using System;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Controls.Primitives;
using System.Windows.Media;

namespace ivf_tl_Operate.CustomUserControls
{
    /// <summary>
    /// 软键盘模式。
    /// </summary>
    public enum SoftKeyboardMode
    {
        /// <summary>数字键盘（0-9 / 退格 / 清除 / 确定）—— 数字/参数输入。</summary>
        Number,
        /// <summary>密码/全键盘（字母+数字+常用符号）—— 登录/调试密码。</summary>
        Password
    }

    /// <summary>
    /// M4-04-1 · 自绘内置软键盘控件（数字键盘 + 密码/全键盘）。
    /// <para>
    /// 取代 osk.exe（需求 11）。键盘维护一份内部输入缓冲，所有按键只在缓冲上增删，
    /// 每次变化通过 <see cref="KeyInput"/> 把「当前完整文本」抛给宿主（SoftKeyboardHost），
    /// 由宿主写回目标 TextBox/PasswordBox。点 确定/× 触发 <see cref="RequestClose"/>，
    /// 由宿主收起键盘。键盘不直接引用任何页面或具体输入框，做到代码隔离、可复用。
    /// </para>
    /// <para>不涉及任何业务/密码校验逻辑：tl13579 比对、参数阈值校验仍在原页面，键盘只负责录入。</para>
    /// </summary>
    public partial class SoftKeyboard : UserControl
    {
        private readonly StringBuilder _buffer = new StringBuilder();
        private bool _shift; // 全键盘大小写
        private bool _fullPadBuilt;

        /// <summary>当前缓冲文本变化（参数为当前完整文本）。宿主据此写回目标输入框。</summary>
        public event Action<string> KeyInput;

        /// <summary>用户点「确定」或「×」请求收起键盘（参数：true=确定提交，false=取消/关闭）。</summary>
        public event Action<bool> RequestClose;

        public SoftKeyboard()
        {
            InitializeComponent();
        }

        #region 依赖属性

        /// <summary>键盘模式（数字 / 密码全键盘）。</summary>
        public SoftKeyboardMode KeyboardMode
        {
            get => (SoftKeyboardMode)GetValue(KeyboardModeProperty);
            set => SetValue(KeyboardModeProperty, value);
        }

        public static readonly DependencyProperty KeyboardModeProperty =
            DependencyProperty.Register(nameof(KeyboardMode), typeof(SoftKeyboardMode), typeof(SoftKeyboard),
                new PropertyMetadata(SoftKeyboardMode.Number, OnKeyboardModeChanged));

        private static void OnKeyboardModeChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            if (d is SoftKeyboard kb) kb.ApplyMode();
        }

        /// <summary>预览/回显时是否按密码掩码（●）显示。默认随模式：Password=掩码。可被宿主覆盖。</summary>
        public bool MaskPreview
        {
            get => (bool)GetValue(MaskPreviewProperty);
            set => SetValue(MaskPreviewProperty, value);
        }

        public static readonly DependencyProperty MaskPreviewProperty =
            DependencyProperty.Register(nameof(MaskPreview), typeof(bool), typeof(SoftKeyboard),
                new PropertyMetadata(false));

        #endregion

        /// <summary>当前键盘缓冲内容。</summary>
        public string Text => _buffer.ToString();

        /// <summary>
        /// 重置键盘：设定模式 + 初始文本（用于绑定输入框时把已有值带入）。宿主弹出前调用。
        /// </summary>
        public void Reset(SoftKeyboardMode mode, string initialText, bool mask)
        {
            _buffer.Clear();
            if (!string.IsNullOrEmpty(initialText)) _buffer.Append(initialText);
            _shift = false;
            MaskPreview = mask;
            KeyboardMode = mode; // 触发 ApplyMode
            ApplyMode();
            UpdatePreview();
        }

        private void ApplyMode()
        {
            if (_numberPad == null) return; // 未加载
            if (KeyboardMode == SoftKeyboardMode.Password)
            {
                BuildFullPadOnce();
                _numberPad.Visibility = Visibility.Collapsed;
                _fullPad.Visibility = Visibility.Visible;
            }
            else
            {
                _numberPad.Visibility = Visibility.Visible;
                _fullPad.Visibility = Visibility.Collapsed;
            }
        }

        #region 全键盘按键动态构建（触控基准统一应用）

        private void BuildFullPadOnce()
        {
            if (_fullPadBuilt) return;
            FillRow(_rowDigits, "1234567890");
            FillRow(_rowQ, "qwertyuiop");
            FillRow(_rowA, "asdfghjkl");
            FillRow(_rowZ, "zxcvbnm");
            _fullPadBuilt = true;
        }

        private void FillRow(System.Windows.Controls.Primitives.UniformGrid host, string chars)
        {
            foreach (char c in chars)
            {
                var b = new Button
                {
                    Content = c.ToString(),
                    Tag = c.ToString(),
                    Margin = new Thickness(2)
                };
                b.Click += Key_Click;
                host.Children.Add(b);
            }
        }

        #endregion

        #region 按键事件

        private void Key_Click(object sender, RoutedEventArgs e)
        {
            if (!(sender is Button b) || b.Tag == null) return;
            string ch = b.Tag.ToString();
            // 全键盘 Shift：字母大写
            if (KeyboardMode == SoftKeyboardMode.Password && _shift && ch.Length == 1 && char.IsLetter(ch[0]))
                ch = ch.ToUpperInvariant();
            _buffer.Append(ch);
            EmitChanged();
        }

        private void Back_Click(object sender, RoutedEventArgs e)
        {
            if (_buffer.Length > 0) _buffer.Remove(_buffer.Length - 1, 1);
            EmitChanged();
        }

        private void Clear_Click(object sender, RoutedEventArgs e)
        {
            _buffer.Clear();
            EmitChanged();
        }

        private void Shift_Click(object sender, RoutedEventArgs e)
        {
            _shift = !_shift;
            if (_shiftBtn != null)
                _shiftBtn.Background = _shift
                    ? new SolidColorBrush(Color.FromRgb(0x4D, 0x75, 0xAC))
                    : new SolidColorBrush(Color.FromRgb(0xB0, 0xB4, 0xB9));
        }

        private void Enter_Click(object sender, RoutedEventArgs e)
        {
            RequestClose?.Invoke(true);
        }

        private void Close_Click(object sender, RoutedEventArgs e)
        {
            RequestClose?.Invoke(false);
        }

        #endregion

        private void EmitChanged()
        {
            UpdatePreview();
            KeyInput?.Invoke(_buffer.ToString());
        }

        private void UpdatePreview()
        {
            if (_preview == null) return;
            if (MaskPreview)
                _preview.Text = new string('●', _buffer.Length);
            else
                _preview.Text = _buffer.ToString();
        }
    }
}