/*
 * jpegtran.c
 *
 * Copyright (C) 1995, Thomas G. Lane.
 * This file is part of the Independent JPEG Group's software.
 * For conditions of distribution and use, see the accompanying README file.
 *
 * This file contains a command-line user interface for JPEG transcoding.
 * It is very similar to cjpeg.c, but provides lossless transcoding between
 * different JPEG file formats.
 */

#include "cdjpeg.h"      /* Common decls for cjpeg/djpeg applications */
#include "jversion.h"        /* for version message */

#ifdef USE_CCOMMAND     /* command-line reader for Macintosh */
#ifdef __MWERKS__
#include <SIOUX.h>              /* Metrowerks declares it here */
#endif
#ifdef THINK_C
#include <console.h>     /* Think declares it here */
#endif
#endif


/*
 * Argument-parsing code.
 * The switch parser is designed to be useful with DOS-style command line
 * syntax, ie, intermixed switches and file names, where only the switches
 * to the left of a given file name affect processing of that file.
 * The main program in this file doesn't actually use this capability...
 */


static const char * progname;   /* program name for error messages */
static char * outfilename;  /* for -outfile switch */


LOCAL void
usage( void ) {
/* complain about bad command line */
    fprintf( stderr, "usage: %s [switches] ", progname );
#ifdef TWO_FILE_COMMANDLINE
    fprintf( stderr, "inputfile outputfile\n" );
#else
    fprintf( stderr, "[inputfile]\n" );
#endif

    fprintf( stderr, "Switches (names may be abbreviated):\n" );
#ifdef ENTROPY_OPT_SUPPORTED
    fprintf( stderr, "  -optimize      Optimize Huffman table (smaller file, but slow compression)\n" );
#endif
#ifdef C_PROGRESSIVE_SUPPORTED
    fprintf( stderr, "  -progressive   Create progressive JPEG file\n" );
#endif
    fprintf( stderr, "Switches for advanced users:\n" );
    fprintf( stderr, "  -restart N     Set restart interval in rows, or in blocks with B\n" );
    fprintf( stderr, "  -maxmemory N   Maximum memory to use (in kbytes)\n" );
    fprintf( stderr, "  -outfile name  Specify name for output file\n" );
    fprintf( stderr, "  -verbose  or  -debug   Emit debug output\n" );
    fprintf( stderr, "Switches for wizards:\n" );
#ifdef C_ARITH_CODING_SUPPORTED
    fprintf( stderr, "  -arithmetic    Use arithmetic coding\n" );
#endif
#ifdef C_MULTISCAN_FILES_SUPPORTED
    fprintf( stderr, "  -scans file    Create multi-scan JPEG per script file\n" );
#endif
    exit( EXIT_FAILURE );
}


LOCAL int
parse_switches( j_compress_ptr cinfo, int argc, char ** argv,
                int last_file_arg_seen, boolean for_real ) {
/* Parse optional switches.
 * Returns argv[] index of first file-name argument (== argc if none).
 * Any file names with indexes <= last_file_arg_seen are ignored;
 * they have presumably been processed in a previous iteration.
 * (Pass 0 for last_file_arg_seen on the first or only iteration.)
 * for_real is FALSE on the first (dummy) pass; we may skip any expensive
 * processing.
 */
    int argn;
    char * arg;
    boolean simple_progressive;
    char * scansarg = NULL; /* saves -scans parm if any */

    /* Set up default JPEG parameters. */
    simple_progressive = FALSE;
    outfilename = NULL;
    cinfo->err->trace_level = 0;

    /* Scan command line options, adjust parameters */

    for ( argn = 1; argn < argc; argn++ ) {
        arg = argv[argn];
        if ( *arg != '-' ) {
            /* Not a switch, must be a file name argument */
            if ( argn <= last_file_arg_seen ) {
                outfilename = NULL;/* -outfile applies to just one input file */
                continue; /* ignore this name if previously processed */
            }
            break;      /* else done parsing switches */
        }
        arg++;      /* advance past switch marker character */

        if ( keymatch( arg, "arithmetic", 1 ) ) {
            /* Use arithmetic coding. */
#ifdef C_ARITH_CODING_SUPPORTED
            cinfo->arith_code = TRUE;
#else
            fprintf( stderr, "%s: sorry, arithmetic coding not supported\n",
                     progname );
            exit( EXIT_FAILURE );
#endif

