element_print.py

#!/usr/bin/env python3
"""Print a chemical element card on the S01 thermal printer.

Draws a random (or chosen) element as a classic periodic-table tile -- atomic
number, big symbol, name, atomic mass -- then lists its properties and a summary.
Data: Bowserinator's Periodic-Table-JSON.

Examples:
    python element_print.py                  # random element
    python element_print.py --symbol Au
    python element_print.py --number 26      # Iron
    python element_print.py --no-print
"""
from __future__ import annotations

import argparse
from pathlib import Path
import random

from PIL import Image, ImageDraw

from print_common import ROOT, Card, font, get_json

DATA = "https://raw.githubusercontent.com/Bowserinator/Periodic-Table-JSON/master/PeriodicTableJSON.json"


def draw_tile(e: dict, size: int = 180) -> Image.Image:
    img = Image.new("L", (size, size), 255)
    d = ImageDraw.Draw(img)
    d.rectangle((2, 2, size - 3, size - 3), outline=0, width=3)
    d.text((12, 8), str(e["number"]), fill=0, font=font(True, 24))
    d.text((size / 2, size * 0.46), e["symbol"], fill=0, font=font(True, 80), anchor="mm")
    d.text((size / 2, size - 44), e["name"], fill=0, font=font(False, 18), anchor="mm")
    d.text((size / 2, size - 22), f"{e['atomic_mass']:.3f}", fill=0, font=font(False, 16), anchor="mm")
    return img


def pick(elements: list[dict], args) -> dict:
    if args.symbol:
        m = next((e for e in elements if e["symbol"].lower() == args.symbol.lower()), None)
        if not m:
            raise SystemExit(f"No element with symbol {args.symbol!r}")
        return m
    if args.number:
        m = next((e for e in elements if e["number"] == args.number), None)
        if not m:
            raise SystemExit(f"No element with number {args.number}")
        return m
    return random.choice(elements)


def main() -> int:
    parser = argparse.ArgumentParser(description="Print a chemical element card on the S01 thermal printer.")
    g = parser.add_mutually_exclusive_group()
    g.add_argument("--symbol", help="Element symbol (e.g. Au).")
    g.add_argument("--number", type=int, help="Atomic number.")
    parser.add_argument("--out", type=Path, default=ROOT / "element.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("Fetching element data ...")
    elements = get_json(DATA)["elements"]
    e = pick(elements, args)
    print(f"  {e['number']} {e['symbol']} - {e['name']}")

    group = e.get("group")
    card = Card()
    card.title("ELEMENT")
    card.gap(2).image(draw_tile(e), border=False)
    card.gap(4).divider()
    card.kv("Atomic no.", str(e["number"]))
    card.kv("Mass", f"{e['atomic_mass']:.3f} u")
    card.kv("Category", e.get("category", "?"))
    card.kv("Phase (STP)", e.get("phase", "?"))
    card.kv("Period / Group", f"{e.get('period', '?')} / {group if group else '-'}")
    if e.get("electron_configuration_semantic"):
        card.kv("Config", e["electron_configuration_semantic"])
    if e.get("discovered_by"):
        card.kv("Discovered by", e["discovered_by"])
    if e.get("summary"):
        card.gap(2).divider(dashed=True).para(" ".join(e["summary"].split()), size=13, max_lines=7)
    card.footer("periodic-table-json")
    return card.finish(args.out, args.bottom_feed, args.darkness, do_print=not args.no_print)


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