package graphs

type Number interface {
	~int | ~int8 | ~int16 | ~int32 | ~int64 |
		~uint | ~uint8 | ~uint16 | ~uint32 | ~uint64 |
		~float32 | ~float64
}

// Weighted Graph , undirected
type WeightedGraph[T comparable, W Number] struct {
	adjList map[T]map[T]W
}

// NewWeightedGraph() -> Creates a Weighted Graph.
//
//	gg := graphs.NewWeightedGraph[string, int]()
func NewWeightedGraph[T comparable, W Number]() *WeightedGraph[T, W] {
	gp := &WeightedGraph[T, W]{
		adjList: make(map[T]map[T]W),
	}

	return gp
}

// AddVertex() -> add vertex connected to vertex with weight
func (gp *WeightedGraph[T, W]) AddVertex(newVertex T, connectToVertex T, weight W) bool {
	// early return
	if newVertex == connectToVertex {
		return false
	}

	gp.AddIsolatedVertex(newVertex)
	gp.AddIsolatedVertex(connectToVertex)

	_, exist := gp.adjList[newVertex][connectToVertex]

	if !exist {
		gp.adjList[newVertex][connectToVertex] = weight
		gp.adjList[connectToVertex][newVertex] = weight
		return true
	}

	return false
}

// AddIsolatedVertex() -> Creates an isolated Vertex returns True if ok ,
// false if vertex already exist
func (gp *WeightedGraph[T, W]) AddIsolatedVertex(newVertex T) bool {
	_, exist := gp.adjList[newVertex]
	if !exist {
		gp.adjList[newVertex] = make(map[T]W)
		return true
	}
	return false
}

// ConnectEdge() -> Connects two already existing vertices with a weighted edge.
// Returns false if either vertex is missing or the edge is already there.
func (gp *WeightedGraph[T, W]) ConnectEdge(vertex T, to T, weight W) bool {
	if _, exist := gp.adjList[vertex]; !exist {
		return false
	}

	if _, exist := gp.adjList[to]; !exist {
		return false
	}

	return gp.AddVertex(vertex, to, weight)
}

// Display()
func (gp *WeightedGraph[T, W]) Display() map[T]map[T]W {
	return gp.adjList
}

// Order() -> returns the amount of Vertices
func (gp *WeightedGraph[T, W]) Order() int {
	return len(gp.adjList)
}

// Size() -> returns the amount of Edges
func (gp *WeightedGraph[T, W]) Size() int {
	var size int

	for _, inner := range gp.adjList {
		size += len(inner)
	}

	return size / 2
}