import type {Bud} from '@roots/bud-framework'

import {BudError} from '@roots/bud-support/errors'
import isArray from '@roots/bud-support/isArray'
import isFunction from '@roots/bud-support/isFunction'
import noop from '@roots/bud-support/noop'

export interface when {
  (
    test:
      | ((app: Bud) => boolean)
      | Array<((app: Bud) => boolean) | boolean>
      | boolean,
    trueCase: ((app: Bud) => any) | Array<(app: Bud) => any>,
    falseCase?: ((app: Bud) => any) | Array<(app: Bud) => any>,
  ): Bud
}

/**
 * Executes a function if a given test is true
 *
 * @remarks
 * - The first parameter is the conditional check.
 * - The second parameter is the function to run if true.
 * - The third parameter is optional; executed if the conditional is not true.
 *
 * @example
 * Only produce a vendor bundle when running in `production`:
 *
 * ```js
 * bud.when(bud.isProduction, () => bud.vendor())
 * ```
 *
 * @example
 * Use `eval` sourcemap in development mode and `hidden-source-map` in production:
 *
 * ```js
 * bud.when(
 *   bud.isDevelopment,
 *   () => bud.devtool('eval'),
 *   () => bud.devtool('hidden-source-map'),
 * )
 * ```
 */
export function when(
  test:
    | ((app: Bud) => boolean)
    | Array<((app: Bud) => boolean) | boolean>
    | boolean,
  trueCase: ((app: Bud) => any) | Array<(app: Bud) => any>,
  falseCase?: ((app: Bud) => any) | Array<(app: Bud) => any>,
): Bud {
  const callTestCase = (value: any) => {
    const iterableValue = isArray(value) ? value : [value]
    return iterableValue.every(v => this.maybeCall(v) === true)
  }

  const whenTrue = isArray(trueCase) ? trueCase : [trueCase ?? noop]
  const whenFalse = isArray(falseCase) ? falseCase : [falseCase ?? noop]

  /* validate */
  if (![...whenTrue, ...whenFalse].every(isFunction)) {
    throw BudError.normalize(
      `bud.when: all supplied conditionals must be functions`,
      {
        docs: new URL(`https://bud.js.org/docs/bud.when`),
      },
    )
  }

  callTestCase(test) ? whenTrue.map(this.tap) : whenFalse.map(this.tap)

  return this
}