feat: add queries for group

Application/Cqrs/Group/Queries/GetGroupDetails/GetGroupInfoQuery.cs

@@ -0,0 +1,8 @@
+using MediatR;
+
+namespace Mirea.Api.DataAccess.Application.Cqrs.Group.Queries.GetGroupDetails;
+
+public class GetGroupInfoQuery : IRequest<GroupInfoVm>
+{
+    public required int Id { get; set; }
+}

Application/Cqrs/Group/Queries/GetGroupDetails/GetGroupInfoQueryHandler.cs

@@ -0,0 +1,28 @@
+using MediatR;
+using Microsoft.EntityFrameworkCore;
+using Mirea.Api.DataAccess.Application.Common.Exceptions;
+using Mirea.Api.DataAccess.Application.Interfaces.DbContexts.Schedule;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace Mirea.Api.DataAccess.Application.Cqrs.Group
+    .Queries.GetGroupDetails;
+
+public class GetGroupInfoQueryHandler(IGroupDbContext dbContext) : IRequestHandler<GetGroupInfoQuery, GroupInfoVm>
+{
+    public async Task<GroupInfoVm> Handle(GetGroupInfoQuery request, CancellationToken cancellationToken)
+    {
+        var discipline = await dbContext.Groups
+            .Include(g => g.Faculty)
+            .FirstOrDefaultAsync(g => g.Id == request.Id, cancellationToken)
+                         ?? throw new NotFoundException(typeof(Domain.Schedule.Group), request.Id);
+
+        return new GroupInfoVm()
+        {
+            Id = discipline.Id,
+            Name = discipline.Name,
+            Faculty = discipline.Faculty?.Name,
+            FacultyId = discipline.FacultyId
+        };
+    }
+}

Application/Cqrs/Group/Queries/GetGroupDetails/GroupInfoVm.cs

@@ -0,0 +1,27 @@
+namespace Mirea.Api.DataAccess.Application.Cqrs.Group.Queries.GetGroupDetails;
+
+/// <summary>
+/// Represents groups.
+/// </summary>
+public class GroupInfoVm
+{
+    /// <summary>
+    /// The unique identifier for the group.
+    /// </summary>
+    public int Id { get; set; }
+
+    /// <summary>
+    /// The name of the group.
+    /// </summary>
+    public required string Name { get; set; }
+
+    /// <summary>
+    /// The faculty name for the group.
+    /// </summary>
+    public string? Faculty { get; set; }
+
+    /// <summary>
+    /// The faculty identifier for the group.
+    /// </summary>
+    public int? FacultyId { get; set; }
+}

Application/Cqrs/Group/Queries/GetGroupList/GetGroupListQuery.cs

@@ -0,0 +1,9 @@
+using MediatR;
+
+namespace Mirea.Api.DataAccess.Application.Cqrs.Group.Queries.GetGroupList;
+
+public class GetGroupListQuery : IRequest<GroupListVm>
+{
+    public int? Page { get; set; }
+    public int? PageSize { get; set; }
+}

Application/Cqrs/Group/Queries/GetGroupList/GetGroupListQueryHandler.cs

@@ -0,0 +1,31 @@
+using MediatR;
+using Microsoft.EntityFrameworkCore;
+using Mirea.Api.DataAccess.Application.Interfaces.DbContexts.Schedule;
+using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace Mirea.Api.DataAccess.Application.Cqrs.Group.Queries.GetGroupList;
+
+public class GetGroupListQueryHandler(IGroupDbContext dbContext) : IRequestHandler<GetGroupListQuery, GroupListVm>
+{
+    public async Task<GroupListVm> Handle(GetGroupListQuery request, CancellationToken cancellationToken)
+    {
+        var dtos = dbContext.Groups.OrderBy(g => g.Id).Select(g => new GroupLookupDto()
+        {
+            Id = g.Id,
+            Name = g.Name,
+            FacultyId = g.FacultyId
+        });
+
+        if (request is { PageSize: not null, Page: not null })
+            dtos = dtos.Skip(request.Page.Value * request.PageSize.Value).Take(request.PageSize.Value);
+
+        var result = await dtos.ToListAsync(cancellationToken);
+
+        return new GroupListVm
+        {
+            Groups = result
+        };
+    }
+}

Application/Cqrs/Group/Queries/GetGroupList/GroupListVm.cs

@@ -0,0 +1,14 @@
+using System.Collections.Generic;
+
+namespace Mirea.Api.DataAccess.Application.Cqrs.Group.Queries.GetGroupList;
+
+/// <summary>
+/// Represents a view model containing multiple groups name.
+/// </summary>
+public class GroupListVm
+{
+    /// <summary>
+    /// The list of groups.
+    /// </summary>
+    public IList<GroupLookupDto> Groups { get; set; } = new List<GroupLookupDto>();
+}

Application/Cqrs/Group/Queries/GetGroupList/GroupLookupDto.cs

@@ -0,0 +1,22 @@
+namespace Mirea.Api.DataAccess.Application.Cqrs.Group.Queries.GetGroupList;
+
+/// <summary>
+/// Represents groups.
+/// </summary>
+public class GroupLookupDto
+{
+    /// <summary>
+    /// The unique identifier for the group.
+    /// </summary>
+    public int Id { get; set; }
+
+    /// <summary>
+    /// The name of the group.
+    /// </summary>
+    public required string Name { get; set; }
+
+    /// <summary>
+    /// The faculty identifier for the group.
+    /// </summary>
+    public int? FacultyId { get; set; }
+}