shithub: candlestick

Download patch

ref: b7ec8469463c8de77f733578f9b874a8771529ed
author: phil9 <telephil9@gmail.com>
date: Tue Jan 25 01:16:16 EST 2022 

initial import


--- /dev/null
+++ b/LICENSE
@@ -1,0 +1,21 @@
+MIT License
+
+Copyright (c) 2022 phil9 <telephil9@gmail.com>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
--- /dev/null
+++ b/README.md
@@ -1,0 +1,19 @@
+# candlestick
+
+A candlestick chart widget to view historical financial data.  
+This has been tested with data downloaded from [yahoo finance](https://finance.yahoo.com/) (see download link at [MSFT](https://finance.yahoo.com/quote/MSFT/history?p=MSFT)). This should work with any source provided the input is a CSV file with fields in the following order: <YYYY-MM-DD>,<Open>,<High>,<Low>,<Close>.
+
+![screenshot](candlestick.png)
+
+Chart title is set through the `-t` parameter.  
+Scrolling is performed using left and right arrows.  
+
+## quick start
+```sh
+% mk install
+% cat data.csv |candlestick -t 'MSFT 1Y'
+```
+
+## license
+MIT
+
--- /dev/null
+++ b/a.h
@@ -1,0 +1,25 @@
+typedef struct Chart Chart;
+typedef struct Price Price;
+
+struct Price
+{
+	Tm date;
+	double open;
+	double close;
+	double high;
+	double low;
+};
+
+enum
+{
+	Maxprices = 1024,
+};
+
+struct Chart
+{
+	Price prices[Maxprices];
+	usize nprices;
+	double ymin;
+	double ymax;
+};
+
--- /dev/null
+++ b/candlestick.c
@@ -1,0 +1,355 @@
+#include <u.h>
+#include <libc.h>
+#include <bio.h>
+#include <thread.h>
+#include <draw.h>
+#include <mouse.h>
+#include <keyboard.h>
+#include "a.h"
+
+enum
+{
+	BACK,
+	TEXT,
+	AXIS,
+	DIVS,
+	LINE,
+	BULL,
+	BEAR,
+	NCOLS,
+};
+
+enum
+{
+	Padding = 4,
+};
+
+Chart chart;
+char *title = "^FCHI";
+Mousectl *mc;
+Keyboardctl *kc;
+Image *cols[NCOLS];
+Font *afont;
+Rectangle chartr;
+Rectangle arear;
+Point pmin;
+Point pmax;
+Point pt;
+Point pl;
+int offset;
+int maxprices;
+
+#define MIN(x,y) ((x) < (y) ? (x) : (y))
+#define MAX(x,y) ((x) > (y) ? (x) : (y))
+
+double
+parsedouble(char *s)
+{
+	char *e;
+	double d;
+
+	d = strtod(s, &e);
+	if(e == nil || e == s)
+		return -1;
+	return d;
+}
+
+void
+loadprices(Chart *chart, int fd)
+{
+	Biobuf *bp;
+	char *s, *f[5];
+	int n, l;
+	Price *price;
+
+	bp = Bfdopen(fd, OREAD);
+	if(bp == nil)
+		sysfatal("Bfdopen: %r");
+	chart->ymin = 1000000000;
+	chart->ymax = 0.0;
+	for(l = 0; ;l++){
+		s = Brdstr(bp, '\n', 1);
+		if(s == nil)
+			break;
+		n = getfields(s, f, nelem(f), 0, ",");
+		if(n != 5){
+			fprint(2, "invalid input at line %d\n", l+1);
+			continue;
+		}
+		price = &chart->prices[chart->nprices];
+		if(tmparse(&price->date, "YYYY-MM-DD", f[0], nil, nil) == nil){
+			fprint(2, "invalid date '%s' at line %d\n", f[0], l+1);
+			continue;
+		}
+		price->open  = parsedouble(f[1]);
+		price->high  = parsedouble(f[2]);
+		price->low   = parsedouble(f[3]);
+		price->close = parsedouble(f[4]);
+		chart->ymin  = MIN(chart->ymin, price->low);
+		chart->ymax  = MAX(chart->ymax, price->high);
+		chart->nprices += 1;
+	}
+	if(chart->nprices == 0)
+		sysfatal("could not parse input");
+}
+
+Point
