#!/bin/sh -e

. ./config

writings_by_cat() {
    for file in "$DIR_WRITINGS"/*."$EXT_WRITINGS"; do
        case "$(sed -n '2p' "$file") " in
            *" $1 "*) echo "$file" ;;
        esac
    done
}

if [ -z "$1" ]; then
  cats="$(categories "$DIR_WRITINGS"/*."$EXT_WRITINGS")"
  writings="$DIR_WRITINGS/*.$EXT_WRITINGS"
  all=1
else
  cats="$1"
  writings="$(writings_by_cat "$1")"
fi

writings=$(for f in $writings; do
    date="$(date -d "$(sed -n '3s/^; //p' "$f")" "+%s")"
    printf '%s %s\n' "$date" "$f"
done | sort -rn | cut -f2 -d' ')

cat <<EOF
<nav class="categories">
$([ -z "$all" ] && echo "#<a class=\"category\" href=\"/writings/\">all</a>")
$(for c in $cats; do echo "#<a class=\"category\" href=\"/writings/$c\">$c</a>"; done)
</nav>
<ul class="writ-index">
EOF

for f in $writings; do
  title=$(sed -n '1s/^; //p' "$f")
  cats=$(sed -n '2s/^; //p' "$f")
  date="$(date -d "$(sed -n '3s/^; //p' "$f")" "+%d %b %Y")"
  file="$(basename "$f" .md)"

  cat_links=$(echo "$cats" | tr ' ' '\n' | while read -r cat; do
    echo "#<a class=\"category\" href=\"/writings/$cat\">$cat</a>"
  done | tr '\n' ' ')

  cat <<EOF
<li class="writing">
<span>$date&nbsp; <a href="/writings/$file">$title</a></span>
<span>$cat_links</span>
</li>
EOF
done

echo "</ul>"