox;
        _stepsPanel.Children[index] = editCard;
        textBox.Focus();
        textBox.SelectAll();
    }
}