package main

import (
	"aoc/utils"
)

func parseStartLine(line string) []bool {
	runes := []rune(line)
	beams := make([]bool, len(runes))

	for idx, char := range runes {
		if char == 'S' {
			beams[idx] = true
		}
	}

	return beams
}

func stepOne(input chan string) (int, error) {
	beams := parseStartLine(<-input)
	splitCount := 0

	for line := range input {
		runes := []rune(line)
		for idx, char := range runes {
			if char == '^' && beams[idx] {
				splitCount++
				if idx > 0 {
					beams[idx-1] = true
				}
				if idx < len(runes)-1 {
					beams[idx+1] = true
				}
				beams[idx] = false
			}
		}
	}

	return splitCount, nil
}

func valueBeams(beams []bool) []int {
	valBeams := make([]int, len(beams))

	for idx, b := range beams {
		val := 0
		if b {
			val = 1
		}
		valBeams[idx] = val
	}

	return valBeams
}

func stepTwo(input chan string) (int, error) {
	beams := valueBeams(parseStartLine(<-input))

	for line := range input {
		runes := []rune(line)
		for idx, char := range runes {
			bc := beams[idx]
			if char == '^' && bc > 0 {
				beams[idx] = 0
				if idx > 0 {
					beams[idx-1] += bc
				}
				if idx < len(runes)-1 {
					beams[idx+1] += bc
				}
			}
		}
	}

	sum := 0
	for _, bc := range beams {
		sum += bc
	}

	return sum, nil
}

func main() {
	inputFile := utils.FilePath("day07.txt")
	utils.RunStep(utils.ONE, inputFile, stepOne)
	utils.RunStep(utils.TWO, inputFile, stepTwo)
}