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

namespace ClassroomProject
{
    public class Classroom
    {
        public List<Student> Students { get; set; }
        public int Capacity { get; set; }
        public int Count => Students.Count;

        public Classroom(int capacity)
        {
            Capacity = capacity;
            Students = new List<Student>(capacity);
        }

        public string RegisterStudent(Student student)
        {
            if (this.Count < this.Capacity)
            {
                Students.Add(student);
                return $"Added student {student.FirstName} {student.LastName}";
            }
            else
            {
                return "No seats in the classroom";
            }
        }

        public string DismissStudent(string firstName, string lastName)
        {
            if (Students.Any(f => f.FirstName == firstName && f.LastName == lastName))
            {
                Student toRemove = Students.FirstOrDefault(f => f.FirstName == firstName && f.LastName == lastName);
                Students.Remove(toRemove);
                return $"Dismissed student {toRemove.FirstName} {toRemove.LastName}";
            }
            else
            {
                return "Student not found";
            }

        }

        public string GetSubjectInfo(string subject)
        {
            int counter = 0;

            foreach (Student student in Students)
            {
                if (student.Subject == subject)
                {
                    counter++;
                    break;
                }
            }

            if (counter > 0)
            {
                StringBuilder result = new StringBuilder();

                result.AppendLine($"Subject: {subject}");
                result.AppendLine("Students:");

                foreach (var student in Students.Where(student => student.Subject == subject))
                {
                    result.AppendLine($"{student.FirstName} {student.LastName}");
                }

                return result.ToString().TrimEnd();
            }

            else
            {
                return "No students enrolled for the subject";
            }
        }

        public string GetStudentsCount()
        {
            return $"{Students.Count}";
        }

        public Student GetStudent(string firstName, string lastName)
        {
            Student student = Students.FirstOrDefault(
                x => x.FirstName == firstName
                && x.LastName == lastName);
            return student;
        }
    }
}