#!/usr/bin/env bash
# Verifies the claims in rpmbuild-ubuntu-create-rpm.html.
#
# Two classes of check:
#   EXECUTED - run against a real upstream rpm/rpmbuild on this machine.
#              (macOS + Homebrew rpm here; the rpm is upstream, the host is not
#              Ubuntu, and every message below is reproduced verbatim.)
#   ARCHIVE  - read out of the real Ubuntu 26.04 .deb files, downloaded from
#              archive.ubuntu.com, and out of the Launchpad API.
#
# No Ubuntu or RHEL host is used. Nothing is asserted that was not produced by
# one of the two mechanisms above. Cleans up after itself.

set -u
FAILED=0
pass() { printf 'PASS  %s\n' "$1"; }
fail() { printf 'FAIL  %s\n' "$1"; FAILED=1; }
skip() { printf 'SKIP  %s\n' "$1"; }

SCRATCH="$(mktemp -d)"
trap 'rm -rf "$SCRATCH"' EXIT
cd "$SCRATCH" || exit 1

echo "== rpmbuild-ubuntu-create-rpm verification =="
echo "host      : $(uname -srm)"
echo "date      : $(date -u '+%Y-%m-%dT%H:%M:%SZ')"
if command -v rpmbuild >/dev/null 2>&1; then
  echo "rpm       : $(rpm --version)"
else
  echo "rpm       : NOT INSTALLED"
fi
echo

HAVE_RPM=0
command -v rpmbuild >/dev/null 2>&1 && command -v rpmspec >/dev/null 2>&1 && HAVE_RPM=1

# ===========================================================================
# Part 1 - ARCHIVE: what Ubuntu actually ships
# ===========================================================================
LP='https://api.launchpad.net/1.0/ubuntu/+archive/primary?ws.op=getPublishedSources&source_name=rpm&exact_match=true&status=Published&distro_series=https%3A%2F%2Fapi.launchpad.net%2F1.0%2Fubuntu%2F'

lp_version() { curl -s -m 45 "${LP}$1" | python3 -c "
import sys,json
try: d=json.load(sys.stdin)
except Exception: sys.exit(1)
e=d.get('entries') or []
print(e[0]['source_package_version'] if e else '')" 2>/dev/null; }

res=$(lp_version resolute); nob=$(lp_version noble)
if [ -n "$res" ]; then
  case "$res" in
    6.*) pass "A1a Ubuntu 26.04 (resolute) publishes rpm $res  -> major version 6" ;;
    *)   fail "A1a Ubuntu 26.04 publishes rpm $res, article claims 6.0.1-1build1" ;;
  esac
else
  skip "A1a Launchpad unreachable; cannot confirm the resolute rpm version"
fi
if [ -n "$nob" ]; then
  case "$nob" in
    4.18*) pass "A1b Ubuntu 24.04 (noble) publishes rpm $nob  -> still major version 4" ;;
    *)     fail "A1b Ubuntu 24.04 publishes rpm $nob, article claims 4.18.2+dfsg-2.1build2" ;;
  esac
else
  skip "A1b Launchpad unreachable; cannot confirm the noble rpm version"
fi

POOL='http://archive.ubuntu.com/ubuntu/pool/universe/r/rpm'
got_debs=0
if curl -sS -m 120 -o rpm.deb "$POOL/rpm_6.0.1-1build1_amd64.deb" 2>/dev/null &&
   curl -sS -m 120 -o rpmc.deb "$POOL/rpm-common_6.0.1-1build1_amd64.deb" 2>/dev/null &&
   [ -s rpm.deb ] && [ -s rpmc.deb ]; then
  mkdir -p a b && (cd a && ar x ../rpm.deb) && (cd b && ar x ../rpmc.deb) && got_debs=1
fi

if [ "$got_debs" -eq 1 ]; then
  # A2: /usr/bin/rpmbuild lives in the `rpm` package
  if tar -tf a/data.tar.* 2>/dev/null | grep -q '\./usr/bin/rpmbuild$'; then
    pass "A2  the Ubuntu 'rpm' package ships /usr/bin/rpmbuild ('apt install rpm' is right)"
  else
    fail "A2  /usr/bin/rpmbuild not found in the Ubuntu rpm package"
  fi

