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

#define nmax 100000
#define pi 3.14159265358979

FILE *out,*in;
/*  file of input parameter (*.txt) must be written as follows:
<number of sine waves>
<frequency-1> <level-1> <decrement rate-1> <phase-1>
<frequency-2> <level-2> <decrement rate-2> <phase-2>
<frequency-3> <level-3> <decrement rate-3> <phase-3>
....
<frequency-n> <level-n> <decrement rate-n> <phase-n>
where frequency as Hz, level as -dBV, decrement rate as -dBV/sec,
and phase as radian.
*/


int header(unsigned long ssize);

int main(int argc, char *argv[]){

	int k,kj,kmax;
	double *ofr,*level,*redu,*ph,*cullevel,*culofr,*culredu,*first;
	double param1,param2,param3,param4;
	double amax,u;
	signed short int is;
	double levelsum,stdlevel;
	unsigned char table[1];
	char outputfile[80],paramfile[80];
	u=(2.9999999*2.0)/pow(2.0,16.0);
	levelsum=0.0;
	switch (argc) {
		case 1 :
		/* read parameters from Console */
		printf("Input WAVE File Name.(Don't input extensions)\n");
		scanf("%s",outputfile);
		printf("Input number of specturum\n");
		scanf("%d",&kmax);
		if ((ofr=malloc(kmax*sizeof(double)))==NULL){
		  printf("\nOut of Memory Error!\n");
		  exit(1);};
		if ((level=malloc(kmax*sizeof(double)))==NULL){
		  printf("\nOut of Memory Error!\n");
		  exit(1);};
		if ((redu=malloc(kmax*sizeof(double)))==NULL){
		  printf("\nOut of Memory Error!\n");
		  exit(1);};
		if ((ph=malloc(kmax*sizeof(double)))==NULL){
		  printf("\nOut of Memory Error!\n");
		  exit(1);};
		printf("Input Freq, Level, R, phase\n");
		for (kj=0; kj<kmax; kj++){
			scanf("%f %f %f %f", &param1,&param2,&param3,&param4);
			ofr[kj]=param1;
			level[kj]=param2;
			redu[kj]=param3;
			ph[kj]=param4;
			levelsum=levelsum+pow(10.0,level[kj]/10.0);}
		break;
		case 2 :
		/* read parameters from File */
		strcpy(paramfile,argv[1]);
		strcpy(outputfile,paramfile);
		strcat(paramfile,".txt");
		if ((in = fopen(paramfile,"rt"))==0){
			printf("Can't open File %s\n",paramfile);
			exit(1);}
		fscanf(in,"%d",&kmax);
		if ((ofr=malloc(kmax*sizeof(double)))==NULL){
		  printf("\nOut of Memory Error!\n");
		  exit(1);};
		if ((level=malloc(kmax*sizeof(double)))==NULL){
		  printf("\nOut of Memory Error!\n");
		  exit(1);};
		if ((redu=malloc(kmax*sizeof(double)))==NULL){
		  printf("\nOut of Memory Error!\n");
		  exit(1);};
		if ((ph=malloc(kmax*sizeof(double)))==NULL){
		  printf("\nOut of Memory Error!\n");
		  exit(1);};
		for (kj=0; kj<kmax; kj++){
			fscanf(in,"%f %f %f %f",&param1,&param2,&param3,&param4);
			ofr[kj]=param1;
			level[kj]=param2;
			redu[kj]=param3;
			ph[kj]=param4;
			levelsum=levelsum+pow(10.0,level[kj]/10.0);}
		close(in);
		break;
		default :
			printf("Command-line Options are too many.\n");
			exit(1);
	}
	stdlevel=3.0/levelsum;
	if ((cullevel=malloc(kmax*sizeof(double)))==NULL){
	  printf("\nOut of Memory Error!\n");
	  exit(1);};
	if ((culofr=malloc(kmax*sizeof(double)))==NULL){
	  printf("\nOut of Memory Error!\n");
	  exit(1);};
	if ((culredu=malloc(kmax*sizeof(double)))==NULL){
	  printf("\nOut of Memory Error!\n");
	  exit(1);};
	if ((first=malloc(kmax*sizeof(double)))==NULL){
	  printf("\nOut of Memory Error!\n");
	  exit(1);};
 	for (kj=0; kj<kmax; kj++){
		cullevel[kj]=stdlevel*pow(10.0,level[kj]/10.0);
		culofr[kj]=ofr[kj]*pi*2.0/44100.0;
		culredu[kj]=-redu[kj]/10.0*log(10.0)/44100.0;
		first[kj]=(-6*log(10)-cullevel[kj])/0.04/44100;}

	strcat(outputfile,".wav");
	out = fopen(outputfile,"wb");
	printf("Now creating %s ....\n",outputfile);
	header(nmax);

