using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;
using System.Windows.Media;
using AxCopilot.Models;
using AxCopilot.Services;

namespace AxCopilot.Views;

public partial class ChatWindow
{
    // 레이아웃 재계산 억제용 캐시: 동일한 높이면 WPF measure/arrange 생략
    private double _cachedInputBoxHeight = -1;
    private int _cachedInputBoxMaxLines = -1;

    private void UpdateInputBoxHeight()
    {
        if (InputBox == null)
            return;

        var text = InputBox.Text ?? string.Empty;
        var explicitLineCount = 1 + text.Count(ch => ch == '\n');
        var displayMode = (_settings.Settings.Llm.AgentUiExpressionLevel ?? "balanced").Trim().ToLowerInvariant();
        if (displayMode is not ("rich" or "balanced" or "simple"))
            displayMode = "balanced";

        var maxLines = displayMode switch
        {
            "rich" => 6,
            "simple" => 4,
            _ => 5,
        };
        const double baseHeight = 42;
        const double lineStep = 22;
        var visibleLines = Math.Clamp(explicitLineCount, 1, maxLines);
        var targetHeight = baseHeight + ((visibleLines - 1) * lineStep);
        var needsScroll = explicitLineCount > maxLines;

        // 값이 바뀐 경우에만 WPF 속성 쓰기 (매 키입력마다 레이아웃 통과 방지)
        if (Math.Abs(targetHeight - _cachedInputBoxHeight) < 0.5 && maxLines == _cachedInputBoxMaxLines)
            return;

        _cachedInputBoxHeight = targetHeight;
        _cachedInputBoxMaxLines = maxLines;

        InputBox.MinLines = 1;
        InputBox.MaxLines = maxLines;
        InputBox.Height = targetHeight;
        InputBox.VerticalScrollBarVisibility = needsScroll
            ? ScrollBarVisibility.Auto
            : ScrollBarVisibility.Disabled;
    }

    private string BuildComposerDraftText()
    {
        var rawText = InputBox?.Text?.Trim() ?? "";
        return _slashPalette.ActiveCommand != null
            ? (_slashPalette.ActiveCommand + " " + rawText).Trim()
            : rawText;
    }

    private static string InferDraftKind(string text, string? explicitKind = null)
    {
        var trimmed = text?.Trim() ?? "";
        var requestedKind = explicitKind?.Trim().ToLowerInvariant();

        if (requestedKind is "followup" or "steering")
            return requestedKind;

        if (trimmed.StartsWith("/", StringComparison.OrdinalIgnoreCase))
            return "command";

        if (requestedKind is "direct" or "message")
            return requestedKind;

        if (trimmed.StartsWith("steer:", StringComparison.OrdinalIgnoreCase) ||
            trimmed.StartsWith("@steer ", StringComparison.OrdinalIgnoreCase) ||
            trimmed.StartsWith("조정:", StringComparison.OrdinalIgnoreCase))
            return "steering";

        return "message";
    }

    private void QueueComposerDraft(string priority = "next", string? explicitKind = null, bool startImmediatelyWhenIdle = true)
    {
        if (InputBox == null)
            return;

        var text = BuildComposerDraftText();
        if (string.IsNullOrWhiteSpace(text))
            return;

        // 현재 탭이 스트리밍 중일 때만 우선순위를 "next"로 낮춤 — 다른 탭 스트리밍은 무관
        if (_streamingTabs.Contains(_activeTab) && string.Equals(priority, "now", StringComparison.OrdinalIgnoreCase))
            priority = "next";

        HideSlashChip(restoreText: false);
        ClearPromptCardPlaceholder();

        var queuedItem = EnqueueDraftRequest(text, priority, explicitKind);

