using CommunityToolkit.Mvvm.ComponentModel;
using CommunityToolkit.Mvvm.Input;
using LehrerApp.Core.Interfaces;
using LehrerApp.Core.Models;
using System.Collections.ObjectModel;

namespace LehrerApp.Desktop.ViewModels.Students;

public partial class StudentListViewModel : ObservableObject
{
    private readonly IStudentRepository _students;
    public Action<Guid>? OnNavigateToDetail { get; set; }

    [ObservableProperty] private string _searchText = "";
    [ObservableProperty] private bool _showInactive;
    [ObservableProperty] private StudentListItem? _selectedStudent;

    public ObservableCollection<StudentListItem> Students { get; } = [];

    public StudentListViewModel(IStudentRepository students)
    {
        _students = students;
        LoadStudents();
    }

    partial void OnSearchTextChanged(string value) => LoadStudents();
    partial void OnShowInactiveChanged(bool value) => LoadStudents();
    partial void OnSelectedStudentChanged(StudentListItem? value)
    {
        if (value is not null) OnNavigateToDetail?.Invoke(value.Id);
    }

    public void LoadStudents()
    {
        Students.Clear();
        var all = _students.GetAll(ShowInactive);
        var f = string.IsNullOrWhiteSpace(SearchText) ? all
            : all.Where(s => s.LastName.Contains(SearchText, StringComparison.OrdinalIgnoreCase)
                          || s.FirstName.Contains(SearchText, StringComparison.OrdinalIgnoreCase));
        foreach (var s in f) Students.Add(new StudentListItem(s));
    }

    [RelayCommand] private void AddStudent() { /* TODO */ }
    [RelayCommand] private void Refresh()    => LoadStudents();
}

public class StudentListItem
{
    public Guid Id { get; }
    public string FullName { get; }
    public string DateOfBirth { get; }
    public StudentListItem(Student s)
    {
        Id = s.Id; FullName = s.FullName;
        DateOfBirth = s.DateOfBirth?.ToString("dd.MM.yyyy") ?? "";
    }
}

public partial class StudentDetailViewModel : ObservableObject
{
    private readonly IStudentRepository _students;
    private readonly IEnrollmentRepository _enrollments;
    private readonly IGroupRepository _groups;
    private readonly IDocumentationRepository _docs;

    [ObservableProperty] private Student? _student;
    [ObservableProperty] private string _studentTitle = "";
    [ObservableProperty] private bool _isEditing;
    [ObservableProperty] private string _editFirstName = "";
    [ObservableProperty] private string _editLastName = "";

    public ObservableCollection<EnrollmentEntry> Enrollments { get; } = [];
    public ObservableCollection<DocEntry> Documentation { get; } = [];

    public StudentDetailViewModel(IStudentRepository students,
        IEnrollmentRepository enrollments, IGroupRepository groups,
        IDocumentationRepository docs)
    {
        _students = students; _enrollments = enrollments;
        _groups = groups; _docs = docs;
    }

    public void LoadStudent(Guid id)
    {
        Student = _students.GetById(id);
        if (Student is null) return;
        StudentTitle  = Student.FullName;
        EditFirstName = Student.FirstName;
        EditLastName  = Student.LastName;

        Enrollments.Clear();
        foreach (var e in _enrollments.GetByStudent(Student.Id))
        {
            var g = _groups.GetById(e.GroupId);
            if (g is null) continue;
            Enrollments.Add(new() { SchoolYear = e.SchoolYear, GroupName = g.Name, Subject = g.Subject ?? "" });
        }

        Documentation.Clear();
        foreach (var d in _docs.GetByStudent(Student.Id))
            Documentation.Add(new() { Date = d.Date.ToString("dd.MM.yyyy"), Title = d.Title,
                TypeLabel = d.Type switch
                {
                    DocumentationType.Conversation => "Gespräch",
                    DocumentationType.Incident     => "Vorkommnis",
                    DocumentationType.SupportPlan  => "Förderplan",
                    DocumentationType.Absence      => "Fehlzeit",
                    _ => "",
                },
                IsConfidential = d.IsConfidential });
    }

    [RelayCommand] private void StartEdit() => IsEditing = true;
    [RelayCommand] private void CancelEdit()
    {
        if (Student is null) return;
        EditFirstName = Student.FirstName; EditLastName = Student.LastName;
        IsEditing = false;
    }
    [RelayCommand] private void SaveEdit()
    {
        if (Student is null) return;
        Student.FirstName = EditFirstName; Student.LastName = EditLastName;
        _students.Save(Student);
        StudentTitle = Student.FullName;
        IsEditing = false;
    }
}

public class EnrollmentEntry { public string SchoolYear { get; set; } = ""; public string GroupName { get; set; } = ""; public string Subject { get; set; } = ""; }
public class DocEntry { public string Date { get; set; } = ""; public string Title { get; set; } = ""; public string TypeLabel { get; set; } = ""; public bool IsConfidential { get; set; } }