// Copyright (C) 2010, Guy Barrand. All rights reserved.
// See the file tools.license for terms.

#ifndef tools_png
#define tools_png

#include <cstdio> //FILE,size_t

#include <string>

#include <tools/sout>
#include <tools/mnmx>

#ifdef TOOLS_USE_NATIVE_PNG
#include <png.h>
#else
#include <ourex_png.h> //enforce ourex png
#endif

namespace tools {
namespace png {

inline bool is(const std::string& a_file){
  FILE* file = ::fopen(a_file.c_str(),"rb");
  if(!file) return false; //if file does not exist, then it is not a png !
  png_byte header[8];	// 8 is the maximum size that can be checked
  size_t nitem = ::fread(header,1,8,file);
  ::fclose(file);
  if(nitem!=8) return false;
  return ::png_sig_cmp(header,0,8)?false:true;
}

}}

#include <ostream>

namespace tools {
namespace png {

inline unsigned char* read_FILE(FILE* a_file,unsigned int& a_width,unsigned int& a_height,unsigned int& a_bpp) {

  png_byte header[8];	// 8 is the maximum size that can be checked
  if(::fread(header,1,8,a_file)!=8) {
    a_width = 0;
    a_height = 0;
    a_bpp = 0;
    return 0;
  }
  if(::png_sig_cmp(header,0,8)) {
    a_width = 0;
    a_height = 0;
    a_bpp = 0;
    return 0;
  }

  png_structp png_ptr =
    ::png_create_read_struct(PNG_LIBPNG_VER_STRING,NULL,NULL,NULL);
  if(!png_ptr) {
    a_width = 0;
    a_height = 0;
    a_bpp = 0;
    return 0;
  }

  png_infop info_ptr = ::png_create_info_struct(png_ptr);
  if(!info_ptr) {
    ::png_destroy_read_struct(&png_ptr,NULL,NULL);
    a_width = 0;
    a_height = 0;
    a_bpp = 0;
    return 0;
  }

  if(::setjmp(png_jmpbuf(png_ptr))) {
    ::png_destroy_read_struct(&png_ptr,&info_ptr,NULL);
    a_width = 0;
    a_height = 0;
    a_bpp = 0;
    return 0;
  }

  ::png_init_io(png_ptr,a_file);
  ::png_set_sig_bytes(png_ptr,8);

  ::png_read_info(png_ptr,info_ptr);

  int width = info_ptr->width;
  int height = info_ptr->height;
  int bpp = info_ptr->width?info_ptr->rowbytes/info_ptr->width:0;

  if((width<=0)||(height<=0)||(bpp<=0)) {
    ::png_destroy_read_struct(&png_ptr,&info_ptr,NULL);
    a_width = 0;
    a_height = 0;
    a_bpp = 0;
    return 0;
  }

  a_bpp = bpp; //avoid the clobbered -W warning.

  //png_byte color_type = info_ptr->color_type;
  //info_ptr->bit_depth;

  //int number_of_passes = ::png_set_interlace_handling(png_ptr);
  ::png_read_update_info(png_ptr,info_ptr);

  if(::setjmp(png_jmpbuf(png_ptr))) {
    ::png_destroy_read_struct(&png_ptr,&info_ptr,NULL);
    a_width = 0;
    a_height = 0;
    a_bpp = 0;
    return 0;
  }

  unsigned char* buffer = new unsigned char[info_ptr->rowbytes * height];
  if(!buffer) {
    ::png_destroy_read_struct(&png_ptr,&info_ptr,NULL);
    a_height = 0;
    a_width = 0;
    a_bpp = 0;
    return 0;
  }

 {png_bytep* row_pointers = new png_bytep[height];
  png_byte* pos = buffer+info_ptr->rowbytes*(height-1);
  for(int y=0;y<height;y++) {
    row_pointers[y] = pos;
    pos -= info_ptr->rowbytes;
  }
  ::png_read_image(png_ptr,row_pointers);
  delete [] row_pointers;}

  ::png_read_end(png_ptr,info_ptr);

  ::png_destroy_read_struct(&png_ptr,&info_ptr,NULL);

  a_width = width;
  a_height = height;
  //a_bpp = bpp; //avoid the clobbered -W warning.

  return buffer;
}

inline unsigned char* read(std::ostream& a_out,const std::string& a_file,unsigned int& a_width,unsigned int& a_height,unsigned int& a_bpp) {
  //a_bpp = number of bytes per pixel.
  FILE* file = fopen(a_file.c_str(),"rb");
  if(!file) {
    a_out << "tools::png::read :"
          << " can't open file " << tools::sout(a_file) << "."
          << std::endl;
    a_width = 0;
    a_height = 0;
    a_bpp = 0;
    return 0;
  }
  unsigned char* buffer = read_FILE(file,a_width,a_height,a_bpp);
  if(!buffer) {
    ::fclose(file);
    a_width = 0;
    a_height = 0;
    a_bpp = 0;
    a_out << "tools::png::read :"
          << " read_FILE " << tools::sout(a_file) << " failed."
          << std::endl;
    return 0;
  }
  ::fclose(file);
  return buffer;
}

