/*  Zutils - Utilities dealing with compressed files
    Copyright (C) 2009, 2010, 2011, 2012, 2013 Antonio Diaz Diaz.

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#define _FILE_OFFSET_BITS 64

#include <cerrno>
#include <climits>
#include <csignal>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <list>
#include <string>
#include <vector>
#include <dirent.h>
#include <fcntl.h>
#include <stdint.h>
#include <unistd.h>
#include <sys/stat.h>
#if defined(__MSVCRT__) || defined(__OS2__)
#include <io.h>
#endif

#include "arg_parser.h"
#include "zutils.h"
#include "rc.h"

#if CHAR_BIT != 8
#error "Environments where CHAR_BIT != 8 are not supported."
#endif


namespace {

#ifdef O_BINARY
const int o_binary = O_BINARY;
#else
const int o_binary = 0;
#endif

enum Mode { m_none, m_zcat, m_zgrep, m_ztest };


void show_help()
  {
  std::printf( "Zutils is a collection of utilities able to deal with any combination of\n"
               "compressed and uncompressed files transparently. If any given file,\n"
               "including standard input, is compressed, its decompressed content is used.\n"
               "\nThe supported formats are bzip2, gzip, lzip and xz.\n"
               "\nUsage: %s <operation> [options] [files]\n", invocation_name );
  std::printf( "\nTry '%s <operation> --help' for more specific help.\n", invocation_name );
  std::printf( "\nOperations:\n"
               "  -h, --help                 display this help and exit\n"
               "  -V, --version              output version information and exit\n"
               "      --zcat                 zcat operation\n"
               "      --zgrep                zgrep operation\n"
               "      --ztest                ztest operation\n" );
  show_help_addr();
  }


int simple_extension_index( const std::string & name )
  {
  for( int i = 0; i < num_formats; ++i )
    {
    const std::string ext( simple_extensions[i] );
    if( name.size() > ext.size() &&
        name.compare( name.size() - ext.size(), ext.size(), ext ) == 0 )
      return i;
    }
  return -1;
  }


int open_instream( std::string & input_filename, const Mode program_mode,
                   const bool search )
  {
  int infd = open( input_filename.c_str(), O_RDONLY | o_binary );
  if( infd < 0 )
    {
    if( search && ( program_mode == m_zcat || program_mode == m_zgrep ) &&
        simple_extension_index( input_filename ) < 0 )
      {
      for( int i = 0; i < num_formats; ++i )
        {
        const std::string name( input_filename +
                                simple_extensions[format_order[i]] );
        infd = open( name.c_str(), O_RDONLY | o_binary );
        if( infd >= 0 ) { input_filename = name; break; }
        }
      }
    if( infd < 0 )
      show_error2( "Can't open input file", input_filename.c_str() );
    }
  return infd;
  }

#include "zcat.cc"
#include "zgrep.cc"
#include "ztest.cc"

} // end namespace


int main( const int argc, const char * const argv[] )
  {
  enum { format_opt = 256, help_opt, verbose_opt,
         bz2_opt, gz_opt, lz_opt, xz_opt,
         zcat_opt, zgrep_opt, ztest_opt };
  const Arg_parser::Option * options = 0;
  int infd = -1;
  int format_index = -1;
  Mode program_mode = m_none;
  bool recursive = false;
  std::string input_filename;
  std::list< std::string > filenames;
  Cat_options cat_options;
  std::vector< const char * > grep_args;	// args to grep, maybe empty
  std::vector< const char * > ztest_args;	// args to ztest, maybe empty
  invocation_name = argv[0];

  const Arg_parser::Option m_zcat_options[] =
    {
    { 'A', "show-all",         Arg_parser::no  },	// cat
    { 'b', "number-nonblank",  Arg_parser::no  },	// cat
    { 'c', "stdout",           Arg_parser::no  },	// gzip
    { 'd', "decompress",       Arg_parser::no  },	// gzip
    { 'e',  0,                 Arg_parser::no  },	// cat
    { 'E', "show-ends",        Arg_parser::no  },	// cat
    { 'f', "force",            Arg_parser::no  },	// gzip
    { 'h', "help",             Arg_parser::no  },
    { 'l', "list",             Arg_parser::no  },	// gzip
    { 'L', "license",          Arg_parser::no  },	// gzip
    { 'n', "number",           Arg_parser::no  },	// cat
    { 'N', "no-rcfile",        Arg_parser::no  },
    { 'q', "quiet",            Arg_parser::no  },
    { 'r', "recursive",        Arg_parser::no  },
    { 's', "squeeze-blank",    Arg_parser::no  },	// cat
    { 't',  0,                 Arg_parser::no  },	// cat
    { 'T', "show-tabs",        Arg_parser::no  },	// cat
    { 'v', "show-nonprinting", Arg_parser::no  },	// cat
    { 'V', "version",          Arg_parser::no  },
    { format_opt,  "format",   Arg_parser::yes },
    { verbose_opt, "verbose",  Arg_parser::no  },
    { bz2_opt,     "bz2",      Arg_parser::yes },
    { gz_opt,      "gz",       Arg_parser::yes },
    { lz_opt,      "lz",       Arg_parser::yes },
    { xz_opt,      "xz",       Arg_parser::yes },
    { zcat_opt,    "zcat",     Arg_parser::no  },
    {  0 ,  0,                 Arg_parser::no  } };

