/*
 * rdswitch.c
 *
 * This file was part of the Independent JPEG Group's software:
 * Copyright (C) 1991-1996, Thomas G. Lane.
 * libjpeg-turbo Modifications:
 * Copyright (C) 2010, D. R. Commander.
 * For conditions of distribution and use, see the accompanying README.ijg
 * file.
 *
 * This file contains routines to process some of cjpeg's more complicated
 * command-line switches.  Switches processed here are:
 *      -qtables file           Read quantization tables from text file
 *      -scans file             Read scan script from text file
 *      -quality N[,N,...]      Set quality ratings
 *      -qslots N[,N,...]       Set component quantization table selectors
 *      -sample HxV[,HxV,...]   Set component sampling factors
 */

#include "cdjpeg.h"             /* Common decls for cjpeg/djpeg applications */
#include <ctype.h>              /* to declare isdigit(), isspace() */


LOCAL(int)
text_getc(FILE *file)
/* Read next char, skipping over any comments (# to end of line) */
/* A comment/newline sequence is returned as a newline */
{
	register int ch;

	ch = getc(file);
	if (ch == '#') {
		do {
			ch = getc(file);
		} while (ch != '\n' && ch != EOF);
	}
	return ch;
}


LOCAL(boolean)
read_text_integer(FILE *file, long *result, int *termchar)
/* Read an unsigned decimal integer from a file, store it in result */
/* Reads one trailing character after the integer; returns it in termchar */
{
	register int ch;
	register long val;

	/* Skip any leading whitespace, detect EOF */
	do {
		ch = text_getc(file);
		if (ch == EOF) {
			*termchar = ch;
			return FALSE;
		}
	} while (isspace(ch));

	if (!isdigit(ch)) {
		*termchar = ch;
		return FALSE;
	}

	val = ch - '0';
	while ((ch = text_getc(file)) != EOF) {
		if (!isdigit(ch))
			break;
		val *= 10;
		val += ch - '0';
	}
	*result = val;
	*termchar = ch;
	return TRUE;
}


#if JPEG_LIB_VERSION < 70
static int q_scale_factor[NUM_QUANT_TBLS] = {100, 100, 100, 100};
#endif

GLOBAL(boolean)
read_quant_tables(j_compress_ptr cinfo, char *filename,
                  boolean force_baseline)
/* Read a set of quantization tables from the specified file.
 * The file is plain ASCII text: decimal numbers with whitespace between.
 * Comments preceded by '#' may be included in the file.
 * There may be one to NUM_QUANT_TBLS tables in the file, each of 64 values.
 * The tables are implicitly numbered 0,1,etc.
 * NOTE: does not affect the qslots mapping, which will default to selecting
 * table 0 for luminance (or primary) components, 1 for chrominance components.
 * You must use -qslots if you want a different component->table mapping.
 */
{
	FILE *fp;
	int tblno, i, termchar;
	long val;
	unsigned int table[DCTSIZE2];

	if ((fp = fopen(filename, "r")) == NULL) {
		fprintf(stderr, "Can't open table file %s\n", filename);
		return FALSE;
	}
	tblno = 0;

	while (read_text_integer(fp, &val, &termchar)) { /* read 1st element of table */
		if (tblno >= NUM_QUANT_TBLS) {
			fprintf(stderr, "Too many tables in file %s\n", filename);
			fclose(fp);
			return FALSE;
		}
		table[0] = (unsigned int) val;
		for (i = 1; i < DCTSIZE2; i++) {
			if (!read_text_integer(fp, &val, &termchar)) {
				fprintf(stderr, "Invalid table data in file %s\n", filename);
				fclose(fp);
				return FALSE;
			}
			table[i] = (unsigned int) val;
		}
#if JPEG_LIB_VERSION >= 70
		jpeg_add_quant_table(cinfo, tblno, table, cinfo->q_scale_factor[tblno],
							 force_baseline);
#else
		jpeg_add_quant_table(cinfo, tblno, table, q_scale_factor[tblno],
		                     force_baseline);
#endif
		tblno++;
	}

	if (termchar != EOF) {
		fprintf(stderr, "Non-numeric data in file %s\n", filename);
		fclose(fp);
		return FALSE;
	}

	fclose(fp);
	return TRUE;
}


#ifdef C_MULTISCAN_FILES_SUPPORTED

LOCAL(boolean)
read_scan_integer(FILE *file, long *result, int *termchar)
/* Variant of read_text_integer that always looks for a non-space termchar;
 * this simplifies parsing of punctuation in scan scripts.
 */
{
	register int ch;

	if (!read_text_integer(file, result, termchar))
		return FALSE;
	ch = *termchar;
	while (ch != EOF && isspace(ch))
		ch = text_getc(file);
	if (isdigit(ch)) {            /* oops, put it back */
		if (ungetc(ch, file) == EOF)
			return FALSE;
		ch = ' ';
	} else {
		/* Any separators other than ';' and ':' are ignored;
		 * this allows user to insert commas, etc, if desired.
		 */
		if (ch != EOF && ch != ';' && ch != ':')
			ch = ' ';
	}
	*termchar = ch;
	return TRUE;
}