inline unsigned char* read_part(std::ostream& a_out,
                                const std::string& a_file,
                                unsigned int a_sx,unsigned int a_sy,
                                unsigned int a_sw,unsigned int a_sh,
                                unsigned int& a_rw,unsigned int& a_rh,
                                unsigned int& a_rbpp) {
  a_out << "tools::png::read_part :"
        << " not yet implemented."
        << std::endl;
  a_rw = 0;
  a_rh = 0;
  a_rbpp = 0;
  return 0;

  unsigned int w,h,bpp;
  unsigned char* buffer = read(a_out,a_file,w,h,bpp);
  if(!buffer){
    a_rw = 0;
    a_rh = 0;
    a_rbpp = 0;
    return 0;
  }

  if((a_sx>=w)||(a_sy>=h)){
    delete [] buffer;
    a_rw = 0;
    a_rh = 0;
    a_rbpp = 0;
    return 0;
  }

  // 012345
  a_rw = tools::mn<unsigned int>(w-a_sx,a_sw);
  a_rh = tools::mn<unsigned int>(h-a_sy,a_sh);
  a_rbpp = bpp;

  if(!a_rw||!a_rh||!a_rbpp){
    delete [] buffer;
    a_rw = 0;
    a_rh = 0;
    a_rbpp = 0;
    return 0;
  }

  unsigned char* rb = new unsigned char[a_rw*a_rh*a_rbpp];
  if(!rb) {
    delete [] buffer;
    a_rw = 0;
    a_rh = 0;
    a_rbpp = 0;
    return 0;
  }

  unsigned int rstride = a_rw * a_rbpp;
  unsigned char* rpos = rb;

  unsigned int stride = w * bpp;
  unsigned char* pos = buffer+a_sy*stride+a_sx*bpp;

  for(unsigned int j=0;j<a_rh;j++,rpos+=rstride,pos+=stride) {//j=0 -> bottom.
    ::memcpy(rpos,pos,rstride);
  }

  delete [] buffer;

  return rb;
}

inline bool write_FILE(FILE* a_file,unsigned char* a_buffer,unsigned int a_width,unsigned int a_height,unsigned int a_bpp) {
  //from gl2ps.c.
  if((a_bpp!=3)&&(a_bpp!=4)) {
    return false;
  }

  png_structp png_ptr;
  if(!(png_ptr = ::png_create_write_struct
                    (PNG_LIBPNG_VER_STRING,NULL,NULL,NULL))) return false;

  png_infop info_ptr;
  if(!(info_ptr = ::png_create_info_struct(png_ptr))){
    ::png_destroy_write_struct(&png_ptr,NULL);
    return false;
  }

  if(::setjmp(png_ptr->jmpbuf)) {
    ::png_destroy_write_struct(&png_ptr,&info_ptr);
    return false;
  }

  ::png_init_io(png_ptr,a_file);
  ::png_set_compression_level(png_ptr,Z_DEFAULT_COMPRESSION);
  ::png_set_IHDR(png_ptr,info_ptr,a_width,a_height,8,
                 a_bpp==3?PNG_COLOR_TYPE_RGB:PNG_COLOR_TYPE_RGBA,
                 PNG_INTERLACE_NONE,
                 PNG_COMPRESSION_TYPE_BASE,PNG_FILTER_TYPE_BASE);
  ::png_write_info(png_ptr,info_ptr);

  for(unsigned int row=0;row<a_height;row++){
    unsigned char* pos = a_buffer+(a_height-1-row)*(a_width*a_bpp);
    ::png_write_row(png_ptr,(png_bytep)pos);
  }

  ::png_write_end(png_ptr,info_ptr);
  ::png_destroy_write_struct(&png_ptr,&info_ptr);
  return true;
}

inline bool write(std::ostream& a_out,
                  const std::string& a_file,
                  unsigned char* a_buffer,
                  unsigned int a_width,
                  unsigned int a_height,
                  unsigned int a_bpp) {
  FILE* file = ::fopen(a_file.c_str(),"wb");
  if(!file) {
    a_out << "tools::png::write :"
          << " can't open file " << tools::sout(a_file) << "."
          << std::endl;
    return false;
  }
  if(!write_FILE(file,a_buffer,a_width,a_height,a_bpp)) {
    ::fclose(file);
    a_out << "tools::png::write :"
          << " can't write file " << tools::sout(a_file) << "."
          << std::endl;
    return false;
  }
  ::fclose(file);
  return true;
}

inline bool infos_FILE(FILE* a_file,unsigned int& a_width,unsigned int& a_height,unsigned int& a_bpp) {
  //a_bpp = number of bytes per pixel.
  png_byte header[8];	// 8 is the maximum size that can be checked
  if(::fread(header,1,8,a_file)!=8) {
    a_width = 0;
    a_height = 0;
    a_bpp = 0;
    return false;
  }
  if(::png_sig_cmp(header,0,8)) {
    a_width = 0;
    a_height = 0;
    a_bpp = 0;
    return false;
  }

  png_structp png_ptr =
    ::png_create_read_struct(PNG_LIBPNG_VER_STRING,NULL,NULL,NULL);
  if(!png_ptr) {
    a_width = 0;
    a_height = 0;
    a_bpp = 0;
    return false;
  }

  png_infop info_ptr = ::png_create_info_struct(png_ptr);
  if(!info_ptr) {
    a_width = 0;
    a_height = 0;
    a_bpp = 0;
    return false;
  }

  if(::setjmp(png_jmpbuf(png_ptr))) {
    a_width = 0;
    a_height = 0;
    a_bpp = 0;
    return false;
  }

