using UnityEngine;
using EnhancedUI;
using EnhancedUI.EnhancedScroller;

/// <summary>
/// Set up our demo script as a delegate for the scroller by inheriting from the IEnhancedScrollerDelegate interface
/// 
/// EnhancedScroller delegates will handle telling the scroller:
///  - How many cells it should allocate room for (GetNumberOfCells)
///  - What each cell size is (GetCellSize)
///  - What the cell at a given index should be (GetCell)
/// </summary>
public class EScrController : MonoBehaviour, IEnhancedScrollerDelegate
{
    /// <summary>
    /// Internal representation of our data. Note that the scroller will never see
    /// this, so it separates the data from the layout using MVC principles.
    /// </summary>
    private SmallList<int> _data;
    protected int iType = -1;

    /// <summary>
    /// This is our scroller we will be a delegate for
    /// </summary>
    public EnhancedScroller scroller;

    /// <summary>
    /// This will be the prefab of each cell in our scroller. Note that you can use more
    /// than one kind of cell, but this example just has the one type.
    /// </summary>
    [SerializeField]
    protected EnhancedScrollerCellView cellViewPrefab;
    protected float fSize = 100f;

    /// <summary>
    /// Be sure to set up your references to the scroller after the Awake function. The 
    /// scroller does some internal configuration in its own Awake function. If you need to
    /// do this in the Awake function, you can set up the script order through the Unity editor.
    /// In this case, be sure to set the EnhancedScroller's script before your delegate.
    /// 
    /// In this example, we are calling our initializations in the delegate's Start function,
    /// but it could have been done later, perhaps in the Update function.
    /// </summary>
    protected void Start()
    {
        // tell the scroller that this script will be its delegate
        scroller.Delegate = this;
        if (scroller.scrollDirection == EnhancedScroller.ScrollDirectionEnum.Vertical)
        {
            fSize = cellViewPrefab.GetComponent<RectTransform>().sizeDelta.y;
        }
        else
        {
            fSize = cellViewPrefab.GetComponent<RectTransform>().sizeDelta.x;
        }
    }

    public void SetType(int itype)
    {
        iType = itype;

        int icnt = scroller.GetCellViewsCount();
        for (int i = 0; i < icnt; i++)
            (scroller.GetCellViewsAtCellIndex(i) as EScrCell).SetType(itype);
    }

    public void ReleaseResources()
    {
        int icnt = scroller.GetCellViewsCount();
        for (int i = 0; i < icnt; i++)
            scroller.GetCellViewsAtCellIndex(i).ReleaseResources();
    }

    public void Localize()
    {
        int icnt = scroller.GetCellViewsCount();
        for (int i = 0; i < icnt; i++)
            scroller.GetCellViewsAtCellIndex(i).Localize();
    }

    public void SetFloat(float fvalue)
    {
        int icnt = scroller.GetCellViewsCount();
        for (int i = 0; i < icnt; i++)
            scroller.GetCellViewsAtCellIndex(i).SetFloat(fvalue);
    }

    object intent;
    public void LoadDatas(SmallList<int> datalist)
    {
        intent = null;
        _data = datalist;
        scroller.ReloadData();
    }

    public void LoadDatas(SmallList<int> datalist, object intent)
    {
        this.intent = intent;
        _data = datalist;
        scroller.ReloadData();
    }

    #region EnhancedScroller Handlers
    /// <summary>
    /// This tells the scroller the number of cells that should have room allocated. This should be the length of your data array.
    /// </summary>
    /// <param name="scroller">The scroller that is requesting the data size</param>
    /// <returns>The number of cells</returns>
    public int GetNumberOfCells(EnhancedScroller scroller)
    {
        if (_data == null)
            return 0;
        // in this example, we just pass the number of our data elements
        return _data.Count;
    }

    /// <summary>
    /// This tells the scroller what the size of a given cell will be. Cells can be any size and do not have
    /// to be uniform. For vertical scrollers the cell size will be the height. For horizontal scrollers the
    /// cell size will be the width.
    /// </summary>
    /// <param name="scroller">The scroller requesting the cell size</param>
    /// <param name="dataIndex">The index of the data that the scroller is requesting</param>
    /// <returns>The size of the cell</returns>
    public float GetCellViewSize(EnhancedScroller scroller, int dataIndex)
    {
        return fSize;
    }

    /// <summary>
    /// Gets the cell to be displayed. You can have numerous cell types, allowing variety in your list.
    /// Some examples of this would be headers, footers, and other grouping cells.
    /// </summary>
    /// <param name="scroller">The scroller requesting the cell</param>
    /// <param name="dataIndex">The index of the data that the scroller is requesting</param>
    /// <param name="cellIndex">The index of the list. This will likely be different from the dataIndex if the scroller is looping</param>
    /// <returns>The cell for the scroller to use</returns>
    public EnhancedScrollerCellView GetCellView(EnhancedScroller scroller, int dataIndex, int cellIndex)
    {
        // first, we get a cell from the scroller by passing a prefab.
        // if the scroller finds one it can recycle it will do so, otherwise
        // it will create a new cell.
        EScrCell cellview = scroller.GetCellView(cellViewPrefab) as EScrCell;

        // set the name of the game object to the cell's data index.
        // this is optional, but it helps up debug the objects in 
        // the scene hierarchy.
        cellview.name = FormatString.StringFormat("Cell{0:0000}", dataIndex);
        cellview.SetType(iType);

        // in this example, we just pass the data to our cell's view which will update its UI
        if(intent != null && cellview is IOnRecieveIntent reciever)
            reciever.OnRecieveIntent(intent);

        cellview.SetData(_data[dataIndex]);

        // return the cell to the scroller
        return cellview;
    }
    #endregion
}