#!/usr/bin/env bash
# verify-amiga-audio.sh - Amiga audio gate, graded on recorded sound.
#
# Paula cannot be tapped register-by-register here: fs-uae has no trace
# facility and no debugger this harness can drive, so unlike the IIgs and
# ST gates (which read the DOC and the YM2149 directly) this one records
# what actually came out of the emulator and grades that.
#
# Capture path: fs-uae plays through OpenAL, OpenAL is pointed at
# PulseAudio with ALSOFT_DRIVERS=pulse, and PULSE_SINK sends this ONE
# process to a null sink created for the run -- the host's default sink is
# never touched, so the gate is safe to run on a desktop that is playing
# something else. parec then records that sink's monitor.
#
# What is graded: the AUDIO example is driven through four phases whose
# expected loudness differs by a wide margin.
#
#   music     the baked tracker song on entry, loud
#   paused    P pressed, near silence
#   sfx       SPACE during the pause, so ANY sound must be the digital SFX
#   resumed   P again, loud again
#
# Firing the SFX into a paused song is the point: mixed under the music an
# 8-bit one-shot barely moves the total and "did the SFX play" becomes a
# judgement call, while against silence it is unambiguous. Coexistence is
# still covered, because the music has to come back afterwards on the same
# hardware. Measured margins: music ~5700, paused ~240, sfx ~1170.
#
# Keys are HELD (keydown, pause, keyup), not tapped: the demo tests
# jlKeyPressed, an edge predicate polled once a frame, and a make/break
# delivered between two polls is never seen.
#
# --fullscreen=1 and --initial_input_grab=1 are REQUIRED under a WM-less
# Xvfb: SDL only accepts keyboard input once its window has focus, no
# window manager is there to grant it, and xdotool's XSendEvent route is
# ignored by SDL. A fullscreen SDL window takes focus itself, after which
# plain XTEST typing lands. Same reasoning as verify-amiga-input.sh.
#
# Usage:   scripts/verify-amiga-audio.sh [example]
#            example  binary name in build/amiga/bin, default Audio
# Env:     AMIGA_AUDIO_KEEP  set to keep the work dir and the WAV
# Requires: fs-uae, Xvfb, xdotool, parec/pactl (PulseAudio or PipeWire),
#           python3, toolchains/emulators/support/kickstart.rom,
#           build/amiga/bin/<example>
set -uo pipefail

repo=$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)
prog=${1:-Audio}
binDir=$repo/build/amiga/bin
kickstart=$repo/toolchains/emulators/support/kickstart.rom
grader=$repo/tools/gradeAudioPhases.py
label=verify-amiga-audio

[ -f "$kickstart" ] || { echo "$label: missing $kickstart" >&2; exit 2; }
[ -f "$grader" ] || { echo "$label: missing $grader" >&2; exit 2; }
for tool in fs-uae Xvfb xdotool parec pactl python3; do
    command -v "$tool" >/dev/null || { echo "$label: $tool not installed" >&2; exit 2; }
done
pactl info >/dev/null 2>&1 || { echo "$label: no PulseAudio/PipeWire server to record from" >&2; exit 2; }

if [ -d "$binDir/$prog" ]; then
    progDir=$binDir/$prog
elif [ -f "$binDir/$prog" ]; then
    progDir=""
else
    echo "$label: $binDir/$prog not built (run 'make amiga')" >&2
    exit 2
fi

work=$(mktemp -d -t joeylib-amaudio.XXXXXX)
sinkModule=""
display=":$((90 + RANDOM % 9))"
xvfbPid=""
fsPid=""
parecPid=""

cleanup() {
    [ -n "$parecPid" ] && kill "$parecPid" 2>/dev/null
    [ -n "$fsPid" ] && kill "$fsPid" 2>/dev/null
    [ -n "$xvfbPid" ] && kill "$xvfbPid" 2>/dev/null
    # Always unload the sink: leaving null sinks behind on the user's
    # audio server is the one side effect this gate could have.
    [ -n "$sinkModule" ] && pactl unload-module "$sinkModule" 2>/dev/null
    if [ -n "${AMIGA_AUDIO_KEEP:-}" ]; then
        echo "$label: kept $work" >&2
    else
        rm -rf "$work"
    fi
    return 0
}
trap cleanup EXIT

