#!/usr/bin/env bash
# scripts/lib/manifest.sh — the one parser for packages/*.pkgs
#
# install.sh walks desired → installed; pkg-inventory.sh walks installed → declared. Both read the
# same hand-written manifests, so both must agree on what a line MEANS: if one forgives an inline
# comment and the other does not, the same name is simultaneously "desired" and "drift", and the
# pair stops being a check on the machine. Source it — do not paste the body into a caller again
# (Refs #60: it was pasted twice, in install.sh and in pkg-inventory.sh).
#
# Contract, and tests/manifest-parser.bats is that contract:
#   name         first field of a line, emitted as one bare token — callers hand it to pacman
#   comment      `#` and everything after it is dropped, whole-line or trailing
#   CRLF         stripped (the manifests are edited on more than one box)
#   blank        empty and whitespace-only rows vanish
#   unreadable   non-zero exit, no names: a silent empty list reads as "nothing desired", and a
#                rebuild would then install nothing while reporting success
#
# Sourced, never executed; callers own `set -euo pipefail`.

read_manifest() { # $1 = manifest path; prints one package name per line
  [[ -r "$1" ]] || { printf 'read_manifest: cannot read %s\n' "$1" >&2; return 2; }
  sed 's/#.*//' "$1" | tr -d '\r' | awk '{if ($1) print $1}'
}