using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using UnityEngine.SceneManagement;
using UnityEngine.InputSystem;

public class PauseMenu : MonoBehaviour
{
    [Header("Панели")]
    public GameObject pauseMenuPanel;
    public GameObject settingsPanel;

    [Header("Кнопки панели действий")]
    public Button resumeButton;
    public Button restartButton;
    public Button mainMenuButton;
    public Button quitButton;

    [Header("Вкладки")]
    public Button[] tabButtons;
    public GameObject[] tabPanels;

    [Header("Настройки: Звук")]
    public Slider volumeSlider;
    public Text volumeValueText;
    public Toggle muteToggle;

    [Header("Настройки: Графика")]
    public Dropdown qualityDropdown;
    public Toggle fullscreenToggle;
    public Dropdown resolutionDropdown;
    public Toggle vsyncToggle;

    [Header("Настройки: Управление")]
    public Slider sensitivitySlider;
    public Text sensitivityValueText;
    public Toggle invertYToggle;

    private bool isPaused = false;
    private bool isInitializing = false;
    private bool wasCursorLocked = false;
    private List<Resolution> filteredResolutions = new List<Resolution>();

    public bool IsPaused => isPaused;

    private void Awake()
    {
        AutoWireUI();
    }

    private void Start()
    {
        AutoWireUI();

        if (pauseMenuPanel != null) pauseMenuPanel.SetActive(false);
        if (settingsPanel != null && settingsPanel != pauseMenuPanel) settingsPanel.SetActive(false);

        SetupActionButtons();
        SetupTabs();
        InitializeSettingsUI();

        wasCursorLocked = (Cursor.lockState == CursorLockMode.Locked);
    }

    private void Update()
    {
        // Не открываем меню паузы, если активен экран смерти
        if (DeathScreenUI.Instance != null && DeathScreenUI.Instance.IsShown) return;

        bool togglePause = false;
        var keyboard = Keyboard.current;
        if (keyboard != null)
        {
            if (keyboard.escapeKey.wasPressedThisFrame ||
                keyboard.pKey.wasPressedThisFrame ||
                keyboard.tabKey.wasPressedThisFrame ||
                keyboard.pauseKey.wasPressedThisFrame)
            {
                togglePause = true;
            }
        }

        var gamepad = Gamepad.current;
        if (gamepad != null && gamepad.startButton.wasPressedThisFrame)
        {
            togglePause = true;
        }

#if UNITY_EDITOR
        // В Unity Editor при заблокированном курсоре нажатие Escape перехватывается редактором
        // для снятия блокировки курсора (Cursor.lockState переключается в None) и не передается в Update().
        // Поэтому в редакторе переключение lockState из Locked в None трактуется как нажатие Escape!
        if (!isPaused && wasCursorLocked && Cursor.lockState != CursorLockMode.Locked)
        {
            togglePause = true;
        }
        wasCursorLocked = (Cursor.lockState == CursorLockMode.Locked);
#endif

        if (togglePause)
        {
            if (isPaused)
            {
                if (settingsPanel != null && settingsPanel.activeSelf && settingsPanel != pauseMenuPanel)
                {
                    CloseSettings();
                }
                else
                {
                    ResumeGame();
                }
            }
            else
            {
                PauseGame();
            }
        }
    }

    public void PauseGame()
    {
        isPaused = true;
        Time.timeScale = 0f;
        Cursor.lockState = CursorLockMode.None;
        Cursor.visible = true;
        wasCursorLocked = false;

        if (pauseMenuPanel != null)
        {
            pauseMenuPanel.SetActive(true);
            SwitchTab(0);
        }

        if (settingsPanel != null && settingsPanel != pauseMenuPanel)
        {
            settingsPanel.SetActive(false);
        }

        Debug.Log("[PauseMenu] Game PAUSED (Esc/P/Tab pressed). Time.timeScale=0.");
    }

    public void ResumeGame()
    {
        isPaused = false;
        Time.timeScale = 1f;
        Cursor.lockState = CursorLockMode.Locked;
        Cursor.visible = false;
        wasCursorLocked = true;

        if (pauseMenuPanel != null) pauseMenuPanel.SetActive(false);
        if (settingsPanel != null) settingsPanel.SetActive(false);
        Debug.Log("[PauseMenu] Game RESUMED. Time.timeScale=1.");
    }

    public void RestartGame()
    {
        Time.timeScale = 1f;
        Cursor.lockState = CursorLockMode.Locked;
        Cursor.visible = false;
        SceneManager.LoadScene(SceneManager.GetActiveScene().name);
    }

    public void OpenSettings()
    {
        if (pauseMenuPanel != null) pauseMenuPanel.SetActive(false);
        if (settingsPanel != null) settingsPanel.SetActive(true);
    }