GLOBAL(boolean)
read_scan_script(j_compress_ptr cinfo, char *filename)
/* Read a scan script from the specified text file.
 * Each entry in the file defines one scan to be emitted.
 * Entries are separated by semicolons ';'.
 * An entry contains one to four component indexes,
 * optionally followed by a colon ':' and four progressive-JPEG parameters.
 * The component indexes denote which component(s) are to be transmitted
 * in the current scan.  The first component has index 0.
 * Sequential JPEG is used if the progressive-JPEG parameters are omitted.
 * The file is free format text: any whitespace may appear between numbers
 * and the ':' and ';' punctuation marks.  Also, other punctuation (such
 * as commas or dashes) can be placed between numbers if desired.
 * Comments preceded by '#' may be included in the file.
 * Note: we do very little validity checking here;
 * jcmaster.c will validate the script parameters.
 */
{
	FILE *fp;
	int scanno, ncomps, termchar;
	long val;
	jpeg_scan_info *scanptr;
#define MAX_SCANS  100          /* quite arbitrary limit */
	jpeg_scan_info scans[MAX_SCANS];

	if ((fp = fopen(filename, "r")) == NULL) {
		fprintf(stderr, "Can't open scan definition file %s\n", filename);
		return FALSE;
	}
	scanptr = scans;
	scanno = 0;

	while (read_scan_integer(fp, &val, &termchar)) {
		if (scanno >= MAX_SCANS) {
			fprintf(stderr, "Too many scans defined in file %s\n", filename);
			fclose(fp);
			return FALSE;
		}
		scanptr->component_index[0] = (int) val;
		ncomps = 1;
		while (termchar == ' ') {
			if (ncomps >= MAX_COMPS_IN_SCAN) {
				fprintf(stderr, "Too many components in one scan in file %s\n",
				        filename);
				fclose(fp);
				return FALSE;
			}
			if (!read_scan_integer(fp, &val, &termchar))
				goto bogus;
			scanptr->component_index[ncomps] = (int) val;
			ncomps++;
		}
		scanptr->comps_in_scan = ncomps;
		if (termchar == ':') {
			if (!read_scan_integer(fp, &val, &termchar) || termchar != ' ')
				goto bogus;
			scanptr->Ss = (int) val;
			if (!read_scan_integer(fp, &val, &termchar) || termchar != ' ')
				goto bogus;
			scanptr->Se = (int) val;
			if (!read_scan_integer(fp, &val, &termchar) || termchar != ' ')
				goto bogus;
			scanptr->Ah = (int) val;
			if (!read_scan_integer(fp, &val, &termchar))
				goto bogus;
			scanptr->Al = (int) val;
		} else {
			/* set non-progressive parameters */
			scanptr->Ss = 0;
			scanptr->Se = DCTSIZE2 - 1;
			scanptr->Ah = 0;
			scanptr->Al = 0;
		}
		if (termchar != ';' && termchar != EOF) {
			bogus:
			fprintf(stderr, "Invalid scan entry format in file %s\n", filename);
			fclose(fp);
			return FALSE;
		}
		scanptr++, scanno++;
	}

	if (termchar != EOF) {
		fprintf(stderr, "Non-numeric data in file %s\n", filename);
		fclose(fp);
		return FALSE;
	}

	if (scanno > 0) {
		/* Stash completed scan list in cinfo structure.
		 * NOTE: for cjpeg's use, JPOOL_IMAGE is the right lifetime for this data,
		 * but if you want to compress multiple images you'd want JPOOL_PERMANENT.
		 */
		scanptr = (jpeg_scan_info *)
				(*cinfo->mem->alloc_small)((j_common_ptr) cinfo, JPOOL_IMAGE,
				                           scanno * sizeof(jpeg_scan_info));
		MEMCOPY(scanptr, scans, scanno * sizeof(jpeg_scan_info));
		cinfo->scan_info = scanptr;
		cinfo->num_scans = scanno;
	}

	fclose(fp);
	return TRUE;
}

#endif /* C_MULTISCAN_FILES_SUPPORTED */


#if JPEG_LIB_VERSION < 70
/* These are the sample quantization tables given in JPEG spec section K.1.
 * The spec says that the values given produce "good" quality, and
 * when divided by 2, "very good" quality.
 */
static const unsigned int std_luminance_quant_tbl[DCTSIZE2] = {
		16, 11, 10, 16, 24, 40, 51, 61,
		12, 12, 14, 19, 26, 58, 60, 55,
		14, 13, 16, 24, 40, 57, 69, 56,
		14, 17, 22, 29, 51, 87, 80, 62,
		18, 22, 37, 56, 68, 109, 103, 77,
		24, 35, 55, 64, 81, 104, 113, 92,
		49, 64, 78, 87, 103, 121, 120, 101,
		72, 92, 95, 98, 112, 100, 103, 99
};
static const unsigned int std_chrominance_quant_tbl[DCTSIZE2] = {
		17, 18, 24, 47, 99, 99, 99, 99,
		18, 21, 26, 66, 99, 99, 99, 99,
		24, 26, 56, 99, 99, 99, 99, 99,
		47, 66, 99, 99, 99, 99, 99, 99,
		99, 99, 99, 99, 99, 99, 99, 99,
		99, 99, 99, 99, 99, 99, 99, 99,
		99, 99, 99, 99, 99, 99, 99, 99,
		99, 99, 99, 99, 99, 99, 99, 99
};


