using System;
using System.Collections.Generic;
using System.Numerics;
using System.Threading;
using System.Threading.Tasks;
using Dalamud.Plugin;
using Dalamud.Plugin.Ipc;
using Dalamud.Plugin.Ipc.Exceptions;
using Microsoft.Extensions.Logging;
using Newtonsoft.Json;

namespace Questionable.External;

internal sealed class WigglyNavIpc
{
	private readonly ILogger<WigglyNavIpc> _logger;

	private readonly ICallGateSubscriber<(int, int)> _apiVersion;

	private readonly ICallGateSubscriber<NavStatus> _status;

	private readonly ICallGateSubscriber<bool> _rebuild;

	private readonly ICallGateSubscriber<PathfindQuery, CancellationToken, Task<string>> _pathfind;

	private readonly ICallGateSubscriber<MoveCommand, bool> _move;

	private readonly ICallGateSubscriber<object> _stop;

	private readonly ICallGateSubscriber<bool> _isRunning;

	private readonly ICallGateSubscriber<List<Vector3>> _waypoints;

	private readonly ICallGateSubscriber<Vector3, float, bool, Vector3?> _floorPoint;

	private readonly ICallGateSubscriber<Vector3, float, Vector3?> _nearestPoint;

	private int _outstandingPathfinds;

	public bool IsNavmeshAvailable => TryGetApiVersion().HasValue;

	public bool IsReady => GetStatus()?.Ready ?? false;

	public bool IsPathRunning => Guarded(() => _isRunning.InvokeFunc(), fallback: false);

	public bool IsPathfindInProgress => Volatile.Read(in _outstandingPathfinds) > 0;

	public int NumQueuedPathfindRequests => Math.Max(0, Volatile.Read(in _outstandingPathfinds) - 1);

	public WigglyNavIpc(IDalamudPluginInterface pluginInterface, ILogger<WigglyNavIpc> logger)
	{
		_logger = logger;
		_apiVersion = pluginInterface.GetIpcSubscriber<(int, int)>("WigglyNav.ApiVersion");
		_status = pluginInterface.GetIpcSubscriber<NavStatus>("WigglyNav.V1.Nav.Status");
		_rebuild = pluginInterface.GetIpcSubscriber<bool>("WigglyNav.V1.Nav.Rebuild");
		_pathfind = pluginInterface.GetIpcSubscriber<PathfindQuery, CancellationToken, Task<string>>("WigglyNav.V1.Pathfind");
		_move = pluginInterface.GetIpcSubscriber<MoveCommand, bool>("WigglyNav.V1.Path.Move");
		_stop = pluginInterface.GetIpcSubscriber<object>("WigglyNav.V1.Path.Stop");
		_isRunning = pluginInterface.GetIpcSubscriber<bool>("WigglyNav.V1.Path.IsRunning");
		_waypoints = pluginInterface.GetIpcSubscriber<List<Vector3>>("WigglyNav.V1.Path.Waypoints");
		_floorPoint = pluginInterface.GetIpcSubscriber<Vector3, float, bool, Vector3?>("WigglyNav.V1.Query.FloorPoint");
		_nearestPoint = pluginInterface.GetIpcSubscriber<Vector3, float, Vector3?>("WigglyNav.V1.Query.NearestPoint");
	}

	private static T Guarded<T>(Func<T> invoke, T fallback = default(T))
	{
		try
		{
			return invoke();
		}
		catch (IpcError)
		{
			return fallback;
		}
	}

	public (int Major, int Minor)? TryGetApiVersion()
	{
		return Guarded((Func<(int, int)?>)(() => _apiVersion.InvokeFunc()), ((int, int)?)null);
	}

	public int GetBuildProgress()
	{
		NavStatus status = GetStatus();
		if (status == null)
		{
			return 0;
		}
		if (status.TilesTotal > 0)
		{
			return Math.Clamp(status.TilesBuilt * 100 / status.TilesTotal, 0, 100);
		}
		if (!status.Ready)
		{
			return 0;
		}
		return 100;
	}

	public async Task<PathfindResult> Pathfind(Vector3 from, Vector3 to, bool fly, float tolerance, CancellationToken cancellationToken)
	{
		Interlocked.Increment(ref _outstandingPathfinds);
		try
		{
			PathfindQuery query = new PathfindQuery(from, to, fly, tolerance);
			Task<string> task = Guarded(() => _pathfind.InvokeFunc(query, cancellationToken));
			if (task == null)
			{
				_logger.LogWarning("Could not pathfind via WigglyNav, the IPC gate is unavailable");
				return EmptyPathfindResult();
			}
			string value = await task.ConfigureAwait(continueOnCapturedContext: false);
			try
			{
				PathfindResult pathfindResult = JsonConvert.DeserializeObject<PathfindResult>(value);
				if ((object)pathfindResult == null || pathfindResult.Waypoints == null)
				{
					_logger.LogWarning("WigglyNav pathfind answered a payload with no waypoint list, treating as no path");
					return EmptyPathfindResult();
				}
				return pathfindResult;
			}
			catch (JsonException exception)
			{
				_logger.LogWarning(exception, "WigglyNav pathfind answered malformed JSON, treating as no path");
				return EmptyPathfindResult();
			}
		}
		finally
		{
			Interlocked.Decrement(ref _outstandingPathfinds);
		}
	}

	public bool MoveTo(List<Vector3> waypoints, bool fly, float arrivalTolerance)
	{
		Stop();
		MoveCommand command = new MoveCommand(waypoints, fly, arrivalTolerance);
		return Guarded(() => _move.InvokeFunc(command), fallback: false);
	}

	public void Stop()
	{
		Guarded(delegate
		{
			_stop.InvokeAction();
			return true;
		}, fallback: false);
	}

	public List<Vector3> GetWaypoints()
	{
		return Guarded(() => _waypoints.InvokeFunc()) ?? new List<Vector3>();
	}

	public Vector3? GetPointOnFloor(Vector3 position, bool unlandable, float halfExtentXZ)
	{
		return Guarded(() => _floorPoint.InvokeFunc(position, halfExtentXZ, unlandable));
	}

	public Vector3? FindNearestMeshPoint(Vector3 position, float halfExtentXZ, float halfExtentY)
	{
		return Guarded(() => _nearestPoint.InvokeFunc(position, MathF.Max(halfExtentXZ, halfExtentY)));
	}

	public Vector3? FindNearestReachableMeshPoint(Vector3 position, float halfExtentXZ, float halfExtentY)
	{
		return FindNearestMeshPoint(position, halfExtentXZ, halfExtentY);
	}

	public void Reload()
	{
		Rebuild();
	}

	public void Rebuild()
	{
		if (!Guarded(() => _rebuild.InvokeFunc(), fallback: false))
		{
			_logger.LogWarning("Could not rebuild navmesh via WigglyNav, the request was refused or the gate is unavailable");
		}
	}

	private NavStatus? GetStatus()
	{
		return Guarded(() => _status.InvokeFunc());
	}

	private static PathfindResult EmptyPathfindResult()
	{
		return new PathfindResult(new List<Vector3>(), IsPartial: false, "None", 0f);
	}
}