package main

import (
	"bufio"
	_ "embed"
	"fmt"
	"strings"

	aoc "go.sour.is/advent-of-code"
)

// var log = aoc.Log

func main() { aoc.MustResult(aoc.Runner(run)) }

type result struct {
	valuePT1 int
	valuePT2 int
}

func (r result) String() string { return fmt.Sprintf("%#v", r) }

func run(scan *bufio.Scanner) (*result, error) {

	sum := 0
	sum2 := 0

	for scan.Scan() {
		txt := scan.Text()
		row := aoc.ReadStringToInts(strings.Fields(txt))

		good, bad := testSafety(row)
		if good {
			sum++
			sum2++
			continue
		}

		for i := max(0, bad-1); i < min(bad+2, len(row)); i++ {
			arr := cut(i, row)

			good, _ := testSafety(arr)
			if good {
				sum2++
				break
			}
		}
	}

	return &result{valuePT1: sum, valuePT2: sum2}, nil
}

func testSafety(row []int) (bool, int) {
	good := true
	bad := -1
	increasing := false
	decreasing := false

	for i, v := range row[1:] {
		if v > row[i] {
			increasing = true
		}
		if v < row[i] {
			decreasing = true
		}

		if difference := aoc.ABS(v - row[i]); difference < 1 || difference > 3 {
			good = false
			bad = i
			break
		}

		if increasing && decreasing {
			good = false
			bad = i
			break
		}
	}

	return good, bad
}

func cut(i int, values []int) []int {
	arr := make([]int, 0, len(values))
	arr = append(arr, values[:i]...)
	arr = append(arr, values[i+1:]...)
	return arr
}