  ::png_init_io(png_ptr,a_file);
  ::png_set_sig_bytes(png_ptr,8);
  ::png_read_info(png_ptr,info_ptr);

  int width = info_ptr->width;
  int height = info_ptr->height;
  a_bpp = info_ptr->width?info_ptr->rowbytes/info_ptr->width:0;

  ::png_destroy_read_struct(&png_ptr,&info_ptr,NULL);

  a_width = width;
  a_height = height;
  //a_bpp = bpp; //avoid the clobbered -W warning.

  return true;
}

inline bool infos(std::ostream& a_out,const std::string& a_file,unsigned int& a_width,unsigned int& a_height,unsigned int& a_bpp) {
  if(!is(a_file)) {
    a_out << "tools::png::infos :"
          << " file " << a_file << " is not png."
          << std::endl;
    a_width = 0;
    a_height = 0;
    a_bpp = 0;
    return false;
  }

  FILE* file = ::fopen(a_file.c_str(),"rb");
  if(!file) {
    a_out << "tools::png::infos :"
          << " can't open " << a_file
          << std::endl;
    a_width = 0;
    a_height = 0;
    a_bpp = 0;
    return false;
  }

  unsigned int w,h,bpp;
  bool status = infos_FILE(file,w,h,bpp);

  ::fclose(file);

  if(!status) {
    a_out << "tools::png::infos :"
              << " problem reading " << a_file
              << std::endl;
    a_width = 0;
    a_height = 0;
    a_bpp = 0;
    return false;
  }

  a_width = w;
  a_height = h;
  a_bpp = bpp;
  return true;
}

}}

#include <tools/xpm>

namespace tools {
namespace png {

inline bool to_xpm(std::ostream& a_out,const std::string& a_file,const std::string& a_name,bool a_verbose = false) {
  return tools::xpm::to_xpm(a_out,a_file,a_name,read,a_verbose);
}

}}

#include <tools/image>
#include <vector>

namespace tools {
namespace png {

inline bool concatenate(std::ostream& a_out,
                        const std::vector<std::string>& a_files,
                        unsigned int a_cols,unsigned int a_rows,
                        unsigned int a_bw,unsigned int a_bh,
                        unsigned char a_bc,
                        const std::string& a_file) {
  unsigned int wa,ha,bppa;
  unsigned char* ba =
    tools::image::concatenate
      (a_out,a_files,a_cols,a_rows,a_bw,a_bh,a_bc,read,wa,ha,bppa);
  if(!ba) {
    a_out << "tools::png::concatenate :"
          << " failed to concatenate all buffers."
          << std::endl;
    delete [] ba;
    return false;
  }

  FILE* file = ::fopen(a_file.c_str(),"wb");
  if(!file) {
    a_out << "tools::png::concatenate :"
          << " can't open " << file << " for writing."
          << std::endl;
    delete [] ba;
    return false;
  }

  if(!write_FILE(file,ba,wa,ha,bppa)) {
    a_out << "tools::png::concatenate :"
          << " can't write " << a_file << "."
          << std::endl;
    delete [] ba;
    ::fclose(file);
    return false;
  }

  delete [] ba;
  ::fclose(file);
  return true;
}

class reader : public virtual tools::image::ireader {
public:
  virtual tools::image::ireader* copy() const {return new reader(*this);}
  virtual bool is(const std::string& a_file) const {return tools::png::is(a_file);}
  virtual bool infos(std::ostream& a_out,const std::string& a_file,
                     unsigned int& a_width,unsigned int& a_height,unsigned int& a_bpp) const {
    return tools::png::infos(a_out,a_file,a_width,a_height,a_bpp);
  }
  virtual unsigned char* read(std::ostream& a_out,const std::string& a_file,
                              unsigned int& a_width,unsigned int& a_height,unsigned int& a_bpp) const {
    return tools::png::read(a_out,a_file,a_width,a_height,a_bpp);
  }
  virtual unsigned char* read_part(std::ostream& a_out,const std::string& a_file,
                                   unsigned int a_sx,unsigned int a_sy,
                                   unsigned int a_sw,unsigned int a_sh,
                                   unsigned int& a_rw,unsigned int& a_rh,unsigned int& a_rbpp) const {
    return tools::png::read_part(a_out,a_file,a_sx,a_sy,a_sw,a_sh,a_rw,a_rh,a_rbpp);
  }
public:
  reader(){}
  virtual ~reader(){}
public:
  reader(const reader&):ireader(){}
  reader& operator=(const reader&){return *this;}
};

}}

#endif