#!/bin/sh -eu

cache=$HOME/.cache/fzf-doc
documentation=/etc/documentation

fzf_doc_preview() {
  file=$1
  extension=${file##*.}
  case "$extension" in
    md) mdcat -l "$file" ;;
    html) w3m -dump "$file" ;;
    pdf) pdftotext "$file" - ;;
    *) grep -hi -B 10 -A 10 . "${file}" ;;
  esac
}

if [ ! -f "$cache" ] || test "$cache" -ot "$documentation"; then
  grep -lRi \
  --include=*.md \
  --include=*.txt \
  --include=*.pdf \
  --include=*.html \
  --include=*.yml \
  --include=*.yaml \
  . /etc/documentation > "$cache";
fi

[ "${1-}" = "--preview" ] && fzf_doc_preview "${2-}" && exit;

grep -i "${1-.}" "$cache" \
  | fzf --preview "fzf-doc --preview {}" \
  | while read -r file

do
  extension=${file##*.}
  case "$extension" in
    md) mdcat -cl "$file" | vim - ;;
    html) w3m -dump "$file" | vim - ;;
    pdf) pdftotext "$file" - | vim - ;;
    yml) vim "$file" ;;
    yaml) vim "$file" ;;
    *) vim "$file" ;;
  esac
done