slice.go

package g

import (
	"fmt"
	"reflect"
	"slices"
	"strings"

	"github.com/enetx/g/cmp"
	"github.com/enetx/g/f"
	"github.com/enetx/g/pkg/rand"
)

// NewSlice creates a new Slice of the given generic type T with the specified length and
// capacity.
// The size variadic parameter can have zero, one, or two integer values.
// If no values are provided, an empty Slice with a length and capacity of 0 is returned.
// If one value is provided, it sets both the length and capacity of the Slice.
// If two values are provided, the first value sets the length and the second value sets the
// capacity.
//
// Parameters:
//
// - size ...Int: A variadic parameter specifying the length and/or capacity of the Slice
//
// Returns:
//
// - Slice[T]: A new Slice of the specified generic type T with the given length and capacity
//
// Example usage:
//
//	s1 := g.NewSlice[int]()        // Creates an empty Slice of type int
//	s2 := g.NewSlice[int](5)       // Creates an Slice with length and capacity of 5
//	s3 := g.NewSlice[int](3, 10)   // Creates an Slice with length of 3 and capacity of 10
func NewSlice[T any](size ...Int) Slice[T] {
	var (
		length   Int
		capacity Int
	)

	switch {
	case len(size) > 1:
		length, capacity = size[0], size[1]
	case len(size) == 1:
		length, capacity = size[0], size[0]
	}

	return make(Slice[T], length, capacity)
}

// SliceOf creates a new generic slice containing the provided elements.
func SliceOf[T any](slice ...T) Slice[T] { return slice }

// SliceMap applies the given function to each element of a Slice and returns a new Slice
// containing the transformed values.
//
// Parameters:
//
// - sl: The input Slice.
//
// - fn: The function to apply to each element of the input Slice.
//
// Returns:
//
// A new Slice containing the results of applying the function to each element of the input Slice.
func SliceMap[T, U any](sl Slice[T], fn func(T) U) Slice[U] { return sliceMap(sl.Iter(), fn).Collect() }

// Iter returns an iterator (SeqSlice[T]) for the Slice, allowing for sequential iteration
// over its elements. It is commonly used in combination with higher-order functions,
// such as 'ForEach', to perform operations on each element of the Slice.
//
// Returns:
//
// A SeqSlice[T], which can be used for sequential iteration over the elements of the Slice.
//
// Example usage:
//
//	slice := g.Slice[int]{1, 2, 3, 4, 5}
//	iterator := slice.Iter()
//	iterator.ForEach(func(element int) {
//		// Perform some operation on each element
//		fmt.Println(element)
//	})
//
// The 'Iter' method provides a convenient way to traverse the elements of a Slice
// in a functional style, enabling operations like mapping or filtering.
func (sl Slice[T]) Iter() SeqSlice[T] { return ToSeqSlice(sl) }

// AsAny converts each element of the slice to the 'any' type.
// It returns a new slice containing the elements as 'any' g.Slice[any].
//
// Note: AsAny is useful when you want to work with a slice of a specific type as a slice of 'any'.
// It can be particularly handy in conjunction with Flatten to work with nested slices of different types.
func (sl Slice[T]) AsAny() Slice[any] { return SliceMap(sl, func(t T) any { return any(t) }) }

// Fill fills the slice with the specified value.
// This function is useful when you want to create an Slice with all elements having the same
// value.
// This method modifies the original slice in place.
//
// Parameters:
//
// - val T: The value to fill the Slice with.
//
// Returns:
//
// - Slice[T]: A reference to the original Slice filled with the specified value.
//
// Example usage:
//
//	slice := g.Slice[int]{0, 0, 0}
//	slice.Fill(5)
//
// The modified slice will now contain: 5, 5, 5.
func (sl Slice[T]) Fill(val T) {
	for i := range sl {
		sl[i] = val
	}
}

