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

#ifndef tools_image
#define tools_image

#include <vector>
#include <cstring> //memcpy
#include <cstdio> //fopen

#include "forit"

namespace tools {
namespace image {

// give a set of cols*rows same size rgb-image and build 
// a big image :
inline unsigned char* concatenate(unsigned char** a_buffers,
                                  unsigned int a_w,unsigned int a_h,
                                  unsigned int a_bpp,
                                  unsigned int a_cols,unsigned int a_rows,
                                  unsigned int a_bw,unsigned int a_bh,
                                  unsigned char a_bc,
                                  unsigned int& a_rw,unsigned int& a_rh){

  // assume a_buffers has a_cols*a_rows entries.
  // a_buffers[0] is bottom-left
  // a_row=0 is bottom.

  unsigned int wbw = a_w + 2*a_bw;
  unsigned int hbh = a_h + 2*a_bh;

  a_rw = wbw * a_cols;
  a_rh = hbh * a_rows;

  //printf("debug : %d %d\n",a_rw,a_rh);

  // on big concatenated image the below may fail :
  unsigned char* rb = new unsigned char[a_rh*a_rw*a_bpp];
  if(!rb) {a_rw = 0;a_rh = 0;return 0;}

  unsigned int wbw3 = wbw*a_bpp;
  unsigned int aw3 = a_w*a_bpp;
  
  //copy tiles :  
  unsigned int index = 0;
  for(unsigned int j=0;j<a_rows;j++) {
    for(unsigned int i=0;i<a_cols;i++) {
      unsigned char* tile = a_buffers[index];

      for(unsigned int r=0;r<hbh;r++) {
        unsigned char* pos = rb + (j*hbh+r)*a_rw*a_bpp + i*wbw*a_bpp;
        ::memset(pos,a_bc,wbw3);
      }

      for(unsigned int r=0;r<a_h;r++) {
        unsigned char* pos = rb + (j*hbh+r+a_bh)*a_rw*a_bpp + (i*wbw+a_bw)*a_bpp;
        unsigned char* ptile = tile+r*aw3;        
        for(unsigned int c=0;c<aw3;c++,pos++,ptile++) *pos = *ptile;
      }

      index++;
    }
  }

  return rb;
}

}}

#include <ostream>
#include <string>

namespace tools {
namespace image {

typedef unsigned char* (*file_reader)(std::ostream&,const std::string&,unsigned int&,unsigned int&,unsigned int&);

inline unsigned char* 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,
                                  file_reader a_file_reader,
                                  unsigned int& a_w,unsigned int& a_h,
                                  unsigned int& a_bpp) {
  // a_files[0] is cols=0, rows=0
  // a_files[1] is cols=1, rows=0
  // a_files[2] is cols=2, rows=0
  // ...
  // and row=0 is bottom of big image.

  unsigned int number = a_cols*a_rows;
  if(number!=a_files.size()) {
    a_out << "tools::image::concatenate :"
              << " bad number of files. " << number << " expected."
              << std::endl;
    a_bpp = a_w = a_h = 0;
    return 0;
  }
  if(a_files.empty()) {
    a_out << "tools::image::concatenate :"
          << " list of files is empty."
          << std::endl;
    a_bpp = a_w = a_h = 0;
    return 0;
  }

  unsigned int w1 = 0;
  unsigned int h1 = 0;
  unsigned int bpp1 = 0;
   
  typedef unsigned char* buffer_t;
  buffer_t* bs = new buffer_t[number];
 {for(unsigned int i=0;i<number;i++) {bs[i] = 0;}}

