daylight_print.py

#!/usr/bin/env python3
"""Print today's daylight (sunrise/sunset) on the S01 thermal printer.

Pulls sun times for a location from sunrise-sunset.org, draws the sun's arc
across the sky with the current position marked, and lists first light, sunrise,
solar noon, sunset, last light, and day length. Times are shown in your local
timezone.

Examples:
    python daylight_print.py                       # default location
    python daylight_print.py --lat 40.71 --lng -74.0 --place "New York"
    python daylight_print.py --no-print
"""
from __future__ import annotations

import argparse
from datetime import datetime, timezone
from math import cos, pi, radians, sin
from pathlib import Path

from PIL import Image, ImageDraw

from print_common import ROOT, Card, font, get_json

API = "https://api.sunrise-sunset.org/json?lat={lat}&lng={lng}&formatted=0"


def local(iso: str) -> datetime:
    return datetime.fromisoformat(iso).astimezone()


def draw_arc(sunrise: datetime, sunset: datetime, now: datetime, w: int, h: int = 150) -> Image.Image:
    img = Image.new("L", (w, h), 255)
    d = ImageDraw.Draw(img)
    margin = 30
    horizon = h - 22
    arc_h = horizon - 14
    steps = 120
    pts = [(margin + t / steps * (w - 2 * margin), horizon - sin(pi * t / steps) * arc_h)
           for t in range(steps + 1)]
    d.line(pts, fill=0, width=2)
    d.line((0, horizon, w, horizon), fill=0, width=1)

    # endpoint ticks + labels
    tiny = font(False, 11)
    d.line((margin, horizon - 5, margin, horizon + 5), fill=0, width=2)
    d.line((w - margin, horizon - 5, w - margin, horizon + 5), fill=0, width=2)
    d.text((margin, horizon + 6), "rise", fill=0, font=tiny, anchor="ma")
    d.text((w - margin, horizon + 6), "set", fill=0, font=tiny, anchor="ma")

    # current sun position along the arc
    span = (sunset - sunrise).total_seconds()
    f = (now - sunrise).total_seconds() / span if span else 0
    night = f < 0 or f > 1
    f = min(1.0, max(0.0, f))
    sx = margin + f * (w - 2 * margin)
    sy = horizon - sin(pi * f) * arc_h
    r = 7
    if night:
        d.ellipse((sx - r, sy - r, sx + r, sy + r), outline=0, width=2)  # hollow = below horizon
    else:
        d.ellipse((sx - r, sy - r, sx + r, sy + r), fill=0)
        for ang in range(0, 360, 45):
            dx, dy = cos(radians(ang)), sin(radians(ang))
            d.line((sx + dx * (r + 2), sy + dy * (r + 2), sx + dx * (r + 6), sy + dy * (r + 6)), fill=0, width=1)
    return img


def main() -> int:
    parser = argparse.ArgumentParser(description="Print today's daylight on the S01 thermal printer.")
    parser.add_argument("--lat", type=float, default=40.7128, help="Latitude (default: New York).")
    parser.add_argument("--lng", type=float, default=-74.0060, help="Longitude (default: New York).")
    parser.add_argument("--place", default="New York", help="Place label for the header.")
    parser.add_argument("--out", type=Path, default=ROOT / "daylight.png")
    parser.add_argument("--darkness", type=int, choices=range(1, 6), default=3)
    parser.add_argument("--bottom-feed", type=int, default=24)
    parser.add_argument("--no-print", action="store_true")
    args = parser.parse_args()

    print(f"Fetching sun times for {args.place} ...")
    res = get_json(API.format(lat=args.lat, lng=args.lng))["results"]
    sunrise, sunset = local(res["sunrise"]), local(res["sunset"])
    secs = int(res["day_length"])
    day_len = f"{secs // 3600}h {secs % 3600 // 60}m"
    now = datetime.now(timezone.utc).astimezone()
    print(f"  sunrise {sunrise:%H:%M}  sunset {sunset:%H:%M}  ({day_len})")

    card = Card()
    card.title("DAYLIGHT")
    card.heading(f"{args.place}  -  {sunrise:%b %d}", size=15)
    card.gap(4).image(draw_arc(sunrise, sunset, now, card.inner_w), border=True)
    card.gap(2).divider()
    card.kv("First light", f"{local(res['civil_twilight_begin']):%H:%M}")
    card.kv("Sunrise", f"{sunrise:%H:%M}")
    card.kv("Solar noon", f"{local(res['solar_noon']):%H:%M}")
    card.kv("Sunset", f"{sunset:%H:%M}")
    card.kv("Last light", f"{local(res['civil_twilight_end']):%H:%M}")
    card.kv("Day length", day_len)
    card.footer("sunrise-sunset.org", now.strftime("%Y-%m-%d %H:%M"))
    return card.finish(args.out, args.bottom_feed, args.darkness, do_print=not args.no_print)


if __name__ == "__main__":
    raise SystemExit(main())