// Index returns the index of the first occurrence of the specified value in the slice, or -1 if
// not found.
func (sl Slice[T]) Index(val T) Int {
	switch s := any(sl).(type) {
	case Slice[Int]:
		return Int(slices.Index(s, any(val).(Int)))
	case Slice[String]:
		return Int(slices.Index(s, any(val).(String)))
	case Slice[Float]:
		return Int(slices.Index(s, any(val).(Float)))
	case Slice[string]:
		return Int(slices.Index(s, any(val).(string)))
	case Slice[bool]:
		return Int(slices.Index(s, any(val).(bool)))
	case Slice[int]:
		return Int(slices.Index(s, any(val).(int)))
	case Slice[int8]:
		return Int(slices.Index(s, any(val).(int8)))
	case Slice[int16]:
		return Int(Int(slices.Index(s, any(val).(int16))))
	case Slice[int32]:
		return Int(slices.Index(s, any(val).(int32)))
	case Slice[int64]:
		return Int(slices.Index(s, any(val).(int64)))
	case Slice[uint]:
		return Int(slices.Index(s, any(val).(uint)))
	case Slice[uint8]:
		return Int(slices.Index(s, any(val).(uint8)))
	case Slice[uint16]:
		return Int(slices.Index(s, any(val).(uint16)))
	case Slice[uint32]:
		return Int(slices.Index(s, any(val).(uint32)))
	case Slice[uint64]:
		return Int(slices.Index(s, any(val).(uint64)))
	case Slice[float32]:
		return Int(slices.Index(s, any(val).(float32)))
	case Slice[float64]:
		return Int(slices.Index(s, any(val).(float64)))
	default:
		return sl.IndexBy(f.Eqd(val))
	}
}

// IndexBy returns the index of the first element in the slice
// satisfying the custom comparison function provided by the user.
// It iterates through the slice and applies the comparison function to each element and the target value.
// If the comparison function returns true for any pair of elements, it returns the index of that element.
// If no such element is found, it returns -1.
func (sl Slice[T]) IndexBy(fn func(t T) bool) Int { return Int(slices.IndexFunc(sl, fn)) }

// RandomSample returns a new slice containing a random sample of elements from the original slice.
// The sampling is done without replacement, meaning that each element can only appear once in the result.
//
// Parameters:
//
// - sequence int: The number of unique elements to include in the random sample.
//
// Returns:
//
// - Slice[T]: A new Slice containing the random sample of unique elements.
//
// Example usage:
//
//	slice := g.Slice[int]{1, 2, 3, 4, 5, 6, 7, 8, 9}
//	sample := slice.RandomSample(3)
//
// The resulting sample will contain 3 unique elements randomly selected from the original slice.
func (sl Slice[T]) RandomSample(sequence Int) Slice[T] {
	if sequence.Gte(sl.Len()) {
		return sl
	}

	clone := sl.Clone()
	clone.Shuffle()

	return clone[0:sequence]
}

// RandomRange returns a new slice containing a random sample of elements from a subrange of the original slice.
// The sampling is done without replacement, meaning that each element can only appear once in the result.
func (sl Slice[T]) RandomRange(from, to Int) Slice[T] {
	if from < 0 {
		from = 0
	}

	if to < 0 || to > sl.Len() {
		to = sl.Len()
	}

	if from > to {
		from = to
	}

	return sl.RandomSample(from.RandomRange(to))
}

// Insert inserts values at the specified index in the slice and returns the resulting slice.
// The original slice remains unchanged.
//
// Parameters:
//
// - i Int: The index at which to insert the new values.
//
// - values ...T: A variadic list of values to insert at the specified index.
//
// Returns:
//
// - Slice[T]: A new Slice containing the original elements and the inserted values.
//
// Example usage:
//
//	slice := g.Slice[string]{"a", "b", "c", "d"}
//	newSlice := slice.Insert(2, "e", "f")
//
// The resulting newSlice will be: ["a", "b", "e", "f", "c", "d"].
func (sl Slice[T]) Insert(i Int, values ...T) Slice[T] { return sl.Replace(i, i, values...) }

