quran-meta/src/getJuzMeta.ts

Library with meta data and functionality related to Holy Quran

import { findSurahAyahByAyahId } from "./findSurahAyahByAyahId"
import type { RiwayaData } from "./lists/types"
import type { AyahId, Juz, JuzMeta } from "./types"
import { checkValidJuz } from "./validation"

/**
 * Retrieves metadata for a specific Juz of the Quran.
 *
 * @param juzNum - The Juz number to retrieve metadata for (1-30)
 * @param data - The Lists object for the riwaya.
 * @returns An object containing the Juz number, first ayah, and last ayah in the Juz
 * @throws RangeError If the Juz number is not between 1 and 30
 */
export function getJuzMeta(
  juzNum: Juz,
  data: RiwayaData
): JuzMeta {
  checkValidJuz(juzNum, data.meta)
  const JuzList = data.JuzList
  const [firstAyahId, nextJuzAyahId]: [AyahId, AyahId] = [
    JuzList[juzNum],
    JuzList[juzNum + 1]
  ]
  const lastAyahId = nextJuzAyahId - 1
  return {
    juzNum,
    firstAyahId,
    lastAyahId,
    first: findSurahAyahByAyahId(firstAyahId, data),
    last: findSurahAyahByAyahId(lastAyahId, data)
  }
}