github.com/kaydxh/golang@v0.0.131/go/container/set/set.go

/*
 *Copyright (c) 2022, kaydxh
 *
 *Permission is hereby granted, free of charge, to any person obtaining a copy
 *of this software and associated documentation files (the "Software"), to deal
 *in the Software without restriction, including without limitation the rights
 *to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 *copies of the Software, and to permit persons to whom the Software is
 *furnished to do so, subject to the following conditions:
 *
 *The above copyright notice and this permission notice shall be included in all
 *copies or substantial portions of the Software.
 *
 *THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 *IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 *FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 *AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 *LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 *OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 *SOFTWARE.
 */
package set

import (
	"encoding/json"
	"sort"
)

// type Set[type T comparable] map[T]Empty
type Set[T comparable] map[T]Empty

func New[T comparable](items ...T) Set[T] {
	// func New[T comparable]() Set[T] {
	ss := make(Set[T], len(items))
	ss.Insert(items...)
	return ss
}

// Insert adds items to the set.
func (s Set[T]) Insert(items ...T) Set[T] {
	for _, item := range items {
		s[item] = Empty{}
	}

	return s
}

// Delete removes all items from the set.
func (s Set[T]) Delete(items ...T) Set[T] {
	for _, item := range items {
		delete(s, item)
	}
	return s
}

// Has returns true if and only if item is contained in the set.
func (s Set[T]) Has(item T) bool {
	_, contained := s[item]
	return contained
}

// HasAll returns true if and only if all items are contained in the set.
func (s Set[T]) HasAll(items ...T) bool {
	for _, item := range items {
		if !s.Has(item) {
			return false
		}
	}
	return true
}

// HasAny returns true if any items are contained in the set.
func (s Set[T]) HasAny(items ...T) bool {
	for _, item := range items {
		if s.Has(item) {
			return true
		}
	}
	return false
}

// Difference returns a set of objects that are not in s2
// For example:
// s1 = {a1, a2, a3}
// s2 = {a1, a2, a4, a5}
// s1.Difference(s2) = {a3}
// s2.Difference(s1) = {a4, a5}
func (s Set[T]) Difference(s2 Set[T]) Set[T] {
	result := New[T]()
	for key := range s {
		if !s2.Has(key) {
			result.Insert(key)
		}
	}
	return result
}

// Union returns a new set which includes items in either s1 or s2.
// For example:
// s1 = {a1, a2}
// s2 = {a3, a4}
// s1.Union(s2) = {a1, a2, a3, a4}
// s2.Union(s1) = {a1, a2, a3, a4}
func (s1 Set[T]) Union(s2 Set[T]) Set[T] {
	result := New[T]()
	for key := range s1 {
		result.Insert(key)
	}
	for key := range s2 {
		result.Insert(key)
	}
	return result
}

// Intersection returns a new set which includes the item in BOTH s1 and s2
// For example:
// s1 = {a1, a2}
// s2 = {a2, a3}
// s1.Intersection(s2) = {a2}
func (s1 Set[T]) Intersection(s2 Set[T]) Set[T] {
	var walk, other Set[T]
	result := New[T]()
	if s1.Len() < s2.Len() {
		walk = s1
		other = s2
	} else {
		walk = s2
		other = s1
	}
	for key := range walk {
		if other.Has(key) {
			result.Insert(key)
		}
	}
	return result
}

// IsSuperset returns true if and only if s1 is a superset of s2.
func (s1 Set[T]) IsSuperset(s2 Set[T]) bool {
	for item := range s2 {
		if !s1.Has(item) {
			return false
		}
	}
	return true
}

// Equal returns true if and only if s1 is equal (as a set) to s2.
// Two sets are equal if their membership is identical.
// (In practice, this means same elements, order doesn't matter)
func (s1 Set[T]) Equal(s2 Set[T]) bool {
	return len(s1) == len(s2) && s1.IsSuperset(s2)
}

type sortableSliceOfT[T comparable] []T

func (s sortableSliceOfT[T]) Len() int           { return len(s) }
func (s sortableSliceOfT[T]) Less(i, j int) bool { return lessT(s[i], s[j]) }
func (s sortableSliceOfT[T]) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }

// List returns the contents as a sorted Object slice.
func (s Set[T]) List() []T {
	res := make(sortableSliceOfT[T], 0, len(s))
	for key := range s {
		res = append(res, key)
	}
	sort.Sort(res)
	return []T(res)
}

// UnsortedList returns the slice with contents in random order.
func (s Set[T]) UnsortedList() []T {
	res := make([]T, 0, len(s))
	for key := range s {
		res = append(res, key)
	}
	return res
}

// Returns a single element from the set.
func (s Set[T]) PopAny() (T, bool) {
	for key := range s {
		s.Delete(key)
		return key, true
	}
	var zeroValue T
	return zeroValue, false
}

// Len returns the size of the set.
func (s Set[T]) Len() int {
	return len(s)
}

type LesserT[T comparable] interface {
	Less(a, b T) bool
}

func lessT[T comparable](lhs, rhs T) bool {
	jbl, err := json.Marshal(lhs)
	if err != nil {
		return false
	}
	jbr, err := json.Marshal(rhs)
	if err != nil {
		return false
	}

	return string(jbl) < string(jbr)
}