. "$BST_LIB"

# lame 3.100 (poky recipes-multimedia/lame) -- the LAME MP3 encoder.
#
# THE GATE IS A BYTE-FOR-BYTE COMPARISON AGAINST A REFERENCE ENCODE, which is
# the ticket's own criterion and a much stronger statement than "it produced an
# MP3". data/lame-ref-128cbr.mp3 was produced by lame 3.100 -- the identical
# release, from the identical tarball this recipe builds -- encoding the
# identical fixture at the identical settings, on an x86-64 host. If the wasm32
# build agrees with it byte for byte, then this arm's floating-point
# psychoacoustic model, its MDCT, its quantisation loop and its bitstream
# formatter all reproduce the reference implementation exactly. Nothing about
# that is implied by the encoder merely running.
#
# WHY A LOSSY CODEC CAN BE TESTED THIS HARD AT ALL. flac (57-flac.test) is
# checkable because losslessness is an exact property. lame is not lossless, so
# the analogous round-trip assertion does not exist -- decode(encode(x)) != x by
# construction, and how far it differs is a matter of psychoacoustics rather than
# arithmetic. What replaces it is DETERMINISM: for a fixed encoder version, fixed
# settings and fixed input, the output is one specific byte string, so a
# reference encode is a complete oracle. That is why the comparison is against a
# stored artifact rather than against a property.
#
# WHAT A RED HERE WOULD AND WOULD NOT MEAN. A mismatch is NOT automatically a
# brintOS defect: lame's psymodel runs on doubles and calls libm (log, exp, pow,
# sin), and libm is not correctly rounded, so a last-ulp difference between this
# arm's libm and the host's could in principle propagate through the
# quantisation decisions into different bits. That is why the mismatch case
# reports the size and digest it actually got instead of only failing: a
# same-size, different-digest result is the libm story, and a wildly different
# size is a real encoder fault. The fixture itself is digest-checked first
# (lame/fixture-digest), so a byte difference can never be blamed on the encoder
# when the shell in fact wrote a different WAV.
#
# WHAT RUNS ON TARGET IS THE PORTABLE C. configure answered `working SSE
# intrinsics... no` and `if I have to build the internal vector lib... no`, and
# the recipe passes no --enable-nasm, so no assembly and no x86 intrinsic is
# compiled in. A green below is a statement about this arm's own arithmetic.
#
# THE FIXTURE IS BUILT WITHOUT FORKING -- every byte of the 32 KiB sawtooth comes
# from shell arithmetic and the printf builtin, for the reason 57-flac.test
# states: on this arm each exec is a fresh wasm module instantiation.

require lame lame/present

tmp=${TMPDIR:-/tmp}/bst-lame.$$
mkdir -p "$tmp" 2>/dev/null
pcm=$tmp/tone.pcm
wav=$tmp/tone.wav
mp3=$tmp/tone.mp3
ref=$BST_DATA/lame-ref-128cbr.mp3

# ------------------------------------------------------------------ fixture ---
# The same 256-sample sawtooth 57-flac.test uses -- 16-bit signed little-endian
# mono, repeated 64 times: 16384 samples, 32768 bytes. Wrapped here in a
# canonical 44-byte RIFF/WAVE header at 44100 Hz, because 44100 is an MPEG-1
# Layer III rate and the ticket asks for a WAV at a fixed bitrate; at 8 kHz lame
# would drop to MPEG-2.5, where 128 kbps does not exist.
i=0; esc=""
while [ $i -lt 256 ]; do
  esc="$esc\\000\\$((i/64))$((i/8%8))$((i%8))"
  i=$((i+1))
done
j=0
while [ $j -lt 64 ]; do printf "$esc"; j=$((j+1)); done > "$pcm"

ob()   { printf "\\$(($1%256/64))$(($1%256/8%8))$(($1%8))"; }
le16() { ob $1; ob $(($1/256)); }
le32() { ob $1; ob $(($1/256)); ob $(($1/65536)); ob $(($1/16777216)); }
{ printf 'RIFF'; le32 32804; printf 'WAVEfmt '; le32 16; le16 1; le16 1;
  le32 44100; le32 88200; le16 2; le16 16; printf 'data'; le32 32768; cat "$pcm"; } > "$wav"

wavbytes=$(wc -c < "$wav" 2>/dev/null | tr -d ' ')
check_eq lame/fixture-size 32812 "$wavbytes"

# A fixture the shell failed to write would make every case below fail for a
# reason that has nothing to do with lame, so stop here rather than emit a dozen
# misleading reds against the wrong subject.
if [ "$wavbytes" != "32812" ]; then
  bst_notok lame/fixture "the shell could not emit the 32812-byte WAV fixture -- remaining cases not run"
  rm -rf "$tmp"
  exit 0
fi

