//---------------------------------------------------------------------------------------
// Copyright (c) 2001-2020 by PDFTron Systems Inc. All Rights Reserved.
// Consult legal.txt regarding legal and license information.
//---------------------------------------------------------------------------------------

#include <PDF/PDFNet.h>
#include <PDF/PDFDoc.h>
#include <PDF/ElementReader.h>
#include <PDF/ElementBuilder.h>
#include <PDF/Element.h>
#include <PDF/Annots/Square.h>
#include <Common/Matrix2D.h>
#include <iostream>

using namespace pdftron;
using namespace std;
using namespace PDF;
using namespace Common;

void ProcessElements(PDFDoc& doc, Page& page, ElementReader& reader) 
{
	for (Element element=reader.Next(); element; element = reader.Next()) 	// Read page contents
	{
		switch (element.GetType())
		{			
			case Element::e_text: 				// Process text strings...
			{
				CharIterator itr = element.GetCharIterator();
				GState gs = element.GetGState();
				Font font = gs.GetFont();
				double font_size = gs.GetFontSize();
				double horiz_spacing = gs.GetHorizontalScale() / 100.0;
				Matrix2D text_mtx = element.GetTextMatrix();
				Matrix2D pos(1, 0, 0, 1, 0, 0);
				Matrix2D font_mtx(font_size * horiz_spacing, 0, 0, font_size, 0, 0);

				double units_per_em = font.GetUnitsPerEm();
				font_mtx *= Matrix2D(1.0 / units_per_em, 0, 0, -1.0 / units_per_em, 0, 0);

				ElementBuilder bldr;

				for (; itr.HasNext(); itr.Next())
				{
					pos.m_h = itr.Current().x;
					pos.m_v = itr.Current().y;
					Matrix2D path_mtx(text_mtx);
					path_mtx *= pos;
					path_mtx *= font_mtx;

					PathData pathData = font.GetGlyphPath(itr.Current().char_code, false, &path_mtx);
					Element tempElement = bldr.CreatePath(pathData.GetPoints(), pathData.GetOperators());
					Rect bbox;
					tempElement.GetBBox(bbox);
					///////////////////////////////////////////////////////////////////
					// Add an annotation to show that the bounding box is as expected
					// just for debug purposes
					Annots::Square sqr = Annots::Square::Create(doc, bbox);
					sqr.SetColor(ColorPt(1, 0, 1), 3);
					sqr.SetBorderStyle(BorderStyle(BorderStyle::e_solid, 0.25));
					sqr.RefreshAppearance();
					page.AnnotPushBack(sqr);
					///////////////////////////////////////////////////////////////////
				}
			}
			break;
			
			case Element::e_form:				// Process form XObjects
			{
					reader.FormBegin(); 
					ProcessElements(doc, page, reader);
					reader.End(); 
			}
			break; 
		}
	}
}


int main(int argc, char *argv[])
{
	int ret = 0;
	PDFNet::Initialize();

	string input_path = "../../TestFiles/";
	string output_path = "../../TestFiles/Output/";
	string input_filename = "newsletter.pdf";
	string output_filename = "newsletter_bboxes.pdf";

	try	// Extract text data from all pages in the document
	{
		PDFDoc doc((input_path + "newsletter.pdf").c_str());
		doc.InitSecurityHandler();

		int pgnum = doc.GetPageCount();
		
		PageIterator itr;
		ElementReader page_reader;

		for (itr = doc.GetPageIterator(); itr.HasNext(); itr.Next())		//  Read every page
		{				
			page_reader.Begin(itr.Current());
			ProcessElements(doc, itr.Current(), page_reader);
			page_reader.End();
		}
		doc.Save(output_path + output_filename, SDF::SDFDoc::e_linearized, 0);
		cout << "Done." << endl;
	}
	catch(std::exception& e)
	{
		cout << e.what() << endl;
		ret = 1;
	}
	catch(...)
	{
		cout << "Unknown Exception" << endl;
		ret = 1;
	}

	PDFNet::Terminate();
	return ret;
}