package day02

import (
	"tools"
)

func getCodeFromDirections(keypad [][]string, startX, startY int, instructions []string) string {
	x := startX
	y := startY

	code := ""
	for _, line := range instructions {
		for _, inst := range line {
			switch inst {
			case 'L':
				if x > 0 && keypad[y][x-1] != "x" {
					x--
				}
			case 'R':
				if x < len(keypad[0])-1 && keypad[y][x+1] != "x" {
					x++
				}
			case 'U':
				if y > 0 && keypad[y-1][x] != "x" {
					y--
				}
			case 'D':
				if y < len(keypad)-1 && keypad[y+1][x] != "x" {
					y++
				}
			}
		}
		code += keypad[y][x]
	}

	return code
}

func Part1(puzzle tools.AoCPuzzle) interface{} {
	instructions := puzzle.GetInputArray()
	keypad := [][]string{
		{"1", "2", "3"},
		{"4", "5", "6"},
		{"7", "8", "9"},
	}

	return getCodeFromDirections(keypad, 1, 1, instructions)
}

func Part2(puzzle tools.AoCPuzzle) interface{} {
	instructions := puzzle.GetInputArray()
	keypad := [][]string{
		{"x", "x", "1", "x", "x"},
		{"x", "2", "3", "4", "x"},
		{"5", "6", "7", "8", "9"},
		{"x", "A", "B", "C", "x"},
		{"x", "x", "D", "x", "x"},
	}

	return getCodeFromDirections(keypad, 0, 2, instructions)
}