// InsertInPlace inserts values at the specified index in the slice and modifies the original
// slice.
//
// Parameters:
//
// - i Int: The index at which to insert the new values.
//
// - values ...T: A variadic list of values to insert at the specified index.
//
// Example usage:
//
//	slice := g.Slice[string]{"a", "b", "c", "d"}
//	slice.InsertInPlace(2, "e", "f")
//
// The resulting slice will be: ["a", "b", "e", "f", "c", "d"].
func (sl *Slice[T]) InsertInPlace(i Int, values ...T) { sl.ReplaceInPlace(i, i, values...) }

// Replace replaces the elements of sl[i:j] with the given values, and returns
// a new slice with the modifications. The original slice remains unchanged.
// Replace panics if sl[i:j] is not a valid slice of sl.
//
// Parameters:
//
// - i Int: The starting index of the slice to be replaced.
//
// - j Int: The ending index of the slice to be replaced.
//
// - values ...T: A variadic list of values to replace the existing slice.
//
// Returns:
//
// - Slice[T]: A new Slice containing the original elements with the specified elements replaced.
//
// Example usage:
//
//	slice := g.Slice[string]{"a", "b", "c", "d"}
//	newSlice := slice.Replace(1, 3, "e", "f")
//
// The original slice remains ["a", "b", "c", "d"], and the newSlice will be: ["a", "e", "f", "d"].
func (sl Slice[T]) Replace(i, j Int, values ...T) Slice[T] {
	i = sl.bound(i)
	j = sl.bound(j)

	if i > j {
		return NewSlice[T]()
	}

	total := sl[:i].Len() + Int(len(values)) + sl[j:].Len()
	slice := NewSlice[T](total)

	copy(slice, sl[:i])
	copy(slice[i:], values)
	copy(slice[i+Int(len(values)):], sl[j:])

	return slice
}

// ReplaceInPlace replaces the elements of sl[i:j] with the given values,
// and modifies the original slice in place. ReplaceInPlace panics if sl[i:j]
// is not a valid slice of sl.
//
// Parameters:
//
// - i int: The starting index of the slice to be replaced.
//
// - j int: The ending index of the slice to be replaced.
//
// - values ...T: A variadic list of values to replace the existing slice.
//
// Example usage:
//
//	slice := g.Slice[string]{"a", "b", "c", "d"}
//	slice.ReplaceInPlace(1, 3, "e", "f")
//
// After the ReplaceInPlace operation, the resulting slice will be: ["a", "e", "f", "d"].
func (sl *Slice[T]) ReplaceInPlace(i, j Int, values ...T) {
	i = sl.bound(i)
	j = sl.bound(j)

	if i > j {
		*sl = (*sl)[:0]
		return
	}

	if i == j {
		if len(values) > 0 {
			*sl = append((*sl)[:i], append(values, (*sl)[i:]...)...)
		}

		return
	}

	diff := Int(len(values)) - (j - i)

	if diff > 0 {
		*sl = append(*sl, NewSlice[T](diff)...)
	}

	copy((*sl)[i+Int(len(values)):], (*sl)[j:])
	copy((*sl)[i:], values)

	if diff < 0 {
		*sl = (*sl)[:(*sl).Len()+diff]
	}
}

// AddUnique appends unique elements from the provided arguments to the current slice.
//
// The function iterates over the provided elements and checks if they are already present
// in the slice. If an element is not already present, it is appended to the slice. The
// resulting slice is returned, containing the unique elements from both the original
// slice and the provided elements.
//
// Parameters:
//
// - elems (...T): A variadic list of elements to be appended to the slice.
//
// Returns:
//
// - Slice[T]: A new slice containing the unique elements from both the original slice
// and the provided elements.
//
// Example usage:
//
//	slice := g.Slice[int]{1, 2, 3, 4, 5}
//	slice = slice.AddUnique(3, 4, 5, 6, 7)
//	fmt.Println(slice)
//
// Output: [1 2 3 4 5 6 7].
func (sl Slice[T]) AddUnique(elems ...T) Slice[T] {
	for _, elem := range elems {
		if !sl.Contains(elem) {
			sl = append(sl, elem)
		}
	}

