package astar0

import "math"

// ManhattanFunc 曼哈顿
func ManhattanFunc(node, end *Node) int32 {
	x := Abs(node.x - end.x)
	y := Abs(node.y - end.y)
	return (x + y) * straightCost
}

// DiagonalFunc 对角线
func DiagonalFunc(node, end *Node) int32 {
	x := Abs(node.x - end.x)
	y := Abs(node.y - end.y)
	value := Min(x, y)
	return value*diagonalCost + Abs(x-y)*straightCost
}

// EuclideanFunc 欧几里得
func EuclideanFunc(node, end *Node) int32 {
	x := Abs(node.x - end.x)
	y := Abs(node.y - end.y)
	v := float64(x)*float64(x) + float64(y)*float64(y)
	return int32(math.Sqrt(v) * float64(straightCost))
}

func IsWalkableFunc() func(x, y, value int32) bool {
	return func(x, y, value int32) bool {
		return value == 0
	}
}