using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace GUI.Dialog.Extender
{
    [ProvideProperty("Hint", typeof(Control))]
    public sealed class HintProvider : Component, IExtenderProvider
    {
        private readonly ToolTip _tip;
        private readonly Dictionary<Control, string> _hints = new Dictionary<Control, string>();
        private readonly Dictionary<Control, EventHandlerGroup> _handlers = new Dictionary<Control, EventHandlerGroup>();

        private readonly Timer _lingerTimer = new Timer() { Interval = 250 }; // 지연 닫기
        private readonly Timer _debounceTimer = new Timer() { Interval = 120 }; // 재표시 디바운스
        private Point _lastPt;
        private string _lastText;
        private Control _lastCtrl;
        private bool _pendingReshow;
        private bool _suspend = true;

        // 기본 동작 설정(원하면 public set 가능)
        [DefaultValue(true)] public bool IsBalloon { get => _tip.IsBalloon; set => _tip.IsBalloon = value; }
        [DefaultValue(true)] public bool ShowAlways { get => _tip.ShowAlways; set => _tip.ShowAlways = value; }
        [DefaultValue(8000)] public int AutoPopDelay { get => _tip.AutoPopDelay; set => _tip.AutoPopDelay = value; }
        [DefaultValue(200)] public int InitialDelay { get => _tip.InitialDelay; set => _tip.InitialDelay = value; }
        [DefaultValue(100)] public int ReshowDelay { get => _tip.ReshowDelay; set => _tip.ReshowDelay = value; }
        [DefaultValue("")] public string Title { get; set; } = "";
        [DefaultValue(ToolTipIcon.None)] public ToolTipIcon Icon { get; set; } = ToolTipIcon.None;
        [DefaultValue(380)] public int MaxWidth { get; set; } = 380;  // 멀티라인 폭 제한

        public HintProvider()
        {
            _tip = new ToolTip { IsBalloon = true, ShowAlways = true, AutoPopDelay = 8000, InitialDelay = 200, ReshowDelay = 100 };
            _tip.Popup += Tip_Popup;

            _lingerTimer.Tick += (s, e) =>
            {
                if (_lastCtrl == null) { _lingerTimer.Stop(); return; }
                // 마우스가 컨트롤 위에 있거나(=재표시 가능성) 캐럿 이동 중이면 유지
                var screen = Cursor.Position;
                var rect = _lastCtrl.RectangleToScreen(_lastCtrl.ClientRectangle);
                if (!rect.Contains(screen)) {
                    _lingerTimer.Stop();
                    _tip.Hide(_lastCtrl);
                }
            };

            _debounceTimer.Tick += (s, e) =>
            {
                _debounceTimer.Stop();
                if (_pendingReshow && _lastCtrl != null) {
                    InternalShow(_lastCtrl, _lastText, _lastPt);
                    _pendingReshow = false;
                }
            };
        }

        public HintProvider(IContainer container) : this()
        {
            container?.Add(this);
        }

        public bool CanExtend(object extendee) => extendee is Control;

        // 확장 속성: Hint
        public string GetHint(Control control)
            => control != null && _hints.TryGetValue(control, out var v) ? v : null;

        public void SetHint(Control control, string value)
        {
            if (control == null) return;

            var had = _hints.ContainsKey(control);
            if (string.IsNullOrWhiteSpace(value)) {
                if (had) {
                    Unhook(control);
                    _hints.Remove(control);
                    _tip.SetToolTip(control, null);
                }
                return;
            }

            _hints[control] = value;
            _tip.SetToolTip(control, value); // 기본값(마우스 hover 시)도 동작하도록 세팅

            if (!had) Hook(control);
        }

        // 팝업 시 크기 조절(멀티라인)
        private void Tip_Popup(object sender, PopupEventArgs e)
        {
            var txt = _tip.GetToolTip(e.AssociatedControl);
            if (string.IsNullOrEmpty(txt)) { e.ToolTipSize = new Size(80, 24); return; }

            var f = new Font("Segoe UI", 9f);
            var sz = TextRenderer.MeasureText(txt, f, new Size(MaxWidth, int.MaxValue), TextFormatFlags.WordBreak);
            var w = Math.Max(80, Math.Min(MaxWidth, sz.Width + 16));
            var h = Math.Max(24, Math.Min(240, sz.Height + 16));
            e.ToolTipSize = new Size(w, h);

            if (!string.IsNullOrEmpty(Title) || Icon != ToolTipIcon.None)
                _tip.ToolTipTitle = Title;
            _tip.ToolTipIcon = Icon;
        }

        private void Hook(Control c)
        {
            var eg = new EventHandlerGroup();

            //eg.Enter = (s, e) => ShowNow(c);
            eg.MouseEnter = (s, e) => ShowNow(c);