	/* attack */
	for (k=1764; k>=0; k--){
		amax=0;
		for (kj=0; kj<kmax; kj++){
			amax+=exp(k*first[kj])*cullevel[kj]*sin(culofr[kj]*k+ph[kj]+pi);}
		is=(signed short)(amax/u);
		table[1]=is >> 8;
		table[0]=(unsigned char)is;
		fwrite(table,sizeof(short),1,out);
	}

	/* main decay */
	for (k=1; k<=nmax-1765; k++){
		amax=0;
		for (kj=0; kj<kmax; kj++){
			amax+=exp(k*culredu[kj])*cullevel[kj]*sin(culofr[kj]*k+ph[kj]);}
		is=(signed short)(amax/u);
		table[1]=is >> 8;
		table[0]=(unsigned char)is;
		fwrite(table,sizeof(short),1,out);
	}
	close(out);
	free(ofr);
	free(level);
	free(redu);
	free(ph);
	free(cullevel);
	free(culofr);
	free(culredu);
	free(first);
	return(0);
}

int header(unsigned long ssize){
	/*  Microsoft Windows Waveform File Header */
	
	unsigned char ckSize[3],vchar[1],vdchar[3];
	unsigned long vdw;
	unsigned short vw;
	char ck[5];
	
	char *str1 = "RIFF";
	char *str2 = "WAVE";
	char *str3 = "fmt ";
	char *str4 = "data";
	
	/* RIFF chank */
	strcpy(ck,str1);
	fwrite(ck,sizeof(long),1,out);
	ckSize[0]=(unsigned char)(ssize*2+36);
	ckSize[1]=(ssize*2+16) >> 8;
	ckSize[2]=(ssize*2+16) >> 16;
	ckSize[3]=(ssize*2+16) >> 24;
	fwrite(ckSize,sizeof(long),1,out);
		/* WAVE chank */
		strcpy(ck,str2);
		fwrite(ck,sizeof(int),1,out);
			/* format chank */
			strcpy(ck,str3);
			fwrite(ck,sizeof(int),1,out);
			vdw=16;
			ckSize[0]=(unsigned char)vdw;
			ckSize[1]=vdw >> 8;
			ckSize[2]=vdw >> 16;
			ckSize[3]=vdw >> 24;
			fwrite(ckSize,sizeof(long),1,out);
				/* Wave Format */
				vw=1;		/* wFormatTag */
				vchar[0]=(unsigned char)vw;
				vchar[1]=vw >> 8;
				fwrite(vchar,sizeof(short),1,out);
				vw=1;		/* nChannels */
				vchar[0]=(unsigned char)vw;
				vchar[1]=vw >> 8;
				fwrite(vchar,sizeof(short),1,out);
				vdw=44100;	/* nSamplesPerSec */
				vdchar[0]=(unsigned char)vdw;
				vdchar[1]=vdw >> 8;
				vdchar[2]=vdw >> 16;
				vdchar[3]=vdw >> 24;
				fwrite(vdchar,sizeof(long),1,out);
				vdw=88200;	/* nAvgBytesPerSec */
				vdchar[0]=(unsigned char)vdw;
				vdchar[1]=vdw >> 8;
				vdchar[2]=vdw >> 16;
				vdchar[3]=vdw >> 24;
				fwrite(vdchar,sizeof(long),1,out);
				vw=2;		/* nBlockAlign */
				vchar[0]=(unsigned char)vw;
				vchar[1]=vw >> 8;
				fwrite(vchar,sizeof(short),1,out);
				/* FormatSpecific */
				vw=16;		/* nBitsPerSample */
				vchar[0]=(unsigned char)vw;
				vchar[1]=vw >> 8;
				fwrite(vchar,sizeof(short),1,out);
			/* data chank */
			strcpy(ck,str4);
			fwrite(ck,sizeof(int),1,out);
			ckSize[0]=(unsigned char)(ssize*2);
			ckSize[1]=(ssize*2) >> 8;
			ckSize[2]=(ssize*2) >> 16;
			ckSize[3]=(ssize*2) >> 24;
			fwrite(ckSize,sizeof(long),1,out);
	return (0);
	}