        } else if ( keymatch( arg, "debug", 1 ) || keymatch( arg, "verbose", 1 ) ) {
            /* Enable debug printouts. */
            /* On first -d, print version identification */
            static boolean printed_version = FALSE;

            if ( !printed_version ) {
                fprintf( stderr, "Independent JPEG Group's JPEGTRAN, version %s\n%s\n",
                         JVERSION, JCOPYRIGHT );
                printed_version = TRUE;
            }
            cinfo->err->trace_level++;

        } else if ( keymatch( arg, "maxmemory", 3 ) ) {
            /* Maximum memory in Kb (or Mb with 'm'). */
            long lval;
            char ch = 'x';

            if ( ++argn >= argc ) {/* advance to next argument */
                usage();
            }
            if ( sscanf( argv[argn], "%ld%c", &lval, &ch ) < 1 ) {
                usage();
            }
            if ( ( ch == 'm' ) || ( ch == 'M' ) ) {
                lval *= 1000L;
            }
            cinfo->mem->max_memory_to_use = lval * 1000L;

        } else if ( keymatch( arg, "optimize", 1 ) || keymatch( arg, "optimise", 1 ) ) {
            /* Enable entropy parm optimization. */
#ifdef ENTROPY_OPT_SUPPORTED
            cinfo->optimize_coding = TRUE;
#else
            fprintf( stderr, "%s: sorry, entropy optimization was not compiled\n",
                     progname );
            exit( EXIT_FAILURE );
#endif

        } else if ( keymatch( arg, "outfile", 4 ) ) {
            /* Set output file name. */
            if ( ++argn >= argc ) {/* advance to next argument */
                usage();
            }
            outfilename = argv[argn];/* save it away for later use */

        } else if ( keymatch( arg, "progressive", 1 ) ) {
            /* Select simple progressive mode. */
#ifdef C_PROGRESSIVE_SUPPORTED
            simple_progressive = TRUE;
            /* We must postpone execution until num_components is known. */
#else
            fprintf( stderr, "%s: sorry, progressive output was not compiled\n",
                     progname );
            exit( EXIT_FAILURE );
#endif

        } else if ( keymatch( arg, "restart", 1 ) ) {
            /* Restart interval in MCU rows (or in MCUs with 'b'). */
            long lval;
            char ch = 'x';

            if ( ++argn >= argc ) {/* advance to next argument */
                usage();
            }
            if ( sscanf( argv[argn], "%ld%c", &lval, &ch ) < 1 ) {
                usage();
            }
            if ( ( lval < 0 ) || ( lval > 65535L ) ) {
                usage();
            }
            if ( ( ch == 'b' ) || ( ch == 'B' ) ) {
                cinfo->restart_interval = (unsigned int) lval;
                cinfo->restart_in_rows = 0;/* else prior '-restart n' overrides me */
            } else {
                cinfo->restart_in_rows = (int) lval;
                /* restart_interval will be computed during startup */
            }

        } else if ( keymatch( arg, "scans", 2 ) ) {
            /* Set scan script. */
#ifdef C_MULTISCAN_FILES_SUPPORTED
            if ( ++argn >= argc ) {/* advance to next argument */
                usage();
            }
            scansarg = argv[argn];
            /* We must postpone reading the file in case -progressive appears. */
#else
            fprintf( stderr, "%s: sorry, multi-scan output was not compiled\n",
                     progname );
            exit( EXIT_FAILURE );
#endif

        } else {
            usage();    /* bogus switch */
        }
    }

    /* Post-switch-scanning cleanup */

    if ( for_real ) {

#ifdef C_PROGRESSIVE_SUPPORTED
        if ( simple_progressive ) {/* process -progressive; -scans can override */
            jpeg_simple_progression( cinfo );
        }
#endif

#ifdef C_MULTISCAN_FILES_SUPPORTED
        if ( scansarg != NULL ) {/* process -scans if it was present */
            if ( !read_scan_script( cinfo, scansarg ) ) {
                usage();
            }
        }
#endif
    }

    return argn;        /* return index of next arg (file name) */
}


/*
 * The main program.
 */

GLOBAL int
main( int argc, char ** argv ) {
    struct jpeg_decompress_struct srcinfo;
    struct jpeg_compress_struct dstinfo;
    struct jpeg_error_mgr jsrcerr, jdsterr;
#ifdef PROGRESS_REPORT
    struct cdjpeg_progress_mgr progress;
#endif
    jvirt_barray_ptr * coef_arrays;
    int file_index;
    FILE * input_file;
    FILE * output_file;

