system-praktyk-api/src/InternshipSystem.Core/Entity/Internship/Internship.cs

using System.Collections.Generic;
using System.Linq;

namespace InternshipSystem.Core
{
    public class Internship
    {
        public long Id { get; set; }
        public Student Student { get; set; }
        public InternshipRegistration InternshipRegistration { get; set; }
        public InternshipProgram InternshipProgram { get; set; }
        public Report Report { get; set; }
        public List<Document> Approvals { get; set; }
        public List<Document> Documentation { get; set; }
        public float? Grade { get; set; }    

        public Edition Edition { get; set; }

        public void UpdateDocument(Document document)
        {
            var oldDocument = Documentation.First(d => d.Id == document.Id);

            oldDocument.Description = document.Description ?? oldDocument.Description;
            oldDocument.Scan = document.Scan ?? oldDocument.Scan;
            oldDocument.Type = document.Type;
            oldDocument.State = DocumentState.Submitted;
        }

        public void AddNewDocument(Document document)
        {
            document.State = DocumentState.Submitted;
            
            Documentation.Add(document);
        }

        public static Internship CreateStudentsInternship(Student student)
        {
            var internship = new Internship();

            internship.Student = student;

            internship.InternshipRegistration = InternshipRegistration.Create();
            internship.InternshipProgram = InternshipProgram.Create();
            internship.Report = Report.Create();
            internship.Approvals = new List<Document>();
            internship.Documentation = new List<Document>();

            return internship;
        }
    }
}