using System.Collections.Concurrent;

namespace AoC2024.day_19;

public class Day19 { private ConcurrentDictionary<string,ulong> _cachedPossibilities = new ConcurrentDictionary<string, ulong>();

public void GoPart1()
{
    var inputText = File.ReadAllText("\\AdventOfCode2024\\AoC\\src\\day_19\\input.txt");
    var availableTowels = GetAvailableTowels(inputText);
    var requiredPatterns = GetTargetPatterns(inputText);
    int reachablePatterns = 0;
    
    foreach (var targetPattern in requiredPatterns)
    {
        var result = DoTowelsMatch(targetPattern, availableTowels);

        if (result.Item1)
        {
            reachablePatterns++;
            Console.WriteLine($"Target pattern {targetPattern} can be reached with the following towels: {result.Item2.Aggregate("",(s, s1) => $"{s},{s1}")}");
        }
        else
        {
            Console.WriteLine($"Target pattern {targetPattern} can't be reached");
        }
    }
    
    Console.WriteLine($"reachable patterns: {reachablePatterns}");
}

public void GoPart2()
{
    var inputText = File.ReadAllText("\\AdventOfCode2024\\AoC\\src\\day_19\\input.txt");
    //var inputText = File.ReadAllText("\\AdventOfCode2024\\AoC\\src\\day_19\\testInput.txt");
    var availableTowels = GetAvailableTowels(inputText);
    var requiredPatterns = GetTargetPatterns(inputText);
    ulong patternCount = 0;
    
    var tasks = new List<Task<ulong>>();
    
   // requiredPatterns = requiredPatterns.Take(5).ToList();
    
    
    foreach (var targetPattern in requiredPatterns)
    {
        var task = new Task<ulong>(() =>
        {
            Console.WriteLine(targetPattern);
            ulong taskPatternCount = 0;
            var result = DoTowelsMatch2(targetPattern, availableTowels);

            if (result.Item1)
            {
                taskPatternCount = result.Item2;
                Console.WriteLine($"Target pattern {targetPattern} can be reached with {result.Item2} permutations");
            }
            else
            {
                Console.WriteLine($"Target pattern {targetPattern} can't be reached");
            }

            return taskPatternCount;
        });
        
        task.Start();
        tasks.Add(task);
    }

    Task.WaitAll(tasks);

    tasks.ForEach(task => patternCount += task.Result);
    Console.WriteLine($"{tasks.Count(task => task.Result > 0)} of the patterns were achieved");
    
    Console.WriteLine($"reachable patterns: {patternCount}");
}

private (bool,ulong) DoTowelsMatch2(string targetPattern, List<string> towelPatterns)
{
    ulong possiblePatternCount = 0;
   
    if (_cachedPossibilities.ContainsKey(targetPattern))
    {
        _cachedPossibilities.TryGetValue(targetPattern, out possiblePatternCount);
        return (possiblePatternCount > 0,possiblePatternCount);
    }
    
    foreach (var towelPattern in towelPatterns)
    {
        if (targetPattern.StartsWith(towelPattern))
        {
            var newTargetPattern = targetPattern.Substring(towelPattern.Length);

            if (string.IsNullOrEmpty(newTargetPattern))
            {
                possiblePatternCount++;
                continue;
            }
            
            var doTowelsMatchResult = DoTowelsMatch2(newTargetPattern, towelPatterns);
            if (doTowelsMatchResult.Item1)
            {
                possiblePatternCount += doTowelsMatchResult.Item2;
            }
        }
    }

