using System;
using System.Threading;
using System.Threading.Tasks;
using Jellyfin.Plugin.JRay.Models;
using Jellyfin.Plugin.JRay.Services.Interfaces;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;

namespace Jellyfin.Plugin.JRay.Controllers;

/// <summary>
/// Accepts scene-actor-extraction "truth" data pushed directly by a remote
/// extraction worker, for servers that cannot run the extraction pipeline
/// locally. See SPEC.md.
/// </summary>
[ApiController]
[Route("Plugins/JRay/Items/{itemId}/Truth")]
[Authorize(Roles = "Administrator")]
public class TruthController : ControllerBase
{
    private const int SupportedSchemaVersion = 1;

    private readonly IManagedTruthStore _managedTruthStore;
    private readonly ITruthDataService _truthDataService;

    /// <summary>
    /// Initializes a new instance of the <see cref="TruthController"/> class.
    /// </summary>
    /// <param name="managedTruthStore">The managed truth store.</param>
    /// <param name="truthDataService">The truth data service.</param>
    public TruthController(IManagedTruthStore managedTruthStore, ITruthDataService truthDataService)
    {
        _managedTruthStore = managedTruthStore;
        _truthDataService = truthDataService;
    }

    /// <summary>
    /// Uploads (creates or replaces) the truth data for an item.
    /// </summary>
    /// <param name="itemId">The Jellyfin item id.</param>
    /// <param name="truth">The truth file contents.</param>
    /// <param name="cancellationToken">Cancellation token.</param>
    /// <returns>204 on success, or 400 if the schema version is unsupported.</returns>
    [HttpPut]
    [ProducesResponseType(StatusCodes.Status204NoContent)]
    [ProducesResponseType(StatusCodes.Status400BadRequest)]
    public async Task<IActionResult> PutTruth(Guid itemId, [FromBody] TruthFile truth, CancellationToken cancellationToken)
    {
        if (truth.SchemaVersion != SupportedSchemaVersion)
        {
            return BadRequest($"Unsupported schema_version {truth.SchemaVersion}; expected {SupportedSchemaVersion}.");
        }

        await _managedTruthStore.SaveAsync(itemId, truth, cancellationToken).ConfigureAwait(false);
        _truthDataService.Invalidate(itemId);

        return NoContent();
    }

    /// <summary>
    /// Removes any managed truth data for an item. The item falls back to
    /// its sidecar truth file (if any) on subsequent reads.
    /// </summary>
    /// <param name="itemId">The Jellyfin item id.</param>
    /// <returns>204, whether or not managed data existed.</returns>
    [HttpDelete]
    [ProducesResponseType(StatusCodes.Status204NoContent)]
    public IActionResult DeleteTruth(Guid itemId)
    {
        _managedTruthStore.Delete(itemId);
        _truthDataService.Invalidate(itemId);

        return NoContent();
    }
}