            // ❌ 즉시 Hide 금지 —> ⭕ 지연 닫기
            eg.Leave = (s, e) => _lingerTimer.Start();
            eg.MouseLeave = (s, e) => _lingerTimer.Start();

            c.Enter += eg.Enter;
            c.MouseEnter += eg.MouseEnter;
            c.Leave += eg.Leave;
            c.MouseLeave += eg.MouseLeave;

            if (c is TextBoxBase tb) {
        eg.MouseMove   = (s, e) => { if (_tip.Active && IsMouseOver(tb)) ScheduleReshow(tb); };
        eg.TextChanged = (s, e) => { if (_tip.Active && IsMouseOver(tb)) ScheduleReshow(tb); };
        tb.MouseMove   += eg.MouseMove;
        tb.TextChanged += eg.TextChanged;
            }

            _handlers[c] = eg;
        }

        private void ScheduleReshow(TextBoxBase tb)
        {
            if (!_hints.TryGetValue(tb, out var txt) || string.IsNullOrWhiteSpace(txt)) return;
            var pt = GetCaretPointSafe(tb);

            // 위치 변화가 미미하면 무시(진동 방지)
            if (Math.Abs(pt.X - _lastPt.X) + Math.Abs(pt.Y - _lastPt.Y) < 3 && ReferenceEquals(tb, _lastCtrl))
                return;

            _lastCtrl = tb;
            _lastText = txt;
            _lastPt = pt;

            _pendingReshow = true;
            _debounceTimer.Stop();
            _debounceTimer.Start();
        }

        private void ShowNow(Control c)
        {
            if (_suspend) return;            // 폼 뜨기 전에는 아예 표시 금지
            if (!IsMouseOver(c)) return;     // 호버가 아닐 때도 표시 금지

            if (!_hints.TryGetValue(c, out var txt) || string.IsNullOrWhiteSpace(txt)) return;

            _lastCtrl = c;
            _lastText = txt;
            _lastPt = (c is TextBoxBase tb) ? GetCaretPointSafe(tb) : new Point(c.ClientSize.Width / 2, c.ClientSize.Height + 6);
            InternalShow(c, txt, _lastPt);
        }
        public void ActivateOn(Form form)
        {
            if (form == null) return;
            form.Shown += (_, __) => _suspend = false; // 폼 표시 후 활성화
        }
        private static bool IsMouseOver(Control c)
        {
            var screen = Cursor.Position;
            var rect = c.RectangleToScreen(c.ClientRectangle);
            return rect.Contains(screen);
        }
        private void InternalShow(Control c, string text, Point pt)
        {
            // 포인트를 클라이언트 범위로 clamp (음수/과도한 값 방지)
            pt = new Point(
                Math.Max(0, Math.Min(c.ClientSize.Width - 4, pt.X)),
                Math.Max(0, Math.Min(c.ClientSize.Height - 4, pt.Y))
            );

            _lingerTimer.Stop(); // 표시 중에는 닫기 타이머 중단
            _tip.Show(text, c, pt, AutoPopDelay);
        }

        private Point GetCaretPointSafe(TextBoxBase tb)
        {
            var idx = Math.Max(0, Math.Min(tb.TextLength, tb.SelectionStart));
            var pt = tb.GetPositionFromCharIndex(idx);
            // 줄 높이만큼 아래로
            var h = (int)Math.Round(tb.Font.GetHeight(tb.CreateGraphics()));
            pt.Offset(0, h);
            return pt;
        }

        private void Unhook(Control c)
        {
            if (!_handlers.TryGetValue(c, out var eg)) return;

            c.Enter -= eg.Enter;
            c.MouseEnter -= eg.MouseEnter;
            c.Leave -= eg.Leave;
            c.MouseLeave -= eg.MouseLeave;

            if (c is TextBoxBase tb) {
                tb.MouseMove -= eg.MouseMove;
                tb.TextChanged -= eg.TextChanged;
            }

            _handlers.Remove(c);
        }

        private void ShowNearCaret(TextBoxBase tb)
        {
            if (!_hints.TryGetValue(tb, out var txt) || string.IsNullOrWhiteSpace(txt))
                return;

            try {
                var idx = Math.Max(0, tb.SelectionStart);
                var pt = tb.GetPositionFromCharIndex(idx);
                // 줄 높이만큼 아래로
                pt.Offset(0, (int)Math.Round(tb.Font.GetHeight(tb.CreateGraphics())));

                _tip.Show(txt, tb, pt, AutoPopDelay);
            } catch {
                // 폰트/인덱스 이슈 등은 안전하게 무시
                _tip.Show(txt, tb, tb.ClientSize.Width / 2, tb.ClientSize.Height + 6, AutoPopDelay);
            }
        }

        protected override void Dispose(bool disposing)
        {
            if (disposing) {
                foreach (var kv in _handlers.Keys)
                    Unhook(kv);
                _tip?.Dispose();
            }
            base.Dispose(disposing);
        }

        private sealed class EventHandlerGroup
        {
            public EventHandler Enter, Leave, MouseEnter, MouseLeave;
            public MouseEventHandler MouseMove;
            public EventHandler TextChanged;
        }
    }
}