        InputBox.Clear();
        InputBox.Focus();
        UpdateInputBoxHeight();
        RefreshDraftQueueUi();

        if (queuedItem == null)
            return;

        if (!_streamingTabs.Contains(_activeTab) && startImmediatelyWhenIdle)
        {
            StartNextQueuedDraftIfAny(queuedItem.Id);
            return;
        }

        var runningTab = _streamRunTab;
        var runningLabel = runningTab switch
        {
            "Cowork" => "코워크",
            "Code" => "코드",
            "Chat" => "채팅",
            _ => runningTab ?? "다른 탭",
        };
        var suffix = !string.IsNullOrEmpty(runningTab) && !string.Equals(runningTab, _activeTab, StringComparison.OrdinalIgnoreCase)
            ? $" ({runningLabel} 실행 완료 후 자동 실행)"
            : " (실행 완료 후 자동 실행)";
        var toast = queuedItem.Kind switch
        {
            "command" => "명령이 대기열에 추가되었습니다." + suffix,
            "direct" => "직접 실행 요청이 대기열에 추가되었습니다." + suffix,
            "steering" => "조정 요청이 대기열에 추가되었습니다." + suffix,
            "followup" => "후속 작업이 대기열에 추가되었습니다." + suffix,
            _ => "메시지가 대기열에 추가되었습니다." + suffix,
        };
        ShowToast(toast);
    }

    private void RefreshDraftQueueUi()
    {
        if (DraftPreviewCard == null || DraftPreviewText == null || DraftQueuePanel == null || BtnDraftEnqueue == null)
            return;

        lock (_convLock)
        {
            var session = ChatSession;
            if (session != null)
                _draftQueueProcessor.PromoteReadyBlockedItems(session, _activeTab, _storage);
        }

        var items = _appState.GetDraftQueueItems(_activeTab);

        DraftPreviewCard.Visibility = Visibility.Collapsed;
        BtnDraftEnqueue.IsEnabled = false;
        DraftPreviewText.Text = string.Empty;

        RebuildDraftQueuePanel(items);
    }

    // --- Queue panel (Codex style) ---

    private void RebuildDraftQueuePanel(IReadOnlyList<DraftQueueItem> items)
    {
        if (DraftQueuePanel == null)
            return;

        DraftQueuePanel.Children.Clear();

        var visibleItems = items
            .Where(x => !string.Equals(x.State, "completed", StringComparison.OrdinalIgnoreCase)  // 완료 항목 제거
                     && !string.Equals(x.State, "running",   StringComparison.OrdinalIgnoreCase)) // 수행 중인 항목은 채팅창에서 이미 표시됨
            .OrderBy(GetDraftStateRank)
            .ThenBy(GetDraftPriorityRank)
            .ThenBy(x => x.CreatedAt)
            .ToList();

        if (visibleItems.Count == 0)
        {
            DraftQueuePanel.Visibility = Visibility.Collapsed;
            return;
        }

        DraftQueuePanel.Visibility = Visibility.Visible;

        // 단일 통합 컨테이너
        var containerBorder = new Border
        {
            Background = TryFindResource("ItemBackground") as Brush ?? BrushFromHex("#1E1E2A"),
            BorderBrush = TryFindResource("BorderColor") as Brush ?? BrushFromHex("#3A3A4A"),
            BorderThickness = new Thickness(1),
            CornerRadius = new CornerRadius(10),
            Margin = new Thickness(0, 0, 0, 4),
        };

        var innerStack = new StackPanel();
        containerBorder.Child = innerStack;

        for (int i = 0; i < visibleItems.Count; i++)
        {
            innerStack.Children.Add(CreateDraftQueueRow(visibleItems[i]));

            // 구분선 (마지막 항목 제외)
            if (i < visibleItems.Count - 1)
            {
                innerStack.Children.Add(new Border
                {
                    Height = 1,
                    Background = TryFindResource("BorderColor") as Brush ?? BrushFromHex("#2E2E3E"),
                    Margin = new Thickness(10, 0, 10, 0),
                });
            }
        }

        DraftQueuePanel.Children.Add(containerBorder);

