// Copyright (c) Microsoft Corporation. All rights reserved.
// Licensed under the MIT License. See LICENSE in the project root for license information.

using UnityEngine;
using UnityEngine.UI;

namespace HoloToolkit.UI.Keyboard
{
    public class SymbolDisableHighlight : MonoBehaviour
    {
        /// <summary>
        /// The text field to update.
        /// </summary>
        [SerializeField]
        private Text m_TextField;

        /// <summary>
        /// The text field to update.
        /// </summary>
        [SerializeField]
        private Image m_ImageField;

        /// <summary>
        /// The color to switch to when the button is disabled.
        /// </summary>
        [SerializeField]
        private Color m_DisabledColor = Color.grey;

        /// <summary>
        /// The color the text field starts as.
        /// </summary>
        private Color m_StartingColor;

        /// <summary>
        /// The button to check for disabled/enabled.
        /// </summary>
        private Button m_Button;

        /// <summary>
        /// Standard Unity start.
        /// </summary>
        private void Start()
        {
            if (m_TextField != null)
            {
	            m_StartingColor = m_TextField.color;
            }

            if (m_ImageField != null)
            {
                m_StartingColor = m_ImageField.color;
            }

            m_Button = GetComponentInParent<Button>();

            UpdateState();
        }

        /// <summary>
        /// Standard Unity update.
        /// </summary>
        private void Update()
        {
            UpdateState();
        }

        /// <summary>
        /// Updates the visual state of the text based on the buttons state.
        /// </summary>
        private void UpdateState()
        {
            if (m_TextField != null && m_Button != null)
            {
	            m_TextField.color = m_Button.interactable ? m_StartingColor : m_DisabledColor;
            }

            if (m_ImageField != null && m_Button != null)
            {
                m_ImageField.color = m_Button.interactable ? m_StartingColor : m_DisabledColor;
            }
        }
	}
}
