#include "RawMap.h"

#include "../clib/logfacility.h"
#include "../clib/passert.h"

#include "uopreader/uop.h"
#include "uopreader/uophash.h"

#include <cstdio>
#include <cstring>
#include <map>

namespace Pol
{
namespace Plib
{
USTRUCT_MAPINFO RawMap::get_cell( unsigned int blockidx, unsigned int x_offset,
                                  unsigned int y_offset )
{
  return m_mapinfo_vec.at( blockidx ).cell[y_offset][x_offset];
}

signed char RawMap::rawinfo( unsigned short x, unsigned short y, USTRUCT_MAPINFO* gi )
{
  passert_r( is_init, "Tried to read map information before loading the map files" );
  passert( m_mapwidth > 0 && m_mapheight > 0 && x < m_mapwidth && y < m_mapheight );

  unsigned int x_block = x / 8;
  unsigned int y_block = y / 8;
  unsigned int block = ( x_block * ( m_mapheight / 8 ) + y_block );

  unsigned int x_offset = x & 0x7;
  unsigned int y_offset = y & 0x7;

  *gi = get_cell( block, x_offset, y_offset );
  return gi->z;
}

void RawMap::add_block( const USTRUCT_MAPINFO_BLOCK& block )
{
  m_mapinfo_vec.push_back( block );
}

void RawMap::set_bounds( unsigned short width, unsigned short height )
{
  m_mapwidth = width;
  m_mapheight = height;
}

unsigned int RawMap::load_map_difflist( FILE* mapdifl_file )
{
  unsigned index = 0;
  if ( mapdifl_file != nullptr )
  {
    u32 blockid;
    while ( fread( &blockid, sizeof blockid, 1, mapdifl_file ) == 1 )
    {
      mapdifl[blockid] = index;
      ++index;
    }
  }
  return index;
}

unsigned int RawMap::load_full_map( FILE* mapfile, FILE* mapdif_file )
{
  passert_r( !is_init, "tried to initialize RawMap twice" );

  if ( mapfile == nullptr )
    throw std::runtime_error( "load_full_map: mapfile is not open" );

  if ( mapdifl.size() > 0 && mapdif_file == nullptr )
    throw std::runtime_error( "load_full_map: mapdifl is loaded but mapdif is not" );

  unsigned int block = 0;
  USTRUCT_MAPINFO_BLOCK buffer;

  while ( fread( &buffer, sizeof buffer, 1, mapfile ) == 1 )
  {
    auto citr = mapdifl.find( block );
    if ( citr == mapdifl.end() )
    {
      add_block( buffer );
    }
    else
    {
      // it's in the dif file.. get it from there.
      unsigned dif_index = ( *citr ).second;
      unsigned int file_offset = dif_index * sizeof( USTRUCT_MAPINFO_BLOCK );
      if ( fseek( mapdif_file, file_offset, SEEK_SET ) != 0 )
        throw std::runtime_error( "rawmapinfo: fseek(mapdif_file) failure" );

      if ( fread( &buffer, sizeof buffer, 1, mapdif_file ) != 1 )
        throw std::runtime_error( "rawmapinfo: fread(mapdif_file) failure" );
      add_block( buffer );
    }
    ++block;
  }

  is_init = true;
  return block;
}

// TODO: cleanup the code
unsigned int RawMap::load_full_map( int uo_mapid, std::istream& ifs )
{
  auto maphash = []( int mapid, size_t chunkidx )
  {
    char mapstring[1024];
    snprintf( mapstring, sizeof mapstring, "build/map%dlegacymul/%08i.dat", mapid, (int)chunkidx );
    return HashLittle2( mapstring );
  };

  passert_r( !is_init, "tried to initialize RawMap twice" );

  if ( !ifs )
  {
    ERROR_PRINTLN( "Error when opening UOP file." );
    return 0;
  }

  kaitai::kstream ks( &ifs );
  uop_t uopfile( &ks );

  size_t totalSize = 0;
  std::map<uint64_t, uop_t::file_t*> filemap;

  // First pass over the data to build up filehash -> file mapping and calculate total map size.
  uop_t::block_addr_t* currentblock = uopfile.header()->firstblock();
  do
  {
    for ( auto file : *currentblock->block_body()->files() )
    {
      if ( file == nullptr )
        continue;
      if ( file->decompressed_size() == 0 )
        continue;

      passert_r( file->compression_type() == uop_t::COMPRESSION_TYPE_NO_COMPRESSION,
                 "This map is zlib compressed and we can't handle that yet." );

      filemap[file->filehash()] = file;
      totalSize += file->decompressed_size();
    }
    currentblock = currentblock->block_body()->next_addr();
  } while ( currentblock != nullptr && filemap.size() < uopfile.header()->nfiles() );

  if ( uopfile.header()->nfiles() != filemap.size() )
    INFO_PRINTLN( "Warning: not all chunks read ({}/{})", filemap.size(),
                  uopfile.header()->nfiles() );

  // Sanity checking and pre-allocate mapinfo vector
  passert_r(
      size_t( totalSize / sizeof( USTRUCT_MAPINFO_BLOCK ) ) * sizeof( USTRUCT_MAPINFO_BLOCK ) ==
          totalSize,
      "Not an integer number of blocks! Check if the sizes are correct." );
  m_mapinfo_vec.clear();
  m_mapinfo_vec.resize( totalSize / sizeof( USTRUCT_MAPINFO_BLOCK ) );

  // Reads the mapinfo by concatenating all tiles, in the correct order, directly into the mapinfo
  // vector.
  size_t vecidx = 0;
  for ( size_t i = 0, remaining = totalSize; i < filemap.size(); i++ )
  {
    auto fileitr = filemap.find( maphash( uo_mapid, i ) );
    if ( fileitr == filemap.end() )
    {
      ERROR_PRINTLN( "Couldn't find file hash: {}", std::to_string( maphash( uo_mapid, i ) ) );
      throw std::runtime_error( "UOP map is missing a file chunk." );
    }

    auto file = fileitr->second;

    passert( remaining >= file->data()->filebytes().size() );
    memcpy( &m_mapinfo_vec[vecidx], file->data()->filebytes().data(),
            file->data()->filebytes().size() );

    remaining -= file->data()->filebytes().size();
    vecidx += file->data()->filebytes().size() / sizeof( USTRUCT_MAPINFO_BLOCK );
  }

  if ( !m_mapinfo_vec.empty() )
    is_init = true;

  return (unsigned int)m_mapinfo_vec.size();
}

RawMap::RawMap() : is_init( false ), m_mapinfo_vec(), mapdifl(), m_mapwidth( 0 ), m_mapheight( 0 )
{
}

}  // namespace Plib
}  // namespace Pol