#!/usr/bin/env bash
# Build the punktfunk-host RPM from the committed tree, for the Gitea RPM registry (Bazzite).
#
# Counterpart to ../debian/build-deb.sh. The library Requires (libavcodec.so.NN, …) are
# auto-generated by rpmbuild from the binary it links — so build this in the Fedora 43 image
# (ci/fedora-rpm.Dockerfile) to match Bazzite's sonames. libcuda is excluded in the spec.
#
# Usage: PF_VERSION=0.0.1 [PF_RELEASE=0.ci42.gdeadbee] bash packaging/rpm/build-rpm.sh
# Output: dist/punktfunk-<version>-<release>.<arch>.rpm  (+ the -debuginfo/-debugsource subpkgs)
set -euo pipefail

PF_VERSION="${PF_VERSION:-0.3.0}"   # canary base; keep one minor ahead of the latest stable release
PF_RELEASE="${PF_RELEASE:-1}"
# PF_WITH_WEB=1 builds the punktfunk-web subpackage too (needs `bun` on PATH — present in the CI
# builder image, not in a plain mock chroot). Default off so a bare `rpmbuild`/COPR still works.
WEB_OPT=()
[ "${PF_WITH_WEB:-0}" = "1" ] && WEB_OPT=(--with web)
ROOTDIR="$(cd "$(dirname "$0")/../.." && pwd)"
cd "$ROOTDIR"

TOP="$(mktemp -d)"
trap 'rm -rf "$TOP"' EXIT
mkdir -p "$TOP"/{SOURCES,SPECS,BUILD,BUILDROOT,RPMS,SRPMS}

# Source tarball with the prefix %autosetup expects (punktfunk-<version>/). From HEAD so the
# build is reproducible from a commit (CI checks one out); the spec is read from the working
# tree directly, so spec edits apply without a re-commit.
git archive --format=tar.gz --prefix="punktfunk-${PF_VERSION}/" \
  -o "$TOP/SOURCES/punktfunk-${PF_VERSION}.tar.gz" HEAD

# libcuda link stub (self-maintaining). The zerocopy FFI links the NVIDIA driver lib (-lcuda), but
# the CI builder has no GPU and never RUNS CUDA. Synthesize a stub libcuda that DEFINES every cu*
# driver symbol the host source references, derived from the source HERE so a newly-added cu* call
# can't silently break the link. (ci/fedora-rpm.Dockerfile ships a frozen list that went stale —
# undefined cuStreamCreateWithPriority/cuMemcpy2DAsync_v2/…; this regen supersedes it.) Defining
# extra unused symbols is harmless; a missing one fails the link. Only when /usr/lib64 is writable
# (CI image runs as root) — COPR/mock provides the real cuda-cudart-devel stub instead.
if [ "$(id -u)" = 0 ] && [ -d /usr/lib64 ]; then
  CU_SYMS="$(grep -rhoE '\bcu[A-Z][A-Za-z0-9_]*' crates/punktfunk-host/src/ | sort -u || true)"
  if [ -n "$CU_SYMS" ]; then
    STUB_C="$(mktemp --suffix=.c)"
    for s in $CU_SYMS; do printf 'int %s(void){return 0;}\n' "$s" >> "$STUB_C"; done
    gcc -shared -fPIC -Wl,-soname,libcuda.so.1 -o /usr/lib64/libcuda.so.1 "$STUB_C"
    ln -sf libcuda.so.1 /usr/lib64/libcuda.so
    rm -f "$STUB_C"; ldconfig 2>/dev/null || true
    echo "== libcuda stub regenerated from source: $(printf '%s\n' "$CU_SYMS" | wc -l) symbols =="
  fi
fi

# --nodeps: the spec's BuildRequires (cargo, rust, *-devel) are for COPR's mock chroot, which
# resolves them from RPMs. Our builder image provides the toolchain via rustup (so
# rust-toolchain.toml's pinned channel works) and the -devel libs via dnf, neither of which
# rpmbuild's RPM-level check sees — skip it; a genuinely missing dep fails the compile/link.
rpmbuild -bb --nodeps "${WEB_OPT[@]}" \
  --define "_topdir $TOP" \
  --define "pf_version ${PF_VERSION}" \
  --define "pf_release ${PF_RELEASE}" \
  packaging/rpm/punktfunk.spec

mkdir -p dist
find "$TOP/RPMS" -name '*.rpm' -exec cp -v {} dist/ \;
echo "== Requires (must NOT contain libcuda) =="
rpm -qp --requires dist/punktfunk-${PF_VERSION}-*.rpm 2>/dev/null | grep -iE 'cuda|nvidia' \
  && echo "  !! NVIDIA/CUDA leak !!" || echo "  clean"