using UnityEngine;
using UnityEngine.UIElements;

public class BuildingUIController : MonoBehaviour
{
    [Header("UI References")]
    public UIDocument uiDocument;

    [Header("Building System")]
    public NewRoomBuilder roomBuilder;

    private VisualElement root;
    private Button wallModeButton;
    private Button doorModeButton;
    private Button entranceModeButton;
    private Button normalModeButton;
    private Label statusLabel;
    private Label instructionLabel;

    public enum BuildingMode
    {
        Normal,
        CreatingWalls,
        CreatingDoors,
        CreatingEntrance
    }

    private BuildingMode currentMode = BuildingMode.Normal;

    private void Start()
    {
        InitializeUI();

        // Check for existing entrances periodically
        InvokeRepeating(nameof(UpdateEntranceButtonVisibility), 1f, 1f);
    }

    private void InitializeUI()
    {
        if (uiDocument == null)
        {
            uiDocument = GetComponent<UIDocument>();
        }

        // Load the UXML file
        VisualTreeAsset uiAsset = Resources.Load<VisualTreeAsset>("UI/BuildingInterface");
        if (uiAsset == null)
        {
            // Try loading from Assets/UI folder
            uiAsset = UnityEngine.Resources.Load<VisualTreeAsset>("BuildingInterface");
        }

        if (uiAsset != null)
        {
            uiDocument.visualTreeAsset = uiAsset;
        }
        else
        {
            Debug.LogWarning("BuildingInterface.uxml not found. Creating UI programmatically.");
            CreateUIManually();
            return;
        }

        root = uiDocument.rootVisualElement;

        // Get button references
        wallModeButton = root.Q<Button>("WallModeButton");
        doorModeButton = root.Q<Button>("DoorModeButton");
        entranceModeButton = root.Q<Button>("EntranceModeButton");
        normalModeButton = root.Q<Button>("NormalModeButton");

        // Get label references
        statusLabel = root.Q<Label>("StatusLabel");
        instructionLabel = root.Q<Label>("InstructionLabel");

        // Register button callbacks
        if (wallModeButton != null) wallModeButton.clicked += OnWallModeClicked;
        if (doorModeButton != null) doorModeButton.clicked += OnDoorModeClicked;
        if (entranceModeButton != null) entranceModeButton.clicked += OnEntranceModeClicked;
        if (normalModeButton != null) normalModeButton.clicked += OnNormalModeClicked;

        // Initialize UI state
        UpdateUI();
    }

    private void CreateUIManually()
    {
        // Create UI elements manually if UXML file is not found
        root = uiDocument.rootVisualElement;

        // Create main panel
        VisualElement panel = new VisualElement();
        panel.name = "BuildingPanel";
        panel.style.position = Position.Absolute;
        panel.style.top = 20;
        panel.style.left = 20;
        panel.style.minWidth = 200;
        panel.style.backgroundColor = new Color(0, 0, 0, 0.8f);
        panel.style.paddingTop = panel.style.paddingLeft = panel.style.paddingRight = panel.style.paddingBottom = 15;

        // Create title
        Label title = new Label("Building Tools");
        title.name = "Title";
        title.style.fontSize = 18;
        title.style.color = Color.white;
        title.style.unityFontStyleAndWeight = FontStyle.Bold;
        title.style.marginBottom = 10;
        panel.Add(title);

        // Create buttons
        wallModeButton = new Button(() => OnWallModeClicked()) { text = "Create Walls" };
        doorModeButton = new Button(() => OnDoorModeClicked()) { text = "Create Doors" };
        entranceModeButton = new Button(() => OnEntranceModeClicked()) { text = "Create Entrance" };
        normalModeButton = new Button(() => OnNormalModeClicked()) { text = "Normal Mode" };

        wallModeButton.style.marginBottom = doorModeButton.style.marginBottom = entranceModeButton.style.marginBottom = normalModeButton.style.marginBottom = 8;
        wallModeButton.style.minHeight = doorModeButton.style.minHeight = entranceModeButton.style.minHeight = normalModeButton.style.minHeight = 35;

        panel.Add(wallModeButton);
        panel.Add(doorModeButton);
        panel.Add(entranceModeButton);
        panel.Add(normalModeButton);

