using UnityEngine;
using UnityEngine.UIElements;
using UnityEngine.Audio;
using System.Collections.Generic;
using System.Linq;
using System;
using System.Threading.Tasks;
using OnlyScove.Scripts;
using Hallucinate.Audio;
using PrimeTween;

namespace Hallucinate.UI
{
    public class SettingsController : BaseUIController
    {
        private VisualElement _sidebar;
        private Label _tabTitle;
        private ScrollView _content;
        private Dictionary<string, Button> _tabButtons = new Dictionary<string, Button>();
        private string _activeTab = "GENERAL";

        // Advanced Mouse Metrics
        private Label _mouseMetricsLabel;

        // FPS State
        private bool _fpsVisible;

        // Hover Tracking for Arrow Key Slider Control
        private Slider _hoveredSlider;
        private Action<float> _hoveredOnChanged;
        private float _sliderMin, _sliderMax;

        // Osu-style Volume Overlay
        private VisualElement _volumeOverlay;
        private Label _masterVolLabel;
        private float _masterVol = 80f;

        public override void Initialize(VisualElement uxmlRoot, UIManager manager)
        {
            base.Initialize(uxmlRoot, manager);

            _sidebar = root.Q<VisualElement>("Sidebar");
            _tabTitle = root.Q<Label>("TabTitle");
            _content = root.Q<ScrollView>("SettingsContent");

            // Osu Volume Logic - Registering on Root for Global Wheel Catch
            root.RegisterCallback<WheelEvent>(OnMouseWheel);
            SetupVolumeOverlay();

            root.RegisterCallback<PointerDownEvent>(evt => {
                if (evt.target == root) uiManager.ToggleSettings();
            });

            // Keyboard navigation for sliders
            root.RegisterCallback<KeyDownEvent>(OnKeyDown);

            SetupTab("GeneralTab", "GENERAL");
            SetupTab("VideoTab", "VIDEO");
            SetupTab("SoundTab", "SOUND");
            SetupTab("ControlTab", "CONTROL");

            var closeBtn = root.Q<Button>("CloseSettingsBtn");
            if (closeBtn != null) closeBtn.clicked += () => uiManager.ToggleSettings();

            _masterVol = PlayerPrefs.GetFloat("MasterVolume", 80f);

            SwitchTab("GENERAL");
        }

        private void SetupVolumeOverlay()
        {
            _volumeOverlay = new VisualElement();
            _volumeOverlay.style.position = Position.Absolute;
            _volumeOverlay.style.right = 40;
            _volumeOverlay.style.top = Length.Percent(40);
            _volumeOverlay.style.width = 120;
            _volumeOverlay.style.height = 120;
            _volumeOverlay.style.backgroundColor = new Color(0, 0, 0, 0.8f);
            _volumeOverlay.style.borderTopLeftRadius = 60;
            _volumeOverlay.style.borderTopRightRadius = 60;
            _volumeOverlay.style.borderBottomLeftRadius = 60;
            _volumeOverlay.style.borderBottomRightRadius = 60;
            _volumeOverlay.style.borderTopWidth = 4;
            _volumeOverlay.style.borderBottomWidth = 4;
            _volumeOverlay.style.borderLeftWidth = 4;
            _volumeOverlay.style.borderRightWidth = 4;
            _volumeOverlay.style.borderTopColor = Color.cyan;
            _volumeOverlay.style.borderBottomColor = Color.cyan;
            _volumeOverlay.style.borderLeftColor = Color.cyan;
            _volumeOverlay.style.borderRightColor = Color.cyan;
            _volumeOverlay.style.justifyContent = Justify.Center;
            _volumeOverlay.style.alignItems = Align.Center;
            _volumeOverlay.style.display = DisplayStyle.None;
            _volumeOverlay.pickingMode = PickingMode.Ignore;

            _masterVolLabel = new Label("80%");
            _masterVolLabel.style.color = Color.white;
            _masterVolLabel.style.fontSize = 24;
            _masterVolLabel.style.unityFontStyleAndWeight = FontStyle.Bold;
            _volumeOverlay.Add(_masterVolLabel);

            root.Add(_volumeOverlay);
        }

        private void OnMouseWheel(WheelEvent evt)
        {
            // Osu style: Volume control with scroll wheel
            // Only apply if in the SOUND tab
            if (_activeTab != "SOUND") return;

            if (_hoveredSlider != null)
            {
                // Adjust the hovered slider's value
                float currentVal = _hoveredSlider.value;
                // Determine step size: default to 1% of range, adjusted for 0-100 range.
                float step = (_sliderMax - _sliderMin) / 100f; 
                float newVal = Mathf.Clamp(currentVal - (evt.delta.y * step * 5f), _sliderMin, _sliderMax); // Multiply by a factor to make scroll smoother