# The reference was made from THIS byte string. Pinning its digest here is what
# lets a later cmp failure be read as an encoder difference rather than as
# fixture drift -- without it the two causes are indistinguishable, and the
# wrong one gets filed.
if command -v md5sum >/dev/null 2>&1; then
  check_eq lame/fixture-digest da93fc854f85a82305553d1080c0b66a \
                               "$(md5sum < "$wav" 2>/dev/null | cut -d' ' -f1)"
else
  bst_skip lame/fixture-digest "md5sum not installed on this image"
fi

check_out lame/version "3.100" lame --version

# ------------------------------------------------ the ticket's own criterion ---
check lame/encode lame --quiet -b 128 --cbr "$wav" "$mp3"

if [ ! -f "$ref" ]; then
  bst_notok lame/reference-present "$ref is not installed -- the reference encode did not ship"
else
  bst_ok lame/reference-present

  gotbytes=$(wc -c < "$mp3" 2>/dev/null | tr -d ' ')
  check_eq lame/encode-size 7104 "$gotbytes"

  # THE GATE.
  if cmp -s "$ref" "$mp3" 2>/dev/null; then
    bst_ok lame/matches-reference
  else
    # Report what was actually produced. A same-size/different-digest result and
    # a wildly-different-size result are different findings, and the detail line
    # is the only place a reader of the report can tell them apart.
    if command -v md5sum >/dev/null 2>&1; then
      gotmd5=$(md5sum < "$mp3" 2>/dev/null | cut -d' ' -f1)
    else
      gotmd5="(md5sum absent)"
    fi
    bst_notok lame/matches-reference \
      "encoded $gotbytes bytes md5=$gotmd5; reference is 7104 bytes md5=c15eb97bcb066cab224876c497f1e676"
  fi
fi

# ------------------------------------------------------- bitstream structure ---
# Independent of the reference: these say the output is a real MPEG-1 Layer III
# stream and not merely 7104 bytes that happen to compare equal. ff fb is the
# 11-bit frame sync plus MPEG-1, Layer III, no CRC.
check_eq lame/frame-sync "377 373" "$(dd if="$mp3" bs=1 count=2 2>/dev/null | od -An -to1 | tr -s ' ' | sed 's/^ //;s/ $//')"

# CBR output carries an "Info" header frame (the VBR frame's CBR spelling), and
# the encoder stamps its own version into the stream. Both are lame writing its
# identity into the bitstream, which is what makes a reference encode
# reproducible in the first place.
check_out lame/info-tag "Info" dd if="$mp3" bs=1 skip=21 count=4
check lame/lame-version-in-stream grep -q "LAME3.100" "$mp3"

# ------------------------------------------------------------- the CBR knob ---
# 64 / 128 / 320 kbps over the same input must give strictly increasing sizes.
# That is a property of constant-bitrate coding -- bytes per second is the knob
# -- and not of this fixture, which is why it is safe to assert where an
# equivalent claim about compression LEVELS would not be (see 57-flac.test).
lo=$tmp/lo.mp3; hi=$tmp/hi.mp3
if lame --quiet -b 64 --cbr "$wav" "$lo" 2>/dev/null &&
   lame --quiet -b 320 --cbr "$wav" "$hi" 2>/dev/null; then
  lob=$(wc -c < "$lo" | tr -d ' '); hib=$(wc -c < "$hi" | tr -d ' ')
  if [ "$lob" -lt "$gotbytes" ] && [ "$gotbytes" -lt "$hib" ]; then
    bst_ok lame/cbr-scales
  else
    bst_notok lame/cbr-scales "64k=$lob 128k=$gotbytes 320k=$hib -- not strictly increasing"
  fi
  # It must also actually be a codec: 128 kbps over 0.37 s of 705.6 kbps PCM.
  if [ "$gotbytes" -lt 32812 ]; then bst_ok lame/compresses
  else bst_notok lame/compresses "encoded $gotbytes bytes from a 32812-byte fixture -- no compression"; fi
else
  bst_notok lame/cbr-scales "encode failed at -b 64 or -b 320"
  bst_notok lame/compresses "encode failed at -b 64 or -b 320"
fi

# ----------------------------------------------------------------- decoding ---
# lame carries mpglib and decodes with --decode, so the port includes a decoder
# and it is worth holding to the same standard. The digest is of the WAV the
# host reference decoder produced from the very file in data/, so this is again
# an exact comparison against the identical release rather than a shape check.
dec=$tmp/back.wav
if lame --quiet --decode "$ref" "$dec" 2>/dev/null; then
  bst_ok lame/decode
  check_eq lame/decode-size 32812 "$(wc -c < "$dec" | tr -d ' ')"
  if command -v md5sum >/dev/null 2>&1; then
    check_eq lame/decode-matches-reference faa1ade6ec897c5590a25fea25304e17 \
                                           "$(md5sum < "$dec" 2>/dev/null | cut -d' ' -f1)"
  else
    bst_skip lame/decode-matches-reference "md5sum not installed on this image"
  fi
else
  bst_notok lame/decode "lame --decode failed on the shipped reference stream"
fi