	return sl
}

// AddUniqueInPlace appends unique elements from the provided arguments to the current slice.
//
// The function iterates over the provided elements and checks if they are already present
// in the slice. If an element is not already present, it is appended to the slice.
//
// Parameters:
//
// - elems (...T): A variadic list of elements to be appended to the slice.
//
// Example usage:
//
//	slice := g.Slice[int]{1, 2, 3, 4, 5}
//	slice.AddUniqueInPlace(3, 4, 5, 6, 7)
//	fmt.Println(slice)
//
// Output: [1 2 3 4 5 6 7].
func (sl *Slice[T]) AddUniqueInPlace(elems ...T) {
	for _, elem := range elems {
		if !sl.Contains(elem) {
			*sl = append(*sl, elem)
		}
	}
}

// Get returns the element at the given index, handling negative indices as counting from the end
// of the slice.
func (sl Slice[T]) Get(index Int) T { return sl[sl.bound(index)] }

// Max returns the maximum element in the slice, assuming elements are comparable.
func (sl Slice[T]) Max() T {
	if sl.Empty() {
		return *new(T)
	}

	maxi := sl[0]

	for _, v := range sl[1:] {
		if sl.Less(sl.Index(maxi), sl.Index(v)) {
			maxi = v
		}
	}

	return maxi
}

// Min returns the minimum element in the slice, assuming elements are comparable.
func (sl Slice[T]) Min() T {
	if sl.Empty() {
		return *new(T)
	}

	mini := sl[0]

	for _, v := range sl[1:] {
		if sl.Less(sl.Index(v), sl.Index(mini)) {
			mini = v
		}
	}

	return mini
}

// Shuffle shuffles the elements in the slice randomly.
// This method modifies the original slice in place.
//
// The function uses the crypto/rand package to generate random indices.
//
// Returns:
//
// - Slice[T]: The modified slice with the elements shuffled randomly.
//
// Example usage:
//
// slice := g.Slice[int]{1, 2, 3, 4, 5}
// shuffled := slice.Shuffle()
// fmt.Println(shuffled)
//
// Output: A randomly shuffled version of the original slice, e.g., [4 1 5 2 3].
func (sl Slice[T]) Shuffle() {
	n := sl.Len()

	for i := n - 1; i > 0; i-- {
		j := rand.N(i + 1)
		sl.swap(i, j)
	}
}

// Reverse reverses the order of the elements in the slice.
// This method modifies the original slice in place.
//
// Returns:
//
// - Slice[T]: The modified slice with the elements reversed.
//
// Example usage:
//
// slice := g.Slice[int]{1, 2, 3, 4, 5}
// slice.Reverse()
// fmt.Println(slice)
//
// Output: [5 4 3 2 1].
func (sl Slice[T]) Reverse() { slices.Reverse(sl) }

// Sort sorts the elements in the slice in increasing order. It modifies the original
// slice in place. For proper functionality, the type T used in the slice must support
// comparison via the Less method.
// func (sl Slice[T]) Sort() { sort.Sort(sl) }

// SortBy sorts the elements in the slice using the provided comparison function.
// It modifies the original slice in place. It requires the elements to be of a type
// that is comparable.
//
// The function takes a custom comparison function as an argument and sorts the elements
// of the slice using the provided logic. The comparison function should return true if
// the element at index i should come before the element at index j, and false otherwise.
//
// Parameters:
//
// - f func(a, b T) cmp.Ordered: A comparison function that takes two indices i and j and returns a bool.
//
// Example usage:
//
// sl := NewSlice[int](1, 5, 3, 2, 4)
// sl.SortBy(func(a, b int) cmp.Ordering { return cmp.Cmp(a, b) }) // sorts in ascending order.
func (sl Slice[T]) SortBy(fn func(a, b T) cmp.Ordering) {
	slices.SortFunc(sl, func(a, b T) int { return int(fn(a, b)) })
}

