ContactsApp/Controllers/ContactController.cs

using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Diagnostics.HealthChecks;
using System.Text.Json;

namespace ContactsApp
{
    [ApiController]
    [Route("api/contacts")]
    public class ContactController(IContactRepository repository) : ControllerBase
    {
        [HttpGet]
        public ActionResult<IEnumerable<Contact>> GetAll()
        {
            var contacts = repository.GetAll().ToList();
            return Ok(contacts);
        }

        [HttpPost]
        public ActionResult<Contact> Create([FromBody] Contact contact)
        {
            repository.AddContact(contact);
            return Ok(contact);
        }

        [HttpGet("{id:Guid}")]
        public ActionResult<Contact> GetById(Guid id)
        {
            var contact = repository.GetContactById(id);
            if (contact == null)
                return NotFound();

            return Ok(contact);
        }
        [HttpPost("{id:Guid}")]
        public ActionResult Update(Guid id, [FromBody] Contact contact)
        {
            repository.UpdateContact(id, contact);
            return Ok();
        }

        [HttpDelete("{id:Guid}")]
        public ActionResult Delete(Guid id)
        {
            var contact = repository.GetContactById(id);
            if (contact == null)
                return NotFound();

            repository.DeleteContact(id);
            return Ok();
        }

        [HttpPost("upload")]
        public async Task<IActionResult> Upload(IFormFile file)
        {
            if (file == null || file.Length == 0)
                return BadRequest("Ôàéë ïóñòîé.");

            using var stream = new MemoryStream();
            await file.CopyToAsync(stream);
            string json = System.Text.Encoding.UTF8.GetString(stream.ToArray());

            try
            {
                repository.LoadJSON(json); // ðåïîçèòîðèé ñàì ïàðñèò JSON è îáíîâëÿåò ñïèñîê
            }
            catch (Exception ex)
            {
                return BadRequest("Îøèáêà ïðè îáðàáîòêå JSON: " + ex.Message);
            }

            return Ok("Êîíòàêòû óñïåøíî çàãðóæåíû.");
        }

        [HttpGet("download")]
        public IActionResult Download()
        {
            string json = repository.SaveJSON(); // ðåïîçèòîðèé ôîðìèðóåò JSON ñòðîêó
            byte[] bytes = System.Text.Encoding.UTF8.GetBytes(json);

            return File(
                bytes,
                "application/json",
                "contacts.json"
            );
        }

    }
}