/**
 * This module provides types and utility functions to create and work with branded types,
 * which are TypeScript types with an added type tag to prevent accidental usage of a value in the wrong context.
 *
 * The `refined` and `nominal` functions are both used to create branded types in TypeScript.
 * The main difference between them is that `refined` allows for validation of the data, while `nominal` does not.
 *
 * The `nominal` function is used to create a new branded type that has the same underlying type as the input, but with a different name.
 * This is useful when you want to distinguish between two values of the same type that have different meanings.
 * The `nominal` function does not perform any validation of the input data.
 *
 * On the other hand, the `refined` function is used to create a new branded type that has the same underlying type as the input,
 * but with a different name, and it also allows for validation of the input data.
 * The `refined` function takes a predicate that is used to validate the input data.
 * If the input data fails the validation, a `BrandErrors` is returned, which provides information about the specific validation failure.
 *
 * @since 1.0.0
 */
import * as Either from "@effect/data/Either"
import { identity } from "@effect/data/Function"
import * as Option from "@effect/data/Option"
import type { Predicate, Refinement } from "@effect/data/Predicate"
import * as ReadonlyArray from "@effect/data/ReadonlyArray"
import type * as Types from "@effect/data/Types"

/**
 * @since 1.0.0
 * @category symbols
 */
export const BrandTypeId: unique symbol = Symbol.for("@effect/data/Brand")

/**
 * @since 1.0.0
 * @category symbols
 */
export type BrandTypeId = typeof BrandTypeId

/**
 * @since 1.0.0
 * @category symbols
 */
export const RefinedConstructorsTypeId: unique symbol = Symbol.for("@effect/data/Brand/Refined")

/**
 * @since 1.0.0
 * @category symbols
 */
export type RefinedConstructorsTypeId = typeof RefinedConstructorsTypeId

/**
 * A generic interface that defines a branded type.
 *
 * @since 1.0.0
 * @category models
 */
export interface Brand<in out K extends string | symbol> {
  readonly [BrandTypeId]: {
    readonly [k in K]: K
  }
}

/**
 * @since 1.0.0
 */
export declare namespace Brand {
  /**
   * Represents a list of refinement errors.
   *
   * @since 1.0.0
   * @category models
   */
  export interface BrandErrors extends ReadonlyArray<RefinementError> {}

  /**
   * Represents an error that occurs when the provided value of the branded type does not pass the refinement predicate.
   *
   * @since 1.0.0
   * @category models
   */
  export interface RefinementError {
    readonly meta: unknown
    readonly message: string
  }

  /**
   * @since 1.0.0
   * @category models
   */
  export interface Constructor<in out A extends Brand<any>> {
    readonly [RefinedConstructorsTypeId]: RefinedConstructorsTypeId
    /**
     * Constructs a branded type from a value of type `A`, throwing an error if
     * the provided `A` is not valid.
     */
    (args: Brand.Unbranded<A>): A
    /**
     * Constructs a branded type from a value of type `A`, returning `Some<A>`
     * if the provided `A` is valid, `None` otherwise.
     */
    option: (args: Brand.Unbranded<A>) => Option.Option<A>
    /**
     * Constructs a branded type from a value of type `A`, returning `Right<A>`
     * if the provided `A` is valid, `Left<BrandError>` otherwise.
     */
    either: (args: Brand.Unbranded<A>) => Either.Either<Brand.BrandErrors, A>
    /**
     * Attempts to refine the provided value of type `A`, returning `true` if
     * the provided `A` is valid, `false` otherwise.
     */
    is: Refinement<Brand.Unbranded<A>, Brand.Unbranded<A> & A>
  }

  /**
   * A utility type to extract a branded type from a `Brand.Constructor`.
   *
   * @since 1.0.0
   * @category models
   */
  export type FromConstructor<A> = A extends Brand.Constructor<infer B> ? B : never

