AoCAutomaton provides skeleton classes and interfaces that makes Advent of Code even more enjoyable by simplifying mundane tasks, so you can concentrate on solving the puzzle.

AoCAutomaton implements an overall logic as well as some helpers. The overall workflow is implemented by the Automaton class. It will:

• create an instance of your solving logic
• fetch your specific input data (and cache them)
• tests your logic against sample/test data you may have provided (usually by copy pasting from the day's puzzle)
• if tests are not ok, it will stop. Otherwise
• runs your solving logic against your private input
• submit the answer to the AoC site
• get the result (and cache it) and provides you with the main message
• if this is not the good answer, it will stop. Otherwise
• it does the same for the second part of the question

AocAutomaton is designed to be used within your IDE of choice, focusing on reducing friction when solving AoC puzzles. Friction appears as the need to copy/paste your input data between the site and your code (either in line or as dedicated data files), but also when copy/pasting the answer or inputting manually, which leads to the occasional typo error. One can also add dealing with provided examples to use as test/validation input.

It does not try to provide you with standard algorithms and/or helpers to simplify the solving of the puzzle. I consider this could spoil the fun for most users. That being said, there is nothing wrong with building your own set of helper functions on top of this library; I may publish one as well at a later date. The important point is that this is a separate concern and will not be part of this library.

AocAutomation provides you an integration class that will implements interaction between your solver and the AoC ste. You just need to provide a class that contains the solving logic and implements a simple interface with only three methods.

In order to interact with the AoC site, AoCAutomaton requires your AoC session id. It is stored as an hexadecimal value in a session cookie; you must get this value (via your browser of choice and store it in an environment variable named AOC_SESSION. Bear in mind that these tokens have a lifetime of roughly a month so expect to have to refresh it through the website sometimes. As of now, there is limited error handling, so you will get some exception if the token is invalid

Note: early versions allowed to pass the session id as a set up parameter. I reverted that design due to the risk of having session ids with public visibility on GitHub (or elsewhere). It is more difficult to leak an environment variable.

Just add AocAutomaton to the project you (plan to) use for AdventOfCode. In the main method of your program, create an Automaton instance. Write an ISolver implementation for the puzzle you plan to solve and use the Automaton.RunDay method that will:

1. Fetch your data input from the AoC website
2. Run your solver against every test data you have provided, if any
3. Run your solver for question 1
4. Push the answer to AoC site
5. Repeat with question 2 if question 1 was successful.

internal class Program
{
    private void Main()
    {
        var automaton = new Automaton();
        automaton.RunDay<TheSolver>();
    }
}
...
internal class TheSolver : ISolver
{
  // provides the puzzle data
  public void SetupRun(Automaton automaton)
  {
    // set the day number (mandatory)
    automaton.Day = 12;
    // provides test data (optional)
    automaton.RegisterTestDataAndResult("test data", 12, 1);
  }
  
  // compute the answer to the first part
  public object GetAnswer1(string data)
  {
    // compute the answer
    ...
    return answer;
  }

  // compute the answer to the second part
  public object GetAnswer2(string data)
  {
    // compute the answer
    ...
    return answer;
  }
}

You can choose any of the design of each of your solver.

This is the default interface, with only three methods. It is recommended when the data parsing is straightforward, which is usually the case for the initial puzzles of each year. This is also the interface than must be implemented by any custom design you may provide.

public interface ISolver
{
  // provides the puzzle data
  void SetupRun(Automaton automaton);
  
  // compute the answer to the first part
  object GetAnswer1(string data);

  // compute the answer to the second part
  object GetAnswer2(string data);
}

. SetupRun(Automaton automaton) method: implement it to feed puzzle data (day and test values) to the automaton . GetAnswer[1|2](string data) methods: implement the input parsing and solving logic within each of these methods. Note than a solver instance will always receive the same data value for each method.

This abstract class offers a method to parse data outside of the solving logic. This design is perfect as soon as you want need to convert the input data to some specialized structure that will be stored as fields/properties. Parsing occurs only once per solver.

// this class definition is for documentation purpose
// actual definition is different 
public class SolverWithParser
{
  // provides the puzzle data
  public abstract void SetupRun(Automaton automaton);
  
  // compute the answer to the first part
  public abstract object GetAnswer1();

  // compute the answer to the second part
  public abstract object GetAnswer2();
  
  // parse the puzzle data
  protected abstract void Parse(string data);
}

This is a variant from the previous one. Most AoC puzzles use a data set consisting of one line records. Parsing will be implemented via the ParseLine method. It receives each line to parse, with its index and total number of lines.

// this class definition is for documentation purpose
// actual definition is different 
public class SolverWithParser
{
  // provides the puzzle data
  public abstract void SetupRun(Automaton automaton);
  
  // compute the answer to the first part
  public abstract object GetAnswer1();

  // compute the answer to the second part
  public abstract object GetAnswer2();
  
  // parse a single line
  protected abstract void ParseLine(string line, int index, int lineCount);
}