    /* On Mac, fetch a command line. */
#ifdef USE_CCOMMAND
    argc = ccommand( &argv );
#endif

    progname = argv[0];
    if ( ( progname == NULL ) || ( progname[0] == 0 ) ) {
        progname = "jpegtran";
    }                       /* in case C library doesn't provide it */

    /* Initialize the JPEG decompression object with default error handling. */
    srcinfo.err = jpeg_std_error( &jsrcerr );
    jpeg_create_decompress( &srcinfo );
    /* Initialize the JPEG compression object with default error handling. */
    dstinfo.err = jpeg_std_error( &jdsterr );
    jpeg_create_compress( &dstinfo );

    /* Now safe to enable signal catcher.
     * Note: we assume only the decompression object will have virtual arrays.
     */
#ifdef NEED_SIGNAL_CATCHER
    enable_signal_catcher( ( j_common_ptr ) & srcinfo );
#endif

    /* Scan command line to find file names.
     * It is convenient to use just one switch-parsing routine, but the switch
     * values read here are ignored; we will rescan the switches after opening
     * the input file.
     */

    file_index = parse_switches( &dstinfo, argc, argv, 0, FALSE );
    jsrcerr.trace_level = jdsterr.trace_level;

#ifdef TWO_FILE_COMMANDLINE
    /* Must have either -outfile switch or explicit output file name */
    if ( outfilename == NULL ) {
        if ( file_index != argc - 2 ) {
            fprintf( stderr, "%s: must name one input and one output file\n",
                     progname );
            usage();
        }
        outfilename = argv[file_index + 1];
    } else {
        if ( file_index != argc - 1 ) {
            fprintf( stderr, "%s: must name one input and one output file\n",
                     progname );
            usage();
        }
    }
#else
    /* Unix style: expect zero or one file name */
    if ( file_index < argc - 1 ) {
        fprintf( stderr, "%s: only one input file\n", progname );
        usage();
    }
#endif /* TWO_FILE_COMMANDLINE */

    /* Open the input file. */
    if ( file_index < argc ) {
        if ( ( input_file = fopen( argv[file_index], READ_BINARY ) ) == NULL ) {
            fprintf( stderr, "%s: can't open %s\n", progname, argv[file_index] );
            exit( EXIT_FAILURE );
        }
    } else {
        /* default input file is stdin */
        input_file = read_stdin();
    }

    /* Open the output file. */
    if ( outfilename != NULL ) {
        if ( ( output_file = fopen( outfilename, WRITE_BINARY ) ) == NULL ) {
            fprintf( stderr, "%s: can't open %s\n", progname, outfilename );
            exit( EXIT_FAILURE );
        }
    } else {
        /* default output file is stdout */
        output_file = write_stdout();
    }

#ifdef PROGRESS_REPORT
    start_progress_monitor( ( j_common_ptr ) & dstinfo, &progress );
#endif

    /* Specify data source for decompression */
    jpeg_stdio_src( &srcinfo, input_file );

    /* Read file header */
    (void) jpeg_read_header( &srcinfo, TRUE );

    /* Read source file as DCT coefficients */
    coef_arrays = jpeg_read_coefficients( &srcinfo );

    /* Initialize destination compression parameters from source values */
    jpeg_copy_critical_parameters( &srcinfo, &dstinfo );

    /* Adjust default compression parameters by re-parsing the options */
    file_index = parse_switches( &dstinfo, argc, argv, 0, TRUE );

    /* Specify data destination for compression */
    jpeg_stdio_dest( &dstinfo, output_file );

    /* Start compressor */
    jpeg_write_coefficients( &dstinfo, coef_arrays );

    /* ought to copy source comments here... */

    /* Finish compression and release memory */
    jpeg_finish_compress( &dstinfo );
    jpeg_destroy_compress( &dstinfo );
    (void) jpeg_finish_decompress( &srcinfo );
    jpeg_destroy_decompress( &srcinfo );

    /* Close files, if we opened them */
    if ( input_file != stdin ) {
        fclose( input_file );
    }
    if ( output_file != stdout ) {
        fclose( output_file );
    }

#ifdef PROGRESS_REPORT
    end_progress_monitor( ( j_common_ptr ) & dstinfo );
#endif

    /* All done. */
    exit( jsrcerr.num_warnings + jdsterr.num_warnings ? EXIT_WARNING : EXIT_SUCCESS );
    return 0;       /* suppress no-return-value warnings */
}