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

namespace SimpleApp
{
    public class AlertBox
    {
        private Activity Activity { get; set; }
        private bool Cancelable { get; set; }
        private int Theme { get; set; }

        private AlertDialog dialog { get; set; }

        public AlertBox(Activity activity, bool cancelable, int theme)
        {
            Activity = activity;
            Cancelable = cancelable;
            Theme = theme;
        }

        public AlertBox(Activity activity, bool cancelable)
            : this(activity, cancelable, -1)
        {
            Activity = activity;
            Cancelable = cancelable;
        }

        public AlertBox(Activity activity)
            : this(activity, true, -1)
        { }

        private AlertDialog.Builder CreateBuilder()
        {
            return (Theme != -1) ? new AlertDialog.Builder(Activity, Theme) : new AlertDialog.Builder(Activity);
        }

        public void ShowMessage(string title, string message,
            string positiveButton, Action onPositiveClick,
            string negativeButton, Action onNegativeClick)
        {
            using (AlertDialog.Builder builder = CreateBuilder())
            {
                builder.SetCancelable(Cancelable);
                if (!string.IsNullOrEmpty(positiveButton)) builder.SetPositiveButton(positiveButton, (s, e) => { if (onPositiveClick != null) onPositiveClick(); });
                if (!string.IsNullOrEmpty(negativeButton)) builder.SetNegativeButton(negativeButton, (s, e) => { if (onNegativeClick != null) onNegativeClick(); });
                builder.SetMessage(message);
                builder.SetTitle(title);
                builder.Create();
                dialog = builder.Show();
            }
        }

        public void ShowMessageOkCancel(string title, string message, Action onPositiveClick = null, Action onNegativeClick = null)
        {
            ShowMessage(title, message, Activity.GetString(Android.Resource.String.Ok), onPositiveClick, Activity.GetString(Android.Resource.String.Cancel), onNegativeClick);
        }

        private void ShowSingleChoice(string title, string[] choiceItems, int checkedItem,
            EventHandler<DialogClickEventArgs> onChoiceClick,
            string positiveButton, EventHandler<DialogClickEventArgs> onPositiveClick,
            string negativeButton, EventHandler<DialogClickEventArgs> onNegativeClick)
        {
            using (AlertDialog.Builder builder = CreateBuilder())
            {
                builder.SetCancelable(Cancelable);
                if (!string.IsNullOrEmpty(positiveButton)) builder.SetPositiveButton(positiveButton, (s, e) => { if (onPositiveClick != null) onPositiveClick(s, e); });
                if (!string.IsNullOrEmpty(negativeButton)) builder.SetNegativeButton(negativeButton, (s, e) => { if (onNegativeClick != null) onNegativeClick(s, e); });
                builder.SetSingleChoiceItems(choiceItems, checkedItem, (s, e) => { if (onChoiceClick != null) onChoiceClick(s, e); });
                builder.SetTitle(title);
                builder.Create();
                dialog = builder.Show();
            }
        }

        public void ShowSingleChoice(string title, string[] choiceItems, int checkedItem, string positiveButton = null, Action<int> onPositiveClick = null, string negativeButton = null, Action onNegativeClick = null)
        {
            if (!string.IsNullOrEmpty(positiveButton))
            {
                ShowSingleChoice(
                    title, choiceItems, checkedItem,
                    (s, e) => { checkedItem = e.Which; },
                    positiveButton, (s, e) => { if (onPositiveClick != null) onPositiveClick(checkedItem); },
                    negativeButton, (s, e) => { if (onNegativeClick != null) onNegativeClick(); });
            }
            else
            {
                ShowSingleChoice(
                    title, choiceItems, checkedItem,
                    (s, e) => { if (onPositiveClick != null) onPositiveClick(e.Which); if (dialog != null) dialog.Dismiss(); },
                    null, null,
                    negativeButton, (s, e) => { if (onNegativeClick != null) onNegativeClick(); });
            }
        }

        public void ShowSingleChoiceOkCancel(string title, string[] choiceItems, int checkedItem, Action<int> onPositiveClick = null, Action onNegativeClick = null)
        {
            ShowSingleChoice(title, choiceItems, checkedItem, Activity.GetString(Android.Resource.String.Ok), onPositiveClick, Activity.GetString(Android.Resource.String.Cancel), onNegativeClick);
        }

        public void ShowSingleChoiceCancel(string title, string[] choiceItems, int checkedItem, Action<int> onPositiveClick = null, Action onNegativeClick = null)
        {
            ShowSingleChoice(title, choiceItems, checkedItem, null, onPositiveClick, Activity.GetString(Android.Resource.String.Cancel), onNegativeClick);
        }

        private void ShowMultiChoice(string title, string[] choiceItems, bool[] checkedItems,
            EventHandler<DialogMultiChoiceClickEventArgs> onChoiceClick,
            string positiveButton, EventHandler<DialogClickEventArgs> onPositiveClick,
            string negativeButton, EventHandler<DialogClickEventArgs> onNegativeClick)
        {
            using (AlertDialog.Builder builder = CreateBuilder())
            {
                builder.SetCancelable(Cancelable);
                if (!string.IsNullOrEmpty(positiveButton)) builder.SetPositiveButton(positiveButton, (s, e) => { if (onPositiveClick != null) onPositiveClick(s, e); });
                if (!string.IsNullOrEmpty(negativeButton)) builder.SetNegativeButton(negativeButton, (s, e) => { if (onNegativeClick != null) onNegativeClick(s, e); });

                bool[] checkedItems2 = new bool[choiceItems.Length];
                if (checkedItems != null)
                    for (int i = 0; i < Math.Min(checkedItems.Length, checkedItems2.Length); i++)
                        checkedItems2[i] = checkedItems[i];

                builder.SetMultiChoiceItems(choiceItems, checkedItems2, (s, e) => { if (onChoiceClick != null) onChoiceClick(s, e); });
                builder.SetTitle(title);
                builder.Create();
                dialog = builder.Show();
            }
        }

        public void ShowMultiChoice(string title, string[] choiceItems, bool[] checkedItems, string positiveButton = null, Action<bool[]> onPositiveClick = null, string negativeButton = null, Action onNegativeClick = null)
        {
            ShowMultiChoice(
                title, choiceItems, checkedItems,
                (s, e) => { checkedItems[e.Which] = e.IsChecked; },
                positiveButton, (s, e) => { if (onPositiveClick != null) onPositiveClick(checkedItems); },
                negativeButton, (s, e) => { if (onNegativeClick != null) onNegativeClick(); });
        }

        public void ShowMultiChoiceOkCancel(string title, string[] choiceItems, bool[] checkedItems, Action<bool[]> onPositiveClick = null, Action onNegativeClick = null)
        {
            ShowMultiChoice(title, choiceItems, checkedItems, Activity.GetString(Android.Resource.String.Ok), onPositiveClick, Activity.GetString(Android.Resource.String.Cancel), onNegativeClick);
        }
    }
}