  mkdir -p fs && tar -xf b/data.tar.* -C fs 2>/dev/null
  M=fs/usr/lib/rpm/macros
  if [ -f "$M" ]; then
    # A3: %_topdir default
    if grep -qE '^%_topdir[[:space:]]+%\{getenv:HOME\}/rpmbuild' "$M"; then
      pass "A3  Ubuntu's shipped macros already default %_topdir to \$HOME/rpmbuild"
      grep -nE '^%_topdir' "$M" | sed 's/^/        /'
    else
      fail "A3  %_topdir default in Ubuntu's macros is not \$HOME/rpmbuild"
    fi
    # A4: %_rpmformat default is 6
    if grep -qE '^%_rpmformat[[:space:]]+6' "$M"; then
      pass "A4a Ubuntu 26.04 rpm defaults to %_rpmformat 6"
      grep -nE '^%_rpmformat|^%_binary_payload' "$M" | sed 's/^/        /'
    else
      fail "A4a %_rpmformat is not 6 in Ubuntu 26.04's macros"
    fi
    if grep -q 'zstdio' "$M"; then
      pass "A4b that format selects a zstd binary payload"
    else
      fail "A4b no zstd payload macro found"
    fi
    # A5: %dist is NOT defined
    if grep -qE '^%dist[[:space:]]' "$M"; then
      fail "A5  %dist IS defined in Ubuntu's macros -- article's claim is wrong"
    else
      pass "A5  %dist is not defined in Ubuntu's macros (only commented #%disttag etc.)"
      grep -nE '^#%dist' "$M" | sed 's/^/        /'
    fi
  else
    skip "A3-A5 rpm-common macros file not found after extraction"
  fi
else
  skip "A2-A5 Ubuntu archive unreachable; .deb-derived claims not checked"
fi
echo

# ===========================================================================
# Part 2 - EXECUTED: build the article's spec with a real rpm
# ===========================================================================
if [ "$HAVE_RPM" -eq 0 ]; then
  skip "E1-E7 no rpm/rpmbuild on this machine; build claims not executed"
  skip "      (install upstream rpm to run them: 'brew install rpm' / 'dnf install rpm-build')"
else
  T="$SCRATCH/tree"
  mkdir -p "$T"/{BUILD,RPMS,SOURCES,SPECS,SRPMS}
  mkdir -p "$T/SOURCES/helloworld-1.0"
  cat > "$T/SOURCES/helloworld-1.0/helloworld.c" <<'EOF'
#include <stdio.h>
int main(void){ printf("Hello, World!\n"); return 0; }
EOF
  (cd "$T/SOURCES" && tar -czf helloworld-1.0.tar.gz helloworld-1.0)

  # The spec EXACTLY as the old article published it (bogus date, %defattr, rm -rf).
  cat > "$T/SPECS/old.spec" <<'EOF'
Name:           helloworld
Version:        1.0
Release:        1%{?dist}
Summary:        A simple Hello World program
License:        GPL
URL:            https://example.com
Source0:        helloworld-1.0.tar.gz
BuildRequires:  gcc

%description
A basic Hello World program written in C.

%prep
%setup -q

%build
gcc -o helloworld helloworld.c

%install
rm -rf $RPM_BUILD_ROOT
install -d $RPM_BUILD_ROOT/usr/local/bin
install -m 755 helloworld $RPM_BUILD_ROOT/usr/local/bin

%files
%defattr(-,root,root,-)
/usr/local/bin/helloworld

%changelog
* Mon Feb 18 2025 MakerPM - 1.0-1
- Initial RPM release
EOF

  D="--define=_topdir $T"

  # E1: %{?dist} expands to nothing
  q=$(rpmspec "$D" -q "$T/SPECS/old.spec" 2>/dev/null | tail -1)
  case "$q" in
    helloworld-1.0-1.*)
      pass "E1  Release '1%{?dist}' resolved to plain '1' -- no dist tag: $q" ;;
    *)
      fail "E1  unexpected rpmspec -q output: $q" ;;
  esac

  # E2: rpm flags the bogus changelog weekday
  rpmspec "$D" -q "$T/SPECS/old.spec" > /dev/null 2>e2.err
  if grep -q 'bogus date in %changelog' e2.err; then
    pass "E2  rpm rejects the old article's changelog weekday"
    sed 's/^/        /' e2.err | head -2
    python3 -c "
import datetime
print('        18 Feb 2025 was a', datetime.date(2025,2,18).strftime('%A'), '-- the entry said Mon')"
  else
    fail "E2  expected a 'bogus date in %changelog' warning; got: $(cat e2.err)"
  fi

  # E3: BuildRequires cannot be satisfied - the rpm database is empty
  ndb="$SCRATCH/emptydb"; mkdir -p "$ndb"
  cnt=$(rpm --dbpath "$ndb" -qa 2>/dev/null | wc -l | tr -d ' ')
  rpmbuild "$D" -ba "$T/SPECS/old.spec" > e3.log 2>&1; rc=$?
  if [ "$rc" -ne 0 ] && grep -q 'Failed build dependencies' e3.log; then
    pass "E3  'rpmbuild -ba' fails on BuildRequires against an rpm db holding $cnt packages"
    grep -A2 'Failed build dependencies' e3.log | sed 's/^/        /'
  else
    # A host whose rpm db DOES contain gcc (e.g. Fedora) will not reproduce this.
    if [ "$cnt" -gt 0 ]; then
      skip "E3  this host's rpm database is populated ($cnt pkgs); the Debian-host"
      echo  "        failure mode cannot be reproduced here"
    else
      fail "E3  expected a BuildRequires failure; rpmbuild exit=$rc"
    fi
  fi

