package two

import (
	"strings"

	log "github.com/sirupsen/logrus"
)

type graph struct {
	robot point
	data  []string
}

func newGraph() *graph {
	return &graph{}
}

func (g *graph) String() string {
	return strings.Join(g.data, "\n")
}

func (g *graph) valueAt(p point) rune {
	return rune(g.data[p.y][p.x])
}

func (g *graph) updateRobot(dir direction) {
	new := neighbours(g.robot)[dir]
	log.Debugf("new robot point: %v", new)

	g.updateEach(g.robot, '.')
	g.updateEach(new, '@')
	g.robot = new
}

func (g *graph) updateBox(p point, dir direction) {
	new := neighbours(p)[dir]

	g.updateEach(new, g.valueAt(p))
	g.updateEach(p, '.')
}

func (g *graph) updateEach(p point, r rune) {
	g.data[p.y] = replaceAtIndex(g.data[p.y], r, p.x)
}