  /**
   * A utility type to extract the value type from a brand.
   *
   * @since 1.0.0
   * @category models
   */
  export type Unbranded<P> = P extends infer Q & Brands<P> ? Q : P

  /**
   * A utility type to extract the brands from a branded type.
   *
   * @since 1.0.0
   * @category models
   */
  export type Brands<P> = P extends Brand<any> ? Types.UnionToIntersection<
      {
        [k in keyof P[BrandTypeId]]: k extends string | symbol ? Brand<k>
          : never
      }[keyof P[BrandTypeId]]
    >
    : never

  /**
   * A utility type that checks that all brands have the same base type.
   *
   * @since 1.0.0
   * @category models
   */
  export type EnsureCommonBase<
    Brands extends readonly [Brand.Constructor<any>, ...Array<Brand.Constructor<any>>]
  > = {
    [B in keyof Brands]: Brand.Unbranded<Brand.FromConstructor<Brands[0]>> extends
      Brand.Unbranded<Brand.FromConstructor<Brands[B]>>
      ? Brand.Unbranded<Brand.FromConstructor<Brands[B]>> extends Brand.Unbranded<Brand.FromConstructor<Brands[0]>>
        ? Brands[B]
      : Brands[B]
      : "ERROR: All brands should have the same base type"
  }
}

/**
 * @category alias
 * @since 1.0.0
 */
export type Branded<A, K extends string | symbol> = A & Brand<K>

/**
 * Returns a `BrandErrors` that contains a single `RefinementError`.
 *
 * @since 1.0.0
 * @category constructors
 */
export const error: (message: string, meta?: unknown) => Brand.BrandErrors = (
  message: string,
  meta?: unknown
): Brand.BrandErrors => [{
  message,
  meta
}]

/**
 * Takes a variable number of `BrandErrors` and returns a single `BrandErrors` that contains all refinement errors.
 *
 * @since 1.0.0
 * @category constructors
 */
export const errors: (...errors: Array<Brand.BrandErrors>) => Brand.BrandErrors = (
  ...errors: Array<Brand.BrandErrors>
): Brand.BrandErrors => ReadonlyArray.flatten(errors)

/**
 * Returns a `Brand.Constructor` that can construct a branded type from an unbranded value using the provided `refinement`
 * predicate as validation of the input data.
 *
 * If you don't want to perform any validation but only distinguish between two values of the same type but with different meanings,
 * see {@link nominal}.
 *
 * @param refinement - The refinement predicate to apply to the unbranded value.
 * @param onFailure - Takes the unbranded value that did not pass the `refinement` predicate and returns a `BrandErrors`.
 *
 * @example
 * import * as Brand from "@effect/data/Brand"
 *
 * type Int = number & Brand.Brand<"Int">
 *
 * const Int = Brand.refined<Int>(
 *   (n) => Number.isInteger(n),
 *   (n) => Brand.error(`Expected ${n} to be an integer`)
 * )
 *
 * assert.strictEqual(Int(1), 1)
 * assert.throws(() => Int(1.1))
 *
 * @since 1.0.0
 * @category constructors
 */
export const refined: <A extends Brand<any>>(
  refinement: Predicate<Brand.Unbranded<A>>,
  onFailure: (a: Brand.Unbranded<A>) => Brand.BrandErrors
) => Brand.Constructor<A> = <A extends Brand<any>>(
  refinement: Predicate<Brand.Unbranded<A>>,
  onFailure: (a: Brand.Unbranded<A>) => Brand.BrandErrors
): Brand.Constructor<A> => {
  const either = (args: Brand.Unbranded<A>): Either.Either<Brand.BrandErrors, A> =>
    refinement(args) ? Either.right(args as A) : Either.left(onFailure(args))
  // @ts-expect-error
  return Object.assign((args) =>
    Either.match(either(args), {
      onLeft: (e) => {
        throw e
      },
      onRight: identity
    }), {
    [RefinedConstructorsTypeId]: RefinedConstructorsTypeId,
    option: (args: any) => Option.getRight(either(args)),
    either,
    is: (args: any): args is Brand.Unbranded<A> & A => Either.isRight(either(args))
  })
}

