import { DOMParser, XMLSerializer } from 'xmldom'

/**
 * Expands the loop nodes in the XML document.
 * Returns the original document with the loops expanded.
 */
export const loopExpander = (xml: string): string => {
    const parser = new DOMParser()
    const dom = parser.parseFromString(xml, 'text/xml')

    const textNodes = Array.from(dom.getElementsByTagName('Text'))
        .filter((node) => node.getAttribute('repeat'))
        .map((node) => {
            const repeat = parseInt(node.getAttribute('repeat')!)
            const parent = node.parentNode!

            const nodes = Array.from({ length: repeat }, () => {
                const clone = node.cloneNode(true);
                (clone as Element).removeAttribute('repeat')
                return clone
            })

            return { parent, node, nodes }
        })

    textNodes.forEach(({ parent, node, nodes }) => {
        nodes.forEach((n) => parent.insertBefore(n, node))
        parent.removeChild(node)
    })

    return new XMLSerializer().serializeToString(dom)
}