/*

 *  mef2raw32.c
 * 
 
 Program to read mef format file (v.2) and save data as raw 32bit integers 
 Reads entire input file, decodes, and then saves entire output file. 
 
 Multiscale electrophysiology format example program

 
 To compile for a 64-bit intel system: (options will vary depending on your particular compiler and platform)
 Intel Compiler: icc mef2raw32.c mef_lib.c endian_functions.c AES_encryption.c RED_decode.c RED_encode.c crc_32.c -o mef2raw -fast -m64
 GCC: gcc mef2raw32.c mef_lib.c endian_functions.c AES_encryption.c RED_decode.c RED_encode.c crc_32.c -o mef2raw -O3 -arch x86_64
 
 For 32-bit systems write over size_types.h with size_types_32.h before compiling. You will also need to change
 compiler flags. 
 
 This software is made freely available under the GNU public license: http://www.gnu.org/licenses/gpl-3.0.txt
 
 Thanks to all who acknowledge the Mayo Systems Electrophysiology Laboratory, Rochester, MN
 in academic publications of their work facilitated by this software.
 
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "size_types.h"
#include "mef_header_2_0.h"
#include "RED_codec.h"


int main (int argc, const char * argv[]) {
	si4 i, num, numBlocks, l;
	si4 *data, *dp;
	ui8 numEntries, inDataLength, bytesDecoded, entryCounter;
	si1 password[16], outFileName[200], path[200], encryptionKey[240];
	ui1 *hdr_block, *in_data, *idp, *diff_buffer, *dbp;
	FILE *fp;
	MEF_HEADER_INFO header;
	RED_BLOCK_HDR_INFO RED_bk_hdr;
	void AES_KeyExpansion();

	
	
	memset(password, 0, 16);
	
	if (argc < 2 || argc > 4) 
	{
		(void) printf("USAGE: %s file_name [password] \n", argv[0]);
		return(1);
	}
		
	if (argc > 2) { //check input arguments for password
		strncpy(password, argv[2], 16);
	}
	
	//allocate memory for (encrypted) header block
	hdr_block = calloc(sizeof(ui1), MEF_HEADER_LENGTH);
	
	fp = fopen(argv[1], "r");
	if (fp == NULL) {
		fprintf(stderr, "Error opening file %s\n", argv[1]);
		return 1;
	}

	num = fread(hdr_block, 1, MEF_HEADER_LENGTH, fp);
	if (num != MEF_HEADER_LENGTH) {
		fprintf(stderr, "Error reading file %s\n", argv[1]);
		return 1;
	}
		
	read_mef_header_block(hdr_block, &header, password);

	if (header.session_encryption_used && validate_password(hdr_block, password)==0) {
		fprintf(stderr, "Can not decrypt MEF header\n");
		free(hdr_block);
		return 1;
	}

	numBlocks = header.number_of_index_entries;
	numEntries = header.number_of_samples;
	inDataLength = header.index_data_offset - header.header_length;
	if (header.data_encryption_used) {
		AES_KeyExpansion(4, 10, encryptionKey, header.session_password); 
	}
	else
		*encryptionKey = 0;

	free(hdr_block);
	
	diff_buffer = malloc(header.maximum_block_length * 4);
	in_data = malloc(inDataLength);
	data = calloc(sizeof(ui4), numEntries);
	if (data == NULL || in_data == NULL || diff_buffer == NULL) {
		fprintf(stderr, "malloc error\n");
		return 1;
	}

	fprintf(stdout, "\n\nReading file %s \n", argv[1]);
	num = fread(in_data, 1, inDataLength, fp);
	if (num != inDataLength) {
		fprintf(stderr, "Data read error \n");
		return 1;
	}
	fclose(fp);
	
	fprintf(stdout, "Starting decompression loop with %d blocks\n", numBlocks);
	
	dp = data;	idp = in_data;	dbp = diff_buffer;
	entryCounter = 0;
	for (i=0; i<numBlocks; i++)
	{
		bytesDecoded = RED_decompress_block(idp, dp, dbp, encryptionKey, 0, &RED_bk_hdr);
		idp += bytesDecoded;
		dp += RED_bk_hdr.sample_count;
		dbp = diff_buffer; //don't need to save diff_buffer- write over
		entryCounter += RED_bk_hdr.sample_count;

	}
	free(in_data); in_data = NULL;
	free(diff_buffer); diff_buffer = NULL;
	fprintf(stdout, "Decompression complete\n");
	
	//Assemble output filename
	l = (int)strlen(argv[1]);
	memcpy(path, argv[1], l-4);
	path[l-4] = '\0';
	sprintf(outFileName, "%s.raw32", path);
	
	fp = fopen(outFileName, "w");
	if (fp == NULL) {
		fprintf(stderr, "Error opening file %s\n", outFileName);
		return 1;
	}
	fprintf(stdout, "\n\nWriting file %s: %ld entries \n", outFileName, entryCounter);
	num = fwrite(data, sizeof(si4), entryCounter, fp);
	if (num != entryCounter) {
		fprintf(stderr, "Error writing file %s\n", argv[1]);
		return 1;
	}
	fclose(fp);

	free(data);
	return 0;
}