hatena_md_converter.py

import argparse
import os
import re
import sys

import pyperclip

BraKetDefinition = r"""
[tex:
\def\bra#1{\mathinner{\left\langle{#1}\right|}}
\def\ket#1{\mathinner{\left|{#1}\right\rangle}}
\def\braket#1#2{\mathinner{\left\langle{#1}\middle|#2\right\rangle}}
]
"""


def app():
    parser = argparse.ArgumentParser()
    parser.add_argument("-p", "--path", help="Markdown file path. If empty, the text on clipboard is used.")
    parser.add_argument("-d", "--dump", action="store_true", help="Dump converted result.")
    parser.add_argument("-bk", "--braket", action="store_true", help="Add bra ket definition.")
    args = parser.parse_args()

    if args.path is None:
        md_text = pyperclip.paste()
    else:
        if os.path.exists(args.path):
            with open(args.path) as f:
                md_text = f.read()
        else:
            print("No such markdown file.")
            return 2

    display_math = "<div align=\"center\">\n[tex:\\begin{{aligned}}\n{}\n\\end{{aligned}}]\n</div>"
    for m in re.findall(r"(\$\$\n(.+?)\n\$\$)", md_text, flags=(re.MULTILINE | re.DOTALL)):
        dm = m[1].replace("[", r"\[").replace("]", r"\]")
        md_text = md_text.replace(m[0], display_math.format(dm))

    inline_math = "[tex: {} ]"
    for m in re.findall(r"(\$(.+?)\$)", md_text, flags=(re.MULTILINE | re.DOTALL)):
        im = m[1].replace("_", " _ ").replace("^", " ^ ").replace("[", r"\\[").replace("]", r"\\]")
        md_text = md_text.replace(m[0], inline_math.format(im))

    if args.braket:
        md_text = BraKetDefinition + md_text
        
    pyperclip.copy(md_text)

    if args.dump:
        print(md_text)

    return 0


if __name__ == "__main__":
    res = app()
    sys.exit(res)