#!/bin/bash
# Build ffmpeg-v4l2-request-fourier_<ver>_arm64.deb (the Kwiboo FFmpeg
# fork with the V4L2-Request API hwaccel patches).
#
# Mirror of arch/ffmpeg-v4l2-request-fourier into the Debian tree.
# Provides the patched `ffmpeg` + `ffprobe` binaries plus the shared
# libav* libraries with v4l2-request support, so consumers like
# mpv-fourier (and the kdirect bit-exact reference test rig) work
# end-to-end without a stock-Debian FFmpeg fallback.
#
# **Private prefix /opt/fourier** (Path A per fourier-debian
# architecture discussion 2026-05-19).  Stock Debian trixie ships
# FFmpeg 7.1.x = libavcodec.so.61; this package ships FFmpeg 8.1 =
# libavcodec.so.62 — different SOVERSION, NOT a drop-in for trixie's
# KDE/VLC/etc.  Living in /opt/fourier/lib keeps the stock system
# intact; only fourier-aware consumers (firefox-fourier, mpv-fourier,
# daedalus-v4l2) RPATH into /opt/fourier/lib.  Postinst drops an
# ld.so.conf.d entry so dlopen-based consumers (firefox at runtime)
# find the libs by SONAME without LD_LIBRARY_PATH wrappers.
#
# Big build: 25-40 min on a runner.  Output is a single .deb that
# bundles ffmpeg/ffprobe + libavcodec.so.62 + libavformat.so.62 etc.
# all together — no split per-library subpackages.  Easier to consume,
# trades off finer-grained downgrades.
#
# Sibling Arch package: ../../arch/ffmpeg-v4l2-request-fourier/PKGBUILD
# Upstream: https://github.com/Kwiboo/FFmpeg (branch v4l2-request-n8.1)
set -euo pipefail

# Same pin as arch/ — v4l2-request-n8.1 tip 2026-04-24.
UPSTREAM_COMMIT=b57fbbe50c9b2656fad86a1a7eeabfd2b2a50935
FFMPEG_VERSION=8.1
# epoch 2 matches Debian's stock ffmpeg (currently 7:7.1.x in trixie);
# +rfourier suffix to avoid colliding with upstream/Debian rebuilds.
PKGVER=2:${FFMPEG_VERSION}+rfourier+gb57fbbe
PKGREL=2  # pkgrel=2 — Path A move to /opt/fourier prefix (2026-05-19)

HERE=$(dirname "$(readlink -f "$0")")

# Reproducible build.  2026-05-18 23:00 UTC — Phase 8.13 close.
export SOURCE_DATE_EPOCH=1779231600

work=$(mktemp -d)
trap "rm -rf $work" EXIT

cd "$work"
git clone --depth 1 \
    --branch v4l2-request-n8.1 \
    https://github.com/Kwiboo/FFmpeg.git FFmpeg
cd FFmpeg
# git fetch the specific commit (depth=1 of branch tip might not be it)
if [ "$(git rev-parse HEAD)" != "$UPSTREAM_COMMIT" ]; then
    git fetch origin "$UPSTREAM_COMMIT"
    git checkout "$UPSTREAM_COMMIT"
fi

# Apply patches (same as Arch).
patch -Np1 -i "$HERE/0001-libudev-bypass-fallback.patch"
patch -Np1 -i "$HERE/0002-nv15-to-p010-unpack.patch"

# Configure with Arch-parity flags.  Drops the same set of features
# (X11, AMF, CUDA, FireWire, AviSynth, Bluray, OpenMPT, JPEG-XL,
# Theora, XVid, rsvg, soxr, ssh, vidstab, modplug, SDL2, Vulkan,
# JACK, GSM, Speex) — not needed on the Fourier fleet, keeps the .deb
# smaller and the dependency graph tighter.
./configure \
    --prefix=/opt/fourier \
    --bindir=/opt/fourier/bin \
    --libdir=/opt/fourier/lib \
    --shlibdir=/opt/fourier/lib \
    --incdir=/opt/fourier/include \
    --datadir=/opt/fourier/share/ffmpeg \
    --mandir=/opt/fourier/share/man \
    --extra-ldexeflags='-Wl,-rpath,/opt/fourier/lib' \
    --extra-ldsoflags='-Wl,-rpath,/opt/fourier/lib' \
    --disable-debug \
    --disable-static \
    --disable-doc \
    --disable-stripping \
    --enable-shared \
    --enable-gpl \
    --enable-version3 \
    --enable-pic \
    --enable-neon \
    --arch=aarch64 \
    --enable-libdrm \
    --enable-libv4l2 \
    --enable-libudev \
    --enable-v4l2-request \
    --enable-v4l2_m2m \
    --enable-vaapi \
    --enable-opengl \
    --enable-gnutls \
    --enable-fontconfig \
    --enable-libass \
    --enable-libfreetype \
    --enable-libfribidi \
    --enable-libxml2 \
    --enable-libpulse \
    --enable-libdav1d \
    --enable-libopus \
    --enable-libvorbis \
    --enable-libmp3lame \
    --enable-libvpx \
    --enable-libx264 \
    --enable-libx265 \
    --enable-libwebp \
    --host-cflags='-fPIC'

make -j"$(nproc)"
make tools/qt-faststart

# Stage
ROOT="$work/pkgroot"
make DESTDIR="$ROOT" install
install -Dm755 tools/qt-faststart "$ROOT/opt/fourier/bin/qt-faststart"

