aoc2024/day-04/internal/two/matrix.go

package two

import (
	"fmt"
	"reflect"

	log "github.com/sirupsen/logrus"
)

type matrix [3][3]rune

func newMatrix(mid, nw, ne, se, sw rune) *matrix {
	return &matrix{
		{nw, -1, ne},
		{-1, mid, -1},
		{sw, -1, se},
	}
}

func (m *matrix) String() string {
	temp := [3][3]string{}
	for i := 0; i < 3; i++ {
		for j := 0; j < 3; j++ {
			temp[i][j] = string(m[i][j])
		}
	}
	return fmt.Sprintf("\n%s\n%s\n%s", temp[0], temp[1], temp[2])
}

func (m *matrix) rotate() *matrix {
	temp := matrix{}
	for i := 0; i < 3; i++ {
		for j := 0; j < 3; j++ {
			temp[3-j-1][i] = m[i][j]
		}
	}
	return &temp
}

func (m *matrix) isValid() bool {
	golden := &matrix{
		{'M', -1, 'M'},
		{-1, 'A', -1},
		{'S', -1, 'S'},
	}

	for range 4 {
		if reflect.DeepEqual(m, golden) {
			log.Debugf("%s \n---- %s", m.String(), golden.String())
			return true
		}
		golden = golden.rotate()
	}

	return false
}