import { constant, flow } from 'fp-ts/es6/function';
import * as O from 'fp-ts/es6/Option';
import { pipe } from 'fp-ts/es6/pipeable';
import * as _ from './internal';
// -------------------------------------------------------------------------------------
// constructors
// -------------------------------------------------------------------------------------
/**
 * @category constructors
 * @since 2.3.8
 */
export var optional = _.optional;
/**
 * @category constructors
 * @since 2.3.0
 */
export var id = function () { return optional(O.some, constant); };
// -------------------------------------------------------------------------------------
// converters
// -------------------------------------------------------------------------------------
/**
 * View a `Optional` as a `Traversal`.
 *
 * @category converters
 * @since 2.3.0
 */
export var asTraversal = _.optionalAsTraversal;
// -------------------------------------------------------------------------------------
// compositions
// -------------------------------------------------------------------------------------
/**
 * Compose a `Optional` with a `Optional`.
 *
 * @category compositions
 * @since 2.3.0
 */
export var compose = _.optionalComposeOptional;
/**
 * Alias of `compose`.
 *
 * @category compositions
 * @since 2.3.8
 */
export var composeOptional = compose;
/**
 * Compose a `Optional` with a `Iso`.
 *
 * @category compositions
 * @since 2.3.8
 */
export var composeIso = 
/*#__PURE__*/
flow(_.isoAsOptional, compose);
/**
 * Compose a `Optional` with a `Lens`.
 *
 * @category compositions
 * @since 2.3.7
 */
export var composeLens = 
/*#__PURE__*/
flow(_.lensAsOptional, _.optionalComposeOptional);
/**
 * Compose a `Optional` with a `Prism`.
 *
 * @category compositions
 * @since 2.3.7
 */
export var composePrism = 
/*#__PURE__*/
flow(_.prismAsOptional, _.optionalComposeOptional);
/**
 * Compose a `Optional` with an `Traversal`.
 *
 * @category compositions
 * @since 2.3.8
 */
export var composeTraversal = function (ab) {
    return flow(asTraversal, _.traversalComposeTraversal(ab));
};
// -------------------------------------------------------------------------------------
// combinators
// -------------------------------------------------------------------------------------
/**
 * @category combinators
 * @since 2.3.0
 */
export var modifyOption = _.optionalModifyOption;
/**
 * @category combinators
 * @since 2.3.7
 */
export var setOption = function (a) { return modifyOption(function () { return a; }); };
/**
 * @category combinators
 * @since 2.3.0
 */
export var modify = _.optionalModify;
export function modifyF(F) {
    return function (f) { return function (sa) { return function (s) {
        return pipe(sa.getOption(s), O.fold(function () { return F.of(s); }, function (a) { return F.map(f(a), function (a) { return sa.set(a)(s); }); }));
    }; }; };
}
/**
 * Return an `Optional` from a `Optional` focused on a nullable value.
 *
 * @category combinators
 * @since 2.3.3
 */
export var fromNullable = 
/*#__PURE__*/
compose(/*#__PURE__*/ _.prismAsOptional(/*#__PURE__*/ _.prismFromNullable()));
export function filter(predicate) {
    return compose(_.prismAsOptional(_.prismFromPredicate(predicate)));
}
/**
 * Return a `Optional` from a `Optional` and a prop.
 *
 * @category combinators
 * @since 2.3.0
 */
export var prop = function (prop) {
    return compose(pipe(_.lensId(), _.lensProp(prop), _.lensAsOptional));
};
/**
 * Return a `Optional` from a `Optional` and a list of props.
 *
 * @category combinators
 * @since 2.3.0
 */
export var props = function () {
    var props = [];
    for (var _i = 0; _i < arguments.length; _i++) {
        props[_i] = arguments[_i];
    }
    return compose(pipe(_.lensId(), _.lensProps.apply(_, props), _.lensAsOptional));
};
/**
 * Return a `Optional` from a `Optional` focused on a component of a tuple.
 *
 * @category combinators
 * @since 2.3.0
 */
export var component = function (prop) {
    return compose(pipe(_.lensId(), _.lensComponent(prop), _.lensAsOptional));
};
/**
 * Return a `Optional` from a `Optional` focused on an index of a `ReadonlyArray`.
 *
 * @category combinators
 * @since 2.3.0
 */
export var index = _.optionalIndex;
/**
 * Return a `Optional` from a `Optional` focused on an index of a `ReadonlyNonEmptyArray`.
 *
 * @category combinators
 * @since 2.3.8
 */
export var indexNonEmpty = _.optionalIndexNonEmpty;
/**
 * Return a `Optional` from a `Optional` focused on a key of a `ReadonlyRecord`.
 *
 * @category combinators
 * @since 2.3.0
 */
export var key = _.optionalKey;
/**
 * Return a `Optional` from a `Optional` focused on a required key of a `ReadonlyRecord`.
 *
 * @category combinators
 * @since 2.3.0
 */
export var atKey = function (key) { return function (sa) {
    return pipe(sa, compose(_.lensAsOptional(_.atReadonlyRecord().at(key))));
}; };
/**
 * Return a `Optional` from a `Optional` focused on the `Some` of a `Option` type.
 *
 * @category combinators
 * @since 2.3.0
 */
export var some = 
/*#__PURE__*/
compose(/*#__PURE__*/ _.prismAsOptional(/*#__PURE__*/ _.prismSome()));
/**
 * Return a `Optional` from a `Optional` focused on the `Right` of a `Either` type.
 *
 * @category combinators
 * @since 2.3.0
 */
export var right = 
/*#__PURE__*/
compose(/*#__PURE__*/ _.prismAsOptional(/*#__PURE__*/ _.prismRight()));
/**
 * Return a `Optional` from a `Optional` focused on the `Left` of a `Either` type.
 *
 * @category combinators
 * @since 2.3.0
 */
export var left = 
/*#__PURE__*/
compose(/*#__PURE__*/ _.prismAsOptional(/*#__PURE__*/ _.prismLeft()));
/**
 * Return a `Traversal` from a `Optional` focused on a `Traversable`.
 *
 * @category combinators
 * @since 2.3.0
 */
export function traverse(T) {
    return flow(asTraversal, _.traversalTraverse(T));
}
export function findFirst(predicate) {
    return compose(_.optionalFindFirst(predicate));
}
export function findFirstNonEmpty(predicate) {
    return compose(_.optionalFindFirstNonEmpty(predicate));
}
// -------------------------------------------------------------------------------------
// pipeables
// -------------------------------------------------------------------------------------
/**
 * @category Invariant
 * @since 2.3.0
 */
export var imap = function (f, g) { return function (ea) { return imap_(ea, f, g); }; };
// -------------------------------------------------------------------------------------
// instances
// -------------------------------------------------------------------------------------
var imap_ = function (ea, ab, ba) { return optional(flow(ea.getOption, O.map(ab)), flow(ba, ea.set)); };
/**
 * @category instances
 * @since 2.3.0
 */
export var URI = 'monocle-ts/Optional';
/**
 * @category instances
 * @since 2.3.0
 */
export var Invariant = {
    URI: URI,
    imap: imap_
};
/**
 * @category instances
 * @since 2.3.8
 */
export var Semigroupoid = {
    URI: URI,
    compose: function (ab, ea) { return compose(ab)(ea); }
};
/**
 * @category instances
 * @since 2.3.0
 */
export var Category = {
    URI: URI,
    compose: Semigroupoid.compose,
    id: id
};