/*
 * This class is part of the book "iText in Action - 2nd Edition"
 * written by Bruno Lowagie (ISBN: 9781935182610)
 * For more info, go to: http://itextpdf.com/examples/
 * This example only works with the AGPL version of iText.
 */
using System;
using System.IO;
using System.Text;
using Ionic.Zip;
using iTextSharp.text;
using iTextSharp.text.pdf;

namespace kuujinbo.iTextInAction2Ed.Chapter06 {
  public class FormInformation : IWriter {
// ===========================================================================
    public const string RESULT = "form_info.txt";
// --------------------------------------------------------------------------- 
    public void Write(Stream stream) {
      string datasheet = Path.Combine(Utility.ResourcePdf, "datasheet.pdf"); 
      using (ZipFile zip = new ZipFile()) { 
        // Create a reader to extract info
        PdfReader reader = new PdfReader(datasheet);
        // Get the fields from the reader (read-only!!!)
        AcroFields form = reader.AcroFields;
        // Loop over the fields and get info about them 
        StringBuilder sb = new StringBuilder();       
        foreach (string key in form.Fields.Keys) {
          sb.Append(key);
          sb.Append(": ");
          switch (form.GetFieldType(key)) {
            case AcroFields.FIELD_TYPE_CHECKBOX:
              sb.Append("Checkbox");
              break;
            case AcroFields.FIELD_TYPE_COMBO:
              sb.Append("Combobox");
              break;
            case AcroFields.FIELD_TYPE_LIST:
              sb.Append("List");
              break;
            case AcroFields.FIELD_TYPE_NONE:
              sb.Append("None");
              break;
            case AcroFields.FIELD_TYPE_PUSHBUTTON:
              sb.Append("Pushbutton");
              break;
            case AcroFields.FIELD_TYPE_RADIOBUTTON:
              sb.Append("Radiobutton");
              break;
            case AcroFields.FIELD_TYPE_SIGNATURE:
              sb.Append("Signature");
              break;
            case AcroFields.FIELD_TYPE_TEXT:
              sb.Append("Text");
              break;
            default:
              sb.Append("?");
              break;
          }
          sb.Append(Environment.NewLine);
        } 
        
        // Get possible values for field "CP_1"
        sb.Append("Possible values for CP_1:");
        sb.Append(Environment.NewLine);
        string[] states = form.GetAppearanceStates("CP_1");
        for (int i = 0; i < states.Length; i++) {
          sb.Append(" - ");
          sb.Append(states[i]);
          sb.Append(Environment.NewLine);
        }

        // Get possible values for field "category"
        sb.Append("Possible values for category:");
        sb.Append(Environment.NewLine);
        states = form.GetAppearanceStates("category");
        for (int i = 0; i < states.Length - 1; i++) {
          sb.Append(states[i]);
          sb.Append(", ");
        }
        sb.Append(states[states.Length - 1]);
        
        zip.AddEntry(RESULT, sb.ToString());
        zip.AddFile(datasheet, "");
        zip.Save(stream);
      }      
    }
// ===========================================================================
  }
}