                _hoveredSlider.value = newVal;

                // Trigger the associated OnValueChanged callback to save PlayerPrefs etc.
                _hoveredOnChanged?.Invoke(newVal);
                
                evt.StopPropagation(); // Consume the event so it doesn't affect other elements
            }
            else
            {
                // If not hovering a specific slider, control Master Volume
                UpdateMasterVolume(-evt.delta.y * 2f);
                evt.StopPropagation(); // Consume the event
            }
        }

        private void UpdateMasterVolume(float delta)
        {
            _masterVol = Mathf.Clamp(_masterVol + delta, 0f, 100f);
            PlayerPrefs.SetFloat("MasterVolume", _masterVol);
            
            _masterVolLabel.text = $"{Mathf.RoundToInt(_masterVol)}%";
            ShowVolumeOverlay();
        }

        private async void ShowVolumeOverlay()
        {
            _volumeOverlay.style.display = DisplayStyle.Flex;
            _volumeOverlay.style.opacity = 1f;
            await Task.Delay(1500);
            if (_volumeOverlay.style.opacity == 1f)
            {
                Tween.Custom(1f, 0f, duration: 0.5f, onValueChange: val => _volumeOverlay.style.opacity = val)
                    .OnComplete(() => _volumeOverlay.style.display = DisplayStyle.None);
            }
        }

        private void SetupTab(string btnName, string tabId)
        {
            var btn = root.Q<Button>(btnName);
            if (btn != null)
            {
                _tabButtons[tabId] = btn;
                btn.clicked += () => SwitchTab(tabId);
            }
        }

        private void SwitchTab(string tabId)
        {
            _activeTab = tabId;
            _tabTitle.text = tabId;
            
            foreach (var kvp in _tabButtons)
            {
                if (kvp.Key == tabId) kvp.Value.AddToClassList("active-tab");
                else kvp.Value.RemoveFromClassList("active-tab");
            }

            _content.Clear();
            _hoveredSlider = null;

            switch (tabId)
            {
                case "GENERAL": RenderGeneralTab(); break;
                case "VIDEO": RenderVideoTab(); break;
                case "SOUND": RenderSoundTab(); break;
                case "CONTROL": RenderControlTab(); break;
            }
        }

        #region GENERAL TAB
        private void RenderGeneralTab()
        {
            _content.Add(CreateSection("ACCOUNT"));
            string username = PlayerPrefs.GetString("Username", "Guest");
            var userRow = new VisualElement { style = { flexDirection = FlexDirection.Row, alignItems = Align.Center, marginBottom = 10 } };
            var loggedInLabel = new Label("Logged in as: ");
            loggedInLabel.AddToClassList("text-body");
            userRow.Add(loggedInLabel);
            userRow.Add(new Label(username) { style = { color = Color.cyan, marginLeft = 5, unityFontStyleAndWeight = FontStyle.Bold } });
            _content.Add(userRow);

            _content.Add(CreateSection("LANGUAGE"));
            var langDropdown = new DropdownField(new List<string> { "English", "Tiếng Việt" }, 
                LocalizationManager.Instance?.CurrentLanguage == "vi" ? 1 : 0);
            langDropdown.AddToClassList("custom-dropdown");
            langDropdown.RegisterValueChangedCallback(evt => {
                LocalizationManager.Instance?.LoadLanguage(evt.newValue == "Tiếng Việt" ? "vi" : "en");
                SwitchTab("GENERAL");
            });
            _content.Add(langDropdown);

            _content.Add(CreateSection("UPDATES"));
            var versionBox = new VisualElement { style = { flexDirection = FlexDirection.Row, alignItems = Align.Center } };
            var versionLabel = new Label($"Version: {Application.version}");
            versionLabel.AddToClassList("text-body");
            versionBox.Add(versionLabel);
            var checkBtn = new Button { text = "CHECK FOR UPDATES" };
            checkBtn.AddToClassList("button-spring");
            checkBtn.clicked += () => checkBtn.text = "UP TO DATE";
            versionBox.Add(checkBtn);
            _content.Add(versionBox);

