using System.Collections.Generic;
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>
/// Manages the prioritise/ignore rules that shape the work-discovery API
/// (<c>GET /Plugins/JRay/Tasks/Pending</c>). Rules can target a genre, a
/// series, or a single item; setting a rule for a target that already has one
/// replaces it, so a target can never be both prioritised and ignored.
/// </summary>
[ApiController]
[Route("Plugins/JRay/Policy")]
[Authorize(Roles = "Administrator")]
public class PolicyController : ControllerBase
{
    private readonly IMediaPolicyStore _policyStore;

    /// <summary>
    /// Initializes a new instance of the <see cref="PolicyController"/> class.
    /// </summary>
    /// <param name="policyStore">The media policy store.</param>
    public PolicyController(IMediaPolicyStore policyStore)
    {
        _policyStore = policyStore;
    }

    /// <summary>
    /// Gets all configured prioritise/ignore rules.
    /// </summary>
    /// <returns>The current rules.</returns>
    [HttpGet("Rules")]
    [ProducesResponseType(StatusCodes.Status200OK)]
    public ActionResult<IReadOnlyList<MediaPolicyRule>> GetRules()
    {
        return Ok(_policyStore.GetRules());
    }

    /// <summary>
    /// Adds or replaces a rule. If a rule already exists for the same scope
    /// and value, its action is updated.
    /// </summary>
    /// <param name="rule">The rule to set.</param>
    /// <returns>204 on success, or 400 if the rule has no value.</returns>
    [HttpPut("Rules")]
    [ProducesResponseType(StatusCodes.Status204NoContent)]
    [ProducesResponseType(StatusCodes.Status400BadRequest)]
    public IActionResult SetRule([FromBody] MediaPolicyRule rule)
    {
        if (rule is null || string.IsNullOrWhiteSpace(rule.Value))
        {
            return BadRequest("A rule must have a non-empty value.");
        }

        _policyStore.SetRule(rule);
        return NoContent();
    }

    /// <summary>
    /// Removes the rule matching the given scope and value.
    /// </summary>
    /// <param name="scope">The scope of the rule to remove.</param>
    /// <param name="value">The value of the rule to remove.</param>
    /// <returns>204 whether or not a matching rule existed.</returns>
    [HttpDelete("Rules")]
    [ProducesResponseType(StatusCodes.Status204NoContent)]
    public IActionResult RemoveRule([FromQuery] PolicyScope scope, [FromQuery] string value)
    {
        _policyStore.RemoveRule(scope, value ?? string.Empty);
        return NoContent();
    }
}