  # E4: --nodeps builds
  rpmbuild "$D" --define="_rpmdir $T/out-v6" --nodeps -bb "$T/SPECS/old.spec" > e4.log 2>&1; rc=$?
  f6=$(find "$T/out-v6" -name '*.rpm' 2>/dev/null | head -1)
  if [ "$rc" -eq 0 ] && [ -n "$f6" ]; then
    pass "E4a --nodeps lets the same spec build to completion"
    echo "        -> $(basename "$f6")"
  else
    fail "E4a --nodeps build failed (exit=$rc); tail: $(tail -3 e4.log | tr '\n' ' ')"
  fi
  # E4b: BUILDROOT is created automatically inside a per-package build dir
  if grep -q 'BUILD/helloworld-1.0-build/BUILDROOT' e4.log; then
    pass "E4b rpm created BUILD/helloworld-1.0-build/BUILDROOT itself (no need to mkdir it)"
  else
    skip "E4b per-package BUILDROOT path not seen in this rpm version's log"
  fi

  # E5: default format declares rpmlib(PayloadIsZstd)
  if [ -n "$f6" ]; then
    r6=$(rpm -qp --requires "$f6" 2>/dev/null | grep rpmlib | sort | tr '\n' ';')
    p6=$(rpm -qp --qf '%{PAYLOADCOMPRESSOR}' "$f6" 2>/dev/null)
    if printf '%s' "$r6" | grep -q 'PayloadIsZstd'; then
      pass "E5  default build (format $(rpm --eval '%_rpmformat')) payload=$p6 and requires rpmlib(PayloadIsZstd)"
      rpm -qp --requires "$f6" 2>/dev/null | grep rpmlib | sed 's/^/        /'
    else
      skip "E5  this rpm's default format does not emit a zstd payload; requires: $r6"
    fi
  fi

  # E6: --define '_rpmformat 4' drops the modern rpmlib requirement
  rpmbuild "$D" --define="_rpmdir $T/out-v4" --define="_rpmformat 4" --nodeps \
           -bb "$T/SPECS/old.spec" > e6.log 2>&1
  f4=$(find "$T/out-v4" -name '*.rpm' 2>/dev/null | head -1)
  if [ -n "$f4" ]; then
    r4=$(rpm -qp --requires "$f4" 2>/dev/null | grep rpmlib | sort | tr '\n' ';')
    p4=$(rpm -qp --qf '%{PAYLOADCOMPRESSOR}' "$f4" 2>/dev/null)
    if printf '%s' "$r4" | grep -q 'PayloadIsZstd'; then
      fail "E6  _rpmformat 4 still requires rpmlib(PayloadIsZstd): $r4"
    else
      pass "E6  --define '_rpmformat 4' -> payload=$p4, no rpmlib(PayloadIsZstd)"
      rpm -qp --requires "$f4" 2>/dev/null | grep rpmlib | sed 's/^/        /'
    fi
  else
    fail "E6  the _rpmformat 4 build produced no package"
  fi

  # E7: %_topdir default at runtime
  td=$(rpm --eval '%_topdir')
  case "$td" in
    */rpmbuild) pass "E7  rpm --eval '%_topdir' = $td (the .rpmmacros step is redundant)" ;;
    *)          fail "E7  unexpected %_topdir: $td" ;;
  esac
fi
echo

# ===========================================================================
# Explicit non-claims
# ===========================================================================
skip "N1  'an rpm lacking PayloadIsZstd refuses the package' -- rpmlib() deps are"
echo "        satisfied by the installing rpm binary; the REQUIREMENT is measured above,"
echo "        the refusal is documented rpm behaviour and was NOT reproduced (no old rpm here)."
skip "N2  'a binary linked on Ubuntu gets glibc Requires RHEL cannot meet' -- documented"
echo "        behaviour of rpm's automatic dependency generator; NOT reproduced (no Linux host)."
skip "N3  nothing here ran on Ubuntu. The build used upstream rpm on $(uname -s)."
echo

if [ "$FAILED" -eq 0 ]; then
  echo "RESULT: no FAILures."
  exit 0
else
  echo "RESULT: at least one FAILure above."
  exit 1
fi