  const Arg_parser::Option m_zgrep_options[] =
    {
    { 'a', "text",                Arg_parser::no  },	// grep GNU
    { 'A', "after-context",       Arg_parser::yes },	// grep GNU
    { 'b', "byte-offset",         Arg_parser::no  },	// grep GNU
    { 'B', "before-context",      Arg_parser::yes },	// grep GNU
    { 'c', "count",               Arg_parser::no  },	// grep
    { 'C', "context",             Arg_parser::yes },	// grep GNU
    { 'e', "regexp",              Arg_parser::yes },	// grep
    { 'E', "extended-regexp",     Arg_parser::no  },	// grep
    { 'f', "file ",               Arg_parser::yes },	// grep
    { 'F', "fixed-strings",       Arg_parser::no  },	// grep
    { 'h', "no-filename",         Arg_parser::no  },	// grep GNU
    { 'H', "with-filename",       Arg_parser::no  },	// grep GNU
    { 'i', "ignore-case",         Arg_parser::no  },	// grep
    { 'I',  0,                    Arg_parser::no  },	// grep GNU
    { 'l', "files-with-matches",  Arg_parser::no  },	// grep
    { 'L', "files-without-match", Arg_parser::no  },	// grep GNU
    { 'm', "max-count",           Arg_parser::yes },	// grep GNU
    { 'n', "line-number",         Arg_parser::no  },	// grep
    { 'N', "no-rcfile",           Arg_parser::no  },
    { 'o', "only-matching",       Arg_parser::no  },	// grep
    { 'q', "quiet",               Arg_parser::no  },
    { 'r', "recursive",           Arg_parser::no  },
    { 's', "no-messages",         Arg_parser::no  },	// grep
    { 'v', "invert-match",        Arg_parser::no  },	// grep
    { 'V', "version",             Arg_parser::no  },
    { 'w', "word-regexp",         Arg_parser::no  },	// grep GNU
    { 'x', "line-regexp",         Arg_parser::no  },	// grep
    { format_opt,  "format",      Arg_parser::yes },
    { help_opt,    "help",        Arg_parser::no  },
    { verbose_opt, "verbose",     Arg_parser::no  },
    { bz2_opt,     "bz2",         Arg_parser::yes },
    { gz_opt,      "gz",          Arg_parser::yes },
    { lz_opt,      "lz",          Arg_parser::yes },
    { xz_opt,      "xz",          Arg_parser::yes },
    { zgrep_opt,   "zgrep",       Arg_parser::no  },
    {  0 ,  0,                    Arg_parser::no  } };

  const Arg_parser::Option m_ztest_options[] =
    {
    { 'h', "help",          Arg_parser::no  },
    { 'N', "no-rcfile",     Arg_parser::no  },
    { 'q', "quiet",         Arg_parser::no  },
    { 'r', "recursive",     Arg_parser::no  },
    { 'v', "verbose",       Arg_parser::no  },
    { 'V', "version",       Arg_parser::no  },
    { format_opt, "format", Arg_parser::yes },
    { bz2_opt,    "bz2",    Arg_parser::yes },
    { gz_opt,     "gz",     Arg_parser::yes },
    { lz_opt,     "lz",     Arg_parser::yes },
    { xz_opt,     "xz",     Arg_parser::yes },
    { ztest_opt,  "ztest",  Arg_parser::no  },
    {  0 ,  0,              Arg_parser::no  } };

