#!/bin/bash
set -e

# Image configuration
IMAGE_NAME="disk.img"
IMAGE_SIZE_MB=64
ESP_SIZE_MB=32  # EFI System Partition size

# Create a new disk image
dd if=/dev/zero of=$IMAGE_NAME bs=1M count=$IMAGE_SIZE_MB

# Create partition table and ESP partition
parted $IMAGE_NAME mklabel gpt
parted $IMAGE_NAME mkpart ESP fat32 1MiB ${ESP_SIZE_MB}MiB
parted $IMAGE_NAME set 1 esp on

# Calculate offset for mounting
SECTOR_SIZE=512
START_SECTOR=$(parted $IMAGE_NAME -ms unit s print | grep "^1:" | cut -d: -f2 | tr -d 's')
OFFSET=$((START_SECTOR * SECTOR_SIZE))

# Create FAT32 filesystem
LOOP_DEVICE=$(sudo losetup -f --show -o $OFFSET $IMAGE_NAME)
sudo mkfs.fat -F 32 $LOOP_DEVICE

# Mount the image
MOUNT_POINT="/tmp/esp"
mkdir -p $MOUNT_POINT
sudo mount $LOOP_DEVICE $MOUNT_POINT

# Create EFI directory structure
sudo mkdir -p $MOUNT_POINT/EFI/BOOT

# Copy kernel to the ESP
# For UEFI boot, rename it to BOOTX64.EFI
sudo cp target/x86_64-custom/release/kernel $MOUNT_POINT/EFI/BOOT/BOOTX64.EFI

# For BIOS boot, also copy it to the root
sudo cp target/x86_64-custom/release/kernel $MOUNT_POINT/

# Cleanup
sudo umount $MOUNT_POINT
sudo losetup -d $LOOP_DEVICE
rm -rf $MOUNT_POINT

echo "Disk image created successfully!"