using ComPDFKitViewer;
using ComPDFKitViewer.PdfViewer;
using Microsoft.Office.Core;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace PDF_Office.Helper
{
    public enum CropPageEnum
    {
        CropCurrentPageWM,
        CropAllPagesWM
    }

    public class CropPageUndoManager : IHistory
    {
        public List<int> cropPageList = new List<int>();

        private List<CropPageEnum> cropPageEnumList = new List<CropPageEnum>();

        private int cropPageEnumIndex = -1;

        private int cropPageListInterval = 0;

        private CPDFViewer pdfviewer = null;

        public CropPageUndoManager()
        {

        }

        public void setPDFViewer(CPDFViewer pDFViewer)
        {
            pdfviewer = pDFViewer;
        }

        public void ADDCropCurrentPageWM()
        {
            cropPageEnumIndex++;
            cropPageEnumList.Insert(cropPageEnumIndex, CropPageEnum.CropCurrentPageWM);
            if (cropPageEnumIndex != cropPageEnumList.Count - 1)
            {
                cropPageEnumList.RemoveRange(cropPageEnumIndex + 1, cropPageEnumList.Count - cropPageEnumIndex-1);
                cropPageList.RemoveRange(cropPageList.Count - cropPageListInterval-1, cropPageListInterval);
                cropPageListInterval = 0;
            }



        }
        public void ADDCropAllPagesWM()
        {
            cropPageEnumIndex++;
            cropPageEnumList.Insert(cropPageEnumIndex, CropPageEnum.CropAllPagesWM);
            if (cropPageEnumIndex != cropPageEnumList.Count - 1)
            {
                cropPageEnumList.RemoveRange(cropPageEnumIndex+1, cropPageEnumList.Count - cropPageEnumIndex-1);
                cropPageList.RemoveRange(cropPageList.Count - cropPageListInterval-37, cropPageListInterval);
                cropPageListInterval = 0;
            }
            
        }

        public void setPageList(List<int> CropPageList)
        {
            cropPageList = CropPageList;
        }

        public bool Redo()
        {
            cropPageEnumIndex++;
            if (cropPageEnumIndex < cropPageEnumList.Count )
            {
                
                if (cropPageEnumList[cropPageEnumIndex] == CropPageEnum.CropAllPagesWM) { cropPageListInterval -= pdfviewer.Document.PageCount; } else { cropPageListInterval--; }
                
                if (cropPageList.Count - cropPageListInterval == 0) { pdfviewer.SetCropMode(false); } else { pdfviewer.SetCropMode(true, cropPageList.GetRange(0, cropPageList.Count - cropPageListInterval)); }
                return true;
            }
            else
            {
                return false;
            }
        }

        public bool Undo()
        {
            if (cropPageEnumIndex > -1)
            {
                if (cropPageEnumList[cropPageEnumIndex] == CropPageEnum.CropAllPagesWM)
                {
                    cropPageListInterval += pdfviewer.Document.PageCount;
                }
                else
                {
                    cropPageListInterval++;
                }
                if (cropPageList.Count - cropPageListInterval == 0) { pdfviewer.SetCropMode(false); } else { pdfviewer.SetCropMode(true, cropPageList.GetRange(0, cropPageList.Count - cropPageListInterval)); }

                cropPageEnumIndex--;
                return true;
            }
            else
            {
                return false;
            }


        }
    }
}