using System.Collections.Generic;
using TMPro;
using UnityEngine;
using UnityEngine.UI;

/// <summary>
/// The pose selection menu (the "Pose UI" canvas in Main): a modal pause overlay (same pattern as
/// <see cref="MatchResultScreen"/>) opened via the overview menu's Pose button, closed by Esc through
/// <see cref="OverviewMenu"/> (all Esc handling lives there). On every open it rebuilds a radial menu
/// of Icon Button prefab instances from the local player's <see cref="PlayerPoseController.Poses"/>
/// (icon + title come from each <see cref="PlayerPose"/>); clicking an item applies that pose and
/// closes the menu. The active pose's button is disabled (its hover ring marks it, like the overview
/// menu's mode buttons). Only the visual <see cref="panelRoot"/> is toggled - this binder stays alive
/// on its (always-active) canvas root.
/// </summary>
[DisallowMultipleComponent]
public class PoseMenu : MonoBehaviour
{
    [Tooltip("Mode manager supplying the local player (whose PlayerPoseController is driven) and the " +
             "pause hook. Empty = found automatically.")]
    [SerializeField] private GameModeManager gameMode;

    [Header("Overlay")]
    [Tooltip("Visual container toggled via Open/Close. Must be a CHILD of this binder's object so the " +
             "binder stays alive while the panel is hidden.")]
    [SerializeField] private GameObject panelRoot;

    [Header("Radial menu")]
    [Tooltip("Center the pose items are arranged around (typically a centered child of the panel).")]
    [SerializeField] private RectTransform itemContainer;

    [Tooltip("Icon Button prefab instantiated per pose (Icon child image + Label child TMP are bound).")]
    [SerializeField] private GameObject itemPrefab;

    [Tooltip("Distance of each item from the container center, in canvas units.")]
    [Min(0f)]
    [SerializeField] private float radius = 220f;

    private readonly List<GameObject> _items = new();
    private PlayerPoseController _poseController; // controller the open menu is bound to
    private bool _open;

    private void Awake()
    {
        if (!gameMode) gameMode = FindFirstObjectByType<GameModeManager>();
        if (panelRoot) panelRoot.SetActive(false);
    }

    /// <summary>True while the modal overlay is open. The overview menu yields Esc to this overlay
    /// (close-only) while it is open.</summary>
    public bool IsOpen => _open;

    /// <summary>True while the local player has selectable poses - the overview menu hides its Pose
    /// button otherwise (no player bound, or an empty pose list).</summary>
    public bool CanOpen => LocalPoseController() && LocalPoseController().Poses.Count > 0;

    /// <summary>With 2 or fewer poses (the hunter's set) a radial menu is pointless - the pose button
    /// and the C hotkey cycle directly via <see cref="CyclePose"/> instead of opening the overlay.</summary>
    public bool CyclesDirectly
    {
        get
        {
            PlayerPoseController pose = LocalPoseController();
            return pose && pose.Poses.Count > 0 && pose.Poses.Count <= 2;
        }
    }

    /// <summary>Advances to the next pose (wrapping) without opening the overlay.</summary>
    public void CyclePose()
    {
        PlayerPoseController pose = LocalPoseController();
        if (pose && pose.Poses.Count > 0) pose.SetPoseIndex(pose.CurrentIndex + 1);
    }

    /// <summary>Opens the modal overlay and (re)builds the radial items; false when there is nothing
    /// to show, so the caller can drop the pause instead of stranding it.</summary>
    public bool Open()
    {
        PlayerPoseController pose = LocalPoseController();
        if (!pose || pose.Poses.Count == 0 || !itemContainer || !itemPrefab) return false;
        _poseController = pose;
        BuildItems(pose);
        _open = true;
        if (panelRoot) panelRoot.SetActive(true);
        if (gameMode) gameMode.SetPaused(true);
        return true;
    }

    /// <summary>Closes the modal overlay and resumes gameplay (Esc handling in <see cref="OverviewMenu"/>).</summary>
    public void Close()
    {
        _open = false;
        if (panelRoot) panelRoot.SetActive(false);
        if (gameMode) gameMode.SetPaused(false);
    }

    private void Update()
    {
        // The bound player went away underneath the open menu (despawn/disconnect) -> don't linger
        // as a stale pause overlay.
        if (_open && !_poseController)
            Close();
    }

    private PlayerPoseController LocalPoseController()
    {
        PlayerCharacterController player = gameMode ? gameMode.Player : null;
        return player ? player.GetComponent<PlayerPoseController>() : null;
    }

    /// <summary>Instantiates one Icon Button per pose, evenly on a circle starting at 12 o'clock going
    /// clockwise. Rebuilt on every open - pose count is tiny and the list can differ per bound player.</summary>
    private void BuildItems(PlayerPoseController pose)
    {
        for (int i = 0; i < _items.Count; i++)
            if (_items[i]) Destroy(_items[i]);
        _items.Clear();

        IReadOnlyList<PlayerPose> poses = pose.Poses;
        for (int i = 0; i < poses.Count; i++)
        {
            GameObject item = Instantiate(itemPrefab, itemContainer);
            float angle = (90f - i * 360f / poses.Count) * Mathf.Deg2Rad;
            ((RectTransform)item.transform).anchoredPosition =
                new Vector2(Mathf.Cos(angle), Mathf.Sin(angle)) * radius;

            PlayerPose p = poses[i];
            Transform iconChild = item.transform.Find("Icon");
            Image icon = iconChild ? iconChild.GetComponent<Image>() : null;
            if (icon)
            {
                icon.sprite = p ? p.Icon : null;
                icon.preserveAspect = true;
                icon.enabled = icon.sprite; // no icon authored -> no solid white square
                icon.rectTransform.localScale = Vector3.one * (p ? p.IconScale : 1f);
            }
            TMP_Text label = item.GetComponentInChildren<TMP_Text>(true);
            if (label) label.text = p && !string.IsNullOrEmpty(p.Title) ? p.Title : (p ? p.name : "");

            Button button = item.GetComponent<Button>();
            if (button)
            {
                int index = i;
                button.onClick.AddListener(() => OnItem(index));
                // Disabled = current pose; its hover ring (IconButtonHover) marks it as active.
                button.interactable = pose.CurrentIndex != i;
            }
            _items.Add(item);
        }
    }

    private void OnItem(int index)
    {
        if (_poseController) _poseController.SetPoseIndex(index);
        Close();
    }
}