const-utils.ts

import * as Option from 'fp-ts/lib/Option'
import { pipe } from 'fp-ts/lib/function'

import { operators, builtinFunctions } from './constants'
import { Operator, SqlFunction, NullSafety } from './types'

export function findOperator(name: string): Option.Option<Operator> {
  const upCaseName = name.toUpperCase()
  return Option.fromNullable(operators.find((op) => op.op === upCaseName))
}

export function isOperatorCommutative(name: string): boolean {
  return pipe(
    findOperator(name),
    Option.map((op) => op.commutative || false),
    Option.getOrElse<boolean>(() => false)
  )
}

export function operatorNullSafety(name: string): NullSafety | null {
  return pipe(
    findOperator(name),
    Option.map((op) => op.nullSafety),
    Option.toNullable
  )
}

export function findBuiltinFunction(name: string): Option.Option<SqlFunction> {
  const downCaseName = name.toLowerCase()
  return Option.fromNullable(
    builtinFunctions.find((f) => f.name === downCaseName)
  )
}

export function builtinFunctionNullSafety(name: string): NullSafety | null {
  return pipe(
    findBuiltinFunction(name),
    Option.map((func) => func.nullSafety),
    Option.toNullable
  )
}