#!/bin/bash

set -euo pipefail

ISO_PATH=""
HTTP_ROOT=""
MOUNT_DIR=""

usage() {
    cat <<'EOF'
Usage: sync_alma_tree.sh --iso FILE --http-root DIR [--mount-dir DIR]

Mount an AlmaLinux ISO read-only and copy its contents into an HTTP-served
install tree for PXE/Kickstart use.
EOF
}

while [[ $# -gt 0 ]]; do
    case "$1" in
        --iso)
            ISO_PATH="$2"
            shift 2
            ;;
        --http-root)
            HTTP_ROOT="$2"
            shift 2
            ;;
        --mount-dir)
            MOUNT_DIR="$2"
            shift 2
            ;;
        -h|--help)
            usage
            exit 0
            ;;
        *)
            echo "Unknown option: $1" >&2
            usage >&2
            exit 1
            ;;
    esac
done

if [[ -z "$ISO_PATH" || -z "$HTTP_ROOT" ]]; then
    usage >&2
    exit 1
fi

if [[ ! -f "$ISO_PATH" ]]; then
    echo "ISO not found: $ISO_PATH" >&2
    exit 1
fi

if [[ $EUID -ne 0 ]]; then
    echo "Re-running with sudo..."
    exec sudo "$0" "$@"
fi

if [[ -z "$MOUNT_DIR" ]]; then
    MOUNT_DIR="$(mktemp -d /tmp/alma-iso.XXXXXX)"
fi

cleanup() {
    if mountpoint -q "$MOUNT_DIR"; then
        umount "$MOUNT_DIR"
    fi
    rmdir "$MOUNT_DIR" 2>/dev/null || true
}

trap cleanup EXIT

mkdir -p "$HTTP_ROOT"
mount -o loop,ro "$ISO_PATH" "$MOUNT_DIR"
rsync -aH --delete "$MOUNT_DIR"/ "$HTTP_ROOT"/

echo "Synced AlmaLinux tree to $HTTP_ROOT"