#!/bin/bash
#
# Build EcoOS ISO using Docker
# This avoids needing to install live-build on the host
#
# Usage: ./docker-build.sh [--arch=amd64|arm64|rpi]
#

set -e

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
ISOBUILD_DIR="$(dirname "$SCRIPT_DIR")"
ECO_OS_DIR="$(dirname "$ISOBUILD_DIR")"

# Default architecture
TARGET_ARCH="amd64"

# Parse arguments
for arg in "$@"; do
    case $arg in
        --arch=*)
            TARGET_ARCH="${arg#*=}"
            ;;
        -h|--help)
            echo "Usage: $0 [--arch=amd64|arm64|rpi]"
            echo ""
            echo "Architectures:"
            echo "  amd64  - x86_64 with UEFI/GRUB boot (default)"
            echo "  arm64  - Generic ARM64 with UEFI/GRUB boot"
            echo "  rpi    - Raspberry Pi 3/4/5 with native bootloader"
            exit 0
            ;;
        *)
            echo "Unknown argument: $arg"
            echo "Use --help for usage information"
            exit 1
            ;;
    esac
done

# Validate architecture
case "$TARGET_ARCH" in
    amd64|arm64|rpi)
        ;;
    *)
        echo "ERROR: Invalid architecture '$TARGET_ARCH'"
        echo "Valid options: amd64, arm64, rpi"
        exit 1
        ;;
esac

# Determine output filename based on architecture
case "$TARGET_ARCH" in
    amd64)
        OUTPUT_FILE="ecoos.iso"
        ;;
    arm64)
        OUTPUT_FILE="ecoos-arm64.iso"
        ;;
    rpi)
        OUTPUT_FILE="ecoos-rpi.img"
        ;;
esac

echo "=== EcoOS ISO Builder (Docker) ==="
echo "Target architecture: $TARGET_ARCH"
echo "Output file: $OUTPUT_FILE"
echo ""

cd "$ECO_OS_DIR"

# Build the Docker image with architecture argument
echo "[1/2] Building Docker image for $TARGET_ARCH..."

# For ARM builds on x86 hosts, we need to use buildx with platform emulation
if [ "$TARGET_ARCH" = "arm64" ] || [ "$TARGET_ARCH" = "rpi" ]; then
    HOST_ARCH=$(uname -m)
    if [ "$HOST_ARCH" = "x86_64" ]; then
        echo "Cross-building ARM on x86_64 host - using Docker buildx with QEMU emulation"
        echo "Note: This requires QEMU binfmt. If this fails, run:"
        echo "  docker run --privileged --rm tonistiigi/binfmt --install all"
        echo ""

        # Ensure buildx is available and create builder if needed
        docker buildx inspect ecoos-builder >/dev/null 2>&1 || \
            docker buildx create --name ecoos-builder --use

        docker buildx build \
            --platform linux/arm64 \
            --build-arg TARGET_ARCH="$TARGET_ARCH" \
            --load \
            -t ecoos-builder-$TARGET_ARCH \
            -f isobuild/Dockerfile .
    else
        # Running on ARM host, use regular build
        docker build \
            --build-arg TARGET_ARCH="$TARGET_ARCH" \
            -t ecoos-builder-$TARGET_ARCH \
            -f isobuild/Dockerfile .
    fi
else
    docker build \
        --build-arg TARGET_ARCH="$TARGET_ARCH" \
        -t ecoos-builder-$TARGET_ARCH \
        -f isobuild/Dockerfile .
fi

# Run the build
echo ""
echo "[2/2] Building image (this may take 15-30 minutes)..."
mkdir -p "$ISOBUILD_DIR/output"

docker run --rm \
    --privileged \
    -e TARGET_ARCH="$TARGET_ARCH" \
    -v "$ISOBUILD_DIR/output:/output" \
    ecoos-builder-$TARGET_ARCH

echo ""
echo "=== Build Complete ==="
echo "Output: $ISOBUILD_DIR/output/$OUTPUT_FILE"