using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Threading.Tasks;
using Jellyfin.Api.Constants;
using MediaBrowser.Common.Updates;
using MediaBrowser.Controller.Configuration;
using MediaBrowser.Model.Updates;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;

namespace Jellyfin.Api.Controllers
{
    /// <summary>
    /// Package Controller.
    /// </summary>
    [Route("")]
    [Authorize(Policy = Policies.DefaultAuthorization)]
    public class PackageController : BaseJellyfinApiController
    {
        private readonly IInstallationManager _installationManager;
        private readonly IServerConfigurationManager _serverConfigurationManager;

        /// <summary>
        /// Initializes a new instance of the <see cref="PackageController"/> class.
        /// </summary>
        /// <param name="installationManager">Instance of the <see cref="IInstallationManager"/> interface.</param>
        /// <param name="serverConfigurationManager">Instance of the <see cref="IServerConfigurationManager"/> interface.</param>
        public PackageController(IInstallationManager installationManager, IServerConfigurationManager serverConfigurationManager)
        {
            _installationManager = installationManager;
            _serverConfigurationManager = serverConfigurationManager;
        }

        /// <summary>
        /// Gets a package by name or assembly GUID.
        /// </summary>
        /// <param name="name">The name of the package.</param>
        /// <param name="assemblyGuid">The GUID of the associated assembly.</param>
        /// <response code="200">Package retrieved.</response>
        /// <returns>A <see cref="PackageInfo"/> containing package information.</returns>
        [HttpGet("Packages/{name}")]
        [ProducesResponseType(StatusCodes.Status200OK)]
        public async Task<ActionResult<PackageInfo>> GetPackageInfo(
            [FromRoute, Required] string name,
            [FromQuery] Guid? assemblyGuid)
        {
            var packages = await _installationManager.GetAvailablePackages().ConfigureAwait(false);
            var result = _installationManager.FilterPackages(
                    packages,
                    name,
                    assemblyGuid ?? default)
                .FirstOrDefault();

            if (result is null)
            {
                return NotFound();
            }

            return result;
        }

        /// <summary>
        /// Gets available packages.
        /// </summary>
        /// <response code="200">Available packages returned.</response>
        /// <returns>An <see cref="PackageInfo"/> containing available packages information.</returns>
        [HttpGet("Packages")]
        [ProducesResponseType(StatusCodes.Status200OK)]
        public async Task<IEnumerable<PackageInfo>> GetPackages()
        {
            IEnumerable<PackageInfo> packages = await _installationManager.GetAvailablePackages().ConfigureAwait(false);

            return packages;
        }

        /// <summary>
        /// Installs a package.
        /// </summary>
        /// <param name="name">Package name.</param>
        /// <param name="assemblyGuid">GUID of the associated assembly.</param>
        /// <param name="version">Optional version. Defaults to latest version.</param>
        /// <param name="repositoryUrl">Optional. Specify the repository to install from.</param>
        /// <response code="204">Package found.</response>
        /// <response code="404">Package not found.</response>
        /// <returns>A <see cref="NoContentResult"/> on success, or a <see cref="NotFoundResult"/> if the package could not be found.</returns>
        [HttpPost("Packages/Installed/{name}")]
        [ProducesResponseType(StatusCodes.Status204NoContent)]
        [ProducesResponseType(StatusCodes.Status404NotFound)]
        [Authorize(Policy = Policies.RequiresElevation)]
        public async Task<ActionResult> InstallPackage(
            [FromRoute, Required] string name,
            [FromQuery] Guid? assemblyGuid,
            [FromQuery] string? version,
            [FromQuery] string? repositoryUrl)
        {
            var packages = await _installationManager.GetAvailablePackages().ConfigureAwait(false);
            if (!string.IsNullOrEmpty(repositoryUrl))
            {
                packages = packages.Where(p => p.Versions.Any(q => q.RepositoryUrl.Equals(repositoryUrl, StringComparison.OrdinalIgnoreCase)))
                    .ToList();
            }

            var package = _installationManager.GetCompatibleVersions(
                    packages,
                    name,
                    assemblyGuid ?? Guid.Empty,
                    specificVersion: string.IsNullOrEmpty(version) ? null : Version.Parse(version))
                .FirstOrDefault();

            if (package is null)
            {
                return NotFound();
            }

            await _installationManager.InstallPackage(package).ConfigureAwait(false);

            return NoContent();
        }

        /// <summary>
        /// Cancels a package installation.
        /// </summary>
        /// <param name="packageId">Installation Id.</param>
        /// <response code="204">Installation cancelled.</response>
        /// <returns>A <see cref="NoContentResult"/> on successfully cancelling a package installation.</returns>
        [HttpDelete("Packages/Installing/{packageId}")]
        [Authorize(Policy = Policies.RequiresElevation)]
        [ProducesResponseType(StatusCodes.Status204NoContent)]
        public ActionResult CancelPackageInstallation(
            [FromRoute, Required] Guid packageId)
        {
            _installationManager.CancelInstallation(packageId);
            return NoContent();
        }

        /// <summary>
        /// Gets all package repositories.
        /// </summary>
        /// <response code="200">Package repositories returned.</response>
        /// <returns>An <see cref="OkResult"/> containing the list of package repositories.</returns>
        [HttpGet("Repositories")]
        [ProducesResponseType(StatusCodes.Status200OK)]
        public ActionResult<IEnumerable<RepositoryInfo>> GetRepositories()
        {
            return Ok(_serverConfigurationManager.Configuration.PluginRepositories.AsEnumerable());
        }

        /// <summary>
        /// Sets the enabled and existing package repositories.
        /// </summary>
        /// <param name="repositoryInfos">The list of package repositories.</param>
        /// <response code="204">Package repositories saved.</response>
        /// <returns>A <see cref="NoContentResult"/>.</returns>
        [HttpPost("Repositories")]
        [Authorize(Policy = Policies.RequiresElevation)]
        [ProducesResponseType(StatusCodes.Status204NoContent)]
        public ActionResult SetRepositories([FromBody, Required] RepositoryInfo[] repositoryInfos)
        {
            _serverConfigurationManager.Configuration.PluginRepositories = repositoryInfos;
            _serverConfigurationManager.SaveConfiguration();
            return NoContent();
        }
    }
}