// ToStringSlice converts the Slice into a slice of strings.
func (sl Slice[T]) ToStringSlice() []string {
	result := make([]string, 0, len(sl))

	for _, v := range sl {
		result = append(result, fmt.Sprint(v))
	}

	return result
}

// Join joins the elements in the slice into a single String, separated by the provided separator
// (if any).
func (sl Slice[T]) Join(sep ...T) String {
	var separator string
	if len(sep) != 0 {
		separator = fmt.Sprint(sep[0])
	}

	return String(strings.Join(sl.ToStringSlice(), separator))
}

// SubSlice returns a new slice containing elements from the current slice between the specified start
// and end indices, with an optional step parameter to define the increment between elements.
// The function checks if the start and end indices are within the bounds of the original slice.
// If the end index is negative, it represents the position from the end of the slice.
// If the start index is negative, it represents the position from the end of the slice counted
// from the start index.
//
// Parameters:
//
// - start (Int): The start index of the range.
//
// - end (Int): The end index of the range.
//
// - step (Int, optional): The increment between elements. Defaults to 1 if not provided.
// If negative, the slice is traversed in reverse order.
//
// Returns:
//
// - Slice[T]: A new slice containing elements from the current slice between the start and end
// indices, with the specified step.
//
// Example usage:
//
//	slice := g.Slice[int]{1, 2, 3, 4, 5, 6, 7, 8, 9}
//	subSlice := slice.SubSlice(1, 7, 2) // Extracts elements 2, 4, 6
//	fmt.Println(subSlice)
//
// Output: [2 4 6].
func (sl Slice[T]) SubSlice(start, end Int, step ...Int) Slice[T] {
	_step := Int(1)

	if len(step) != 0 {
		_step = step[0]
	}

	start = sl.bound(start, struct{}{})
	end = sl.bound(end, struct{}{})

	if (start >= end && _step > 0) || (start <= end && _step < 0) || _step == 0 {
		return NewSlice[T]()
	}

	var loopCondition func(Int) bool
	if _step > 0 {
		loopCondition = func(i Int) bool { return i < end }
	} else {
		loopCondition = func(i Int) bool { return i > end }
	}

	var slice Slice[T]

	for i := start; loopCondition(i); i += _step {
		slice = append(slice, sl[i])
	}

	return slice
}

// Cut removes a range of elements from the Slice and returns a new Slice.
// It creates two slices: one from the beginning of the original slice up to
// the specified start index (exclusive), and another from the specified end
// index (inclusive) to the end of the original slice. These two slices are
// then concatenated to form the resulting Slice.
//
// Parameters:
//
// - start (Int): The start index of the range to be removed.
//
// - end (Int): The end index of the range to be removed.
//
// Note:
//
//	The function also supports negative indices. Negative indices are counted
//	from the end of the slice. For example, -1 means the last element, -2
//	means the second-to-last element, and so on.
//
// Returns:
//
//	Slice[T]: A new slice containing elements from the current slice with
//	the specified range removed.
//
// Example:
//
//	slice := g.Slice[int]{1, 2, 3, 4, 5}
//	newSlice := slice.Cut(1, 3)
//	// newSlice is [1 4 5]
func (sl Slice[T]) Cut(start, end Int) Slice[T] { return sl.Replace(start, end) }

// CutInPlace removes a range of elements from the Slice in-place.
// It modifies the original slice by creating two slices: one from the
// beginning of the original slice up to the specified start index
// (exclusive), and another from the specified end index (inclusive)
// to the end of the original slice. These two slices are then
// concatenated to form the modified original Slice.
//
// Parameters:
//
// - start (Int): The start index of the range to be removed.
//
// - end (Int): The end index of the range to be removed.
//
// Note:
//
// The function also supports negative indices. Negative indices are counted
// from the end of the slice. For example, -1 means the last element, -2
// means the second-to-last element, and so on.
func (sl *Slice[T]) CutInPlace(start, end Int) { sl.ReplaceInPlace(start, end) }

