figlist

#!/bin/bash

dep_hint() {
  case "$1" in
    pdftotext|pdftoppm) echo "  sudo apt install poppler-utils   # Debian/Ubuntu"
                        echo "  sudo dnf install poppler-utils   # Fedora"
                        echo "  brew install poppler              # macOS" ;;
    fzf)                echo "  sudo apt install fzf              # Debian/Ubuntu"
                        echo "  brew install fzf                  # macOS"
                        echo "  https://github.com/junegunn/fzf" ;;
    chafa)              echo "  sudo apt install chafa            # Debian/Ubuntu"
                        echo "  brew install chafa                # macOS"
                        echo "  https://hpjansson.org/chafa/" ;;
    zathura)            echo "  sudo apt install zathura          # Debian/Ubuntu"
                        echo "  brew install zathura              # macOS (via homebrew-cask)" ;;
  esac
}

require() {
  if ! command -v "$1" &>/dev/null; then
    echo "Error: '$1' not found."
    dep_hint "$1"
    exit 1
  fi
}

if [[ $# -eq 0 ]]; then
  echo "Usage: $0 <file.pdf> [pattern]"
  exit 1
fi

pdf="$1"
pattern="${2:-^Figure [0-9]+-[0-9]+.[[:space:]][[:alpha:]]}"

if [[ ! -f "$pdf" ]]; then
  echo "Error: file '$pdf' not found"
  exit 1
fi

require pdftotext
require pdftoppm
require fzf
require chafa
# zathura: not checked — enter bind silently does nothing if absent

pdftotext "$pdf" - \
  | sed 's/\f/\n---PAGE---\n/g' \
  | awk -v pat="$pattern" '
      /^---PAGE---$/ { page++; next }
      $0 ~ pat      { print page+1 "\t" $0 }
    ' \
  | fzf \
      --no-sort \
      --delimiter='\t' \
      --with-nth=2 \
      --preview='
        pdf="'"$pdf"'"
        page={1}
        cols=$FZF_PREVIEW_COLUMNS
        lines=$FZF_PREVIEW_LINES
        pdf_name=$(basename "$pdf" .pdf)
        mkdir -p /tmp/pdfpage
        tmpimg=$(mktemp "/tmp/pdfpage/${pdf_name}_XXXX")
        pdftoppm -f "$page" -l "$page" -rx 450 -ry 250 -cropbox -jpeg -singlefile "$pdf" "$tmpimg"
        chafa -f sixels --size="${cols}x${lines}" "${tmpimg}.jpg"
        rm -f "${tmpimg}.jpg" "$tmpimg"
      ' \
      --preview-window=right:70% \
      --bind 'ctrl-r:change-preview-window(hidden|70%)' \
      --bind 'enter:execute(zathura --page={1} "'"$pdf"'")' \
      --bind 'ctrl-s:toggle-sort'