        // Create status labels
        statusLabel = new Label("Mode: Normal");
        instructionLabel = new Label("Click a button to start building");

        statusLabel.style.fontSize = 14;
        statusLabel.style.color = new Color(0.8f, 1f, 0.8f);
        statusLabel.style.unityFontStyleAndWeight = FontStyle.Bold;
        statusLabel.style.marginTop = 10;
        statusLabel.style.marginBottom = 5;

        instructionLabel.style.fontSize = 12;
        instructionLabel.style.color = new Color(0.8f, 0.8f, 0.8f);
        instructionLabel.style.whiteSpace = WhiteSpace.Normal;

        panel.Add(statusLabel);
        panel.Add(instructionLabel);

        root.Add(panel);

        UpdateUI();
    }

    private void OnWallModeClicked()
    {
        SetBuildingMode(BuildingMode.CreatingWalls);
    }

    private void OnDoorModeClicked()
    {
        SetBuildingMode(BuildingMode.CreatingDoors);
    }

    private void OnEntranceModeClicked()
    {
        SetBuildingMode(BuildingMode.CreatingEntrance);
    }

    private void OnNormalModeClicked()
    {
        SetBuildingMode(BuildingMode.Normal);
    }

    public void SetBuildingMode(BuildingMode mode)
    {
        currentMode = mode;

        // Notify the room builder of the mode change
        if (roomBuilder != null)
        {
            roomBuilder.SetBuildingMode(mode);
        }

        UpdateUI();
    }

    private void UpdateUI()
    {
        // Update entrance button visibility first
        UpdateEntranceButtonVisibility();

        // Remove active class from all buttons
        wallModeButton.RemoveFromClassList("active");
        doorModeButton.RemoveFromClassList("active");
        if (entranceModeButton != null) entranceModeButton.RemoveFromClassList("active");
        normalModeButton.RemoveFromClassList("active");

        // Update button states and labels based on current mode
        switch (currentMode)
        {
            case BuildingMode.Normal:
                normalModeButton.AddToClassList("active");
                statusLabel.text = "Mode: Normal";
                instructionLabel.text = "Click a button to start building";
                break;

            case BuildingMode.CreatingWalls:
                wallModeButton.AddToClassList("active");
                statusLabel.text = "Mode: Creating Walls";
                instructionLabel.text = "Click and drag to create walls. Walls snap to 45° angles.";
                break;

            case BuildingMode.CreatingDoors:
                doorModeButton.AddToClassList("active");
                statusLabel.text = "Mode: Creating Doors";
                instructionLabel.text = "Click on a wall to add a door opening.";
                break;

            case BuildingMode.CreatingEntrance:
                if (entranceModeButton != null) entranceModeButton.AddToClassList("active");
                statusLabel.text = "Mode: Creating Entrance";
                instructionLabel.text = "Click on an outer wall to create the main building entrance.";
                break;
        }
    }

    public BuildingMode GetCurrentMode()
    {
        return currentMode;
    }

    private void UpdateEntranceButtonVisibility()
    {
        if (entranceModeButton == null) return;

        // Check if an entrance exists
        GameObject[] existingEntrances = GameObject.FindGameObjectsWithTag("Entrance");
        bool hasEntrance = existingEntrances != null && existingEntrances.Length > 0;

        // Show/hide the entrance button based on whether an entrance exists
        entranceModeButton.style.display = hasEntrance ? DisplayStyle.None : DisplayStyle.Flex;

        // If we're in entrance creation mode and an entrance was just created, switch to normal mode
        if (hasEntrance && currentMode == BuildingMode.CreatingEntrance)
        {
            SetBuildingMode(BuildingMode.Normal);
        }
    }

    private void OnDestroy()
    {
        // Clean up the repeating invocation
        CancelInvoke(nameof(UpdateEntranceButtonVisibility));
    }
}