using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;

using MongoDB.Entities;

using PrivaPub.ClientModels;
using PrivaPub.ClientModels.Admin;
using PrivaPub.Domain.Instance;
using PrivaPub.Domain.Moderation;
using PrivaPub.Extensions;
using PrivaPub.Models;
using PrivaPub.Models.Social;
using PrivaPub.Models.User;

namespace PrivaPub.Controllers.ClientToServer
{
	[ApiController,
		Route("clientapi/moderator"),
		Authorize(Policy = Policies.IsModerator)]
	public class ModeratorController : ControllerBase
	{
		const int MaxLogPage = 100;

		readonly IInstanceSettings _settings;
		readonly IModerationLog _log;

		public ModeratorController(IInstanceSettings settings, IModerationLog log)
		{
			_settings = settings;
			_log = log;
		}

		[HttpGet, Route("/clientapi/moderator/reports")]
		public async Task<IActionResult> Reports([FromQuery] bool resolved, CancellationToken token)
		{
			var rules = _settings.Current.Rules.ToDictionary(r => r.Id, r => r.Text ?? string.Empty);
			return Ok((await DB.Default.Find<Report>().Match(r => r.IsResolved == resolved).Sort(r => r.ID, Order.Descending).Limit(100).ExecuteAsync(token))
				.Select(r => new ViewReport
				{
					ID = r.ID,
					Reporter = r.ReporterAvatarId != default ? "local" : r.ReporterActorURI,
					TargetAccountId = r.TargetAccountId,
					TargetActorURI = r.TargetActorURI,
					PostIds = r.PostIds,
					ObjectURIs = r.ObjectURIs,
					Category = r.Category,
					RuleIds = r.RuleIds ?? new(),
					Rules = (r.RuleIds ?? new()).Select(id => rules.GetValueOrDefault(id, string.Empty)).ToList(),
					Comment = r.Comment,
					Forwarded = r.Forwarded,
					IsResolved = r.IsResolved,
					CreatedAt = r.CreatedAt,
					ResolvedAt = r.ResolvedAt,
					RemoteResolvedAt = r.RemoteResolvedAt,
					RemoteResolvedBy = r.RemoteResolvedBy
				}));
		}

		[HttpPost, Route("/clientapi/moderator/reports/{id}/resolve")]
		public async Task<IActionResult> Resolve(string id, CancellationToken token)
		{
			var by = User.GetUserId();
			var result = await DB.Default.Update<Report>().MatchID(id)
				.Modify(r => r.IsResolved, true)
				.Modify(r => r.ResolvedAt, DateTime.UtcNow)
				.Modify(r => r.ResolvedBy, by)
				.ExecuteAsync(token);
			if (result.MatchedCount == 0)
				return NotFound();
			var report = await DB.Default.Find<Report>().MatchID(id).ExecuteFirstAsync(token);
			await _log.Write(by, AdminActions.ReportResolve, AdminTargets.Report, id, report?.Category, reportId: id, token: token);
			return Ok();
		}

		// The staff's log, newest first, a page at a time (before: the last id of the page before). Administrators read all
		// of it; a moderator who isn't one reads what isn't about a login, and who acted only when it was the command line or
		// themselves.
		[HttpGet, Route("/clientapi/moderator/log")]
		public async Task<IActionResult> Log([FromQuery] string before, [FromQuery] int limit = 50, CancellationToken token = default)
		{
			var me = await DB.Default.Find<RootUser>().MatchID(User.GetUserId()).ExecuteFirstAsync(token);
			if (me is not { IsBanned: false, DeletedAt: null } || !me.Policies.Contains(Policies.IsModerator))
				return Forbid();
			var admin = me.Policies.Contains(Policies.IsAdmin);
			limit = Math.Clamp(limit, 1, MaxLogPage);
			var query = DB.Default.Find<AdminAction>();
			if (!string.IsNullOrEmpty(before))
			{
				if (!MongoDB.Bson.ObjectId.TryParse(before, out _))
					return BadRequest();
				query.Match(f => f.Lt(a => a.ID, before));
			}
			if (!admin)
				query.Match(a => a.TargetKind != AdminTargets.Root);
			var actions = await query.Sort(a => a.ID, Order.Descending).Limit(limit).ExecuteAsync(token);
			var actorIds = actions.Select(a => a.ByRootId).Where(id => id != default && id != AdminAction.Cli).Distinct().ToList();
			var names = admin && actorIds.Count > 0
				? (await DB.Default.Find<RootUser>().Match(u => actorIds.Contains(u.ID)).Project(u => u.Include(x => x.UserName)).ExecuteAsync(token))
					.ToDictionary(u => u.ID, u => u.UserName)
				: new Dictionary<string, string>();
			return Ok(new ViewAdminActionsPage
			{
				Items = actions.Select(a => new ViewAdminAction
				{
					Id = a.ID,
					At = a.At,
					By = a.ByRootId == AdminAction.Cli ? AdminAction.Cli
						: a.ByRootId == default ? default
						: admin ? names.GetValueOrDefault(a.ByRootId, a.ByRootId)
						: a.ByRootId == me.ID ? me.UserName
						: default,
					ByYou = a.ByRootId == me.ID,
					Action = a.Action,
					TargetKind = a.TargetKind,
					TargetId = a.TargetId,
					TargetLabel = a.TargetLabel,
					ReportId = a.ReportId,
					Note = a.Note
				}).ToList(),
				Next = actions.Count == limit ? actions[^1].ID : default
			});
		}
	}
}