start

#!/usr/bin/env python3

import argparse
from pathlib import Path

from misc.date_utils import current_puzzle_year, next_day

PARSER = argparse.ArgumentParser(
    prog="./start", description="Scaffold a new Advent of Code solution"
)
PARSER.add_argument(
    "day",
    type=int,
    help=(
        "Which puzzle day to start, between [1,25]."
        " Defaults to the next day without a folder (matching `day_N`) in that year."
    ),
    nargs="?",
)
PARSER.add_argument("--year", default=current_puzzle_year(), help="Puzzle year")

if __name__ == "__main__":
    ARGS = PARSER.parse_args()

    year_dir = Path("solutions", ARGS.year)
    year_dir.mkdir(parents=True, exist_ok=True)

    if ARGS.day is None:
        day = next_day(year_dir) + 1
    else:
        day = ARGS.day

    if not 1 <= day <= 25:
        PARSER.error(f"day {day} is not in range [1,25]")

    day_dir = Path(year_dir, f"day_{day:02}")

    day_dir.mkdir(parents=True, exist_ok=True)
    Path(day_dir, "input.txt").touch()
    Path(day_dir, "input.test.txt").touch()

    notes_path = Path(day_dir, "README.md")
    if not notes_path.exists():
        notes_path.write_text(
            "\n\n".join(
                [
                    f"# Day {day} ({ARGS.year})",
                    f"`TITLE` ([prompt](https://adventofcode.com/{ARGS.year}/day/{day}))",
                    "Use this space for notes on the day's solution and to document what you've learned!",
                    "## Part 1",
                    "## Part 2",
                    "",
                ]
            )
        )

    solution_path = Path(day_dir, "solution.py")
    if solution_path.exists():
        # if we're here, it's probably a re-run
        print("ensuring input files exist")
        print("skipping solution creation, file already exists")
    else:
        template = Path("misc/example_solution.py.tmpl").read_text()
        replaced_template = template.replace("<YEAR>", ARGS.year).replace(
            "<DAY>", str(day)
        )
        solution_path.write_text(replaced_template)
        print("Created a new Solution file at", solution_path)