// Kyoo - A portable and vast media library solution.
// Copyright (c) Kyoo.
//
// See AUTHORS.md and LICENSE file in the project root for full license information.
//
// Kyoo is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// any later version.
//
// Kyoo is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Kyoo. If not, see <https://www.gnu.org/licenses/>.

using System.Threading.Tasks;
using Kyoo.Abstractions.Models.Attributes;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Diagnostics.HealthChecks;

namespace Kyoo.Core.Api;

/// <summary>
/// An API endpoint to check the health.
/// </summary>
[Route("health")]
[ApiController]
[ApiDefinition("Health")]
public class Health(HealthCheckService healthCheckService) : BaseApi
{
	/// <summary>
	/// Check if the api is ready to accept requests.
	/// </summary>
	/// <returns>A status indicating the health of the api.</returns>
	[HttpGet]
	[ProducesResponseType(StatusCodes.Status200OK)]
	[ProducesResponseType(StatusCodes.Status503ServiceUnavailable)]
	public async Task<IActionResult> CheckHealth()
	{
		IHeaderDictionary headers = HttpContext.Response.Headers;
		headers.CacheControl = "no-store, no-cache";
		headers.Pragma = "no-cache";
		headers.Expires = "Thu, 01 Jan 1970 00:00:00 GMT";

		HealthReport result = await healthCheckService.CheckHealthAsync();
		return result.Status switch
		{
			HealthStatus.Healthy => Ok(new HealthResult("Healthy")),
			HealthStatus.Unhealthy => Ok(new HealthResult("Unstable")),
			HealthStatus.Degraded => StatusCode(StatusCodes.Status503ServiceUnavailable),
			_ => StatusCode(StatusCodes.Status500InternalServerError),
		};
	}

	/// <summary>
	/// The result of a health operation.
	/// </summary>
	public record HealthResult(string Status);
}