package day1

import "core:strings"
import "core:testing"
import strconv "core:strconv"
import os "core:os"

sample :: `L68
L30
R48
L5
R60
L55
L1
L99
R14
L82`

solve_first :: proc(s: string) -> uint {
    s := s
    pointing_at_zero: uint
    current_dial := 50
    for line in strings.split_lines_iterator(&s) {
        if line == "" do continue
        value, _ := strconv.parse_int(line[1:])
        if line[0] == 'L' {
            current_dial -= value
        } else {
            current_dial += value
        }


        for current_dial < 0 {
            current_dial += 100
        }
        for current_dial >= 100 {
            current_dial -= 100
        }

        if current_dial == 0 {
            pointing_at_zero += 1
        }
    }
    return pointing_at_zero
}

solve_second :: proc(s: string) -> uint {
    s := s
    pointing_at_zero: uint
    current_dial := 50
    for line in strings.split_lines_iterator(&s) {
        if line == "" do continue
        value, _ := strconv.parse_int(line[1:])
        for value >= 100 {
            value -= 100
            pointing_at_zero += 1
        }
        if line[0] == 'L' {
            current_dial -= value
        } else {
            current_dial += value
        }

        for current_dial < 0 {
            current_dial += 100
            pointing_at_zero += 1
        }
        for current_dial > 100 {
            current_dial -= 100
            pointing_at_zero += 1
        }

        if current_dial == 0 {
            pointing_at_zero += 1
        }
    }
    return pointing_at_zero
}

@(test)
solve_first_sample :: proc(t: ^testing.T) {
    pointing_at_zero := solve_first(sample)
    testing.expect_value(t, pointing_at_zero, 3)
}

@(test)
solve_first_input :: proc(t: ^testing.T) {
    contents, _ := os.read_entire_file("day1/input.txt")
    defer delete(contents)
    pointing_at_zero := solve_first(string(contents))
    testing.expect_value(t, pointing_at_zero, 1158)
}

@(test)
solve_second_sample :: proc(t: ^testing.T) {
    pointing_at_zero := solve_second(sample)
    testing.expect_value(t, pointing_at_zero, 6)
}

@(test)
solve_second_input :: proc(t: ^testing.T) {
    contents, _ := os.read_entire_file("day1/input.txt")
    defer delete(contents)
    pointing_at_zero := solve_second(string(contents))
    testing.expect_value(t, pointing_at_zero, 6860)
}