    public void CloseSettings()
    {
        PlayerPrefs.Save();
        if (settingsPanel != null) settingsPanel.SetActive(false);
        if (pauseMenuPanel != null) pauseMenuPanel.SetActive(true);
    }

    public void ReturnToMainMenu()
    {
        Time.timeScale = 1f;
        Cursor.lockState = CursorLockMode.None;
        Cursor.visible = true;
        SceneManager.LoadScene("MainMenu");
    }

    public void QuitGame()
    {
        PlayerPrefs.Save();
        Application.Quit();
#if UNITY_EDITOR
        UnityEditor.EditorApplication.isPlaying = false;
#endif
    }

    public void SwitchTab(int tabIndex)
    {
        if (tabPanels != null)
        {
            for (int i = 0; i < tabPanels.Length; i++)
            {
                if (tabPanels[i] != null)
                {
                    tabPanels[i].SetActive(i == tabIndex);
                }
            }
        }

        if (tabButtons != null)
        {
            for (int i = 0; i < tabButtons.Length; i++)
            {
                if (tabButtons[i] != null)
                {
                    bool isActive = (i == tabIndex);
                    var img = tabButtons[i].GetComponent<Image>();
                    if (img != null)
                    {
                        img.color = isActive
                            ? new Color(0.00f, 0.65f, 0.85f, 0.95f) // Неоновый бирюзовый акцент
                            : new Color(0.06f, 0.10f, 0.16f, 0.85f); // Темный фон неактивной вкладки
                    }

                    var text = tabButtons[i].GetComponentInChildren<Text>();
                    if (text != null)
                    {
                        text.color = isActive
                            ? Color.white
                            : new Color(0.40f, 0.55f, 0.65f, 0.80f);
                    }
                }
            }
        }
    }

    private void SetupTabs()
    {
        if (tabButtons != null)
        {
            for (int i = 0; i < tabButtons.Length; i++)
            {
                int index = i;
                tabButtons[i].onClick.RemoveAllListeners();
                tabButtons[i].onClick.AddListener(() => SwitchTab(index));
            }
        }
    }

    private void SetupActionButtons()
    {
        if (resumeButton != null)
        {
            resumeButton.onClick.RemoveAllListeners();
            resumeButton.onClick.AddListener(ResumeGame);
        }

        if (restartButton != null)
        {
            restartButton.onClick.RemoveAllListeners();
            restartButton.onClick.AddListener(RestartGame);
        }

        if (mainMenuButton != null)
        {
            mainMenuButton.onClick.RemoveAllListeners();
            mainMenuButton.onClick.AddListener(ReturnToMainMenu);
        }

        if (quitButton != null)
        {
            quitButton.onClick.RemoveAllListeners();
            quitButton.onClick.AddListener(QuitGame);
        }
    }

    public void AutoWireUI()
    {
        if (pauseMenuPanel == null)
        {
            var root = transform.Find("PauseRootPanel");
            if (root != null)
            {
                pauseMenuPanel = root.gameObject;
            }
            else
            {
                var panel = transform.Find("PauseMenuPanel");
                if (panel != null) pauseMenuPanel = panel.gameObject;
            }
        }

        Transform window = transform.Find("PauseRootPanel/Settings_Window");
        if (window != null)
        {
            var winRt = window.GetComponent<RectTransform>();
            if (winRt != null && (winRt.sizeDelta.x <= 0f || winRt.sizeDelta.y <= 0f))
            {
                winRt.anchorMin = new Vector2(0.5f, 0.5f);
                winRt.anchorMax = new Vector2(0.5f, 0.5f);
                winRt.pivot = new Vector2(0.5f, 0.5f);
                winRt.anchoredPosition = Vector2.zero;
                winRt.sizeDelta = new Vector2(1100f, 720f);
            }

            Transform dock = window.Find("Bottom_Action_Dock");
            if (dock != null)
            {
                if (resumeButton == null) resumeButton = dock.Find("Btn_Resume")?.GetComponent<Button>();
                if (restartButton == null) restartButton = dock.Find("Btn_Restart")?.GetComponent<Button>();
                if (mainMenuButton == null) mainMenuButton = dock.Find("Btn_MainMenu")?.GetComponent<Button>();
                if (quitButton == null) quitButton = dock.Find("Btn_Quit")?.GetComponent<Button>();
            }