# --------------------------------------------------------------------- id3 ---
# Tagging is a different code path from the encoder: one writer prepends before
# the first frame, the other appends after the last. --tt/--ta drives BOTH by
# default -- an ID3v2 header at offset 0 and the fixed 128-byte ID3v1 trailer --
# which is why the size below is not simply the encode plus 128, and why the two
# writers are asserted separately rather than through one number.
tagged=$tmp/tagged.mp3
if lame --quiet -b 128 --cbr --tt brintOS --ta Emcraft "$wav" "$tagged" 2>/dev/null; then
  bst_ok lame/id3-write
  check_eq lame/id3v2-header "ID3" "$(dd if="$tagged" bs=1 count=3 2>/dev/null)"
  # ID3v1 is a fixed-layout 128-byte trailer: "TAG" then a 30-byte title field.
  # The MAGIC is asserted unconditionally -- it is written by lame regardless of
  # what the title ends up containing.
  head33=$(tail -c 128 "$tagged" 2>/dev/null | dd bs=1 count=33 2>/dev/null)
  check_eq lame/id3v1-magic "TAG" "$(printf '%s' "$head33" | dd bs=1 count=3 2>/dev/null)"

  # THE TITLE TEXT IS PROBED, NOT ASSERTED, and this is the one place in the
  # suite where that is the honest shape. lame does not copy a tag string
  # through: parse.c's toLatin1() calloc's a zeroed buffer and fills it via
  # iconv_open("ISO_8859-1//TRANSLIT", nl_langinfo(CODESET)) -- and when that
  # open is REFUSED it returns the zeroed buffer, so the tag is written with an
  # empty title rather than failing. This image refuses every iconv_open: it
  # links statically, glibc serves charsets from dlopen'd gconv modules, and no
  # /usr/lib/gconv is staged (BRINTOS-184 established the mechanism through
  # mtools/CP850; BRINTOS-343 established that even the BUILTIN ISO-8859-1
  # transformation is refused). That is our own image content, not a brintOS
  # platform defect, so this is a skip carrying its witness -- and because the
  # witness is probed at run time, the case becomes a real green the day the
  # image ships gconv data, instead of sitting as a stale exemption. A title
  # that came back as neither "brintOS" nor empty is a third thing entirely and
  # stays a hard red.
  case "$head33" in
    TAGbrintOS*)
      bst_ok lame/id3v1-title ;;
    TAG)
      # The skip is gated on its own witness, so it cannot outlive its cause: an
      # empty title on an image that DOES carry gconv data is a genuine red, not
      # this exemption.
      if [ -d /usr/lib/gconv ]; then
        bst_notok lame/id3v1-title \
          "title empty although /usr/lib/gconv exists -- the iconv exemption no longer applies"
      else
        bst_skip lame/id3v1-title \
          "title empty: iconv_open refused, no /usr/lib/gconv on this static image (BRINTOS-184/343)"
      fi ;;
    *)
      bst_notok lame/id3v1-title "ID3v1 title field is neither 'brintOS' nor empty: '$head33'" ;;
  esac
else
  bst_notok lame/id3-write "lame --tt/--ta failed"
  bst_notok lame/id3v2-header "no tagged file to read"
  bst_notok lame/id3v1-magic "no tagged file to read"
  bst_notok lame/id3v1-title "no tagged file to read"
fi

# With ID3v2 declined the arithmetic is exact and the trailer is the ONLY thing
# added, so the 128 bytes can be asserted as a number rather than inferred.
v1=$tmp/v1.mp3
if lame --quiet -b 128 --cbr --id3v1-only --tt brintOS "$wav" "$v1" 2>/dev/null; then
  check_eq lame/id3v1-only-size $((gotbytes + 128)) "$(wc -c < "$v1" | tr -d ' ')"
else
  bst_notok lame/id3v1-only-size "lame --id3v1-only failed"
fi

# ------------------------------------------------------------- static-only ---
# No libmp3lame.so on a distro that configures --disable-shared image-wide. The
# recipe declares PACKAGES += "libmp3lame" with FILES = "${libdir}/libmp3lame.so.*",
# which matches nothing here -- which is why EMCRAFT_TOOLS names the bare `lame`
# and not that package. One appearing would mean the static-only rule silently
# stopped holding.
if [ -e /usr/lib/libmp3lame.so ] || [ -e /usr/lib/libmp3lame.so.0 ]; then
  bst_notok lame/static-only "a shared libmp3lame shipped on a --disable-shared distro"
else
  bst_ok lame/static-only
fi

# The GTK frame analyser. poky's no-gtk1.patch forces HAVE_GTK=no, so mp3x must
# not exist; one appearing would mean the patch stopped applying and the image
# grew a GTK dependency nobody asked for.
if [ -e /usr/bin/mp3x ]; then
  bst_notok lame/no-mp3x "mp3x shipped -- the GTK frame analyser was built despite no-gtk1.patch"
else
  bst_ok lame/no-mp3x
fi

rm -rf "$tmp"