// Copyright (c) 2023 IBM Corp.
// All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package generic

import (
	F "github.com/IBM/fp-go/function"
	M "github.com/IBM/fp-go/monoid"
	S "github.com/IBM/fp-go/semigroup"
)

func UnionMonoid[N ~map[K]V, K comparable, V any](s S.Semigroup[V]) M.Monoid[N] {
	return M.MakeMonoid(
		UnionSemigroup[N](s).Concat,
		Empty[N](),
	)
}

func UnionLastMonoid[N ~map[K]V, K comparable, V any]() M.Monoid[N] {
	return M.MakeMonoid(
		unionLast[N],
		Empty[N](),
	)
}

func UnionFirstMonoid[N ~map[K]V, K comparable, V any]() M.Monoid[N] {
	return M.MakeMonoid(
		F.Swap(unionLast[N]),
		Empty[N](),
	)
}