        // 실패 항목 정리 버튼 (실패만 — 완료는 자동 제거됨)
        var summary = _appState.GetDraftQueueSummary(_activeTab);
        if (summary.FailedCount > 0)
        {
            var failBtn = CreateQueueFooterButton($"실패 정리 ({summary.FailedCount})", ClearFailedDrafts);
            DraftQueuePanel.Children.Add(failBtn);
        }
    }

    // --- Codex-style row ---

    private Border CreateDraftQueueRow(DraftQueueItem item)
    {
        var isRunning = string.Equals(item.State, "running", StringComparison.OrdinalIgnoreCase);
        var isFailed = string.Equals(item.State, "failed", StringComparison.OrdinalIgnoreCase);
        var primaryText = TryFindResource("PrimaryText") as Brush ?? BrushFromHex("#E5E5EA");
        var secondaryText = TryFindResource("SecondaryText") as Brush ?? BrushFromHex("#8E8E9A");

        var row = new Border
        {
            Padding = new Thickness(10, 7, 8, 7),
        };

        var grid = new Grid();
        grid.ColumnDefinitions.Add(new ColumnDefinition { Width = GridLength.Auto });     // state icon
        grid.ColumnDefinitions.Add(new ColumnDefinition { Width = new GridLength(1, GridUnitType.Star) }); // text
        grid.ColumnDefinitions.Add(new ColumnDefinition { Width = GridLength.Auto });     // actions
        row.Child = grid;

        // State icon
        var stateIcon = new TextBlock
        {
            Text = GetDraftStateIcon(item),
            FontFamily = new FontFamily("Segoe MDL2 Assets"),
            FontSize = 11,
            Foreground = GetDraftStateIconBrush(item),
            VerticalAlignment = VerticalAlignment.Center,
            Margin = new Thickness(0, 0, 8, 0),
            Width = 14,
        };
        Grid.SetColumn(stateIcon, 0);
        grid.Children.Add(stateIcon);

        // Message text
        var msgText = new TextBlock
        {
            Text = item.Text,
            FontSize = 12,
            Foreground = isFailed ? (TryFindResource("SecondaryText") as Brush ?? BrushFromHex("#8E8E9A")) : primaryText,
            TextTrimming = TextTrimming.CharacterEllipsis,
            VerticalAlignment = VerticalAlignment.Center,
            Margin = new Thickness(0, 0, 8, 0),
        };
        Grid.SetColumn(msgText, 1);
        grid.Children.Add(msgText);

        // Right actions
        var actions = new StackPanel
        {
            Orientation = Orientation.Horizontal,
            VerticalAlignment = VerticalAlignment.Center,
        };
        Grid.SetColumn(actions, 2);
        grid.Children.Add(actions);

        if (!isRunning)
        {
            // Kind chip (↪ 조정 style)
            actions.Children.Add(CreateKindChip(item, secondaryText));
        }

        if (!isRunning && !isFailed)
        {
            // Run now button
            actions.Children.Add(CreateRowIconButton("\uE768", "지금 실행", () => QueueDraftForImmediateRun(item.Id)));
        }

        if (!isRunning)
        {
            // Edit button
            actions.Children.Add(CreateRowIconButton("\uE70F", "편집", () => PopDraftToEditor(item.Id)));
        }

        // Delete
        actions.Children.Add(CreateRowIconButton("\uE74D", isRunning ? "취소" : "삭제", () => RemoveDraftFromQueue(item.Id)));

        return row;
    }

    // Kind chip on the right — "↪ 조정" style
    private Border CreateKindChip(DraftQueueItem item, Brush defaultForeground)
    {
        var (kindIcon, kindLabel) = GetDraftKindChipContent(item);
        var foreground = GetDraftKindChipColor(item);

