#!/usr/bin/env bash
#
# scripts/run.sh — build, stage and boot the system image in QEMU.
#
# Usage:
#   ./scripts/run.sh                 build + stage + boot (window + serial)
#   ./scripts/run.sh --headless      serial console only, no window
#   ./scripts/run.sh --debug         GDB stub on :1234, CPU starts paused
#                                    (attach: gdb -x scripts/debug-kernel.py)
#   ./scripts/run.sh --monitor       HMP monitor socket for sendkeys.py /
#                                    test-focus.py (default path below)
#   ./scripts/run.sh --fresh         re-create the system image first
#                                    (wipes runtime data on the image)
#   ./scripts/run.sh --mem 512M      guest memory (default 256M)
#   ./scripts/run.sh --smp 2         guest CPUs (default 1)
#   ./scripts/run.sh --bios FILE     OVMF firmware (default: system path)
#   ./scripts/run.sh --image FILE    system image (default: /tmp/system.img)
#   ./scripts/run.sh --grab          confine the pointer: GTK runs as an X11
#                                    (XWayland) client and grabs on hover
#   ./scripts/run.sh --no-grab       Wayland-native window, no pointer grab
#
# Mouse:  Wayland forbids global pointer grabs, so a Wayland-native window
#         cannot confine the cursor (QEMU's grab silently does nothing).
#         In a Wayland session with XWayland, run.sh defaults to --grab;
#         Ctrl+Alt+G toggles the grab in either mode.
#
# Environment (same names the other scripts honour): TARGET, PROFILE,
# SYSTEM_IMG, OVMF, QEMU, MEM, SMP.
#
# Two-command flow:      ./scripts/build.sh && ./scripts/run.sh
# One-command flow:      ./scripts/run.sh        (builds what is missing)
#
# Monitor socket:        /tmp/rsdos-monitor.sock
#
set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"

usage() {
	awk 'NR > 1 && /^#/ { sub(/^# ?/, ""); print; next } NR > 1 { exit }' "$0"
}

HEADLESS=0
DEBUG=0
FRESH=0
MON=0
MON_SOCK="/tmp/rsdos-monitor.sock"
GRAB="" # "" = auto: grab when a Wayland session has XWayland

while [ $# -gt 0 ]; do
	case "$1" in
	--headless | -H) HEADLESS=1 ;;
	# GDB stub + keep whatever profile the env asked for (release is the
	# default; PROFILE=debug ./scripts/run.sh --debug adds line symbols).
	--debug | -d) DEBUG=1 ;;
	--fresh) FRESH=1 ;;
	--monitor) MON=1 ;;
	--mem) shift; MEM="$1" ;;
	--smp) shift; SMP="$1" ;;
	--bios) shift; OVMF="$1" ;;
	--image | -i) shift; SYSTEM_IMG="$1" ;;
	--grab) GRAB=1 ;;
	--no-grab) GRAB=0 ;;
	--help | -h)
		usage
		exit 0
		;;
	*)
		echo "run.sh: unknown argument: $1" >&2
		usage >&2
		exit 1
		;;
	esac
	shift
done

# shellcheck source=lib.sh
source "$SCRIPT_DIR/lib.sh" # reads MEM/SMP/OVMF/SYSTEM_IMG from the env

# build.sh is a separate process: it re-derives OUT_DIR/KERNEL from these,
# so whatever we resolved above (including a --mem/--bios override) wins
# there too.
export TARGET PROFILE QEMU MEM SMP OVMF SYSTEM_IMG

# ---- mouse grab (Wayland) --------------------------------------------------
# Wayland forbids global pointer grabs, so a Wayland-native GTK window cannot
# confine the cursor — QEMU's grab silently does nothing there.  XWayland can,
# so a Wayland session that has XWayland (DISPLAY set) defaults to GTK-on-X11
# plus grab-on-hover.  Ctrl+Alt+G toggles the grab; --no-grab keeps the
# Wayland-native window.
if [ -z "$GRAB" ]; then
	if [ "${XDG_SESSION_TYPE:-}" = "wayland" ] && [ -n "${DISPLAY:-}" ]; then
		GRAB=1
	else
		GRAB=0
	fi
fi
[ "$HEADLESS" -eq 1 ] && GRAB=0 # no window, nothing to grab
if [ "$GRAB" -eq 1 ]; then
	if [ -n "${DISPLAY:-}" ]; then
		export GDK_BACKEND=x11
	else
		echo "run.sh: --grab needs XWayland (DISPLAY is unset); not grabbing" >&2
		GRAB=0
	fi
fi

# ---- build + stage --------------------------------------------------------
"$SCRIPT_DIR/build.sh"
if [ "$FRESH" -eq 1 ]; then
	stage_image --force
else
	stage_image
fi

# ---- boot -----------------------------------------------------------------
mapfile -t QARGS < <(qemu_args)
if [ "$HEADLESS" -eq 1 ]; then
	QARGS+=(-display none)
else
	QARGS+=(-vga std)
	if [ "$GRAB" -eq 1 ]; then
		QARGS+=(-display gtk,grab-on-hover=on)
	fi
fi
[ "$MON" -eq 1 ] && QARGS+=(-monitor "unix:$MON_SOCK,server,nowait")
[ "$DEBUG" -eq 1 ] && QARGS+=(-s -S)
QARGS+=(-serial stdio)

echo ""
echo "=== boot ==="
echo "  image:  $SYSTEM_IMG"
echo "  ovmf:   $OVMF"
echo "  mem:    $MEM   smp: $SMP"
echo "  mode:   $([ "$HEADLESS" -eq 1 ] && echo headless || echo window)   gdb: $([ "$DEBUG" -eq 1 ] && echo ':1234 (paused)' || echo off)"
if [ "$HEADLESS" -eq 0 ]; then
	echo "  mouse:  $([ "$GRAB" -eq 1 ] && echo 'grab on hover (XWayland; Ctrl+Alt+G toggles)' || echo 'not grabbed (Wayland cannot confine the pointer)')"
fi
[ "$MON" -eq 1 ] && echo "  monitor: unix:$MON_SOCK"
echo ""

exec "$QEMU" "${QARGS[@]}"