quartz-research-note/add_timestamp.sh

#!/bin/bash
cwd=`dirname "${0}"`

function rewritedate () {
	echo "$1 : $2"
	echo $2 | xargs -I{} yq -i --front-matter="process" '.date="{}"' "$1"
}
FILES=$(find $cwd/content -name "*.md")
IFS=$'\n'
for f in $FILES
do
BDATE=$(stat -f "%SB" "$f");
DATE=$(LC_ALL=C date -j -f "%b %d %H:%M:%S %Y" "$BDATE" "+%FT%T%z");
FLINE=$(head -n 1 "$f");

LOCALDATE=$(LC_ALL=C date -j -f "%b %d %H:%M:%S %Y" "$BDATE" "+%s"  );
GITDATERAW=$(git blame $f |tail -1| grep -Eo '\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}');
GITDATE=$(LC_ALL=C date -j -f "%Y-%m-%d %H:%M:%S" "$GITDATERAW" "+%s");
GITDATE_2=$(LC_ALL=C date -j  -f "%Y-%m-%d %H:%M:%S" "$GITDATERAW" "+%FT%T%z");
if [[ "$FLINE" == "---" ]];
then
ORIGINDATE_RAW=$(yq --front-matter=extract '.date' "$f")
ORIGINDATE=$(date -j -f "%FT%T%z" "$ORIGINDATE_RAW" "+%s")

if [ $LOCALDATE -lt $ORIGINDATE ]; then 
    echo "$f has frontmatter and date of local file is older. overwriting."
    rewritedate $f $DATE
fi

if [ $GITDATE -lt $LOCALDATE ]; then
    echo "Oldest commit date is older than birth date. overwriting"
    rewritedate $f $GITDATE_2
fi
else
echo "$f has no frontmatter, adding to it";
gsed -i '1i---\n---' "$f"
rewritedate $f $DATE
fi
done