            Transform tabBar = window.Find("Tab_Bar");
            Transform content = window.Find("Content_Area");

            if (tabBar != null && (tabButtons == null || tabButtons.Length == 0))
            {
                tabButtons = new Button[tabBar.childCount];
                for (int i = 0; i < tabBar.childCount; i++)
                {
                    tabButtons[i] = tabBar.GetChild(i).GetComponent<Button>();
                }
            }

            if (content != null && (tabPanels == null || tabPanels.Length == 0))
            {
                tabPanels = new GameObject[]
                {
                    content.Find("Panel_Audio")?.gameObject,
                    content.Find("Panel_Graphics")?.gameObject,
                    content.Find("Panel_Controls")?.gameObject,
                    content.Find("Panel_Briefing")?.gameObject
                };
            }

            if (volumeSlider == null) volumeSlider = content?.Find("Panel_Audio/Row_Volume/Slider")?.GetComponent<Slider>();
            if (volumeValueText == null) volumeValueText = content?.Find("Panel_Audio/Row_Volume/ValueText")?.GetComponent<Text>();
            if (muteToggle == null) muteToggle = content?.Find("Panel_Audio/Row_Mute/Toggle")?.GetComponent<Toggle>();

            if (qualityDropdown == null) qualityDropdown = content?.Find("Panel_Graphics/Row_Quality/Dropdown")?.GetComponent<Dropdown>();
            if (fullscreenToggle == null) fullscreenToggle = content?.Find("Panel_Graphics/Row_Fullscreen/Toggle")?.GetComponent<Toggle>();
            if (resolutionDropdown == null) resolutionDropdown = content?.Find("Panel_Graphics/Row_Resolution/Dropdown")?.GetComponent<Dropdown>();
            if (vsyncToggle == null) vsyncToggle = content?.Find("Panel_Graphics/Row_Vsync/Toggle")?.GetComponent<Toggle>();

            if (sensitivitySlider == null) sensitivitySlider = content?.Find("Panel_Controls/Row_Sensitivity/Slider")?.GetComponent<Slider>();
            if (sensitivityValueText == null) sensitivityValueText = content?.Find("Panel_Controls/Row_Sensitivity/ValueText")?.GetComponent<Text>();
            if (invertYToggle == null) invertYToggle = content?.Find("Panel_Controls/Row_InvertY/Toggle")?.GetComponent<Toggle>();
        }
    }

    private void InitializeSettingsUI()
    {
        isInitializing = true;

        // Звук
        float savedVolume = PlayerPrefs.GetFloat(GameSettings.KeyMasterVolume, 1.0f);
        bool savedMute = PlayerPrefs.GetInt(GameSettings.KeyIsMuted, 0) == 1;

        if (volumeSlider != null)
        {
            volumeSlider.minValue = 0f;
            volumeSlider.maxValue = 1f;
            volumeSlider.value = savedVolume;
            volumeSlider.onValueChanged.RemoveAllListeners();
            volumeSlider.onValueChanged.AddListener(OnVolumeChanged);
        }

        if (muteToggle != null)
        {
            muteToggle.isOn = savedMute;
            muteToggle.onValueChanged.RemoveAllListeners();
            muteToggle.onValueChanged.AddListener(OnMuteChanged);
        }

        UpdateVolumeLabel(savedVolume, savedMute);

        // Качество графики
        if (qualityDropdown != null)
        {
            qualityDropdown.ClearOptions();
            List<string> options = new List<string>();
            foreach (var q in QualitySettings.names)
            {
                options.Add(TranslateQuality(q));
            }
            qualityDropdown.AddOptions(options);
            qualityDropdown.value = PlayerPrefs.GetInt(GameSettings.KeyQualityLevel, QualitySettings.GetQualityLevel());
            qualityDropdown.RefreshShownValue();
            qualityDropdown.onValueChanged.RemoveAllListeners();
            qualityDropdown.onValueChanged.AddListener(OnQualityChanged);
        }

        // Полноэкранный режим
        if (fullscreenToggle != null)
        {
            fullscreenToggle.isOn = PlayerPrefs.GetInt(GameSettings.KeyFullscreen, Screen.fullScreen ? 1 : 0) == 1;
            fullscreenToggle.onValueChanged.RemoveAllListeners();
            fullscreenToggle.onValueChanged.AddListener(OnFullscreenChanged);
        }

        // Разрешения экрана
        PopulateResolutions();

        // Вертикальная синхронизация
        if (vsyncToggle != null)
        {
            vsyncToggle.isOn = QualitySettings.vSyncCount > 0;
            vsyncToggle.onValueChanged.RemoveAllListeners();
            vsyncToggle.onValueChanged.AddListener(OnVsyncChanged);
        }

        // Чувствительность
        float savedSens = PlayerPrefs.GetFloat(GameSettings.KeyMouseSensitivity, 1.0f);
        if (sensitivitySlider != null)
        {
            sensitivitySlider.minValue = 0.2f;
            sensitivitySlider.maxValue = 3.0f;
            sensitivitySlider.value = savedSens;
            sensitivitySlider.onValueChanged.RemoveAllListeners();
            sensitivitySlider.onValueChanged.AddListener(OnSensitivityChanged);
        }

        UpdateSensitivityLabel(savedSens);

