package channel

import "container/list"

// ToSlice returns a slice containing all values read from ch
func ToSlice[T any](ch <-chan T) []T {
	s := make([]T, 0, cap(ch))
	Each(ch, func(value T) { s = append(s, value) })
	return s
}

// ToSliceDeref returns a slice containing all values read from ch.
// The returned slice will be a dereferenced and continuous block of memory.
// Nil pointers are ignored.
func ToSliceDeref[T any](ch <-chan *T) []T {
	s := make([]T, 0, cap(ch))
	Each(ch, func(value *T) {
		if value != nil {
			s = append(s, *value)
		}
	})
	return s
}

// ToList returns a list.List containing all values read from ch
func ToList[T any](ch <-chan T) *list.List {
	l := list.New()
	Each(ch, func(value T) { l.PushBack(value) })
	return l
}

// ToMap returns a map containing all values read from ch.
// The map keys are determined by f
func ToMap[K comparable, V any](ch <-chan V, f func(V) K) map[K]V {
	m := map[K]V{}
	Each(ch, func(value V) { m[f(value)] = value })
	return m
}

// ToKeyMap returns a map containing all values read from ch as keys.
// The map values are determined by f
func ToKeyMap[K comparable, V any](ch <-chan K, f func(K) V) map[K]V {
	m := map[K]V{}
	Each(ch, func(key K) { m[key] = f(key) })
	return m
}

// ToStructMap returns a struct{} map containing all values read from ch as keys.
// It is a shorthand for ToKeyMap(ch, func(k K) struct{} { return struct{}{} })
func ToStructMap[T comparable](ch <-chan T) map[T]struct{} {
	return ToKeyMap(ch, func(key T) struct{} { return struct{}{} })
}