        return new Border
        {
            BorderBrush = foreground,
            BorderThickness = new Thickness(1),
            CornerRadius = new CornerRadius(5),
            Padding = new Thickness(5, 2, 6, 2),
            Margin = new Thickness(0, 0, 4, 0),
            VerticalAlignment = VerticalAlignment.Center,
            Child = new StackPanel
            {
                Orientation = Orientation.Horizontal,
                Children =
                {
                    new TextBlock
                    {
                        Text = kindIcon,
                        FontFamily = new FontFamily("Segoe MDL2 Assets"),
                        FontSize = 10,
                        Foreground = foreground,
                        VerticalAlignment = VerticalAlignment.Center,
                        Margin = new Thickness(0, 0, 3, 0),
                    },
                    new TextBlock
                    {
                        Text = kindLabel,
                        FontSize = 10.5,
                        Foreground = foreground,
                        VerticalAlignment = VerticalAlignment.Center,
                    },
                }
            }
        };
    }

    // Row icon button — flat, no border
    private Button CreateRowIconButton(string icon, string tooltip, Action onClick)
    {
        var btn = new Button
        {
            Content = new TextBlock
            {
                Text = icon,
                FontFamily = new FontFamily("Segoe MDL2 Assets"),
                FontSize = 11,
                VerticalAlignment = VerticalAlignment.Center,
                HorizontalAlignment = HorizontalAlignment.Center,
            },
            Width = 24,
            Height = 24,
            Padding = new Thickness(0),
            Background = Brushes.Transparent,
            BorderThickness = new Thickness(0),
            Foreground = TryFindResource("SecondaryText") as Brush ?? BrushFromHex("#8E8E9A"),
            Cursor = Cursors.Hand,
            ToolTip = tooltip,
        };
        btn.Click += (_, _) => onClick();
        return btn;
    }

    // Footer button (failed clear)
    private Button CreateQueueFooterButton(string label, Action onClick)
    {
        var btn = new Button
        {
            Content = label,
            Margin = new Thickness(0, 2, 0, 0),
            Padding = new Thickness(10, 4, 10, 4),
            FontSize = 11,
            Background = Brushes.Transparent,
            BorderBrush = TryFindResource("BorderColor") as Brush ?? BrushFromHex("#3A3A4A"),
            BorderThickness = new Thickness(1),
            Foreground = TryFindResource("SecondaryText") as Brush ?? BrushFromHex("#8E8E9A"),
            HorizontalAlignment = HorizontalAlignment.Left,
            Cursor = Cursors.Hand,
        };
        btn.Click += (_, _) => onClick();
        return btn;
    }

    // Pop queued draft back into the InputBox for editing
    private void PopDraftToEditor(string draftId)
    {
        string? text = null;
        lock (_convLock)
        {
            var session = ChatSession;
            if (session != null)
            {
                var item = session.GetDraftQueueItems(_activeTab)
                    .FirstOrDefault(x => string.Equals(x.Id, draftId, StringComparison.OrdinalIgnoreCase));
                if (item != null)
                {
                    text = item.Text;
                    if (session.RemoveDraft(_activeTab, draftId, _storage))
                        _currentConversation = session.CurrentConversation ?? _currentConversation;
                }
            }
        }

        if (InputBox != null && text != null)
        {
            InputBox.Text = text;
            InputBox.CaretIndex = text.Length;
            InputBox.Focus();
            UpdateInputBoxHeight();
        }

        RefreshDraftQueueUi();
    }

    // --- Icon-only button (kept for compatibility) ---
    private Button CreateIconButton(string icon, string tooltip, Action onClick)
        => CreateRowIconButton(icon, tooltip, onClick);

    // --- Ranking helpers ---

    private static int GetDraftStateRank(DraftQueueItem item)
        => string.Equals(item.State, "running", StringComparison.OrdinalIgnoreCase) ? 0
            : IsDraftBlocked(item) ? 1
            : string.Equals(item.State, "queued", StringComparison.OrdinalIgnoreCase) ? 2
            : string.Equals(item.State, "failed", StringComparison.OrdinalIgnoreCase) ? 3
            : 4;

    private static int GetDraftPriorityRank(DraftQueueItem item)
        => item.Priority?.ToLowerInvariant() switch
        {
            "now" => 0,
            "next" => 1,
            _ => 2,
        };

