// credits: https://github.com/fabiospampinato/plain-object-is-equal
// vendored here because of esm issues

/* HELPERS */

const getKeys = Object.keys
// const hasOwnProperty = Object.prototype.hasOwnProperty
const isArray = Array.isArray

/* MAIN */

const isEqual = (x: any, y: any): boolean => {
  if (x === y) return true

  if (typeof x === 'object' && typeof y === 'object' && x !== null && y !== null) {
    if (x.constructor !== y.constructor) return false

    if (x instanceof Map || x instanceof Set) x = [...x]
    if (y instanceof Map || y instanceof Set) y = [...y]

    if (isArray(x)) {
      if (isArray(y)) {
        let xLength = x.length
        const yLength = y.length

        if (xLength !== yLength) return false

        while (xLength--) {
          if (!isEqual(x[xLength], y[xLength])) return false
        }

        return true
      }

      return false
    } else if (isArray(y)) {
      return false
    } else {
      const xKeys = getKeys(x)
      let xLength = xKeys.length
      const yKeys = getKeys(y)
      const yLength = yKeys.length

      if (xLength !== yLength) return false

      while (xLength--) {
        const key = xKeys[xLength]
        const xValue = x[key]
        const yValue = y[key]

        if (!isEqual(xValue, yValue)) return false

        if (yValue === undefined && !Object.hasOwn(y, key)) return false
      }
    }

    return true
  }

  return x !== x && y !== y
}

/* EXPORT */

export default isEqual