        // Инверсия по Y
        if (invertYToggle != null)
        {
            invertYToggle.isOn = PlayerPrefs.GetInt("Settings_InvertY", 0) == 1;
            invertYToggle.onValueChanged.RemoveAllListeners();
            invertYToggle.onValueChanged.AddListener(OnInvertYChanged);
        }

        isInitializing = false;
    }

    private void PopulateResolutions()
    {
        if (resolutionDropdown == null) return;

        resolutionDropdown.ClearOptions();
        var allRes = Screen.resolutions;
        filteredResolutions.Clear();
        var options = new List<string>();
        var seen = new HashSet<string>();

        for (int i = allRes.Length - 1; i >= 0; i--)
        {
            var res = allRes[i];
            string key = $"{res.width}x{res.height}";
            if (!seen.Contains(key))
            {
                seen.Add(key);
                filteredResolutions.Insert(0, res);
            }
        }

        if (filteredResolutions.Count == 0)
        {
            filteredResolutions.Add(new Resolution { width = 1920, height = 1080 });
            filteredResolutions.Add(new Resolution { width = 1280, height = 720 });
        }

        int currentIdx = 0;
        int curW = Screen.width;
        int curH = Screen.height;

        for (int i = 0; i < filteredResolutions.Count; i++)
        {
            var r = filteredResolutions[i];
            options.Add($"{r.width} x {r.height}");
            if (r.width == curW && r.height == curH)
            {
                currentIdx = i;
            }
        }

        resolutionDropdown.AddOptions(options);
        resolutionDropdown.value = currentIdx;
        resolutionDropdown.RefreshShownValue();
        resolutionDropdown.onValueChanged.RemoveAllListeners();
        resolutionDropdown.onValueChanged.AddListener(OnResolutionChanged);
    }

    private void OnResolutionChanged(int index)
    {
        if (isInitializing || index < 0 || index >= filteredResolutions.Count) return;
        var r = filteredResolutions[index];
        bool isFull = fullscreenToggle != null ? fullscreenToggle.isOn : Screen.fullScreen;
        Screen.SetResolution(r.width, r.height, isFull);
        PlayerPrefs.SetInt(GameSettings.KeyResolutionWidth, r.width);
        PlayerPrefs.SetInt(GameSettings.KeyResolutionHeight, r.height);
    }

    private void OnVsyncChanged(bool enabled)
    {
        if (isInitializing) return;
        QualitySettings.vSyncCount = enabled ? 1 : 0;
    }

    private void OnInvertYChanged(bool enabled)
    {
        if (isInitializing) return;
        PlayerPrefs.SetInt("Settings_InvertY", enabled ? 1 : 0);
    }

    private void OnVolumeChanged(float val)
    {
        if (isInitializing) return;
        PlayerPrefs.SetFloat(GameSettings.KeyMasterVolume, val);
        bool isMuted = muteToggle != null && muteToggle.isOn;
        if (!isMuted) AudioListener.volume = val;
        UpdateVolumeLabel(val, isMuted);
    }

    private void OnMuteChanged(bool isMuted)
    {
        if (isInitializing) return;
        PlayerPrefs.SetInt(GameSettings.KeyIsMuted, isMuted ? 1 : 0);
        float currentVol = volumeSlider != null ? volumeSlider.value : 1.0f;
        AudioListener.volume = isMuted ? 0f : currentVol;
        UpdateVolumeLabel(currentVol, isMuted);
    }

    private void UpdateVolumeLabel(float vol, bool muted)
    {
        if (volumeValueText != null)
        {
            volumeValueText.text = muted ? "ВЫКЛ" : $"{Mathf.RoundToInt(vol * 100)}%";
        }
    }

    private void OnQualityChanged(int index)
    {
        if (isInitializing) return;
        QualitySettings.SetQualityLevel(index, true);
        PlayerPrefs.SetInt(GameSettings.KeyQualityLevel, index);
    }

    private void OnFullscreenChanged(bool isFullscreen)
    {
        if (isInitializing) return;
        Screen.fullScreen = isFullscreen;
        PlayerPrefs.SetInt(GameSettings.KeyFullscreen, isFullscreen ? 1 : 0);
    }

    private void OnSensitivityChanged(float val)
    {
        if (isInitializing) return;
        PlayerPrefs.SetFloat(GameSettings.KeyMouseSensitivity, val);
        UpdateSensitivityLabel(val);
    }

    private void UpdateSensitivityLabel(float val)
    {
        if (sensitivityValueText != null)
        {
            sensitivityValueText.text = $"{val:F1}x";
        }
    }

    private string TranslateQuality(string q)
    {
        switch (q.ToLower())
        {
            case "very low": return "Очень низкое";
            case "low": return "Низкое";
            case "medium": return "Среднее";
            case "high": return "Высокое";
            case "very high": return "Очень высокое";
            case "ultra": return "Ультра";
            default: return q;
        }
    }
}