#!/bin/bash
# Build daedalus-v4l2_<ver>_arm64.deb (userspace daemon + test tools).
#
# Mirrors arch/daedalus-v4l2 (Arch Linux build).  The companion DKMS
# package (debian/daedalus-v4l2-dkms) carries the kernel module
# separately so apt/dpkg can split kernel-version-tied and userspace
# upgrade cadence.
#
# Sibling Arch package: ../../arch/daedalus-v4l2/PKGBUILD
# Sibling DKMS package: ../daedalus-v4l2-dkms/build-deb.sh
# Upstream repo: https://git.reauktion.de/reauktion/daedalus-v4l2
set -euo pipefail

# Same pin as the Arch PKGBUILD.  481279c = "Phase 8.13: byte-exact
# end-to-end via libva (consumer target hit)" — first commit where the
# full ffmpeg -hwaccel vaapi → libva → /dev/video0 → daemon path lands
# a pixel-correct decoded frame back in ffmpeg.
UPSTREAM_COMMIT=f0d41867f60f5bf8dbfcc6cc16404d7d7eb90014
PKGVER=0.1.0+r24+gf0d4186
PKGREL=1  # reset for new upstream pin (3dd0eb0 — DAEMON-PPS H.264 SPS/PPS NAL synth)

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 "$work"
curl --connect-timeout 10 --max-time 600 --retry 3 --retry-delay 5 -sSLfo daedalus-v4l2.tar.gz \
    "https://git.reauktion.de/reauktion/daedalus-v4l2/archive/${UPSTREAM_COMMIT}.tar.gz"
tar xzf daedalus-v4l2.tar.gz
SRCDIR=daedalus-v4l2

# Build daemon (CMake)
cd "$SRCDIR/daemon"
cmake -B build -G Ninja \
    -DCMAKE_BUILD_TYPE=Release \
    -DCMAKE_INSTALL_PREFIX=/usr
cmake --build build

# Build test tools (in-tree Makefile)
cd "$work/$SRCDIR/tools"
make

# Stage
ROOT="$work/pkgroot"
mkdir -p "$ROOT/DEBIAN" \
         "$ROOT/usr/bin" \
         "$ROOT/usr/libexec/daedalus-v4l2" \
         "$ROOT/usr/include" \
         "$ROOT/usr/share/doc/daedalus-v4l2" \
         "$ROOT/lib/systemd/system" \
         "$ROOT/usr/lib/modules-load.d"

install -m 755 "$work/$SRCDIR/daemon/build/daedalus_v4l2_daemon" \
    "$ROOT/usr/bin/daedalus_v4l2_daemon"

install -m 755 "$work/$SRCDIR/tools/test_chardev_pingpong" \
    "$ROOT/usr/libexec/daedalus-v4l2/test_chardev_pingpong"
install -m 755 "$work/$SRCDIR/tools/test_m2m_decode" \
    "$ROOT/usr/libexec/daedalus-v4l2/test_m2m_decode"
install -m 755 "$work/$SRCDIR/tools/test_m2m_stream" \
    "$ROOT/usr/libexec/daedalus-v4l2/test_m2m_stream"

install -m 644 "$work/$SRCDIR/include/daedalus_v4l2_proto.h" \
    "$ROOT/usr/include/daedalus_v4l2_proto.h"

# systemd unit + module autoload — without these the daemon never
# starts and the libva/VAAPI consumer's REQ_DECODE has nobody on
# the other end of /dev/daedalus-v4l2.
install -m 644 "$work/$SRCDIR/packaging/systemd/daedalus-v4l2.service" \
    "$ROOT/lib/systemd/system/daedalus-v4l2.service"
install -m 644 "$work/$SRCDIR/packaging/systemd/daedalus-v4l2.modules-load" \
    "$ROOT/usr/lib/modules-load.d/daedalus-v4l2.conf"

install -m 644 "$work/$SRCDIR/README.md" \
    "$ROOT/usr/share/doc/daedalus-v4l2/README.md"
for d in "$work/$SRCDIR/docs/"*.md; do
    install -m 644 "$d" "$ROOT/usr/share/doc/daedalus-v4l2/$(basename "$d")"
done

install -Dm644 "$HERE/debian/copyright" "$ROOT/usr/share/doc/daedalus-v4l2/copyright"
install -Dm644 "$HERE/debian/changelog" "$ROOT/usr/share/doc/daedalus-v4l2/changelog.Debian"
gzip -9 -n "$ROOT/usr/share/doc/daedalus-v4l2/changelog.Debian"

