using System;
using PdfSharp.Pdf;
using PdfSharp.Pdf.IO;
using LCU.Library.Internal.FileOperationsModels.Models;
namespace LCU.Api.Internal.FileOperations.Validations;

public static class PdfValidations
{
    private const string PdfPageDoesntExist = "PDF Page Doesn't Exist.";
    private const string PdfPageCantBeLessThanOne = "PDF Page Can't Be Less Than 1.";

    public static RequestResponse ValidatePdfPageExists(RequestResponse requestResponse, string pdfName, int pageNumber)
    {
        try
        {
            PdfDocument inputDocument = PdfReader.Open(pdfName, PdfDocumentOpenMode.Import);

            if(pageNumber <= 0)
            {
                requestResponse.IsSuccessful = false;
                requestResponse.MessageStack.Add(PdfPageCantBeLessThanOne);
            }

            if (pageNumber > inputDocument.PageCount)
            {
                requestResponse.IsSuccessful = false;
                requestResponse.MessageStack.Add(PdfPageDoesntExist);
            }
        }
        catch (Exception exception)
        {
            requestResponse.IsSuccessful = false;
            requestResponse.MessageStack.Add(exception.Message);
        }

        return requestResponse;
    }
}