# ld.so.conf.d entry so dlopen-based consumers (firefox-fourier at
# runtime) find /opt/fourier/lib/libavcodec.so.62 by SONAME without an
# LD_LIBRARY_PATH wrapper.  No risk of contaminating stock binaries:
# stock KDE/VLC link against libavcodec.so.61 (different SONAME), so
# the loader never sees our .so.62 as a match for their .so.61.
install -Dm644 /dev/stdin "$ROOT/etc/ld.so.conf.d/fourier.conf" <<EOF
# fourier campaign: FFmpeg 8.1 fork + libVA fork in private prefix.
/opt/fourier/lib
EOF

# Optional /usr/bin shims so users can call ffmpeg-fourier without
# remembering the /opt path.  No conflict with stock /usr/bin/ffmpeg.
install -d "$ROOT/usr/bin"
ln -sf /opt/fourier/bin/ffmpeg   "$ROOT/usr/bin/ffmpeg-fourier"
ln -sf /opt/fourier/bin/ffprobe  "$ROOT/usr/bin/ffprobe-fourier"

# Doc
mkdir -p "$ROOT/usr/share/doc/ffmpeg-v4l2-request-fourier" "$ROOT/DEBIAN"
install -Dm644 "$HERE/debian/copyright" \
    "$ROOT/usr/share/doc/ffmpeg-v4l2-request-fourier/copyright"
install -Dm644 "$HERE/debian/changelog" \
    "$ROOT/usr/share/doc/ffmpeg-v4l2-request-fourier/changelog.Debian"
gzip -9 -n "$ROOT/usr/share/doc/ffmpeg-v4l2-request-fourier/changelog.Debian"

cat > "$ROOT/DEBIAN/control" <<EOF
Package: ffmpeg-v4l2-request-fourier
Version: ${PKGVER}-${PKGREL}
Section: video
Priority: optional
Architecture: arm64
Depends: libc6,
         libdrm2,
         libfontconfig1,
         libfreetype6,
         libfribidi0,
         libxml2,
         libpulse0,
         libdav1d7 | libdav1d6,
         libopus0,
         libvorbis0a,
         libvorbisenc2,
         libmp3lame0,
         libvpx9 | libvpx8 | libvpx7,
         libx264-164 | libx264-163,
         libx265-215 | libx265-209 | libx265-199,
         libwebp7 | libwebp6,
         libwebpmux3,
         libass9,
         libgnutls30,
         libudev1,
         libv4l-0,
         libva2,
         libva-drm2
Maintainer: Markus Fritsche <mfritsche@reauktion.de>
Homepage: https://github.com/Kwiboo/FFmpeg
Description: FFmpeg with V4L2 Request API hwaccel (Kwiboo fork, /opt/fourier prefix)
 FFmpeg ${FFMPEG_VERSION} patched with the V4L2 Request API stateless
 video decoder hwaccel — Kwiboo's long-running rebase of Jernej
 Škrabec's v4l2-request patchset onto FFmpeg release tags.
 .
 Provides 'ffmpeg -hwaccel v4l2request' / '-hwaccel drm' routes that
 drive rkvdec / hantro / cedrus / rpi-hevc-dec / daedalus_v4l2
 stateless decoders directly through libavcodec's hwdevice DRM path,
 bypassing libva.  Used by mpv-fourier and firefox-fourier as their
 backing FFmpeg, and as the kdirect bit-exact reference in libva-v4l2-
 request-fourier validation.
 .
 INSTALLED TO /opt/fourier (NOT /usr): this is FFmpeg 8.1 (libav*.so.62)
 sitting alongside Debian trixie's stock FFmpeg 7.1 (libav*.so.61) —
 different SONAMEs, no symbol clash.  Consumer binaries RPATH into
 /opt/fourier/lib; ld.so.conf.d/fourier.conf adds the path to ld.so
 cache for dlopen-by-SONAME (firefox).  /usr/bin/ffmpeg-fourier and
 /usr/bin/ffprobe-fourier are convenience symlinks to /opt/fourier/bin.
 Stock 'ffmpeg' command unaffected.
 .
 Drops X11/AMF/CUDA/Bluray/JACK/Vulkan/SDL2/Theora/XVid/Speex/JPEG-XL
 per Fourier fleet policy (Wayland + ARM + video-decode focus).
 No 'ffplay' binary; mpv-fourier covers interactive playback.
EOF

# ldconfig must be re-run after install so /opt/fourier/lib is in the cache.
cat > "$ROOT/DEBIAN/postinst" <<'PEOF'
#!/bin/sh
set -e
if [ "$1" = "configure" ]; then
    ldconfig
fi
#DEBHELPER#
PEOF
chmod 755 "$ROOT/DEBIAN/postinst"

cat > "$ROOT/DEBIAN/postrm" <<'PEOF'
#!/bin/sh
set -e
if [ "$1" = "remove" ] || [ "$1" = "purge" ]; then
    ldconfig
fi
#DEBHELPER#
PEOF
chmod 755 "$ROOT/DEBIAN/postrm"

DEB_OUT="ffmpeg-v4l2-request-fourier_${PKGVER//:/%3a}-${PKGREL}_arm64.deb"
dpkg-deb --root-owner-group --build "$ROOT" "$HERE/$DEB_OUT"
echo "built: $HERE/$DEB_OUT"