            _content.Add(CreateSection("CURSOR & MOUSE"));
            _content.Add(CreateSliderWithInput("Cursor Size", 10, 150, PlayerPrefs.GetFloat("CursorSize", 40), val => PlayerPrefs.SetFloat("CursorSize", val)));
            
            var trailToggle = new Toggle("Enable Cursor Trail") { value = PlayerPrefs.GetInt("CursorTrail", 1) == 1 };
            trailToggle.RegisterValueChangedCallback(evt => PlayerPrefs.SetInt("CursorTrail", evt.newValue ? 1 : 0));
            _content.Add(trailToggle);

            var rippleToggle = new Toggle("Enable Ripple Effects") { value = PlayerPrefs.GetInt("CursorRipples", 1) == 1 };
            rippleToggle.RegisterValueChangedCallback(evt => PlayerPrefs.SetInt("CursorRipples", evt.newValue ? 1 : 0));
            _content.Add(rippleToggle);

            _content.Add(CreateSliderWithInput("Sensitivity", 0.1f, 5.0f, PlayerPrefs.GetFloat("MouseSensitivity", 1.0f), val => PlayerPrefs.SetFloat("MouseSensitivity", val)));

            var rawInputToggle = new Toggle("Raw Input (Bypass Acceleration)") { value = true };
            _content.Add(rawInputToggle);

            _mouseMetricsLabel = new Label("[(report: 0/sec latency: 0ms)]") { style = { fontSize = 11, color = Color.gray, marginTop = 5 } };
            _content.Add(_mouseMetricsLabel);
        }
        #endregion

        #region VIDEO TAB
        private void RenderVideoTab()
        {
            _content.Add(CreateSection("RENDERER"));
            var frameLimit = new DropdownField("Frame Limiter", new List<string> { "VSync", "Power Saving", "Optimal", "Unlimited" }, 2);
            frameLimit.RegisterValueChangedCallback(evt => {
                switch (evt.newValue) {
                    case "VSync": QualitySettings.vSyncCount = 1; Application.targetFrameRate = -1; break;
                    case "Power Saving": QualitySettings.vSyncCount = 0; Application.targetFrameRate = 60; break;
                    case "Optimal": QualitySettings.vSyncCount = 0; Application.targetFrameRate = 144; break;
                    case "Unlimited": QualitySettings.vSyncCount = 0; Application.targetFrameRate = 999; break;
                }
            });
            _content.Add(frameLimit);

            var fpsToggle = new Toggle("Show FPS Counter") { value = _fpsVisible };
            fpsToggle.RegisterValueChangedCallback(evt => { _fpsVisible = evt.newValue; PerformanceOverlay.SetVisible(_fpsVisible); });
            _content.Add(fpsToggle);

            _content.Add(CreateSection("LAYOUT"));
            Resolution native = Screen.currentResolution;
            var resList = Screen.resolutions.Select(r => $"{r.width}x{r.height}").Distinct().Select(s => s == $"{native.width}x{native.height}" ? s + " (native)" : s).ToList();
            var resDropdown = new DropdownField("Resolution", resList, resList.FindIndex(s => s.Contains("native")));
            resDropdown.RegisterValueChangedCallback(evt => {
                string[] parts = evt.newValue.Split(' ')[0].Split('x');
                Screen.SetResolution(int.Parse(parts[0]), int.Parse(parts[1]), Screen.fullScreen);
            });
            _content.Add(resDropdown);

            var fullToggle = new Toggle("Fullscreen Mode") { value = Screen.fullScreen };
            fullToggle.RegisterValueChangedCallback(evt => Screen.fullScreen = evt.newValue);
            _content.Add(fullToggle);

            _content.Add(CreateSliderWithInput("Background Dim", 0, 100, PlayerPrefs.GetFloat("BackgroundDim", 50), val => PlayerPrefs.SetFloat("BackgroundDim", val)));
            _content.Add(CreateSliderWithInput("UI Scale", 0.5f, 2.0f, PlayerPrefs.GetFloat("UIScale", 1.0f), val => uiManager.SetUIScale(val)));
        }
        #endregion

        #region SOUND TAB
        private void RenderSoundTab()
        {
            _content.Add(CreateSection("AUDIO VOLUMES"));
            _content.Add(CreateAudioSlider("Master", "MasterVolume"));
            _content.Add(CreateAudioSlider("Music", "MusicVolume"));
            _content.Add(CreateAudioSlider("VFX", "VFXVolume"));
            _content.Add(CreateAudioSlider("Player", "PlayerVolume"));
            _content.Add(CreateAudioSlider("UI", "UIVolume"));