  bool read_failed = false;
  unsigned int index = 0;
  for(unsigned int j=0;j<a_rows;j++) {
    for(unsigned int i=0;i<a_cols;i++) {
      const std::string& file = a_files[index];
      unsigned int w,h,bpp;
      unsigned char* b = a_file_reader(a_out,file,w,h,bpp);
      if(!b) {
        a_out << "tools::image::concatenate :"
              << " can't read " << file << " expected."
              << std::endl;
        read_failed = true;
        break;
      }
      if(!index) {
        w1 = w;
        h1 = h;
        bpp1 = bpp;
      } else {
        if(w!=w1) {
          a_out << "tools::image::concatenate :"
                << " file " << file
                << " does not have same width image as the first file one."
                << " (" << w << "," << w1 << ")."
                << std::endl;
          delete [] b;
          read_failed = true;
          break;
        }
        if(h!=h1) {
          a_out << "tools::image::concatenate :"
                << " file " << file
                << " does not have same height image as the first file one."
                << " (" << h << "," << h1 << ")."
                << std::endl;
          delete [] b;
          read_failed = true;
          break;
        }
        if(bpp!=bpp1) {
          a_out << "tools::image::concatenate :"
                << " file " << file
                << " does not have same bytes per pixel as the first file one."
                << " (" << h << "," << h1 << ")."
                << std::endl;
          delete [] b;
          read_failed = true;
          break;
        }
      }

      bs[index] = b;

      index++;
    }
    if(read_failed) break;
  }

  if(read_failed) {
    {for(unsigned int i=0;i<number;i++) {delete [] bs[i];}}
    a_bpp = a_w = a_h = 0;
    return 0;
  }

  unsigned int wa,ha;
  unsigned char* ba = image::concatenate(bs,w1,h1,bpp1,a_cols,a_rows,a_bw,a_bh,a_bc,wa,ha);
  if(!ba) {
    a_out << "tools::image::concatenate :"
          << " failed to concatenate all buffers."
          << std::endl;
    {for(unsigned int i=0;i<number;i++) {delete [] bs[i];}}
    a_bpp = a_w = a_h = 0;
    return 0;
  } 

  {for(unsigned int i=0;i<number;i++) {delete [] bs[i];}}

  a_w = wa;
  a_h = ha;
  a_bpp = bpp1;
  return ba;
}

typedef unsigned char* (*reader)(FILE*,unsigned int&,unsigned int&);
typedef bool(*writer)(FILE*,unsigned char*,unsigned int,unsigned int);

inline bool convert(std::ostream& a_out,
                    const std::string& a_sin,
                    reader a_reader,
                    const std::string& a_sout,
                    writer a_writer){
  
  FILE* fin = ::fopen(a_sin.c_str(),"rb");
  if(!fin) {
    a_out << "tools::image::convert :"
          << " can't open " << a_sin
          << std::endl;
    return false;
  }

  unsigned int w,h;
  unsigned char* b = a_reader(fin,w,h);
  if(!b) {
    a_out << "tools::image::convert :"
          << " can't read " << a_sin
          << std::endl;
    ::fclose(fin);
    return false;
  }
  ::fclose(fin);

  FILE* fout = ::fopen(a_sout.c_str(),"wb");
  if(!fout) {
    a_out << "tools::image::convert :"
          << " can't open " << a_sout
          << std::endl;
    delete [] b;
    return false;
  }

  if(!a_writer(fout,b,w,h)) {
    a_out << "tools::image::convert :"
          << " can't write " << a_sout
          << std::endl;
    ::fclose(fout);
    delete [] b;
    return false;
  }
  ::fclose(fout);
  delete [] b;
  return true;
}

}}

#include "image_reader"

#include "sout"

#include "S_STRING"
#ifdef TOOLS_MEM
#include "mem"
#endif

namespace tools {
namespace image {

class iterator {
public:
  TOOLS_SCLASS(tools::image::iterator)
public:
  virtual ~iterator(){}
public:
  virtual unsigned int entries() const = 0;
  virtual bool next() = 0;
  virtual bool rewind() = 0;
public:
  virtual unsigned int index() const = 0;
  virtual unsigned char* read_image(unsigned int& a_w,unsigned int& a_h,
                                    unsigned int& a_bpp) = 0;
};

class iterator_reader : public virtual iterator {
public:
  TOOLS_SCLASS(tools::image::iterator_reader)
public:
  //still virtual :
  //virtual unsigned int entries() const = 0;
  //virtual bool next() = 0;
  //virtual bool rewind() = 0;
  //virtual unsigned int index() const = 0;
  virtual unsigned char* read_image(unsigned int& a_w,unsigned int& a_h,
                                    unsigned int& a_bpp) {

