#include <u.h>
#include <libc.h>
#include <bio.h>
#include <draw.h>
#include <event.h>

/* In honor of Jocelyn Bell Burnell, who deserved the Nobel. */

/* TODO:
 *	Resize the initial window, if we can make everything fit.
 */

/* Space between lines, multiplier on x & y spacing, line thickness. */
int offset, magx, magy, thick;

#define	NCOLORS 6
Image	*cols[NCOLORS][3];

/* NLINES and LINELEN match the original pulsar data. */
#define	NLINES 80
#define	LINELEN 300

static float pulsar[NLINES][LINELEN];

void
drawline(int i)
{
	int n, baseline;
	int hmargin = 10;
	int vmargin = 150;
	Point new, prev, start;

	hmargin = (screen->r.max.x - screen->r.min.x - LINELEN*magx)/2;

	baseline = screen->r.min.y+vmargin+NLINES*offset;
	prev = start = addpt(screen->r.min, Pt(hmargin, vmargin+offset*i));

	for(n = 0; n < LINELEN; n++) {
		new = addpt(start, Pt(magx*n, magy*-pulsar[i][n]));
		line(screen, prev, new, Endsquare, Endsquare,
			thick, cols[i%NCOLORS][2], ZP);
		line(screen, new, Pt(new.x, baseline), Endsquare, Endsquare,
			magx, cols[i%NCOLORS][1], ZP);
		prev = new;
	}
}

void
resize(void)
{
	int i;
	for(i = 0; i < NLINES; i++) {
		drawline(i);
		flushimage(display, 1);
	}
}

void
eresized(int new)
{
	if(new && getwindow(display, Refnone) < 0) {
		fprint(2, "%s: can't reattach to window\n", argv0);
		exits("reattach");
	}
	resize();
}

/* These colors are from stats.c.
 * Stats uses c0 for above the line, c1 for below, and c2 for the line.
 * I think using c0 fro below might look better here. */
void
mkcol(int i, int c0, int c1, int c2)
{
	cols[i][0] = allocimagemix(display, c0, DWhite);
	cols[i][1] = allocimage(display, Rect(0,0,1,1), CMAP8, 1, c1);
	cols[i][2] = allocimage(display, Rect(0,0,1,1), CMAP8, 1, c2);
}

void
colinit(void)
{
	/* Peach */
	mkcol(0, 0xFFAAAAFF, 0xFFAAAAFF, 0xBB5D5DFF);
	/* Aqua */
	mkcol(1, DPalebluegreen, DPalegreygreen, DPurpleblue);
	/* Yellow */
	mkcol(2, DPaleyellow, DDarkyellow, DYellowgreen);
	/* Green */
	mkcol(3, DPalegreen, DMedgreen, DDarkgreen);
	/* Blue */
	mkcol(4, 0x00AAFFFF, 0x00AAFFFF, 0x0088CCFF);
	/* Grey */
	cols[5][0] = allocimage(display, Rect(0,0,1,1), CMAP8, 1, 0xEEEEEEFF);
	cols[5][1] = allocimage(display, Rect(0,0,1,1), CMAP8, 1, 0xCCCCCCFF);
	cols[5][2] = allocimage(display, Rect(0,0,1,1), CMAP8, 1, 0x888888FF);
}

void
parsefile(char* f)
{
	Biobuf* b;
	char* line, *buf;
	int i, j;

	b = Bopen(f, OREAD);
	if(b == nil) {
		fprint(2, "%s: cannot open %s: %r\n", argv0, f);
		exits("open");
	}

	for(i=0; i<NLINES; i++) {
		line = Brdline(b, '\n');
		buf = strdup(line);
		pulsar[i][0] = atof(strtok(buf, ", "));
		for(j=1; j<LINELEN; j++) {
			pulsar[i][j] = atof(strtok(0, ", "));
		}
	}

	Bterm(b);
}

void
usage(void)
{
	fprint(2, "usage: %s [ -x n ] [-y n ] [ -o n ]\n", argv0);
	exits("usage");
}

void
main(int argc, char *argv[])
{
	/* See https://gist.githubusercontent.com/borgar/31c1e476b8e92a11d7e9/raw/0fae97dab6830ecee185a63c1cee0008f6778ff6/pulsar.csv */
	char* csv = smprint("%s/lib/pulsar.csv", getenv("home"));

	offset = 20;
	magx = magy = 5;
	thick = 2;
	Event e;

	ARGBEGIN{
		case 'f':
			csv = EARGF(usage());
			break;
		case 'o':
			offset = atoi(EARGF(usage()));
			break;
		case 't':
			thick = atoi(EARGF(usage()));
			break;
		case 'x':
			magx = atoi(EARGF(usage()));
			break;
		case 'y':
			magy = atoi(EARGF(usage()));
			break;
	}ARGEND

	if(initdraw(nil, nil, argv0) < 0){
		fprint(2, "%s: initdraw failed: %r\n", argv0);
		exits("initdraw");
	}

	/* This doesn't do what I want. How to get a black background? */
	screen->screen->fill = display->black;

	colinit();
	einit(Emouse);
	parsefile(csv);

	for (;;) {
		resize();
		switch(eread(Ekeyboard, &e)) {
			case Ekeyboard:
				if(e.kbdc==0x7F || e.kbdc=='q')
					exits(0);
				break;
		}
	}
}