using UnityEngine;
using UnityEngine.UI;
using LightGlue.Unity.Game;

namespace LightGlue.Unity.UI
{
    /// <summary>
    /// 光标/跟随平滑设置的场景 UI 控制器。
    /// - 通过 Toggle、Slider 修改 LightGlueCursorSettings 的参数，并自动保存到本地。
    /// - 需在场景中挂到设置面板根节点，并绑定对应的 UI 组件。
    /// </summary>
    public class LightGlueCursorSettingsUI : MonoBehaviour
    {
        [Header("设置数据源")]
        [Tooltip("留空则使用 LightGlueCursorSettings.Instance")]
        public LightGlueCursorSettings cursorSettings;

        [Header("标记器跟随")]
        [Tooltip("标记器平滑开关")]
        public Toggle markerSmoothToggle;

        [Tooltip("标记器跟随速度 Slider（建议 min=1, max=300）")]
        public Slider markerLerpSlider;

        [Tooltip("标记器跟随速度数值显示（可选）")]
        public Text markerLerpValueText;

        [Tooltip("标记器抖动阈值 Slider（建议 min=0, max=50）")]
        public Slider markerJitterSlider;

        [Tooltip("标记器抖动阈值数值显示（可选）")]
        public Text markerJitterValueText;

        [Header("相机朝向跟随")]
        [Tooltip("相机旋转平滑开关")]
        public Toggle cameraSmoothToggle;

        [Tooltip("相机旋转速度 Slider（建议 min=1, max=300）")]
        public Slider cameraLerpSlider;

        [Tooltip("相机旋转速度数值显示（可选）")]
        public Text cameraLerpValueText;

        [Tooltip("相机旋转抖动阈值 Slider（建议 min=0, max=10，单位度）")]
        public Slider cameraJitterSlider;

        [Tooltip("相机旋转抖动阈值数值显示（可选）")]
        public Text cameraJitterValueText;

        [Header("按钮")]
        [Tooltip("恢复默认并保存按钮")]
        public Button resetToDefaultButton;

        [Tooltip("保存到本地按钮（若希望手动保存可绑定；不绑定时各控件修改后会自动保存）")]
        public Button saveButton;

        [Header("Slider 范围（用于恢复默认时设置 Slider 的 value）")]
        [Tooltip("标记器速度 Slider 的 min/max，用于 Refresh 时正确显示")]
        public Vector2 markerLerpRange = new Vector2(1f, 300f);

        public Vector2 markerJitterRange = new Vector2(0f, 50f);
        public Vector2 cameraLerpRange = new Vector2(1f, 300f);
        public Vector2 cameraJitterRange = new Vector2(0f, 10f);

        [Header("本地存储")]
        [Tooltip("滑块/开关修改后，到自动保存到本地之间的时间间隔（秒）")]
        public float autoSaveIntervalSeconds = 0.5f;

        private bool _ignoreChanges;
        private bool _pendingSave;
        private float _lastChangeTime;

        private void Start()
        {
            if (cursorSettings == null)
                cursorSettings = LightGlueCursorSettings.Instance;

            if (cursorSettings == null)
            {
                Debug.LogWarning("[LightGlueCursorSettingsUI] 未找到 LightGlueCursorSettings，请确保场景或预制中存在该组件。");
                return;
            }

            BindListeners();
            RefreshUIFromSettings();
        }

        private void Update()
        {
            if (!_pendingSave || cursorSettings == null)
                return;

            if (Time.unscaledTime - _lastChangeTime >= autoSaveIntervalSeconds)
            {
                cursorSettings.SaveToLocal();
                _pendingSave = false;
            }
        }

        private void BindListeners()
        {
            if (markerSmoothToggle != null)
                markerSmoothToggle.onValueChanged.AddListener(OnMarkerSmoothChanged);
            if (markerLerpSlider != null)
                markerLerpSlider.onValueChanged.AddListener(OnMarkerLerpChanged);
            if (markerJitterSlider != null)
                markerJitterSlider.onValueChanged.AddListener(OnMarkerJitterChanged);
            if (cameraSmoothToggle != null)
                cameraSmoothToggle.onValueChanged.AddListener(OnCameraSmoothChanged);
            if (cameraLerpSlider != null)
                cameraLerpSlider.onValueChanged.AddListener(OnCameraLerpChanged);
            if (cameraJitterSlider != null)
                cameraJitterSlider.onValueChanged.AddListener(OnCameraJitterChanged);
            if (resetToDefaultButton != null)
                resetToDefaultButton.onClick.AddListener(OnResetToDefaultClicked);
            if (saveButton != null)
                saveButton.onClick.AddListener(OnSaveClicked);
        }

        /// <summary>
        /// 根据当前 LightGlueCursorSettings 刷新所有 UI 显示（不触发保存）。
        /// </summary>
        public void RefreshUIFromSettings()
        {
            if (cursorSettings == null) return;