    _cachedPossibilities.TryAdd(targetPattern, possiblePatternCount);
    
    return (possiblePatternCount>0,possiblePatternCount);
}

private (bool,List<string>?) DoTowelsMatch(string targetPattern, List<string> towelPatterns)
{
    foreach (var towelPattern in towelPatterns)
    {
        if (targetPattern.StartsWith(towelPattern))
        {
            var newTargetPattern = targetPattern.Substring(towelPattern.Length);

            if (string.IsNullOrEmpty(newTargetPattern))
            {
                return (true, new List<string>(){ towelPattern });
            }
            
            var doTowelsMatchResult = DoTowelsMatch(newTargetPattern, towelPatterns);
            if (doTowelsMatchResult.Item1)
            {
                doTowelsMatchResult.Item2.Insert(0, towelPattern);
                return (true, doTowelsMatchResult.Item2);
            }
        }
    }

    return (false,null);
}

private List<string> GetAvailableTowels(string input)
{
    return input.Split(Environment.NewLine, StringSplitOptions.RemoveEmptyEntries).First().Split(',', StringSplitOptions.RemoveEmptyEntries).Select(s => s.Trim()).ToList();
}

private List<string> GetTargetPatterns(string input)
{
    var lines = input.Split(Environment.NewLine, StringSplitOptions.RemoveEmptyEntries).ToList();
    lines.RemoveAt(0);
    return lines.Select(s => s.Trim()).ToList();
}

}

namespace AoC2024.Day_18;

public class Day18 {

public const string CLEAR = ".";
public const string BLOCKED = "#";
public const string TRAVELED = "O";

public void Go()
{
    var testGrid = GenerateGrid(71, 71);
    PrintGrid(testGrid);
    var coords = GetInputCoordinates(File.ReadAllText("\\AdventOfCode2024\\AoC\\src\\Day_18\\input.txt"));
    
    testGrid = ApplyCoords(testGrid, coords.Take(1024).ToList(), BLOCKED);
    PrintGrid(testGrid);
    FloodFillGrid(testGrid, new Coordinate(0,0), new (70,70));
}

public void GoPart2()
{
    var testGrid = GenerateGrid(71, 71);
    PrintGrid(testGrid);
    var coords = GetInputCoordinates(File.ReadAllText("\\AdventOfCode2024\\AoC\\src\\Day_18\\input.txt"));

    for (int i = 1; i <= coords.Count; i++)
    {
        testGrid = ApplyCoords(testGrid, coords.Take(i).ToList(), BLOCKED);
        PrintGrid(testGrid);
        var result = FloodFillGrid(testGrid, new Coordinate(0,0), new (70,70));
        if (result.Item2 == int.MaxValue)
        {
            var badCoord = coords[i - 1];
            Console.WriteLine($"!!!!Coord Number: {i} with a value of ({badCoord.Column},{badCoord.Row}) IS A BLOCKER!!!!");
            break;
        }
        else if (i%100 == 0)
        {
            var goodCoord = coords[i - 1];
            Console.WriteLine($"Coord Number: {i} with a value of ({goodCoord.Column},{goodCoord.Row}) allows an exit in {result.Item2} steps");
        }
    }
}

public List<List<string>> GenerateGrid(int width, int height)
{
    var grid = new List<List<string>>();
    for (int i = 0; i < height; i++)
    {
        var row = new List<string>();
        for (int j = 0; j < width; j++)
        {
            row.Add(CLEAR);
        }
        grid.Add(row);
    }

    return grid;
}

public void PrintGrid(List<List<string>> grid)
{
    // foreach (var row in grid)
    // {
    //     foreach (var value in row)
    //     {
    //         Console.Write($" {value} ");
    //     }
    //     Console.WriteLine();
    // }
}

public List<List<string>> ApplyCoords(List<List<string>> grid, List<Coordinate> coordinates, string value)
{
    foreach (var coord in coordinates)
    {
        grid[coord.Row][coord.Column] = value;
    }

    return grid;
}

public List<Coordinate> GetInputCoordinates(string input)
{
    var coords = new List<Coordinate>();
    foreach (var pair in input.Split(Environment.NewLine, StringSplitOptions.RemoveEmptyEntries))
    {
        var values = pair.Split(',', StringSplitOptions.RemoveEmptyEntries);
        coords.Add(new Coordinate(values[1], values[0]));
    }