// Random returns a random element from the slice.
//
// The function uses the crypto/rand package to generate a random index within the bounds of the
// slice. If the slice is empty, the zero value of type T is returned.
//
// Returns:
//
// - T: A random element from the slice.
//
// Example usage:
//
//	slice := g.Slice[int]{1, 2, 3, 4, 5}
//	randomElement := slice.Random()
//	fmt.Println(randomElement)
//
// Output: <any random element from the slice>.
func (sl Slice[T]) Random() T {
	if sl.Empty() {
		return *new(T)
	}

	return sl[rand.N(sl.Len())]
}

// Clone returns a copy of the slice.
func (sl Slice[T]) Clone() Slice[T] { return slices.Clone(sl) }

// LastIndex returns the last index of the slice.
func (sl Slice[T]) LastIndex() Int {
	if sl.NotEmpty() {
		return sl.Len() - 1
	}

	return 0
}

// Eq returns true if the slice is equal to the provided other slice.
func (sl Slice[T]) Eq(other Slice[T]) bool {
	switch o := any(other).(type) {
	case Slice[Int]:
		return slices.Equal(any(sl).(Slice[Int]), o)
	case Slice[String]:
		return slices.Equal(any(sl).(Slice[String]), o)
	case Slice[Float]:
		return slices.Equal(any(sl).(Slice[Float]), o)
	case Slice[int]:
		return slices.Equal(any(sl).(Slice[int]), o)
	case Slice[string]:
		return slices.Equal(any(sl).(Slice[string]), o)
	case Slice[bool]:
		return slices.Equal(any(sl).(Slice[bool]), o)
	case Slice[int8]:
		return slices.Equal(any(sl).(Slice[int8]), o)
	case Slice[int16]:
		return slices.Equal(any(sl).(Slice[int16]), o)
	case Slice[int32]:
		return slices.Equal(any(sl).(Slice[int32]), o)
	case Slice[int64]:
		return slices.Equal(any(sl).(Slice[int64]), o)
	case Slice[uint]:
		return slices.Equal(any(sl).(Slice[uint]), o)
	case Slice[uint8]:
		return slices.Equal(any(sl).(Slice[uint8]), o)
	case Slice[uint16]:
		return slices.Equal(any(sl).(Slice[uint16]), o)
	case Slice[uint32]:
		return slices.Equal(any(sl).(Slice[uint32]), o)
	case Slice[uint64]:
		return slices.Equal(any(sl).(Slice[uint64]), o)
	case Slice[float32]:
		return slices.Equal(any(sl).(Slice[float32]), o)
	case Slice[float64]:
		return slices.Equal(any(sl).(Slice[float64]), o)
	default:
		return sl.EqBy(other, func(x, y T) bool { return reflect.DeepEqual(x, y) })
	}
}

// EqBy reports whether two slices are equal using an equality
// function on each pair of elements. If the lengths are different,
// EqBy returns false. Otherwise, the elements are compared in
// increasing index order, and the comparison stops at the first index
// for which eq returns false.
func (sl Slice[T]) EqBy(other Slice[T], fn func(x, y T) bool) bool {
	return slices.EqualFunc(sl, other, fn)
}

// String returns a string representation of the slice.
func (sl Slice[T]) String() string {
	builder := NewBuilder()

	for _, v := range sl {
		builder.Write(Sprintf("%v, ", v))
	}

	return builder.String().TrimRight(", ").Format("Slice[%s]").Std()
}

// Append appends the provided elements to the slice and returns the modified slice.
func (sl Slice[T]) Append(elems ...T) Slice[T] { return append(sl, elems...) }

// AppendInPlace appends the provided elements to the slice and modifies the original slice.
func (sl *Slice[T]) AppendInPlace(elems ...T) { *sl = append(*sl, elems...) }

// Cap returns the capacity of the Slice.
func (sl Slice[T]) Cap() Int { return Int(cap(sl)) }

// Contains returns true if the slice contains the provided value.
func (sl Slice[T]) Contains(val T) bool { return sl.Index(val) >= 0 }

// ContainsBy returns true if the slice contains an element that satisfies the provided function fn, false otherwise.
func (sl Slice[T]) ContainsBy(fn func(t T) bool) bool { return sl.IndexBy(fn) >= 0 }

