feat: Filemagedon

Signed-off-by: Avior <git@avior.me>

src/libs/FilesFormats/XLSX.ts

@@ -0,0 +1,93 @@
+import { objectRemap } from '@dzeio/object-util'
+import AdmZip from 'adm-zip'
+import CSV from './CSV'
+import XML, { type Tag } from './XML'
+
+export default class XLSX {
+	/**
+	 *
+	 * @param xlsx the xlsx data as a buffer
+	 * @returns a Record with each sheets and the raw CSV linked to it
+	 */
+	public static async parse(xlsx: ArrayBuffer): Promise<Record<string, string>> {
+		const zip = new AdmZip(Buffer.from(xlsx))
+		const shared = await XML.parse(zip.readAsText('xl/sharedStrings.xml'))
+		const workbook = zip.readAsText('xl/workbook.xml')
+		const relations = zip.readAsText('xl/_rels/workbook.xml.rels')
+		const sheetsRelations = await XML.parse(relations)
+		const sheetsList = XML.findChild(await XML.parse(workbook), 'sheets')!.childs?.map((it) => ({
+			name: XML.getAttribute(it as Tag, 'name'),
+			id: XML.getAttribute(it as Tag, 'r:id'),
+			path: '',
+			data: ''
+		}))!
+		for (const sheetItem of sheetsList) {
+			const rels = (sheetsRelations.childs as Array<Tag>)
+			const rel = rels.find((it) => XML.getAttribute(it, 'Id') === sheetItem.id)
+			sheetItem.path = XML.getAttribute(rel!, 'Target')!
+		}
+
+		await Promise.all(sheetsList.map(async (it) => {
+			it.data = await this.parseWorkSheet(shared, zip.readAsText(`xl/${it.path}`))
+			return it
+		}))
+
+		return objectRemap(sheetsList, (v) => ({
+			key: v.name,
+			value: v.data
+		}))
+	}
+	public static async parseWorkSheet(refs: Tag, data: string): Promise<string> {
+		const json = await XML.parse(data)
+		const sheetData = XML.findChild(json, 'sheetData')!
+		let headers: Array<string> = []
+		const res: Array<Record<string, any>> = []
+		let headerDone = false
+		for (const row of sheetData.childs ?? []) {
+			const line: Array<string> = []
+			const id = XML.getAttribute((row as Tag), 'r')
+			for (const col of (row as Tag).childs ?? []) {
+				if (!(col as Tag).childs) {
+					continue
+				}
+				const type = XML.getAttribute(col as Tag, 't')
+				const colIdx = XML.getAttribute(col as Tag, 'r')
+				const idx = colIdx!.charCodeAt(0) - 65 // TODO: handle more than 26 cols
+				const value = XML.findChild(col as Tag, 'v')?.childs?.[0]
+				if (!value || typeof value !== 'string') {
+					continue
+				}
+				// const value = ((col as Tag).childs![0] as Tag).childs![0] as string
+				if (type === 's') {
+					line[idx] = this.getRef(refs, value)
+				} else {
+					line[idx] = value
+				}
+			}
+
+			if (!headerDone) {
+				headers = line
+			} else {
+				res[parseInt(id!, 10) - 1] = objectRemap(line, (v, idx: number) => {
+					return {
+						key: headers[idx] as string,
+						value: v
+					}
+				})
+			}
+
+
+			headerDone = true
+		}
+
+		return CSV.stringify(headers, res)
+	}
+
+	private static getRef(refs: Tag, id: string | number): string {
+		if (typeof id === 'string') {
+			id = parseInt(id, 10)
+		}
+
+		return ((refs.childs![id] as Tag)!.childs![0] as Tag)!.childs![0] as string
+	}
+}