+stringdbl(Image *b, Point p, Image *c, Point sp, Font *f, double d)
+{
+	char buf[32] = {0};
+
+	snprint(buf, sizeof buf, "%f", d);
+	return string(b, p, c, sp, f, buf);
+}
+
+void
+drawlegend(Price *price)
+{
+	char buf[255] = {0};
+	Point p;
+	Image *c;
+
+	p = Pt(chartr.max.x, chartr.min.y - 1);
+	draw(screen, Rpt(pl, p), cols[BACK], nil, ZP);
+	if(price == nil){
+		flushimage(display, 1);
+		return;
+	}
+	c = price->open < price->close ? cols[BULL] : cols[BEAR];
+	p = pl;
+	if(title != nil)
+		p = string(screen, p, cols[TEXT], ZP, font, " - ");
+	snprint(buf, sizeof buf, "%τ", tmfmt(&price->date, "DD/MM/YYYY"));
+	p = string(screen, p, cols[TEXT], ZP, font, buf);
+	p = string(screen, p, cols[TEXT], ZP, font, " O:");
+	p = stringdbl(screen, p, c, ZP, font, price->open);
+	p = string(screen, p, cols[TEXT], ZP, font, " H:");
+	p = stringdbl(screen, p, c, ZP, font, price->high);
+	p = string(screen, p, cols[TEXT], ZP, font, " L:");
+	p = stringdbl(screen, p, c, ZP, font, price->low);
+	p = string(screen, p, cols[TEXT], ZP, font, " C:");
+	p = stringdbl(screen, p, c, ZP, font, price->close);
+	flushimage(display, 1);
+}
+
+void
+drawyaxis(void)
+{
+	char buf[32] = {0};
+	Point p, q;
+	int i, n;
+	double v, dv;
+
+	border(screen, arear, 1, cols[AXIS], ZP);
+	n = (Dy(arear)-4*Padding) / 10;
+	dv = (chart.ymax - chart.ymin) / 10;
+	p = addpt(arear.min, Pt(1, 2*Padding));
+	q = addpt(p, Pt(Dx(arear) - 2, 0));
+	pmax = q;
+	for(i = 0; i <= 10; i++){
+		line(screen, p, q, 0, 0, 0, cols[DIVS], ZP);
+		line(screen, addpt(q, Pt(1,0)), addpt(q, Pt(5,0)), 0, 0, 0, cols[AXIS], ZP);
+		if(i == 10) v = chart.ymin;
+		else        v = chart.ymax - i*dv;
+		snprint(buf, sizeof buf, "%f", v);
+		string(screen, addpt(q, Pt(5+Padding, -font->height/3)), cols[AXIS], ZP, afont, buf);
+		p.y += n;
+		q.y += n;
+	}
+	pmin = subpt(q, Pt(0, n));
+}
+
+void
+drawxtick(Price *price, int x)
+{
+	Point p, q;
+	char buf[12] = {0};
+	int w;
+
+	p = Pt(x, arear.min.y + 1);
+	q = Pt(x, arear.max.y - 1);
+	line(screen, p, q, 0, 0, 0, cols[DIVS], ZP);
+	line(screen, addpt(q, Pt(0,1)), addpt(q, Pt(0,5)), 0, 0, 0, cols[AXIS], ZP);
+	snprint(buf, sizeof buf, "%τ", tmfmt(&price->date, "DD/MM/YYYY"));
+	w = stringwidth(afont, buf);
+	string(screen, addpt(q, Pt(-w/2, 5+Padding)), cols[AXIS], ZP, afont, buf);
+}
+
+int
+pointy(double v)
+{
+	int y;
+	double Δv, Δp, Δy;
+
+	Δv = v - chart.ymin;
+	Δp = pmax.y - pmin.y;
+	Δy = chart.ymax - chart.ymin;
+	y = pmin.y + Δp * (Δv / Δy);
+	return y;
+}
+
+void
+redraw(void)
+{
+	Point open, high, low, close;
+	Image *c;
+	Price *price;
+	int i, x;
+
+	draw(screen, screen->r, cols[BACK], nil, ZP);
+	if(title != nil)
+		pl = string(screen, pt, cols[TEXT], ZP, font, title);
+	else
+		pl = pt;
+	drawyaxis();
+	for(i = offset; i-offset < maxprices-1 && i < chart.nprices; i++){
+		price = &chart.prices[i];
+		c = price->open < price->close ? cols[BULL] : cols[BEAR];
+		x = arear.min.x + 6*(i-offset+1) + 2;
+		if(x+4 >= arear.max.x){
+			fprint(2, "should not happen\n");
+			break;
+		}
+		open  = Pt(x, pointy(price->open));
+		high  = Pt(x, pointy(price->high));
