package main

import (
	"fmt"
	"strconv"
	"strings"

	h "git.bullercodeworks.com/brian/adventofcode/helpers"
)

func main() {
	inp := h.StdinToStringSlice()
	part1(inp)
	fmt.Println()
	part2(inp)
}

func part1(input []string) {
	dirMap := map[byte]h.Coordinate{
		'U': h.Coordinate{X: 0, Y: -1},
		'R': h.Coordinate{X: 1, Y: 0},
		'D': h.Coordinate{X: 0, Y: 1},
		'L': h.Coordinate{X: -1, Y: 0},
	}

	curr, area := h.Coordinate{X: 0, Y: 0}, 0
	for i := range input {
		pts := strings.Fields(input[i])
		dir, length, _ := pts[0][0], h.Atoi(pts[1]), strings.Trim(pts[1], "()")
		n := curr.Add(dirMap[dir].Mul(length))
		area += curr.X*n.Y - curr.Y*n.X + length
		curr = n
	}
	fmt.Println("# Part 1")
	fmt.Println(area/2 + 1)
}

func part2(input []string) {
	dirMap := map[byte]h.Coordinate{
		'3': h.Coordinate{X: 0, Y: -1},
		'0': h.Coordinate{X: 1, Y: 0},
		'1': h.Coordinate{X: 0, Y: 1},
		'2': h.Coordinate{X: -1, Y: 0},
	}

	hexToDec := func(hex string) int {
		v, _ := strconv.ParseInt(hex, 16, strconv.IntSize)
		return int(v)
	}
	curr, area := h.Coordinate{X: 0, Y: 0}, 0
	for i := range input {
		pts := strings.Fields(input[i])
		pts[2] = strings.Trim(pts[2], "#()")
		length := hexToDec(pts[2][:len(pts[2])-1])
		dir := pts[2][len(pts[2])-1:][0]

		n := curr.Add(dirMap[dir].Mul(length))
		area += curr.X*n.Y - curr.Y*n.X + length
		curr = n
	}
	fmt.Println("# Part 2")
	fmt.Println(area/2 + 1)
}