#!/usr/bin/env bash
#
# scripts/boot.sh — quick direct boot in QEMU (dev loop)
#
# Builds the kernel, stages the system image, and boots directly as
# BOOTX64.EFI via QEMU's FAT driver.  One image = one drive.
#
# Usage:
#   ./scripts/boot.sh [--gui] [--debug] [--release] [--mem 512M] [--smp 2]
#
# Boot chain:  firmware → rsnix (direct)
# Full chain:  use ./scripts/boot-image.sh (firmware → rsboot → rsnix)
#
# Keybindings:
#   Ctrl-A X   — quit
#   Ctrl-A C   — QEMU monitor
#
# Environment:
#   OVMF    path to OVMF firmware (default: /usr/share/edk2/x64/OVMF.4m.fd)
#   MEM     memory size (default: 256M)
#   SMP     CPU count (default: 1)
#   SYSTEM_IMG  system image path (default: /tmp/system.img)
#
set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
PROJECT_DIR="$(cd "$SCRIPT_DIR/.." && pwd)"
cd "$PROJECT_DIR"

# ---- config ----
OVMF="${OVMF:-/usr/share/edk2/x64/OVMF.4m.fd}"
MEM="${MEM:-256M}"
SMP="${SMP:-1}"
SYSTEM_IMG="${SYSTEM_IMG:-/tmp/system.img}"
PROFILE="release"

GUI=""
DEBUG=""

# ---- args ----
source "$SCRIPT_DIR/lib-boot-args.sh"
handle_arg() {
	case "$1" in
	--debug)
		PROFILE="debug"
		CARGO_FLAGS=""
		;;
	*)
		echo "unknown: $1"
		exit 1
		;;
	esac
}
parse_boot_args "$@"

OUT_DIR="target/x86_64-unknown-uefi/$PROFILE"

# ---- build ----
echo "=== Building kernel ($PROFILE) ==="
if [ "$PROFILE" = "release" ]; then
	cargo build --release --package rsdos --target x86_64-unknown-uefi
else
	cargo build --package rsdos --target x86_64-unknown-uefi
fi

# ---- stage system image ----
echo "=== Staging system image ==="
"$SCRIPT_DIR/mksystem.sh" --force "$SYSTEM_IMG"
echo "  system image: $SYSTEM_IMG"

# ---- boot ----
echo ""
echo "=== Booting (direct: firmware → rsnix) ==="
echo "  ovmf:  $OVMF"
echo "  mem:   $MEM   smp: $SMP"
echo "  gui:   $([ -n "$GUI" ] && echo yes || echo no)"
echo "  gdb:   $([ -n "$DEBUG" ] && echo ':1234' || echo off)"
echo ""

exec qemu-system-x86_64 \
	-bios "$OVMF" \
	-drive "file=$SYSTEM_IMG,format=raw,if=none,id=disk" \
	-device ide-hd,drive=disk,bus=ide.0 \
	-serial stdio \
	-m "$MEM" \
	-machine q35 \
	-cpu qemu64 \
	-no-reboot \
	-smp "$SMP" \
	$GUI $DEBUG