LOCAL(void)
jpeg_default_qtables(j_compress_ptr cinfo, boolean force_baseline) {
	jpeg_add_quant_table(cinfo, 0, std_luminance_quant_tbl,
	                     q_scale_factor[0], force_baseline);
	jpeg_add_quant_table(cinfo, 1, std_chrominance_quant_tbl,
	                     q_scale_factor[1], force_baseline);
}

#endif


GLOBAL(boolean)
set_quality_ratings(j_compress_ptr cinfo, char *arg, boolean force_baseline)
/* Process a quality-ratings parameter string, of the form
 *     N[,N,...]
 * If there are more q-table slots than parameters, the last value is replicated.
 */
{
	int val = 75;                 /* default value */
	int tblno;
	char ch;

	for (tblno = 0; tblno < NUM_QUANT_TBLS; tblno++) {
		if (*arg) {
			ch = ',';                 /* if not set by sscanf, will be ',' */
			if (sscanf(arg, "%d%c", &val, &ch) < 1)
				return FALSE;
			if (ch != ',')            /* syntax check */
				return FALSE;
			/* Convert user 0-100 rating to percentage scaling */
#if JPEG_LIB_VERSION >= 70
			cinfo->q_scale_factor[tblno] = jpeg_quality_scaling(val);
#else
			q_scale_factor[tblno] = jpeg_quality_scaling(val);
#endif
			while (*arg && *arg++ != ',') /* advance to next segment of arg string */
				;
		} else {
			/* reached end of parameter, set remaining factors to last value */
#if JPEG_LIB_VERSION >= 70
			cinfo->q_scale_factor[tblno] = jpeg_quality_scaling(val);
#else
			q_scale_factor[tblno] = jpeg_quality_scaling(val);
#endif
		}
	}
	jpeg_default_qtables(cinfo, force_baseline);
	return TRUE;
}


GLOBAL(boolean)
set_quant_slots(j_compress_ptr cinfo, char *arg)
/* Process a quantization-table-selectors parameter string, of the form
 *     N[,N,...]
 * If there are more components than parameters, the last value is replicated.
 */
{
	int val = 0;                  /* default table # */
	int ci;
	char ch;

	for (ci = 0; ci < MAX_COMPONENTS; ci++) {
		if (*arg) {
			ch = ',';                 /* if not set by sscanf, will be ',' */
			if (sscanf(arg, "%d%c", &val, &ch) < 1)
				return FALSE;
			if (ch != ',')            /* syntax check */
				return FALSE;
			if (val < 0 || val >= NUM_QUANT_TBLS) {
				fprintf(stderr, "JPEG quantization tables are numbered 0..%d\n",
				        NUM_QUANT_TBLS - 1);
				return FALSE;
			}
			cinfo->comp_info[ci].quant_tbl_no = val;
			while (*arg && *arg++ != ',') /* advance to next segment of arg string */
				;
		} else {
			/* reached end of parameter, set remaining components to last table */
			cinfo->comp_info[ci].quant_tbl_no = val;
		}
	}
	return TRUE;
}


GLOBAL(boolean)
set_sample_factors(j_compress_ptr cinfo, char *arg)
/* Process a sample-factors parameter string, of the form
 *     HxV[,HxV,...]
 * If there are more components than parameters, "1x1" is assumed for the rest.
 */
{
	int ci, val1, val2;
	char ch1, ch2;

	for (ci = 0; ci < MAX_COMPONENTS; ci++) {
		if (*arg) {
			ch2 = ',';                /* if not set by sscanf, will be ',' */
			if (sscanf(arg, "%d%c%d%c", &val1, &ch1, &val2, &ch2) < 3)
				return FALSE;
			if ((ch1 != 'x' && ch1 != 'X') || ch2 != ',') /* syntax check */
				return FALSE;
			if (val1 <= 0 || val1 > 4 || val2 <= 0 || val2 > 4) {
				fprintf(stderr, "JPEG sampling factors must be 1..4\n");
				return FALSE;
			}
			cinfo->comp_info[ci].h_samp_factor = val1;
			cinfo->comp_info[ci].v_samp_factor = val2;
			while (*arg && *arg++ != ',') /* advance to next segment of arg string */
				;
		} else {
			/* reached end of parameter, set remaining components to 1x1 sampling */
			cinfo->comp_info[ci].h_samp_factor = 1;
			cinfo->comp_info[ci].v_samp_factor = 1;
		}
	}
	return TRUE;
}
