aoc2023/day-16/mover.go

package main

import (
	"fmt"
)

type coords struct {
	X int
	Y int
}

func newCoords(x, y int) coords {
	return coords{X: x, Y: y}
}

// node represents a single node with coordinates and direction
type node struct {
	coords
	direction int
}

func newNode(x, y int, direction int) node {
	return node{coords: newCoords(x, y), direction: direction}
}

// String implements the fmt.Stringer interface
func (n node) String() string {
	return fmt.Sprintf("%v%s", n.coords, dirs[n.direction])
}

type mover struct {
	node
	nodes []node
}

// newMover sets the start coordinates and direction
// it returns a mover type
func newMover(n node) *mover {
	return &mover{node: n, nodes: make([]node, 0)}
}

// direction returns the current node direction
func (m *mover) direction() int {
	return m.node.direction
}

// setDirection sets the current node direction
func (m *mover) setDirection(val int) {
	m.node.direction = val
}

// move shifts the X,Y coordinate by one depending on direction
func (m *mover) move() {
	switch m.node.direction {
	case N:
		m.Y--
	case S:
		m.Y++
	case W:
		m.X--
	case E:
		m.X++
	}
}