    // --- State icon ---

    private static string GetDraftStateIcon(DraftQueueItem item)
    {
        if (IsDraftBlocked(item)) return "\uE9F5"; // 시계
        return item.State?.ToLowerInvariant() switch
        {
            "running"   => "\uE895", // 회전 (재생 아이콘)
            "failed"    => "\uE783", // 경고
            "completed" => "\uE73E", // 체크
            _           => "\uE76C", // 대기 점
        };
    }

    private Brush GetDraftStateIconBrush(DraftQueueItem item)
    {
        if (IsDraftBlocked(item)) return BrushFromHex("#C2410C");
        return item.State?.ToLowerInvariant() switch
        {
            "running"   => TryFindResource("AccentColor") as Brush ?? BrushFromHex("#5B8AF5"),
            "failed"    => BrushFromHex("#DC2626"),
            "completed" => BrushFromHex("#16A34A"),
            _           => TryFindResource("SecondaryText") as Brush ?? BrushFromHex("#8E8E9A"),
        };
    }

    // --- Kind chip ---

    private static (string Icon, string Label) GetDraftKindChipContent(DraftQueueItem item)
        => item.Kind?.ToLowerInvariant() switch
        {
            "followup" => ("\uE8A5", "후속"),
            "steering" => ("\uE7C3", "조정"),
            "command"  => ("\uE756", "명령"),
            "direct"   => ("\uE8A7", "직접"),
            _          => ("\uE8BD", "메시지"),
        };

    private Brush GetDraftKindChipColor(DraftQueueItem item)
        => item.Kind?.ToLowerInvariant() switch
        {
            "followup" => BrushFromHex("#0F766E"),
            "steering" => BrushFromHex("#B45309"),
            "command"  => BrushFromHex("#7C3AED"),
            "direct"   => BrushFromHex("#2563EB"),
            _          => TryFindResource("SecondaryText") as Brush ?? BrushFromHex("#6B7280"),
        };

    // --- Legacy helpers (used by other partial classes) ---

    private static string GetDraftKindLabel(DraftQueueItem item)
        => item.Kind?.ToLowerInvariant() switch
        {
            "followup" => "후속",
            "steering" => "조정",
            "command"  => "명령",
            "direct"   => "직접",
            _ => "메시지",
        };

    private static string GetDraftStateLabel(DraftQueueItem item)
        => IsDraftBlocked(item) ? "재시도 대기"
        : item.State?.ToLowerInvariant() switch
        {
            "running"   => "실행 중",
            "failed"    => "실패",
            "completed" => "완료",
            _           => "대기",
        };

    private (Brush Background, Brush Border, Brush Foreground) GetDraftStateBadgeColors(DraftQueueItem item)
        => IsDraftBlocked(item)
            ? (BrushFromHex("#FFF7ED"), BrushFromHex("#FDBA74"), BrushFromHex("#C2410C"))
            : item.State?.ToLowerInvariant() switch
            {
                "running"   => (BrushFromHex("#EFF6FF"), BrushFromHex("#BFDBFE"), BrushFromHex("#1D4ED8")),
                "failed"    => (BrushFromHex("#FEF2F2"), BrushFromHex("#FECACA"), BrushFromHex("#991B1B")),
                "completed" => (BrushFromHex("#ECFDF5"), BrushFromHex("#BBF7D0"), BrushFromHex("#166534")),
                _           => (BrushFromHex("#F5F3FF"), BrushFromHex("#DDD6FE"), BrushFromHex("#6D28D9")),
            };

    private static bool IsDraftBlocked(DraftQueueItem item)
        => string.Equals(item.State, "queued", StringComparison.OrdinalIgnoreCase)
           && item.NextRetryAt.HasValue
           && item.NextRetryAt.Value > DateTime.Now;

    private Button CreateDraftQueueActionButton(string label, Action onClick, Brush? background = null)
        => CreateQueueFooterButton(label, onClick);
}