// Copyright (C) 2022-2023  Luke Shumaker <lukeshu@lukeshu.com>
//
// SPDX-License-Identifier: GPL-2.0-or-later

package typedsync

import (
	"sync"
)

// Map is a type-safe equivalent of the standard library's sync.Map.
//
// See the [sync.Map documentation] for full details.
//
// Go 1.20 added sync.Map.Swap method; this method is only available
// on typedsync.Map if built with Go 1.20 or later.
//
// Go 1.20 added sync.Map.CompareAndDelete and sync.Map.CompareAndSwap
// methods that are only usable if V is a comparable type; these
// methods are not available on typedsync.Map, but when typedsync is
// built with Go 1.20 or later they are available on a separate
// ComparableMap type.
//
// When typedsync is built versions of Go prior to Go 1.20,
// typedsync.Map is specified too loosely, as
//
//	Map[K any, V any]
//
// while with Go 1.20 and later, typedsync.Map is specified as
//
//	Map[K comparable, V any]
//
// This is because with Go versions prior to 1.20, 'comparable' was
// overly strict, disallowing many types that are valid map-keys (see
// https://github.com/golang/go/issues/56548).  The type used as K in
// a Map with older versions of Go must be a valid map-key type, even
// though the type specification of Map does not enforce that.
//
// [sync.Map documentation]: https://pkg.go.dev/sync#Map
type Map[K mapkey, V any] struct {
	inner sync.Map
}

func (m *Map[K, V]) Delete(key K) {
	m.inner.Delete(key)
}

func (m *Map[K, V]) Load(key K) (value V, ok bool) {
	_value, ok := m.inner.Load(key)
	if ok {
		//nolint:forcetypeassert // Typed wrapper around untyped lib.
		value = _value.(V)
	}
	return value, ok
}

func (m *Map[K, V]) LoadAndDelete(key K) (value V, loaded bool) {
	_value, ok := m.inner.LoadAndDelete(key)
	if ok {
		//nolint:forcetypeassert // Typed wrapper around untyped lib.
		value = _value.(V)
	}
	return value, ok
}

func (m *Map[K, V]) LoadOrStore(key K, value V) (actual V, loaded bool) {
	_actual, loaded := m.inner.LoadOrStore(key, value)
	//nolint:forcetypeassert // Typed wrapper around untyped lib.
	actual = _actual.(V)
	return actual, loaded
}

func (m *Map[K, V]) Range(f func(key K, value V) bool) {
	m.inner.Range(func(key, value any) bool {
		//nolint:forcetypeassert // Typed wrapper around untyped lib.
		return f(key.(K), value.(V))
	})
}

func (m *Map[K, V]) Store(key K, value V) {
	m.inner.Store(key, value)
}