// Josiah Boning
//
// project.c
// Main techlab executable

#include <stdio.h>
#include <stdlib.h>
#include <GL/glut.h>
#include <fftw3.h>
#include <math.h>

#define min(a,b) ((a)<(b))?(a):(b)
#define max(a,b) ((a)>(b))?(a):(b)
#define N 10000
#define ITEMS_PER_TRANS 1024

const double inf=1.0/0.0,ninf=-1.0/0.0;
double xmin,ymin,xmax,ymax;
double *datas;
fftw_complex **trans;
int numitems=0;
int numtrans=0;
int transsize=0;
int win_wave, win_spec, win_allspec;
double tmin, tmax;

void display(void) {
	int k, n;

	/* do waveform window */
	glutSetWindow(win_wave);

	glClear(GL_COLOR_BUFFER_BIT);
	glColor3f(1,1,1);

	glBegin(GL_LINES);
	glVertex3f(-1,0,0);
	glVertex3f(1,0,0);
	glVertex3f(0,-0.5,0);
	glVertex3f(0,0.5,0);
	glEnd();

	glColor3f(0.0,0.0,1.0);

	glBegin(GL_LINE_STRIP);
	for (k=0;k<numitems;k++) { 
		glVertex2f(((double)k)/numitems, ((double)datas[k])/255);
	}
	glEnd();
	glutSwapBuffers();

	/* single spectrum graph */
	glutSetWindow(win_spec);
	glClear(GL_COLOR_BUFFER_BIT);
	glBegin(GL_LINE_STRIP);
	glColor3f(1,0,0);
	n = 0;
	for (k=0; k < transsize; k++) {
		double x = ((double)k)/transsize;
		double val = pow(pow(((double)trans[n][k][0]),2)+pow(((double)trans[n][k][1]),2), 1.0/2)/(tmax-tmin);
		glColor3f(1,0,0);
		glVertex2f(((double)k)/transsize, val);
	}
	glEnd();
	glutSwapBuffers();

	/* sepctrum over time */
	glutSetWindow(win_allspec);
	glClear(GL_COLOR_BUFFER_BIT);
	glBegin(GL_POINTS);
	for (n=0; n < numtrans; n++) {
		for (k=0; k < transsize; k++) {
			double x = ((double)k)/transsize;
			double val = pow(pow(((double)trans[n][k][0]),2)+pow(((double)trans[n][k][1]),2), 1.0/2)/(tmax-tmin);
			glColor3f(val*255,0,0);
			glVertex2f(((double)n)/numtrans, ((double)k)/transsize);
		}
	}
	glEnd();
	glutSwapBuffers();
}

void showGraph(void) {
	glutInitDisplayMode(GLUT_DOUBLE|GLUT_RGB);

	glutInitWindowSize(400,300);
	glutInitWindowPosition(100,50);
	win_wave = glutCreateWindow("Waveform");
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	glOrtho(-0.1,1.1,-0.6,0.6,1.0,10.0);
	gluLookAt(0.0,0.0,5.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);

	glutInitWindowPosition(500,50);
	glutInitWindowSize(numtrans,300);
	win_allspec = glutCreateWindow("All Frequency Spectrums");
	glClearColor(0.0,1.0,0.0,0.0);
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	glOrtho(-0.0,1.0,-0.0,1.0,1.0,10.0);
	gluLookAt(0.0,0.0,5.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);

	glutInitWindowPosition(500+numtrans,50);
	glutInitWindowSize(400,300);
	win_spec = glutCreateWindow("Single Frequency Spectrum");
	glClearColor(1.0,1.0,1.0,0.0);
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	glOrtho(-0.1,1.1,-1.1,1.1,1.0,10.0);
	gluLookAt(0.0,0.0,5.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);

	glutDisplayFunc(display);
	glutMainLoop();
}

void readWav(char filename[]) {
	FILE* fin;
	char string[1024];
	int size, samplerate, byterate;
	short audiofmt, numchannels, blockalign, bitspersample;
	int i;
	unsigned char tmp;

	fin=fopen(filename,"r");

	fread(string, sizeof(char), 4, fin); // "RIFF"
	if (strncmp(string, "RIFF", 4)) {
		printf("Not a valid WAV file!\n");
		exit(0);
	}
	fread(string, sizeof(char), 4, fin);
	fread(string, sizeof(char), 4, fin); // "WAVE"
	if (strncmp(string, "WAVE", 4)) {
		printf("Not a valid WAV file!\n");
		exit(0);
	}
	fread(string, sizeof(char), 4, fin); // "fmt "
	if (strncmp(string, "fmt ", 4)) {
		printf("Not a valid WAV file!\n");
		exit(0);
	}

	fread(&size, sizeof(char), 4, fin);
	fread(&audiofmt, sizeof(char), 2, fin);
	if (audiofmt != 1) {
		printf("The WAV file must use PCM encoding.\n");
		exit(0);
	}
	fread(&numchannels, sizeof(char), 2, fin);
	if (numchannels != 1) {
		printf("The WAV file must be mono.\n");
		exit(0);
	}
	fread(&samplerate, sizeof(char), 4, fin);
	if (samplerate != 44100) {
		printf("The WAV file must have 44100 samples/sec.\n");
		exit(0);
	}
	fread(&byterate, sizeof(char), 4, fin);
	fread(&blockalign, sizeof(char), 2, fin);
	fread(&bitspersample, sizeof(char), 2, fin);
	if (bitspersample != 8) {
		printf("The WAV file must use 8-bit sampling.\n");
		exit(0);
	}

	fread(string, sizeof(char), 4, fin);
	if (strncmp(string, "data", 4)) {
		printf("Malformed WAV file.\n");
		exit(0);
	}
	fread(&size, sizeof(char), 4, fin);

	printf("%i\n", size);

	//size = 1 * ITEMS_PER_TRANS;
	numitems = size;
	numtrans = size / ITEMS_PER_TRANS;

	datas = (double*) fftw_malloc(size * sizeof(double));

	for (i = 0; i < numitems; i++) {
		fread(&tmp, sizeof(char), 1, fin);
		datas[i] = (double) tmp - 128;
	}

	fclose(fin);
}

void doTransforms() {
	int n;
	transsize = (ITEMS_PER_TRANS/2 + 1);
	trans = (fftw_complex**) fftw_malloc(numtrans * sizeof(fftw_complex*));
	for (n = 0; n < numtrans; n++) {
		trans[n] = (fftw_complex*) fftw_malloc(transsize * sizeof(fftw_complex));
		int t;
		double* index = datas+n*ITEMS_PER_TRANS;
		fftw_plan plan = fftw_plan_dft_r2c_1d(ITEMS_PER_TRANS, index, trans[n], FFTW_ESTIMATE);
		fftw_execute(plan);

		int i;
		tmin = inf;
		tmax = -inf;
		for (i = 0; i < transsize; i++) {
			double mag = pow(pow(trans[n][i][0],2) + pow(trans[n][i][1],2), 0.5);
			if (mag < tmin) {
				tmin = mag;
			}
			else if (mag > tmax) {
				tmax = mag;
			}
		}
	}
}

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

	xmin=ymin=inf;
	xmax=ymax=ninf;

	if (argc < 2) {
		printf("You must specify a WAV file!\n");
		exit(0);
	}

	readWav(argv[1]);
	doTransforms();

	showGraph();

	printf("here\n");

	fftw_free(datas);
	fftw_free(trans);

	exit(0);
}