    return coords;
}

public (List<List<string>>, int) FloodFillGrid(List<List<string>> grid, Coordinate start, Coordinate target)
{
    var newGrid = grid.Select(list => new List<string>(list)).ToList();
    var previousGrid = grid;
    newGrid[start.Row][start.Column] = TRAVELED;
    int stepCounter = 0;
    while (newGrid[target.Row][target.Column] != TRAVELED)
    {
        bool valueUpdatedInLoop = false;
        previousGrid = newGrid;
        newGrid = newGrid.Select(list => new List<string>(list)).ToList().ToList();
        
        for (var row = 0; row < grid.Count; row++)
        {
            for (var column = 0; column < grid[row].Count; column++)
            {
                if (previousGrid[row][column] == CLEAR && IsAdjacentEqual(previousGrid, new Coordinate(row,column), TRAVELED))
                {
                    newGrid[row][column] = TRAVELED;
                    valueUpdatedInLoop = true;
                }
            }
        }
        stepCounter++;

        if (!valueUpdatedInLoop)
        {
            return (newGrid,int.MaxValue);
        }
        
        //Console.WriteLine($"Step counter: {stepCounter}");
        PrintGrid(newGrid);
        
    }

    return (newGrid,stepCounter);
}

private bool IsAdjacentEqual(List<List<string>> grid, Coordinate location, string value)
{
    if (location.Row < grid.Count-1 && grid[location.Row+1][location.Column] == value)
    {
        return true;
    }
    
    if (location.Column < grid[0].Count-1 && grid[location.Row][location.Column+1] == value)
    {
        return true;
    }

    if (location.Row > 0 && grid[location.Row-1][location.Column] == value)
    {
        return true;
    }
    
    if (location.Column > 0 && grid[location.Row][location.Column-1] == value)
    {
        return true;
    }

    return false;
}

public struct Coordinate
{
    public Coordinate(int row, int column)
    {
        Row = row;
        Column = column;
    }
    
    public Coordinate(string row, string column)
    {
        Row = int.Parse(row);
        Column = int.Parse(column);
    }
    
    public int Row { get; set; }
    public int Column { get; set; }
}

}

`

pub mod task_2 {

pub fn task_1(input: &str) -> i32{
    let mut valid_count = 0;

    let reports = process_input(input);

    for report in reports{
        let valid = is_report_valid(report);

        if valid{
            valid_count += 1;
        }
    }

    println!("Valid count: {}", valid_count);
    valid_count
}

pub fn task_2(input: &str) -> i32{
    let mut valid_count = 0;

    let reports = process_input(input);

    for report in reports{
        let mut valid = is_report_valid(report.clone());

        if !valid
        {
            for position_to_delete in 0..report.len()
            {
                let mut updated_report = report.clone();
                updated_report.remove(position_to_delete);
                valid = is_report_valid(updated_report);

                if valid { break; }
            }
        }

        if valid{
            valid_count += 1;
        }
    }

    println!("Valid count: {}", valid_count);
    valid_count
}

fn is_report_valid(report:Vec<i32>) -> bool{
    let mut increasing = false;
    let mut decreasing = false;
    let mut valid = true;

    for position in 1..report.len(){
        if report[position-1] > report[position]
        {
            decreasing = true;
        }
        else if report[position-1] < report[position]
        {
            increasing = true;
        }
        else
        {
            valid = false;
            break;
        }

        if (report[position-1] - report[position]).abs() > 3
        {
            valid = false;
            break;
        }

        if increasing && decreasing
        {
            valid = false;
            break;
        }
    }

    return valid;
}

pub fn process_input(input: &str) -> Vec<Vec<i32>>{
    let mut reports: Vec<Vec<i32>> = Vec::new();
    for report_string in input.split("\n"){
        let mut report: Vec<i32> = Vec::new();
        for value in report_string.split_whitespace() {
            report.push(value.parse::<i32>().unwrap());
        }
        reports.push(report);
    }

    return reports;
}

}

`