#!/bin/bash
#
# trash — move files to the Trash following the FreeDesktop.org Trash Spec 1.0.
#
# Chooses the correct trash directory regardless of distro / desktop:
#   * Items on the same filesystem as $HOME go to the "home trash":
#       ${XDG_DATA_HOME:-$HOME/.local/share}/Trash
#   * Items on a different filesystem go to a top-dir trash on that mount:
#       <mount>/.Trash/$uid  (if it is a valid, sticky, non-symlink dir)
#       <mount>/.Trash-$uid  (fallback, always valid to create)
#
# Also writes the matching .trashinfo metadata so file managers actually
# display and can restore the trashed items.

trash() {
  local uid=$UID
  local home_trash="${XDG_DATA_HOME:-$HOME/.local/share}/Trash"
  local home_top
  home_top=$(df --output=target -- "$HOME" 2>/dev/null | tail -n 1)

  local item abs top trash_dir files_dir info_dir base stem ext candidate n
  local deletion_date info_path

  for item in "$@"; do
    if [ ! -e "$item" ] && [ ! -L "$item" ]; then
      echo "Error: '$item' does not exist." >&2
      continue
    fi

    # Resolve to an absolute path for the .trashinfo Path field.
    abs=$(readlink -f -- "$item") || abs=$item

    # Decide which trash to use based on the filesystem the item lives on.
    top=$(df --output=target -- "$item" 2>/dev/null | tail -n 1)
    if [ -z "$top" ] || [ "$top" = "$home_top" ]; then
      trash_dir=$home_trash
    else
      if [ -d "$top/.Trash" ] && [ ! -L "$top/.Trash" ] &&
         [ "$(( $(stat -c %a -- "$top/.Trash" 2>/dev/null || echo 0) & 3777 ))" -eq 1777 ]; then
        trash_dir="$top/.Trash/$uid"
      else
        trash_dir="$top/.Trash-$uid"
      fi
      # If we can't create a top-dir trash on this mount (e.g. read-only /
      # root or restricted top dir), fall back to the home trash, which is
      # always writable. This matches what GVFS does.
      if ! mkdir -p -- "$trash_dir/files" "$trash_dir/info" 2>/dev/null; then
        trash_dir=$home_trash
      fi
    fi

    files_dir=$trash_dir/files
    info_dir=$trash_dir/info
    if ! mkdir -p -- "$files_dir" "$info_dir"; then
      echo "Error: cannot create trash dir '$trash_dir' for '$item'." >&2
      continue
    fi

    # Pick a unique name, preserving the extension (and handling none).
    base=$(basename -- "$item")
    if [[ $base == *.* ]]; then
      stem=${base%.*}
      ext=.${base##*.}
    else
      stem=$base
      ext=
    fi

    candidate=$base
    n=1
    while [ -e "$files_dir/$candidate" ] || [ -e "$info_dir/$candidate.trashinfo" ]; do
      candidate=${stem}_$n$ext
      n=$((n + 1))
    done

    # Write the .trashinfo first; if mv fails, remove it to stay consistent.
    deletion_date=$(date +%Y-%m-%dT%H:%M:%S)
    info_path=$info_dir/$candidate.trashinfo
    {
      printf '[Trash Info]\n'
      printf 'Path=%s\n' "$abs"
      printf 'DeletionDate=%s\n' "$deletion_date"
    } > "$info_path"

    if mv -f -- "$item" "$files_dir/$candidate"; then
      echo "Moved '$item' to '$files_dir/$candidate'"
    else
      echo "Error: failed to move '$item'." >&2
      rm -f -- "$info_path"
    fi
  done
}

trash "$@"