using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using KairoEngine.UI;
using KairoEngine.UI.InteractionHandler;
using KairoEngine.UI.Tooltips;

namespace KairoEngine.GameTools.Selectables
{
    /// <summary>
    /// A UI component that shows the actions for a given selected object or objects. 
    /// </summary>
    public class SelectionActionsView : MonoBehaviour, IUiSystemElement, IClickHandler
    {
        public bool hideWhenEmpty = true;
        public SelectableObjectTool selectableObjectTool;
        public GameObject panel;
        public RectTransform container;
        public GameObject actionButtonPrefab;

        private List<SelectableObjectAction> actions = new List<SelectableObjectAction>();
        private List<GameObject> buttons = new List<GameObject>();
        private bool hidden = false;

        private void Start()
        {
            if(actionButtonPrefab == null) Debug.LogError("Missing Action Button Prefab in SelectionActionsView", this.gameObject);
            if(container == null) Debug.LogError("Missing container in SelectionActionsView", this.gameObject);   
            UiManager.RegisterElement("SelectionActions", this, this.transform, true);
            if(hideWhenEmpty) panel.SetActive(false);
        }

        private void Update()
        {
            if(selectableObjectTool.ActionListChanged())
            {
                actions = selectableObjectTool.GetActions();
                UpdateActionButtons();
            }
            if(!hidden)
            {
                if(actions.Count == 0 && hideWhenEmpty) panel.SetActive(false);
                else panel.SetActive(true);
            }
            else panel.SetActive(false);
        }

        public void Hide()
        {
            hidden = true;
            panel.SetActive(false);
        }

        public bool IsVisible()
        {
            return panel.activeSelf;
        }

        public void Show()
        {
            hidden = false;
            panel.SetActive(true);
        }

        private void UpdateActionButtons()
        {
            for (int i = 0; i < buttons.Count; i++)
            {
                Destroy(buttons[i].gameObject);
            }
            buttons = new List<GameObject>();
            if(actionButtonPrefab == null || container == null) return;
            for (int i = 0; i < actions.Count; i++)
            {
                var obj = Instantiate(actionButtonPrefab, container);
                buttons.Add(obj);
                ClickHandler handler = obj.GetComponent<ClickHandler>();
                if(handler != null)
                {
                    handler.title = actions[i].title;
                    handler.receiver = this;
                }
                ButtonData buttonData = obj.GetComponent<ButtonData>();
                if(buttonData != null) buttonData.Setup(actions[i].title, actions[i].icon);
                TooltipTrigger tooltip = obj.GetComponent<TooltipTrigger>();
                if(tooltip != null) 
                {
                    tooltip.header = actions[i].title;
                    tooltip.content = actions[i].description;
                }
            }
            
        }

        public void OnClick(string title)
        {
            for (int i = 0; i < actions.Count; i++)
            {
                if(actions[i].title == title) 
                {
                    selectableObjectTool.ExecuteAction(actions[i]);
                    return;
                }
            }
        }
    }
}