  { // parse operation
  const Arg_parser::Option operations[] =
    {
    { 'h', "help",              Arg_parser::no  },
    { 'V', "version",           Arg_parser::no  },
    { zcat_opt,  "zcat",        Arg_parser::no  },
    { zgrep_opt, "zgrep",       Arg_parser::no  },
    { ztest_opt, "ztest",       Arg_parser::no  },
    {  0 ,  0,                  Arg_parser::no  } };

  const Arg_parser parser( argv[1], ( argc > 2 ) ? argv[2] : 0, operations );
  if( parser.error().size() )				// bad operation
    { show_error( parser.error().c_str(), 0, true ); return 1; }

  if( parser.arguments() > 0 )
    {
    switch( parser.code( 0 ) )
      {
      case  0 : break;
      case 'h': show_help(); return 0;
      case 'V': show_version(); return 0;
      case zcat_opt  : program_mode = m_zcat; options = m_zcat_options;
                       util_name = "zcat"; break;
      case zgrep_opt : program_mode = m_zgrep; options = m_zgrep_options;
                       util_name = "zgrep"; break;
      case ztest_opt : program_mode = m_ztest; options = m_ztest_options;
                       util_name = "ztest"; break;
      default : internal_error( "uncaught option" );
      }
    }

#if defined(__MSVCRT__) || defined(__OS2__)
  setmode( STDIN_FILENO, O_BINARY );
  setmode( STDOUT_FILENO, O_BINARY );
#endif

  if( program_mode == m_none )
    {
    show_error( "You must specify the operation to be performed.", 0, true );
    return 1;
    }
  } // end parse operation

  const int eretval = ( program_mode == m_zgrep ) ? 2 : 1;
  const Arg_parser parser( argc, argv, options );
  if( parser.error().size() )				// bad option
    { show_error( parser.error().c_str(), 0, true ); return eretval; }

  maybe_process_config_file( parser );

  int argind = 0;
  int grep_show_name = -1;
  int grep_list_mode = 0;	// 1 = list matches, -1 = list non matches
  bool grep_pattern_found = false;
  for( ; argind < parser.arguments(); ++argind )
    {
    const int code = parser.code( argind );
    const char * const arg = parser.argument( argind ).c_str();
    if( !code )
      {
      if( program_mode == m_zgrep && !grep_pattern_found )
        { grep_args.push_back( arg ); grep_pattern_found = true; continue; }
      else break;					// no more options
      }
    switch( code )					// common options
      {
      case 'N': continue;
      case format_opt: format_index = parse_format_type( arg ); continue;
      case bz2_opt: parse_compressor( arg, fmt_bz2, eretval ); continue;
      case gz_opt: parse_compressor( arg, fmt_gz, eretval ); continue;
      case lz_opt: parse_compressor( arg, fmt_lz, eretval ); continue;
      case xz_opt: parse_compressor( arg, fmt_xz, eretval ); continue;
      }
    switch( program_mode )
      {
      case m_none: internal_error( "invalid operation" ); break;
      case m_zcat:
        switch( code )
          {
          case 'A': cat_options.show_ends = true;
                    cat_options.show_nonprinting = true;
                    cat_options.show_tabs = true; break;
          case 'b': cat_options.number_lines = 1; break;
          case 'c': break;
          case 'd': break;
          case 'e': cat_options.show_nonprinting = true;  // fall through
          case 'E': cat_options.show_ends = true; break;
          case 'f': break;
          case 'h': show_zcat_help(); return 0;
          case 'l': break;
          case 'L': break;
          case 'n': if( cat_options.number_lines == 0 )
                      { cat_options.number_lines = 2; } break;
          case 'q': verbosity = -1; break;
          case 'r': recursive = true; break;
          case 's': cat_options.squeeze_blank = true; break;
          case 't': cat_options.show_nonprinting = true;  // fall through
          case 'T': cat_options.show_tabs = true; break;
          case 'v': cat_options.show_nonprinting = true; break;
          case 'V': show_version( "Zcat" ); return 0;
          case verbose_opt : if( verbosity < 4 ) ++verbosity; break;
          case zcat_opt : break;
          default : internal_error( "uncaught option" );
          } break;
      case m_zgrep:
        switch( code )
          {
          case 'a': grep_args.push_back( "-a" ); break;
          case 'A': grep_args.push_back( "-A" ); grep_args.push_back( arg ); break;
          case 'b': grep_args.push_back( "-b" ); break;
          case 'B': grep_args.push_back( "-B" ); grep_args.push_back( arg ); break;
          case 'c': grep_args.push_back( "-c" ); break;
          case 'C': grep_args.push_back( "-C" ); grep_args.push_back( arg ); break;
          case 'e': grep_args.push_back( "-e" ); grep_args.push_back( arg );
                    grep_pattern_found = true; break;
          case 'E': grep_args.push_back( "-E" ); break;
          case 'f': grep_args.push_back( "-f" ); grep_args.push_back( arg );
                    grep_pattern_found = true; break;
          case 'F': grep_args.push_back( "-F" ); break;
          case 'h': grep_show_name = false; break;
          case 'H': grep_show_name = true; break;
          case 'i': grep_args.push_back( "-i" ); break;
          case 'I': grep_args.push_back( "-I" ); break;
          case 'l': grep_args.push_back( "-l" ); grep_list_mode = 1; break;
          case 'L': grep_args.push_back( "-L" ); grep_list_mode = -1; break;
          case 'm': grep_args.push_back( "-m" ); grep_args.push_back( arg ); break;
          case 'n': grep_args.push_back( "-n" ); break;
          case 'o': grep_args.push_back( "-o" ); break;
          case 'q': grep_args.push_back( "-q" ); verbosity = -1; break;
          case 'r': recursive = true; break;
          case 's': grep_args.push_back( "-s" ); verbosity = -1; break;
          case 'v': grep_args.push_back( "-v" ); break;
          case 'V': show_version( "Zgrep" ); return 0;
          case 'w': grep_args.push_back( "-w" ); break;
          case 'x': grep_args.push_back( "-x" ); break;
          case help_opt    : show_zgrep_help(); return 0;
          case verbose_opt : if( verbosity < 4 ) ++verbosity; break;
          case zgrep_opt   : break;
          default : internal_error( "uncaught option" );
          } break;
      case m_ztest:
        switch( code )
          {
          case 'h': show_ztest_help(); return 0;
          case 'q': verbosity = -1; ztest_args.push_back( "-q" ); break;
          case 'r': recursive = true; break;
          case 'v': if( verbosity < 4 ) ++verbosity;
                    ztest_args.push_back( "-v" ); break;
          case 'V': show_version( "Ztest" ); return 0;
          case ztest_opt : break;
          default : internal_error( "uncaught option" );
          } break;
      }
    } // end process options