/**
 * This function returns a `Brand.Constructor` that **does not apply any runtime checks**, it just returns the provided value.
 * It can be used to create nominal types that allow distinguishing between two values of the same type but with different meanings.
 *
 * If you also want to perform some validation, see {@link refined}.
 *
 * @example
 * import * as Brand from "@effect/data/Brand"
 *
 * type UserId = number & Brand.Brand<"UserId">
 *
 * const UserId = Brand.nominal<UserId>()
 *
 * assert.strictEqual(UserId(1), 1)
 *
 * @since 1.0.0
 * @category constructors
 */
export const nominal: <A extends Brand<any>>() => Brand.Constructor<A> = <A extends Brand<any>>(): Brand.Constructor<
  A
> => {
  // @ts-expect-error
  return Object.assign((args) => args, {
    [RefinedConstructorsTypeId]: RefinedConstructorsTypeId,
    option: (args: any) => Option.some(args),
    either: (args: any) => Either.right(args),
    is: (_args: any): _args is Brand.Unbranded<A> & A => true
  })
}

/**
 * Combines two or more brands together to form a single branded type.
 * This API is useful when you want to validate that the input data passes multiple brand validators.
 *
 * @example
 * import * as Brand from "@effect/data/Brand"
 *
 * type Int = number & Brand.Brand<"Int">
 * const Int = Brand.refined<Int>(
 *   (n) => Number.isInteger(n),
 *   (n) => Brand.error(`Expected ${n} to be an integer`)
 * )
 * type Positive = number & Brand.Brand<"Positive">
 * const Positive = Brand.refined<Positive>(
 *   (n) => n > 0,
 *   (n) => Brand.error(`Expected ${n} to be positive`)
 * )
 *
 * const PositiveInt = Brand.all(Int, Positive)
 *
 * assert.strictEqual(PositiveInt(1), 1)
 * assert.throws(() => PositiveInt(1.1))
 *
 * @since 1.0.0
 * @category combining
 */
export const all: <Brands extends readonly [Brand.Constructor<any>, ...Array<Brand.Constructor<any>>]>(
  ...brands: Brand.EnsureCommonBase<Brands>
) => Brand.Constructor<
  Types.UnionToIntersection<{ [B in keyof Brands]: Brand.FromConstructor<Brands[B]> }[number]> extends
    infer X extends Brand<any> ? X : Brand<any>
> = <
  Brands extends readonly [Brand.Constructor<any>, ...Array<Brand.Constructor<any>>]
>(...brands: Brand.EnsureCommonBase<Brands>): Brand.Constructor<
  Types.UnionToIntersection<
    {
      [B in keyof Brands]: Brand.FromConstructor<Brands[B]>
    }[number]
  > extends infer X extends Brand<any> ? X : Brand<any>
> => {
  const either = (args: any): Either.Either<Brand.BrandErrors, any> => {
    let result: Either.Either<Brand.BrandErrors, any> = Either.right(args)
    for (const brand of brands) {
      const nextResult = brand.either(args)
      if (Either.isLeft(result) && Either.isLeft(nextResult)) {
        result = Either.left([...result.left, ...nextResult.left])
      } else {
        result = Either.isLeft(result) ? result : nextResult
      }
    }
    return result
  }
  // @ts-expect-error
  return Object.assign((args) =>
    Either.match(either(args), {
      onLeft: (e) => {
        throw e
      },
      onRight: identity
    }), {
    [RefinedConstructorsTypeId]: RefinedConstructorsTypeId,
    option: (args: any) => Option.getRight(either(args)),
    either,
    is: (args: any): args is any => Either.isRight(either(args))
  })
}