    std::string file;
    if(begin_file(file)) {
      tools_vforcit(image::ireader*,m_readers,it) {
        if((*it)->is(file)) {
          unsigned char* buffer = _open(*(*it),file,a_w,a_h,a_bpp);
          end_file(file);
          return buffer;        
        }
      }
      end_file(file);
    }
    a_w = 0;a_h = 0;a_bpp = 0;
    return 0;
  }
public:
  virtual bool begin_file(std::string&) = 0;
  virtual bool end_file(const std::string&) = 0;
public:
  iterator_reader(std::ostream& a_out,unsigned int a_limit)
  :m_out(a_out)
  ,m_limit(a_limit)
  {
#ifdef TOOLS_MEM
    mem::increment(s_class().c_str());
#endif
  }
  virtual ~iterator_reader(){
    _clean();
#ifdef TOOLS_MEM
    mem::decrement(s_class().c_str());
#endif
  }
public:
  iterator_reader(const iterator_reader& a_from)
  :iterator(a_from)
  ,m_out(a_from.m_out)
  ,m_limit(a_from.m_limit)
  {
#ifdef TOOLS_MEM
    mem::increment(s_class().c_str());
#endif
    _copy(a_from.m_readers);
  }
  iterator_reader& operator=(const iterator_reader& a_from){
    if(&a_from==this) return *this;
    m_limit = a_from.m_limit;
    _copy(a_from.m_readers);
    return *this;
  }
public:
  void add_reader(ireader* a_reader) {
    m_readers.push_back(a_reader); //take ownership.
  }
protected:
  unsigned char* _open(const image::ireader& a_reader,
                       const std::string& a_path,
                       unsigned int& a_w,unsigned int& a_h,
                       unsigned int& a_bpp){
    // permit to put in common code for jpeg and png.

    unsigned char* buffer = 0;

    if(m_limit) {
      if(!a_reader.infos(m_out,a_path,a_w,a_h,a_bpp)) {
        m_out << "tools::image::iterator_reader::_open :"
              << " for file " << sout(a_path)
              << " ireader::infos failed."
              << std::endl;
        a_w = 0;a_h = 0;a_bpp = 0;
        return 0;
      }
      if((a_w*a_h*a_bpp)>m_limit) {

        //unsigned int sw;
        //unsigned int sh;
        //float aspect = float(w)/float(h);
        //if(aspect>=1) {
        //  sh = 2;
        //  sw = aspect*sh;
        //} else {
        //  sw = 2;
        //  sh = sw/aspect;
        //}
    
        unsigned int sw = 2;
        unsigned int sh = 2;
        while(true) {
          if(((2*sw)*(2*sh)*a_bpp)>m_limit) break;
          sw *=2;
          sh *=2;
        }
    
        unsigned int sx = (a_w-sw)/2;
        unsigned int sy = (a_h-sh)/2;
    
        buffer = a_reader.read_part
                   (m_out,a_path,sx,sy,sw,sh,a_w,a_h,a_bpp);
      } else {
        buffer = a_reader.read(m_out,a_path,a_w,a_h,a_bpp);
      }
    } else {
      buffer = a_reader.read(m_out,a_path,a_w,a_h,a_bpp);
    }
  
    if(!buffer) {
      m_out << "tools::image::iterator_reader::_open :"
            << " for file " << sout(a_path)
            << " read failed."
            << std::endl;
      a_w = 0;a_h = 0;a_bpp = 0;
      return 0;
    }
    
    return buffer;
  }

  void _clean() {
    std::vector<ireader*>::iterator it;
    for(it=m_readers.begin();it!=m_readers.end();) {
      ireader* obj = *it;
      it = m_readers.erase(it);
      delete obj;
    }
  }
  void _copy(const std::vector<ireader*>& a_from) {
    _clean();
    tools_vforcit(ireader*,a_from,it) m_readers.push_back((*it)->copy());
  }
protected:
  std::ostream& m_out; 
  unsigned int m_limit;
  std::vector<ireader*> m_readers;
};

}}

#endif