package main

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

func findTrailheads(tmap [][]int) [][]int {
  trailheadsPositions := [][]int{}
  for i:=range tmap {
    for j:=range tmap[i] {
      if tmap[i][j] == 0 {
        trailheadsPositions = append(trailheadsPositions, []int{i,j})
      }
    }
  }
  return trailheadsPositions
}

func nextSteps(tmap [][]int, currentPosition []int) [][]int {
  paths := [][]int{}
  if currentPosition[0] - 1 >= 0 && tmap[currentPosition[0]-1][currentPosition[1]] == tmap[currentPosition[0]][currentPosition[1]] + 1 {
    paths = append(paths, []int{currentPosition[0]-1,currentPosition[1]})
  } 
  if currentPosition[0] + 1 < len(tmap) && tmap[currentPosition[0]+1][currentPosition[1]] == tmap[currentPosition[0]][currentPosition[1]] + 1 {
    paths = append(paths, []int{currentPosition[0]+1,currentPosition[1]})
  } 
  if currentPosition[1] + 1 < len(tmap[currentPosition[0]]) && tmap[currentPosition[0]][currentPosition[1]+1] == tmap[currentPosition[0]][currentPosition[1]] + 1 {
    paths = append(paths, []int{currentPosition[0],currentPosition[1]+1})
  } 
  if currentPosition[1] - 1 >= 0 && tmap[currentPosition[0]][currentPosition[1]-1] == tmap[currentPosition[0]][currentPosition[1]] + 1 {
    paths = append(paths, []int{currentPosition[0],currentPosition[1]-1})
  } 
  return paths
}

func calcPath(tmap [][]int, start []int) [][]int {
  path := [][]int{start}
  for i:=1;i<=9;i++ {
    nextStep := nextSteps(tmap,)
    if len(nextStep) > 0 {
      break
    } else {
      path = append(path, nextStep...)
    }
  }
  return path
}

func main() {
  file, _ := os.Open("test")
//  file, _ := os.Open("input")
  defer file.Close()
  scanner := bufio.NewScanner(file)
  tmap := [][]int{}
  for scanner.Scan() {
    line := scanner.Text()
    level := strings.Split(line,"")
    levelInt := []int{}
    for i:=range level {
      levelInteger, _ := strconv.Atoi(level[i])
      levelInt = append(levelInt, levelInteger)
    }
    tmap = append(tmap, levelInt)
  }
  trailheadsPositions := findTrailheads(tmap)
  for i := range trailheadsPositions {
    path := calcPath(tmap,trailheadsPositions[i])
    fmt.Println(path)
    if len(path) == 10 {
      
    }
  }
}