using UnityEngine;
using UnityEngine.UIElements;
using System.Collections.Generic;
using System.Linq;

/// <summary>
/// Displays active fights in the UI with zoom buttons
/// Shows runner vs monster fights, sorted by fight intensity (participants in room)
/// </summary>
public class ActiveFightsUIPanel : MonoBehaviour
{
    [Header("Settings")]
    [SerializeField] private float updateInterval = 0.5f;

    private VisualElement root;
    private VisualElement fightsList;
    private Dictionary<string, VisualElement> fightEntries = new();
    private float lastUpdateTime = 0f;

    void Start()
    {
        InitializeUI();
    }

    private void InitializeUI()
    {
        // Find or create UIDocument
        var uiDocument = FindAnyObjectByType<UIDocument>();
        if (uiDocument == null)
        {
            var docGO = new GameObject("UIDocument");
            uiDocument = docGO.AddComponent<UIDocument>();
        }

        root = uiDocument.rootVisualElement;

        // Create the fights panel container
        var panelContainer = new VisualElement();
        panelContainer.name = "ActiveFightsPanel";
        panelContainer.style.position = Position.Absolute;
        panelContainer.style.left = 20;  // Left side instead of right
        panelContainer.style.top = 20;
        panelContainer.style.width = 350;
        // Limit height so the list scrolls instead of growing off-screen
        panelContainer.style.maxHeight = new StyleLength(new Length(85, LengthUnit.Percent));
        panelContainer.style.backgroundColor = new Color(0.1f, 0.1f, 0.1f, 0.8f);
        panelContainer.style.borderBottomLeftRadius = 5;
        panelContainer.style.borderBottomRightRadius = 5;
        panelContainer.style.borderTopLeftRadius = 5;
        panelContainer.style.borderTopRightRadius = 5;
        panelContainer.style.paddingBottom = 10;
        panelContainer.style.paddingTop = 10;
        panelContainer.style.paddingLeft = 10;
        panelContainer.style.paddingRight = 10;
        panelContainer.style.flexDirection = FlexDirection.Column;

        // Title
        var title = new Label("Active Fights");
        title.style.fontSize = 16;
        title.style.color = Color.white;
        title.style.marginBottom = 10;
        title.style.unityFontStyleAndWeight = FontStyle.Bold;
        title.style.flexShrink = 0;
        panelContainer.Add(title);

        // Scrollable container so the list doesn't overflow the screen
        var scrollView = new ScrollView(ScrollViewMode.Vertical);
        scrollView.name = "FightsScrollView";
        scrollView.style.flexGrow = 1;
        scrollView.style.flexShrink = 1;
        scrollView.horizontalScrollerVisibility = ScrollerVisibility.Hidden;
        scrollView.verticalScrollerVisibility = ScrollerVisibility.Auto;

        // Fights list container (lives inside the ScrollView)
        fightsList = new VisualElement();
        fightsList.name = "FightsList";
        fightsList.style.flexDirection = FlexDirection.Column;
        scrollView.Add(fightsList);

        panelContainer.Add(scrollView);

        root.Add(panelContainer);
    }

    void Update()
    {
        if (FightTracker.Instance == null) return;
        if (fightsList == null) return;
        if (Time.time - lastUpdateTime < updateInterval) return;
        lastUpdateTime = Time.time;

        RefreshFightsList();
    }

    /// <summary>
    /// Updates the list of displayed fights
    /// </summary>
    private void RefreshFightsList()
    {
        var fights = FightTracker.Instance.GetDisplayFights();
        var currentFightIds = new HashSet<string>();

        // Update or create entries for current fights
        foreach (var fight in fights)
        {
            string fightId = $"{fight.runnerId}_{fight.monster.GetHashCode()}";
            currentFightIds.Add(fightId);

            if (fightEntries.ContainsKey(fightId))
            {
                // Update existing entry
                UpdateFightEntry(fightEntries[fightId], fight);
            }
            else
            {
                // Create new entry
                var entryElement = CreateFightEntry(fight, fightId);
                fightEntries[fightId] = entryElement;
                fightsList.Add(entryElement);
            }
        }

        // Remove entries for fights that are no longer active
        var entriesToRemove = fightEntries.Keys.Where(id => !currentFightIds.Contains(id)).ToList();
        foreach (var id in entriesToRemove)
        {
            if (fightEntries[id] != null)
            {
                fightEntries[id].RemoveFromHierarchy();
            }
            fightEntries.Remove(id);
        }
    }

    /// <summary>
    /// Creates a single fight entry UI element
    /// </summary>
    private VisualElement CreateFightEntry(FightData fight, string fightId)
    {
        var entryContainer = new VisualElement();
        entryContainer.name = $"FightEntry_{fightId}";
        entryContainer.style.flexDirection = FlexDirection.Row;
        entryContainer.style.backgroundColor = new Color(0.2f, 0.2f, 0.2f, 0.9f);
        entryContainer.style.borderBottomLeftRadius = 3;
        entryContainer.style.borderBottomRightRadius = 3;
        entryContainer.style.borderTopLeftRadius = 3;
        entryContainer.style.borderTopRightRadius = 3;
        entryContainer.style.paddingBottom = 5;
        entryContainer.style.paddingTop = 5;
        entryContainer.style.paddingLeft = 8;
        entryContainer.style.paddingRight = 8;
        entryContainer.style.marginBottom = 5;
        entryContainer.style.alignItems = Align.Center;

        // Status indicator
        var statusDot = new VisualElement();
        statusDot.style.width = 12;
        statusDot.style.height = 12;
        statusDot.style.borderBottomLeftRadius = 6;
        statusDot.style.borderBottomRightRadius = 6;
        statusDot.style.borderTopLeftRadius = 6;
        statusDot.style.borderTopRightRadius = 6;
        statusDot.style.backgroundColor = fight.isActive ? Color.red : new Color(1f, 0.5f, 0f);
        statusDot.style.marginRight = 8;
        entryContainer.Add(statusDot);

        // Fight text
        var fightText = new Label(fight.GetDisplayText());
        fightText.style.color = Color.white;
        fightText.style.fontSize = 12;
        fightText.style.flexGrow = 1;
        entryContainer.Add(fightText);

        // Zoom button
        var zoomButton = new Button(() => ZoomToFight(fight));
        zoomButton.text = "Zoom";
        zoomButton.style.width = 60;
        zoomButton.style.height = 25;
        zoomButton.style.backgroundColor = new Color(0.2f, 0.5f, 0.9f, 0.9f);
        zoomButton.style.color = Color.white;
        zoomButton.style.fontSize = 11;
        zoomButton.style.marginLeft = 8;
        entryContainer.Add(zoomButton);

        return entryContainer;
    }

    /// <summary>
    /// Updates an existing fight entry
    /// </summary>
    private void UpdateFightEntry(VisualElement entryElement, FightData fight)
    {
        if (entryElement == null) return;

        // Update status dot color
        var statusDot = entryElement.Q<VisualElement>(null, "unity-content-container")?.Children().FirstOrDefault() as VisualElement;
        if (statusDot != null)
        {
            statusDot.style.backgroundColor = fight.isActive ? Color.red : new Color(1f, 0.5f, 0f);
        }
    }

    /// <summary>
    /// Zooms the camera to the room where the fight is happening
    /// </summary>
    private void ZoomToFight(FightData fight)
    {
        var cameraController = FindAnyObjectByType<MazeCameraController>();
        if (cameraController != null)
        {
            cameraController.ZoomToRoom(fight.room, 1.3f, 0.5f);
        }
    }
}