using System;
using Android.App;
using Android.Content;


namespace Shared
{
    /// <summary>
    /// 对话框
    /// </summary>
    public class Alert
    {
        /// <summary>
        /// 当前信息框对象
        /// </summary>
        AlertDialog.Builder builder;

        /// <summary>
        /// 对话窗
        /// </summary>
        /// <param name="title">标题</param>
        /// <param name="message">信息</param>
        /// <param name="cancelButtonText">取消按键备注，值null表示不显示取消按键</param>
        /// <param name="okButtonText">确认按键备注</param>
        public Alert (string title, string message, string cancelButtonText, string okButtonText)
        {
            builder = new AlertDialog.Builder (Application.Activity);
            builder.SetMessage (message);
            builder.SetTitle (title);
            builder.SetCancelable (false);
            builder.SetPositiveButton (okButtonText, new EventHandler<DialogClickEventArgs> ((sender, e) => {
                ResultEventHandler?.Invoke(this, true);
            }));

            if (cancelButtonText != null) {
                builder.SetNegativeButton (cancelButtonText, new EventHandler<DialogClickEventArgs> ((sender, e) => {
                    ResultEventHandler?.Invoke(this, false);
                }));
            }
        }

        /// <summary>
        /// 对话窗
        /// </summary>
        /// <param name="title">标题</param>
        /// <param name="message">信息</param>
        /// <param name="okButtonText">确认按键备注</param>
        public Alert (string title, string message, string okButtonText) : this (title, message, null, okButtonText) { }

        /// <summary>
        /// 结果通知事件，true表示选中按键，false表示取消事件
        /// </summary>
        public Action<Alert, bool> ResultEventHandler;
		
        /// <summary>
		/// 显示当前的界面
		/// </summary>
		public void Show()
		{
			builder.Show();
		}
	}
}