// https://dotnetfiddle.net/xoooUE

using System;

using System.Collections.Generic;

using System.Linq;

using Newtonsoft.Json;

​

public class Program

{

    public static void Main()

    {

        var jobs = new Jobs("F1");

        jobs.Add("O1", "P1", "V1");

        jobs.Add("O1", "P2", "V2");

        jobs.Add("O2", "P3", "V3");

        jobs.Add("O2", "P4", "V4");

        jobs.Add("O2", "P5", new Task("V5"));

        jobs.Add("O2", "P6", new Task("V6"));

        jobs.Add("O1", "P7", new Task("V7"));

        jobs.Add("O1", "P8", new Task("V8"));

        Console.WriteLine(JsonConvert.SerializeObject(jobs));

        Console.WriteLine(JsonConvert.SerializeObject(jobs.GetByProductId("P9")));

    }   

}

​

​

​

public class Jobs

{

    public string FactoryName { get; private set; }

    public Dictionary<string, Dictionary<string, List<Task>>> Tasks { get; private set; } = new Dictionary<string, Dictionary<string, List<Task>>>();

    public Jobs() {}

    public Jobs(string factoryName)

    {

        FactoryName = factoryName;

    }

    public void Add(string orderId, string productId, Task task)

    {

        if(!Tasks.TryAdd(orderId, new Dictionary<string, List<Task>>() {{ productId, new List<Task>() { task }}})) { //add order if not existing

            if(!Tasks[orderId].TryAdd(productId, new List<Task>() {task})) { //add product if not existing

                Tasks[orderId][productId].Add(task); //add tasks

            }

        }

    }

    public void Add(string orderId, string productId, string field)

    {

        Add(orderId, productId, new Task(field));

    }

    public List<Task> GetByProductId(string productId)

    {

        var productDict = Tasks.Values.SingleOrDefault(x => x.ContainsKey(productId));

        return (productDict == null) ? null : productDict.GetValueOrDefault(productId);

    }

}

​

public class Task

{

    public string Field { get; private set; }

    public Task(string field)

    {

        Field = field;

    }

}

​

​

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​

​

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