# Stage the Amiga volume exactly as run-amiga-headless.sh does.
mkdir -p "$work/hd/s"
if [ -n "$progDir" ]; then
    cp -r "$progDir/." "$work/hd/"
else
    find "$binDir" -maxdepth 1 -type f -executable -exec cp -t "$work/hd/" {} +
    [ -d "$binDir/DATA" ] && cp -r "$binDir/DATA" "$work/hd/"
fi
printf 'stack 32768\n:%s\n' "$prog" > "$work/hd/s/startup-sequence"

sinkName="joeyAudioGate$$"
sinkModule=$(pactl load-module module-null-sink \
    sink_name="$sinkName" \
    sink_properties=device.description="$sinkName" 2>/dev/null) || sinkModule=""
[ -n "$sinkModule" ] || { echo "$label: could not create a null sink to record from" >&2; exit 2; }

Xvfb "$display" -screen 0 800x600x24 -nolisten tcp >/dev/null 2>&1 &
xvfbPid=$!
sleep 1

# --fast_memory=0 --slow_memory=0 keeps this a bare A500, the port's floor.
DISPLAY="$display" PULSE_SINK="$sinkName" ALSOFT_DRIVERS=pulse SDL_AUDIODRIVER=pulse \
    fs-uae \
    --amiga_model=A500 \
    --hard_drive_0="$work/hd" \
    --hard_drive_0_label=JOEYLIB \
    --kickstart_file="$kickstart" \
    --fullscreen=1 \
    --initial_input_grab=1 \
    --fade_out_duration=0 \
    --fast_memory=0 \
    --slow_memory=0 \
    > "$work/fsuae.log" 2>&1 &
fsPid=$!

# Let Kickstart boot and the startup-sequence reach the program.
sleep 12
if ! kill -0 "$fsPid" 2>/dev/null; then
    echo "$label: FAIL - fs-uae exited before the program started" >&2
    tail -5 "$work/fsuae.log" >&2
    exit 1
fi

parec --device="$sinkName.monitor" --format=s16le --rate=44100 --channels=2 \
    --file-format=wav "$work/out.wav" > "$work/parec.log" 2>&1 &
parecPid=$!

win=$(DISPLAY="$display" xdotool search --name -- "FS-UAE" | head -1)
if [ -z "$win" ]; then
    echo "$label: FAIL - no FS-UAE window to send keys to" >&2
    exit 1
fi
DISPLAY="$display" xdotool windowactivate --sync "$win" 2>/dev/null

hold() {                                        # $1 = key name
    DISPLAY="$display" xdotool keydown --window "$win" "$1"
    sleep 0.4
    DISPLAY="$display" xdotool keyup --window "$win" "$1"
}

# The phase boundaries below are the timestamps handed to the grader, so
# the sleeps and the spec must stay in step.
sleep 6                                         # 0-6s   music
hold p                                          # ->     paused
sleep 8                                         # 6-14s  paused
for _ in 1 2 3; do                              # 14-24s sfx into silence
    hold space
    sleep 1.5
done
sleep 4
hold p                                          # ->     resumed
sleep 9                                         # 24-33s resumed

kill "$parecPid" 2>/dev/null
parecPid=""
sleep 1

[ -s "$work/out.wav" ] || { echo "$label: FAIL - recorded no audio at all" >&2; exit 1; }

# Thresholds sit far from the measured values (music ~5700, paused ~240,
# sfx ~1170) so ordinary mixing jitter cannot flip the verdict.
python3 "$grader" "$label" "$work/out.wav" \
    "music:1:5:2000:" \
    "paused:8:13::800" \
    "sfx:16:22:800:" \
    "resumed:27:32:2000:"
status=$?
[ -n "${AMIGA_AUDIO_KEEP:-}" ] && cp "$work/out.wav" "$repo/build/amiga/headless-audio.wav" 2>/dev/null
exit $status