#
# This script is a conveter helper for Obsiditan linter
# to converter the orginal date field name
# from "date created" to "date-created"
# from "date modified" to "date-modified"
# because the dataview plugin cannot identify the white space
#
# Created on: 2022-07-10
# Author: Xing@deyisi.com

import os
import argparse


def go_through_docs(work_dir):
    count = 0
    for root, dirs, files in os.walk(work_dir):
        for filename in files:
            if filename.endswith(".md"):
                if convert(os.path.join(root, filename)):
                    count += 1
                    print(f"{count:3d}: \"{filename}\" is converted")


def change(line):
    if line.startswith("date created:"):
        return line.replace(
            "date created",
            "date-created"
        )
        converted = True
    if line.startswith("date modified:"):
        return line.replace(
            "date modified",
            "date-modified"
        )
    if line.startswith("date updated:"):
        return line.replace(
            "date updated",
            "date-updated"
        )


def convert(filename):
    contents = []
    converted = False
    with open(filename, encoding="utf-8") as reader:
        yaml_entry = False
        line_no = 0
        for line in reader.readlines():
            if line_no == 0:
                if line == "---\n":
                    yaml_entry = True

            if yaml_entry:
                if line == "---\n" and line_no > 0:
                    yaml_entry = False
                else:
                    updated = change(line)
                    if updated is not None:
                        line = updated
                        converted = True

            contents.append(line)

            line_no += 1

        with open(filename, "w", encoding="utf-8") as writer:
            writer.write("".join(contents))
        return converted


if __name__ == "__main__":
    parser = argparse.ArgumentParser(
        description="Converter existing Markdown documents with"
        " new linter format.\n"
        "The linter format `date created` will change to "
        "`date-created` format.",
    )

    parser.add_argument(
        '--dir',
        help='The location of the source ',
        default=os.getcwd(),
    )
    args = parser.parse_args()
    work_dir = args.dir

    print(f"Converting `{work_dir}` to new format...")

    if work_dir is None:
        work_dir = os.getcwd()

    if os.path.isdir(work_dir):
        go_through_docs(work_dir)
    else:
        print(f"Error: no such directory {work_dir} found.")