using Unity.XR.CoreUtils;
using UnityEngine.XR.Interaction.Toolkit.Interactables;

namespace UnityEngine.XR.Interaction.Toolkit.Samples.VisionOS
{
    /// <summary>
    /// Toggle component that can be poked or indirectly interacted with to toggle its state.
    /// </summary>
    public class ToggleComponent : XRBaseInteractable
    {
        [Header("Toggle References")]
        [SerializeField]
        Transform m_ToggleBubble;

        [SerializeField]
        MeshRenderer m_ToggleBackground;

        [Header("Toggle Colors")]
        [SerializeField]
        Color m_SelectedColor = new Color(.1254f, .5882f, .9529f);

        [SerializeField]
        Color m_UnselectedColor = new Color(.1764f, .1764f, .1764f);

        [Header("Toggle Animation")]
        [SerializeField]
        float m_TransitionDuration = 0.15f;

        [Header("Toggle Events")]
        [SerializeField]
        BoolUnityEvent m_OnToggleChanged;

        bool m_IsOn = true;
        bool m_IsAnimating;
        Vector3 m_BubbleOnTargetPosition;
        Vector3 m_BubbleOffTargetPosition;

        float m_StartLerpTime;

        const float k_BubbleOnPosition = -0.17f;
        const float k_BubbleOffPosition = 0.17f;

        Material m_MaterialInstance;

        void Start()
        {
            var bubblePosition = m_ToggleBubble.localPosition;
            m_BubbleOnTargetPosition = new Vector3(k_BubbleOnPosition, bubblePosition.y, bubblePosition.z);
            m_BubbleOffTargetPosition = new Vector3(k_BubbleOffPosition, bubblePosition.y, bubblePosition.z);

            m_MaterialInstance = m_ToggleBackground.material;
            SetBubbleColor(m_IsOn ? m_SelectedColor : m_UnselectedColor);
        }

        /// <inheritdoc />
        protected override void OnSelectEntered(SelectEnterEventArgs args)
        {
            base.OnSelectEntered(args);

            m_IsOn = !m_IsOn;
            m_StartLerpTime = Time.time;
            m_IsAnimating = true;
            m_OnToggleChanged?.Invoke(m_IsOn);
        }

        void Update()
        {
            if (!m_IsAnimating)
                return;

            var lerpPercentage = Mathf.Clamp01(Time.time - m_StartLerpTime) / m_TransitionDuration;

            m_ToggleBubble.localPosition = Vector3.Lerp(
                m_IsOn ? m_BubbleOffTargetPosition : m_BubbleOnTargetPosition,
                m_IsOn ? m_BubbleOnTargetPosition : m_BubbleOffTargetPosition,
                lerpPercentage);

            SetBubbleColor(Color.Lerp(m_IsOn ? m_UnselectedColor : m_SelectedColor,
                m_IsOn ? m_SelectedColor : m_UnselectedColor,
                lerpPercentage));

            if (lerpPercentage >= 1f)
                m_IsAnimating = false;
        }

        void SetBubbleColor(Color color)
        {
            m_MaterialInstance.color = color;
        }
    }
}