            _ignoreChanges = true;
            try
            {
                if (markerSmoothToggle != null)
                    markerSmoothToggle.isOn = cursorSettings.markerEnableSmoothFollow;
                if (markerLerpSlider != null)
                {
                    markerLerpSlider.minValue = markerLerpRange.x;
                    markerLerpSlider.maxValue = markerLerpRange.y;
                    markerLerpSlider.value = cursorSettings.markerPositionLerpSpeed;
                }
                if (markerJitterSlider != null)
                {
                    markerJitterSlider.minValue = markerJitterRange.x;
                    markerJitterSlider.maxValue = markerJitterRange.y;
                    markerJitterSlider.value = cursorSettings.markerJitterThresholdPixels;
                }
                if (cameraSmoothToggle != null)
                    cameraSmoothToggle.isOn = cursorSettings.cameraAimEnableSmoothRotation;
                if (cameraLerpSlider != null)
                {
                    cameraLerpSlider.minValue = cameraLerpRange.x;
                    cameraLerpSlider.maxValue = cameraLerpRange.y;
                    cameraLerpSlider.value = cursorSettings.cameraAimRotationLerpSpeed;
                }
                if (cameraJitterSlider != null)
                {
                    cameraJitterSlider.minValue = cameraJitterRange.x;
                    cameraJitterSlider.maxValue = cameraJitterRange.y;
                    cameraJitterSlider.value = cursorSettings.cameraAimRotationJitterThresholdDeg;
                }
                UpdateValueLabels();
            }
            finally
            {
                _ignoreChanges = false;
            }
        }

        private void UpdateValueLabels()
        {
            if (markerLerpValueText != null && markerLerpSlider != null)
                markerLerpValueText.text = cursorSettings != null ? cursorSettings.markerPositionLerpSpeed.ToString("F0") : markerLerpSlider.value.ToString("F0");
            if (markerJitterValueText != null && markerJitterSlider != null)
                markerJitterValueText.text = cursorSettings != null ? cursorSettings.markerJitterThresholdPixels.ToString("F1") : markerJitterSlider.value.ToString("F1");
            if (cameraLerpValueText != null && cameraLerpSlider != null)
                cameraLerpValueText.text = cursorSettings != null ? cursorSettings.cameraAimRotationLerpSpeed.ToString("F0") : cameraLerpSlider.value.ToString("F0");
            if (cameraJitterValueText != null && cameraJitterSlider != null)
                cameraJitterValueText.text = cursorSettings != null ? cursorSettings.cameraAimRotationJitterThresholdDeg.ToString("F2") : cameraJitterSlider.value.ToString("F2");
        }

        private void ApplyAndSave()
        {
            if (cursorSettings == null || _ignoreChanges) return;
            _pendingSave = true;
            _lastChangeTime = Time.unscaledTime;
        }

        private void OnMarkerSmoothChanged(bool value)
        {
            if (_ignoreChanges || cursorSettings == null) return;
            cursorSettings.markerEnableSmoothFollow = value;
            ApplyAndSave();
        }

        private void OnMarkerLerpChanged(float value)
        {
            if (_ignoreChanges || cursorSettings == null) return;
            cursorSettings.markerPositionLerpSpeed = value;
            if (markerLerpValueText != null) markerLerpValueText.text = value.ToString("F0");
            ApplyAndSave();
        }

        private void OnMarkerJitterChanged(float value)
        {
            if (_ignoreChanges || cursorSettings == null) return;
            cursorSettings.markerJitterThresholdPixels = value;
            if (markerJitterValueText != null) markerJitterValueText.text = value.ToString("F1");
            ApplyAndSave();
        }

        private void OnCameraSmoothChanged(bool value)
        {
            if (_ignoreChanges || cursorSettings == null) return;
            cursorSettings.cameraAimEnableSmoothRotation = value;
            ApplyAndSave();
        }

        private void OnCameraLerpChanged(float value)
        {
            if (_ignoreChanges || cursorSettings == null) return;
            cursorSettings.cameraAimRotationLerpSpeed = value;
            if (cameraLerpValueText != null) cameraLerpValueText.text = value.ToString("F0");
            ApplyAndSave();
        }

        private void OnCameraJitterChanged(float value)
        {
            if (_ignoreChanges || cursorSettings == null) return;
            cursorSettings.cameraAimRotationJitterThresholdDeg = value;
            if (cameraJitterValueText != null) cameraJitterValueText.text = value.ToString("F2");
            ApplyAndSave();
        }

        private void OnResetToDefaultClicked()
        {
            if (cursorSettings == null) return;
            cursorSettings.ResetToDefaultAndSave();
            RefreshUIFromSettings();
            _pendingSave = false;
        }

        private void OnSaveClicked()
        {
            if (cursorSettings == null) return;
            cursorSettings.SaveToLocal();
            _pendingSave = false;
        }
    }
}