#!/usr/bin/env bash
# Launch the IIgs sprite demo (or other example) under MAME's apple2gs
# driver instead of GSplus. We get:
#   - The MAME debugger window (always visible with -debug)
#   - debug.log file written to the working directory
#   - A Lua hook that, when the CPU halts (e.g., BRK), dumps registers
#     and the surrounding code bytes to /tmp/mame-iigs/crash.txt
#
# The boot path is the same as run-iigs.sh: gsos-system.po as flop3, our
# joey.2mg as flop4. Once Finder is up, navigate to JOEYLIB and double-
# click the example.
#
# Outputs of a run land in /tmp/mame-iigs/:
#   - debug.log         MAME's debugger console output (-debuglog)
#   - crash.txt         Lua-hook crash dump (if anything halts the CPU)
#   - joeylog.txt       Extracted from the post-run disk image

set -euo pipefail

prog=${1:-pattern}
repo=$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)

case $prog in
    hello|pattern|keys|joy|sprite|audio) ;;
    *) echo "usage: $0 [hello|pattern|keys|joy|sprite|audio]" >&2; exit 2 ;;
esac

sys_disk=$repo/toolchains/emulators/support/gsos-system.po
data_disk=$repo/build/iigs/bin/joey.2mg

for f in "$sys_disk" "$data_disk"; do
    if [[ ! -f $f ]]; then
        echo "missing: $f" >&2
        exit 1
    fi
done

work=$(mktemp -d -t joeylib-mame.XXXXXX)
out=/tmp/mame-iigs
mkdir -p "$out"

cp "$sys_disk"  "$work/boot.po"
cp "$data_disk" "$work/joey.2mg"

# Lua script: on every CPU stop (BRK, breakpoint, watchpoint, manual
# halt), append a state snapshot to crash.txt. This way we don't need
# the user to type anything at the debugger window -- whatever halts
# the CPU lands a record in crash.txt.
cat > "$work/crash-hook.lua" <<'LUA'
-- Crash diagnostics for IIgs demos. Auto-resumes the initial debug
-- pause so the user doesn't need to type "go". On any subsequent halt
-- (BRK, watchpoint, breakpoint) outside ROM, dumps registers + bytes
-- around PC to crash.txt. ROM halts (PB == 0xFE/0xFF) are skipped so
-- we don't fill the file with normal IIgs ROM stack walking.
local cpu     = manager.machine.devices[":maincpu"]
local prog    = cpu.spaces["program"]
local outpath = "/tmp/mame-iigs/crash.txt"

local function in_rom(pb)
    return pb == 0xFE or pb == 0xFF
end

local function dump(label)
    local f = io.open(outpath, "a")
    if f == nil then return end
    f:write(string.format("=== %s @ %s ===\n", label, os.date("%H:%M:%S")))
    for k, v in pairs(cpu.state) do
        f:write(string.format("  %s = %X\n", k, v.value))
    end
    local pc = cpu.state["CURPC"].value
    local lo = (pc - 16) & 0xFFFFFF
    f:write(string.format("  bytes %06X..%06X:", lo, lo + 32))
    for i = 0, 32 do
        local b = prog:read_u8(lo + i)
        f:write(string.format(" %02X", b))
    end
    f:write("\n")
    f:close()
end

-- Lua can't reliably terminate MAME from this version's API; instead
-- write a marker file and let the bash launcher poll for it and kill
-- the process. "done" file = launcher should shut down.
local done_marker = "/tmp/mame-iigs/.done"
local started = false
local crashed = false
local boot_frames = 0
local function signal_done(reason)
    local f = io.open(done_marker, "w")
    if f ~= nil then
        f:write(reason)
        f:close()
    end
end

emu.register_periodic(function()
    local dbg = manager.machine.debugger
    if dbg == nil then return end
    if dbg.execution_state == "stop" then
        if not started then
            -- First halt is the -debug startup pause; auto-resume so
            -- emulation begins without manual input.
            started = true
            dbg.execution_state = "run"
            return
        end
        if not crashed then
            crashed = true
            dump("halt")
            signal_done("halt")
        end
    else
        boot_frames = boot_frames + 1
        -- Watchdog: ~30 wall-sec at 60 Hz. If nothing crashes by
        -- then, dump current state (likely the demo running fine)
        -- and tell the launcher to shut down so we can grab joeylog.
        if boot_frames > 1800 and not crashed then
            crashed = true
            dump("watchdog")
            signal_done("watchdog")
        end
    end
end)
LUA

# Wipe prior crash.txt so we don't confuse runs.
: > "$out/crash.txt"

cat <<EOF
MAME apple2gs (auto-launch ${prog^^}):
  Boot disk:  $work/boot.po (flop3)

GS/OS will boot directly into ${prog^^}; no Finder navigation needed.
On crash the MAME debugger halts and Lua dumps state to:
  $out/crash.txt

After exit:
  $out/joeylog.txt    extracted from disk image
  $out/debug.log      MAME debugger console output

EOF

cleanup() {
    # Always rescue debug.log first -- it's written by MAME relative to
    # cwd ($work) and lost when the dir is removed.
    if [[ -f $work/debug.log ]]; then
        mv -f "$work/debug.log" "$out/debug.log"
    fi
    local profuse=$repo/toolchains/iigs/gg-tools/bin/profuse
    local mnt=$work/_mnt
    if [[ -x $profuse && -f $work/joey.2mg ]]; then
        export GOLDEN_GATE="$repo/toolchains/iigs/goldengate"
        export ORCA_ROOT="$GOLDEN_GATE"
        mkdir -p "$mnt"
        if "$profuse" -oro "$work/joey.2mg" "$mnt" 2>/dev/null; then
            for name in JOEYLOG.TXT joeylog.txt; do
                if [[ -f $mnt/$name ]]; then
                    cp "$mnt/$name" "$out/joeylog.txt"
                    echo "extracted joeylog.txt -> $out/joeylog.txt" >&2
                    break
                fi
            done
            fusermount -u "$mnt" 2>/dev/null || true
        fi
    fi
    rm -rf "$work"
}
trap cleanup EXIT

# Headless by default (-video none). Set MAME_WINDOW=1 to get a real
# emulator window for interactive use.
video_arg="-video none"
if [[ "${MAME_WINDOW:-0}" = "1" ]]; then
    video_arg="-window"
fi

# Clear the done-marker the Lua hook uses to signal shutdown.
rm -f "$out/.done"

cd "$work"
mame apple2gs \
    -flop3 "$work/boot.po" \
    -flop4 "$work/joey.2mg" \
    $video_arg -sound none \
    -debug -debuglog \
    -autoboot_script "$work/crash-hook.lua" &
mame_pid=$!

# Poll for the done-marker. Kill MAME once Lua signals it. Cap total
# wall-clock at 60 s in case MAME never writes the marker.
deadline=$((SECONDS + 60))
while kill -0 "$mame_pid" 2>/dev/null; do
    if [[ -f $out/.done ]]; then
        kill "$mame_pid" 2>/dev/null
        break
    fi
    if (( SECONDS > deadline )); then
        kill "$mame_pid" 2>/dev/null
        break
    fi
    sleep 0.5
done
wait "$mame_pid" 2>/dev/null || true