+		low   = Pt(x, pointy(price->low));
+		close = Pt(x, pointy(price->close));
+		if(i > 0 && i%15 == 0)
+			drawxtick(price, x);
+		line(screen, high, low, 0, 0, 0, cols[LINE], ZP);
+		line(screen, open, close, 0, 0, 2, c, ZP);
+	}
+	flushimage(display, 1);
+}
+
+void
+resize(void)
+{
+	Point p, q;
+	int wmin, wmax, w;
+	char buf[32] = {0};
+
+	snprint(buf, sizeof buf, "%f", chart.ymin);
+	wmin = stringwidth(afont, buf);
+	snprint(buf, sizeof buf, "%f", chart.ymax);
+	wmax = stringwidth(afont, buf);
+	w = MAX(wmin, wmax) + Padding + Padding;
+	pt = addpt(screen->r.min, Pt(Padding, Padding));
+	p  = addpt(pt, Pt(0, font->height + Padding));
+	q  = subpt(screen->r.max, Pt(Padding, Padding + font->height + Padding));
+	chartr = Rpt(p, q);
+	arear  = chartr;
+	arear.max.x -= w;
+	maxprices = 1+(Dx(arear) - 6)/6;
+	if(maxprices >= chart.nprices)
+		offset = 0;
+	redraw();
+}
+
+Image*
+initcol(ulong c)
+{
+	Image *i;
+
+	i = allocimage(display, Rect(0, 0, 1, 1), screen->chan, 1, c);
+	if(i == nil)
+		sysfatal("allocimage: %r");
+	return i;
+}
+
+void
+initcols(void)
+{
+	cols[BACK] = initcol(0x282828ff);
+	cols[TEXT] = initcol(0xebdbb2ff);
+	cols[AXIS] = initcol(0x858891ff);
+	cols[DIVS] = initcol(0x333333ff);
+	cols[LINE] = initcol(0xa89984ff);
+	cols[BULL] = initcol(0x98971aff);
+	cols[BEAR] = initcol(0xcc241dff);
+}
+	
+
+void
+threadmain(int argc, char *argv[])
+{
+	Mouse m;
+	Rune k;
+	Alt a[] = {
+		{ nil, &m,  CHANRCV },
+		{ nil, nil, CHANRCV },
+		{ nil, &k,  CHANRCV },
+		{ nil, nil, CHANEND },
+	};
+	int n, l;
+
+	title = nil;
+	ARGBEGIN{
+	case 't':
+		title = ARGF();
+		break;
+	}ARGEND;
+	tmfmtinstall();
+	loadprices(&chart, 0);
+	if(initdraw(nil, nil, argv0) < 0)
+		sysfatal("initdraw: %r");
+	display->locking = 0;
+	if((mc = initmouse(nil, screen)) == nil)
+		sysfatal("initmouse: %r");
+	if((kc = initkeyboard(nil)) == nil)
+		sysfatal("initkeyboard: %r");
+	a[0].c = mc->c;
+	a[1].c = mc->resizec;
+	a[2].c = kc->c;
+	initcols();
+	afont = openfont(display, "/lib/font/bit/misc/unicode.6x13.font");
+	if(afont == nil)
+		sysfatal("openfont: %r");
+	offset = 0;
+	resize();
+	l = 0;
+	for(;;){
+		switch(alt(a)){
+		case 0:
+			if(ptinrect(m.xy, arear)){
+				n = ((m.xy.x - arear.min.x) / 6) - 1;
+				if(n > 0 && n < chart.nprices){
+					drawlegend(&chart.prices[n]);
+					l = 1;
+				}else if(l){
+					drawlegend(nil);
+					l = 0;
+				}
+			}else if(l){
+				drawlegend(nil);
+				l = 0;
+			}
+			break;
+		case 1:
+			if(getwindow(display, Refnone) < 0)
+				sysfatal("getwindow: %r");
+			resize();
+			break;
+		case 2:
+			switch(k){
+			case Kleft:
+				if(offset > 0 && maxprices < chart.nprices){
+					offset -= 10;
+					redraw();
+				}
+				break;
+			case Kright:
+				if(offset+maxprices < chart.nprices){
+					offset += 10;
+					redraw();
+				}
+				break;
+			case 'q':
+			case Kdel:
+				threadexitsall(nil);
+			}
+			break;
+		}
+	}
+}
+
binary files /dev/null b/candlestick.png differ
--- /dev/null
+++ b/mkfile
@@ -1,0 +1,9 @@
+</$objtype/mkfile
+
+BIN=/$objtype/bin
+TARG=candlestick
+OFILES=candlestick.$O
+HFILES=a.h
+
+</sys/src/cmd/mkone
+