Improved formatting for WikiTree GEDCOMpare output

gedcom_formatter.py

# Instructions:
# 1. Import a gedcom file into wikitree.com
# 2. When adding new profile from the gedcom, copy the intended output into a file called 'input.txt' that is in the same directory as this script.
# 3. Run this script. It will continuously watch for changes to the 'input.txt' file and format the contents.
#
import os
import sys
import time
from datetime import datetime

INPUT_FILE  = 'input.txt'
OUTPUT_FILE = 'input.txt' # output to the same file

def readfile():
    with open(INPUT_FILE, "r") as f:
        content = f.read().splitlines()
        f.close()
    # add a trailing newline. All text files should end 
    # with a newline on its own line, but it's not clear that the input here honors that.
    content.append("\n")
    return content

# Adds a newline before any lines starting with '''
# These indicate section headers, like:
#   '''Residences'''
# or
#   '''Born'''
def prepend_section_newlines(lines):
    for i in range(len(lines)):
        if lines[i].startswith("'''"):
            lines[i] = "\n" + lines[i]
    return lines

# Formats the "Files" listing from something like:
#   File: {{Ancestry Tree Media|1234|abc-def-ghi}} 
#   Format: jpg. 
#   name1, name2, name3. 
# to:
#   * File: {{Ancestry Tree Media|1234|abc-def-ghi}} Format: jpg. name1, name2, name3.
#
# This makes all of the content formatted nicely with bullet points.
def format_files_listing(lines):
    output = []
    i = 0
    while i < len(lines): # use while since we manipulate value of i
        if lines[i].startswith("File: {{Ancestry"):
            if i + 2 >= len(lines):
                break
            output.append("* " + lines[i] + " " + lines[i+1] + " " + lines[i+2])
            i += 2
        else:
            output.append(lines[i])
        i += 1
    return output

def writefile(content):
    with open(OUTPUT_FILE, "w") as f:
        f.write(content)
        f.close()

def wait_for_file_modification():
    lastModifiedSeconds = os.path.getmtime(INPUT_FILE)
    while lastModifiedSeconds == os.path.getmtime(INPUT_FILE):
        time.sleep(1)

def main():
    # Force stdout to flush the buffer so messages appear more quickly.
	# Without this, sometimes a `print` call will not actually show the output immediately.
    sys.stdout = os.fdopen(sys.stdout.fileno(), 'w', 0)

    # Infinitely loop, waiting for modifications to the file and formatting the file content whenever there's a change.
    while True:
        print('Formatting ' + INPUT_FILE + ' ...')
        lines = readfile()
        lines = prepend_section_newlines(lines)
        lines = format_files_listing(lines)
        # print(lines) # DEBUG
        print('Writing formatted content to ' + INPUT_FILE)
        writefile("\n".join(lines))
        print('Waiting for modification of ' + INPUT_FILE)
        wait_for_file_modification()

if __name__ == '__main__':
    main()