            _content.Add(new Label("Use Scroll Wheel to control volume.") { style = { marginTop = 20, color = Color.gray, fontSize = 12 } });
        }

        private VisualElement CreateAudioSlider(string label, string prefKey)
        {
            var sliderRow = CreateSliderWithInput(label, 0, 100, PlayerPrefs.GetFloat(prefKey, 80), val => PlayerPrefs.SetFloat(prefKey, val));
            
            // Register wheel specifically on this row
            sliderRow.RegisterCallback<WheelEvent>(evt => {
                float current = PlayerPrefs.GetFloat(prefKey, 80f);
                float newVal = Mathf.Clamp(current - (evt.delta.y * 2f), 0f, 100f);
                PlayerPrefs.SetFloat(prefKey, newVal);
                
                // Visual update only (to avoid heavy re-render of whole list)
                var slider = sliderRow.Q<Slider>();
                if (slider != null) slider.value = newVal;
            });

            return sliderRow;
        }
        #endregion

        #region CONTROL TAB
        private void RenderControlTab()
        {
            _content.Add(CreateSection("KEY BINDINGS"));
            var pendingLabel = new Label("Controls Implementation Pending context.");
            pendingLabel.AddToClassList("text-body");
            _content.Add(pendingLabel);
        }
        #endregion

        private VisualElement CreateSection(string title)
        {
            var label = new Label(title);
            label.AddToClassList("setting-section-header");
            label.style.marginTop = 20;
            return label;
        }

        private VisualElement CreateSliderWithInput(string labelText, float min, float max, float startVal, Action<float> OnValueChanged)
        {
            var row = new VisualElement { style = { flexDirection = FlexDirection.Row, alignItems = Align.Center, marginTop = 5, marginBottom = 5 } };
            var label = new Label(labelText) { style = { width = Length.Percent(35) } };
            label.AddToClassList("text-body");

            var slider = new Slider(min, max) { value = startVal, style = { flexGrow = 1 } };
            var input = new TextField { value = startVal.ToString("F1"), style = { width = 50, marginLeft = 10 } };
            input.AddToClassList("input-field");

            slider.RegisterCallback<PointerEnterEvent>(evt => { 
                _hoveredSlider = slider; 
                _hoveredOnChanged = OnValueChanged; 
                _sliderMin = min; 
                _sliderMax = max; 
            });
            slider.RegisterCallback<PointerLeaveEvent>(evt => { 
                if (_hoveredSlider == slider) {
                    _hoveredSlider = null; 
                    _hoveredOnChanged = null;
                }
            });

            slider.RegisterValueChangedCallback(evt => {
                float val = Mathf.Round(evt.newValue * 10f) / 10f;
                if (input.panel?.focusController?.focusedElement != input.ElementAt(0)) input.value = val.ToString("F1");
                OnValueChanged?.Invoke(val);
            });

            input.RegisterValueChangedCallback(evt => {
                if (float.TryParse(evt.newValue, out float val)) {
                    slider.value = Mathf.Clamp(val, min, max);
                    OnValueChanged?.Invoke(slider.value);
                }
            });

            row.Add(label);
            row.Add(slider);
            row.Add(input);
            return row;
        }

        private void OnKeyDown(KeyDownEvent evt)
        {
            if (_hoveredSlider == null) return;
            float step = (_sliderMax - _sliderMin) / 100f; 
            if (evt.keyCode == KeyCode.LeftArrow) _hoveredSlider.value -= step;
            if (evt.keyCode == KeyCode.RightArrow) _hoveredSlider.value += step;
        }

        public override void Update()
        {
            if (_activeTab == "GENERAL" && _mouseMetricsLabel != null)
            {
                var (polling, latency) = MouseMetricsHelper.GetMetrics();
                _mouseMetricsLabel.text = $"[(report: {polling}/sec latency: {latency:F0}ms)]";
            }
        }

        public override async Task PlayTransitionIn()
        {
            root.style.display = DisplayStyle.Flex;
            _sidebar.style.translate = new StyleTranslate(new Translate(Length.Percent(-100), 0));
            await Tween.Custom(-100f, 0f, duration: 0.4f, ease: Ease.OutQuad, onValueChange: val => _sidebar.style.translate = new StyleTranslate(new Translate(Length.Percent(val), 0)));
        }

        public override async Task PlayTransitionOut()
        {
            await Tween.Custom(0f, -100f, duration: 0.3f, ease: Ease.InQuad, onValueChange: val => _sidebar.style.translate = new StyleTranslate(new Translate(Length.Percent(val), 0)));
            Hide();
        }
    }
}