package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
	"strings"
	"time"
)

func main() {
	start := time.Now()
	partOne()
	duration := time.Since(start)
	partTwo()
	duration2 := time.Since(start)
	fmt.Printf("p1: %s, p2: %s\n", duration, duration2-duration)
}

func makeScanner(test bool) *bufio.Scanner {
	var f *os.File
	if test {
		f, _ = os.Open("inputs/testinput")
	} else {
		f, _ = os.Open("inputs/input")
	}
	reader := bufio.NewReader(f)
	return bufio.NewScanner(reader)
}

func mustAtoi(line string) int {
	i, _ := strconv.Atoi(line)
	return i
}

func fuelCostPartOne(crabs []int, column int) int {
	var totalFuel int
	for _, v := range crabs {
		if column < v {
			totalFuel += v - column
		}
		if column > v {
			totalFuel += column - v
		}
	}
	return totalFuel
}

func fuelCostPartTwo(crabs []int, column int) int {
	var totalFuel int
	for _, v := range crabs {
		if column < v {
			totalFuel += ((v - column) * ((v - column) + 1)) / 2
		}
		if column > v {
			totalFuel += ((column - v) * ((column - v) + 1)) / 2
		}
	}
	return totalFuel
}

func partOne() {
	scanner := makeScanner(false)

	// just a single line today
	scanner.Scan()
	input := strings.Split(scanner.Text(), ",")
	crabs := []int{}
	var max int
	for _, v := range input {
		crab := mustAtoi(v)
		crabs = append(crabs, crab)
		if max < crab {
			max = crab
		}
	}
	lowestFuel := 1000000000 // some initial awful max fuel cost
	for i := 0; i <= max; i++ {
		cost := fuelCostPartOne(crabs, i)
		if cost < lowestFuel {
			lowestFuel = cost
		}
	}
	fmt.Println(lowestFuel)
}

func partTwo() {
	scanner := makeScanner(false)

	// just a single line today
	scanner.Scan()
	input := strings.Split(scanner.Text(), ",")
	crabs := []int{}
	var max int
	for _, v := range input {
		crab := mustAtoi(v)
		crabs = append(crabs, crab)
		if max < crab {
			max = crab
		}
	}
	lowestFuel := 1000000000 // some initial awful max fuel cost
	for i := 0; i <= max; i++ {
		cost := fuelCostPartTwo(crabs, i)
		if cost < lowestFuel {
			lowestFuel = cost
		}
	}
	fmt.Println(lowestFuel)
}