// ContainsAny checks if the Slice contains any element from another Slice.
func (sl Slice[T]) ContainsAny(values ...T) bool {
	if sl.Empty() || len(values) == 0 {
		return false
	}

	for _, v := range values {
		if sl.Contains(v) {
			return true
		}
	}

	return false
}

// ContainsAll checks if the Slice contains all elements from another Slice.
func (sl Slice[T]) ContainsAll(values ...T) bool {
	if sl.Empty() || len(values) == 0 {
		return false
	}

	for _, v := range values {
		if !sl.Contains(v) {
			return false
		}
	}

	return true
}

// Delete removes the element at the specified index from the slice and returns the modified slice.
func (sl Slice[T]) Delete(i Int) Slice[T] {
	nsl := sl.Clone()
	nsl.DeleteInPlace(i)

	return nsl.Clip()
}

// DeleteInPlace removes the element at the specified index from the slice and modifies the
// original slice.
func (sl *Slice[T]) DeleteInPlace(i Int) {
	i = sl.bound(i)
	copy((*sl)[i:], (*sl)[i+1:])
	*sl = (*sl)[:len(*sl)-1]
}

// Empty returns true if the slice is empty.
func (sl Slice[T]) Empty() bool { return len(sl) == 0 }

// Last returns the last element of the slice.
func (sl Slice[T]) Last() T { return sl.Get(-1) }

// Ne returns true if the slice is not equal to the provided other slice.
func (sl Slice[T]) Ne(other Slice[T]) bool { return !sl.Eq(other) }

// NeBy reports whether two slices are not equal using an inequality
// function on each pair of elements. If the lengths are different,
// NeBy returns true. Otherwise, the elements are compared in
// increasing index order, and the comparison stops at the first index
// for which fn returns true.
func (sl Slice[T]) NeBy(other Slice[T], fn func(x, y T) bool) bool { return !sl.EqBy(other, fn) }

// NotEmpty returns true if the slice is not empty.
func (sl Slice[T]) NotEmpty() bool { return !sl.Empty() }

// Pop returns the last element of the slice and a new slice without the last element.
func (sl Slice[T]) Pop() (T, Slice[T]) { return sl.Last(), sl.SubSlice(0, -1) }

// Set sets the value at the specified index in the slice and returns the modified slice.
// This method modifies the original slice in place.
//
// Parameters:
//
// - index (Int): The index at which to set the new value.
//
// - val (T): The new value to be set at the specified index.
//
// Returns:
//
// - Slice[T]: The modified slice with the new value set at the specified index.
//
// Example usage:
//
// slice := g.Slice[int]{1, 2, 3, 4, 5}
// slice.Set(2, 99)
// fmt.Println(slice)
//
// Output: [1 2 99 4 5].
func (sl Slice[T]) Set(index Int, val T) { sl[sl.bound(index)] = val }

// Len returns the length of the slice.
func (sl Slice[T]) Len() Int { return Int(len(sl)) }

// Less defines the comparison logic between two elements at indices i and j within the slice.
// It utilizes type-based comparisons for elements of various types like Int, int, String, string,
// Float, and float64. The comparison is performed according to the types and their respective
// comparison methods. If the types are not directly comparable, it returns false.
func (sl Slice[T]) Less(i, j Int) bool {
	elemI := any(sl[i])
	elemJ := any(sl[j])