# DEBIAN/postinst — enable service + reload modules-load.d so the
# kernel module loads now if daedalus-v4l2-dkms is also installed.
# Does NOT auto-start the service — that requires /dev/daedalus-v4l2
# to already exist (the ConditionPathExists= in the .service file)
# which may not be true on the very first install before the user
# reboots or manually modprobes.  Operator decides when to start.
cat > "$ROOT/DEBIAN/postinst" <<'POSTINST'
#!/bin/sh
set -e

if [ "$1" = "configure" ]; then
    # Reload systemd so the new unit file is visible.
    if command -v systemctl >/dev/null 2>&1; then
        systemctl daemon-reload >/dev/null 2>&1 || true
        systemctl enable daedalus-v4l2.service >/dev/null 2>&1 || true
    fi

    # Trigger /usr/lib/modules-load.d/daedalus-v4l2.conf without a
    # reboot.  Harmless if the module is already loaded; logs to
    # journal if it can't load (most common cause: dkms hasn't built
    # the module yet for the running kernel — see daedalus-v4l2-dkms
    # postinst for the loud-warning path).
    if command -v systemd-modules-load >/dev/null 2>&1; then
        systemd-modules-load >/dev/null 2>&1 || true
    fi

    # Auto-start if /dev/daedalus-v4l2 came up (i.e. module loaded
    # successfully).  ConditionPathExists in the unit file means
    # `systemctl start` is a no-op if the device isn't there yet —
    # avoids spurious failures during apt install on a host where
    # daedalus-v4l2-dkms hasn't built yet.
    if [ -e /dev/daedalus-v4l2 ] && command -v systemctl >/dev/null 2>&1; then
        systemctl start daedalus-v4l2.service >/dev/null 2>&1 || true
    fi
fi

#DEBHELPER#
POSTINST
chmod 755 "$ROOT/DEBIAN/postinst"

cat > "$ROOT/DEBIAN/prerm" <<'PRERM'
#!/bin/sh
set -e

if [ "$1" = "remove" ] && command -v systemctl >/dev/null 2>&1; then
    systemctl stop    daedalus-v4l2.service >/dev/null 2>&1 || true
    systemctl disable daedalus-v4l2.service >/dev/null 2>&1 || true
fi

#DEBHELPER#
PRERM
chmod 755 "$ROOT/DEBIAN/prerm"

cat > "$ROOT/DEBIAN/postrm" <<'POSTRM'
#!/bin/sh
set -e

if command -v systemctl >/dev/null 2>&1; then
    systemctl daemon-reload >/dev/null 2>&1 || true
fi

#DEBHELPER#
POSTRM
chmod 755 "$ROOT/DEBIAN/postrm"

cat > "$ROOT/DEBIAN/control" <<EOF
Package: daedalus-v4l2
Version: ${PKGVER}-${PKGREL}
Section: video
Priority: optional
Architecture: arm64
Depends: ffmpeg-v4l2-request-fourier (>= 2:8.1+rfourier), libdrm2
Recommends: daedalus-v4l2-dkms
Maintainer: Markus Fritsche <mfritsche@reauktion.de>
Homepage: https://git.reauktion.de/reauktion/daedalus-v4l2
Description: Userspace daemon for the daedalus_v4l2 stateless decoder shim
 daedalus-v4l2 ships the userspace daemon that backs the daedalus_v4l2
 out-of-tree V4L2 kernel module on Raspberry Pi 5 / CM5.  Together they
 expose /dev/videoNN + /dev/mediaNN as a V4L2 stateless decoder for
 VP9, AV1, and H.264 — actual decoding happens in this single-threaded
 daemon via dlopen'd FFmpeg, with decoded NV12 / P010 frames shipped
 back through dmabuf.
 .
 Consumed end-to-end by libva-v4l2-request-fourier (>= 1.0.0+r376) so
 that 'ffmpeg -hwaccel vaapi' against vp9_small.ivf produces a
 byte-exact NV12 frame.
 .
 The kernel module ships separately in daedalus-v4l2-dkms; install
 both to actually serve V4L2 clients.
EOF

DEB_OUT="daedalus-v4l2_${PKGVER}-${PKGREL}_arm64.deb"
dpkg-deb --root-owner-group --build "$ROOT" "$HERE/$DEB_OUT"
echo "built: $HERE/$DEB_OUT"