  if( program_mode == m_zgrep && !grep_pattern_found )
    { show_error( "Pattern not found." ); return 2; }

  for( ; argind < parser.arguments(); ++argind )
    filenames.push_back( parser.argument( argind ) );

  if( filenames.empty() ) filenames.push_back("-");

  if( grep_show_name < 0 )
    grep_show_name = ( filenames.size() != 1 || recursive );

  int retval = ( program_mode == m_zgrep ) ? 1 : 0;
  while( !filenames.empty() )
    {
    input_filename = filenames.front();
    filenames.pop_front();
    if( !input_filename.size() || input_filename == "-" )
      {
      input_filename.clear();
      infd = STDIN_FILENO;
      }
    else
      {
      if( recursive )
        {
        struct stat st;
        if( stat( input_filename.c_str(), &st ) == 0 && S_ISDIR( st.st_mode ) )
          {
          DIR * const dirp = opendir( input_filename.c_str() );
          if( !dirp )
            {
            show_error2( "Can't open directory", input_filename.c_str() );
            if( retval < 1 ) retval = 1; continue;
            }
          std::list< std::string > tmp_list;
          while( true )
            {
            const struct dirent * const entryp = readdir( dirp );
            if( !entryp ) { closedir( dirp ); break; }
            std::string tmp_name( entryp->d_name );
            if( tmp_name != "." && tmp_name != ".." )
              tmp_list.push_back( input_filename + "/" + tmp_name );
            }
          filenames.splice( filenames.begin(), tmp_list );
          continue;
          }
        }
      infd = open_instream( input_filename, program_mode, format_index < 0 );
      if( infd < 0 ) { if( retval < 1 ) retval = 1; continue; }
      }

    int tmp = 0;
    switch( program_mode )
      {
      case m_none:
        break;
      case m_zcat:
        tmp = cat( infd, format_index, input_filename, cat_options );
        break;
      case m_zgrep:
        if( infd == STDIN_FILENO )
          tmp = zgrep_stdin( infd, format_index, grep_args );
        else tmp = zgrep_file( infd, format_index, input_filename, grep_args,
                               grep_list_mode, grep_show_name );
        break;
      case m_ztest:
        if( infd == STDIN_FILENO )
          tmp = ztest_stdin( infd, format_index, ztest_args );
        else tmp = ztest_file( infd, format_index, input_filename, ztest_args );
        break;
      }
    if( program_mode == m_zgrep )
      { if( tmp == 0 || ( tmp == 2 && retval == 1 ) ) retval = tmp; }
    else if( tmp > retval ) retval = tmp;

    if( input_filename.size() )
      { close( infd ); infd = -1; }
    }

  if( std::fclose( stdout ) != 0 )
    {
    show_error( "Can't close stdout", errno );
    switch( program_mode )
      {
      case m_none: break;
      case m_zcat: retval = 1; break;
      case m_zgrep: if( retval != 0 || verbosity >= 0 ) retval = 2; break;
      case m_ztest: if( retval == 0 ) retval = 1; break;
      }
    }
  return retval;
  }