	switch elemI := elemI.(type) {
	case Int:
		if elemJ, ok := elemJ.(Int); ok {
			return elemI.Lt(elemJ)
		}
	case String:
		if elemJ, ok := elemJ.(String); ok {
			return elemI.Lt(elemJ)
		}
	case Float:
		if elemJ, ok := elemJ.(Float); ok {
			return elemI.Lt(elemJ)
		}
	case string:
		if elemJ, ok := elemJ.(string); ok {
			return elemI < elemJ
		}
	case bool:
		if elemJ, ok := elemJ.(bool); ok {
			return !elemI && elemJ
		}
	case uint:
		if elemJ, ok := elemJ.(uint); ok {
			return elemI < elemJ
		}
	case uint8:
		if elemJ, ok := elemJ.(uint8); ok {
			return elemI < elemJ
		}
	case uint16:
		if elemJ, ok := elemJ.(uint16); ok {
			return elemI < elemJ
		}
	case uint32:
		if elemJ, ok := elemJ.(uint32); ok {
			return elemI < elemJ
		}
	case uint64:
		if elemJ, ok := elemJ.(uint64); ok {
			return elemI < elemJ
		}
	case int:
		if elemJ, ok := elemJ.(int); ok {
			return elemI < elemJ
		}
	case int8:
		if elemJ, ok := elemJ.(int8); ok {
			return elemI < elemJ
		}
	case int16:
		if elemJ, ok := elemJ.(int16); ok {
			return elemI < elemJ
		}
	case int32:
		if elemJ, ok := elemJ.(int32); ok {
			return elemI < elemJ
		}
	case int64:
		if elemJ, ok := elemJ.(int64); ok {
			return elemI < elemJ
		}
	case float32:
		if elemJ, ok := elemJ.(float32); ok {
			return Float(elemI).Lt(Float(elemJ))
		}
	case float64:
		if elemJ, ok := elemJ.(float64); ok {
			return Float(elemI).Lt(Float(elemJ))
		}
	}

	return false
}

// Swap swaps the elements at the specified indices in the slice.
// This method modifies the original slice in place.
//
// Parameters:
//
// - i (Int): The index of the first element to be swapped.
//
// - j (Int): The index of the second element to be swapped.
//
// Returns:
//
// - Slice[T]: The modified slice with the elements at the specified indices swapped.
//
// Example usage:
//
// slice := g.Slice[int]{1, 2, 3, 4, 5}
// slice.Swap(1, 3)
// fmt.Println(slice)
//
// Output: [1 4 3 2 5].
func (sl Slice[T]) Swap(i, j Int) {
	i = sl.bound(i)
	j = sl.bound(j)

	sl.swap(i, j)
}

func (sl Slice[T]) swap(i, j Int) { sl[i], sl[j] = sl[j], sl[i] }

// Grow increases the slice's capacity, if necessary, to guarantee space for
// another n elements. After Grow(n), at least n elements can be appended
// to the slice without another allocation. If n is negative or too large to
// allocate the memory, Grow panics.
func (sl Slice[T]) Grow(n Int) Slice[T] { return slices.Grow(sl, n.Std()) }

// Clip removes unused capacity from the slice.
func (sl Slice[T]) Clip() Slice[T] { return slices.Clip(sl) }

// Std returns a new slice with the same elements as the Slice[T].
func (sl Slice[T]) Std() []T { return sl }

// Print prints the elements of the Slice to the standard output (console)
// and returns the Slice unchanged.
func (sl Slice[T]) Print() Slice[T] { fmt.Println(sl); return sl }

// Unpack assigns values of the slice's elements to the variables passed as pointers.
// If the number of variables passed is greater than the length of the slice,
// the function ignores the extra variables.
//
// Parameters:
//
// - vars (...*T): Pointers to variables where the values of the slice's elements will be stored.
//
// Example:
//
//	slice := g.Slice[int]{1, 2, 3, 4, 5}
//	var a, b, c int
//	slice.Unpack(&a, &b, &c)
//	fmt.Println(a, b, c) // Output: 1 2 3
func (sl Slice[T]) Unpack(vars ...*T) {
	if len(vars) > len(sl) {
		vars = vars[:len(sl)]
	}

	for i, v := range vars {
		*v = sl[i]
	}
}

func (sl Slice[T]) bound(i Int, subslice ...struct{}) Int {
	ii := i
	if ii < 0 {
		ii += sl.Len()
	}

	negative := Int(0)
	if len(subslice) != 0 {
		negative = -1
	}

	if ii > sl.Len() || ii < negative {
		panic(fmt.Sprintf("runtime error: slice bounds out of range [%d] with length %d", i, len(sl)))
	}

	return ii
}