using System.Numerics;
using ImGuiNET;
using Nexus.Core;
using Nexus.Pathfinding;
using Nexus.Simulator.Config;
using Nexus.Simulator.World;

namespace Nexus.Simulator.Rendering;

public class DebugPanel
{
    private readonly SimConfig _config;
    private readonly SimWorld _world;
    private readonly NavigationController _nav;
    private readonly IReadOnlyList<ISystem> _systems;

    private int _spawnRarity; // 0=Normal, 1=Magic, 2=Rare, 3=Unique

    public DebugPanel(SimConfig config, SimWorld world, NavigationController nav, IReadOnlyList<ISystem> systems)
    {
        _config = config;
        _world = world;
        _nav = nav;
        _systems = systems;
    }

    public void Draw(GameState? state)
    {
        ImGui.Begin("Simulator Controls");

        // Simulation controls
        if (ImGui.CollapsingHeader("Simulation", ImGuiTreeNodeFlags.DefaultOpen))
        {
            var paused = _config.IsPaused;
            if (ImGui.Checkbox("Paused", ref paused))
                _config.IsPaused = paused;
            ImGui.SameLine();
            if (ImGui.Button("Step"))
            {
                _config.IsPaused = false;
            }

            var speed = _config.SpeedMultiplier;
            if (ImGui.SliderFloat("Speed", ref speed, 0.1f, 4f, "%.1fx"))
                _config.SpeedMultiplier = speed;

            if (ImGui.Button("Regenerate Terrain"))
                _world.RegenerateTerrain();
        }

        // Player stats
        if (ImGui.CollapsingHeader("Player", ImGuiTreeNodeFlags.DefaultOpen))
        {
            var player = _world.Player;
            ImGui.Text($"Position: ({player.Position.X:F0}, {player.Position.Y:F0})");

            var hpPct = player.MaxHealth > 0 ? (float)player.Health / player.MaxHealth : 0;
            ImGui.ProgressBar(hpPct, new Vector2(-1, 0), $"HP: {player.Health}/{player.MaxHealth}");

            var manaPct = player.MaxMana > 0 ? (float)player.Mana / player.MaxMana : 0;
            ImGui.ProgressBar(manaPct, new Vector2(-1, 0), $"MP: {player.Mana}/{player.MaxMana}");
        }

        // Enemy stats
        if (ImGui.CollapsingHeader("Enemies", ImGuiTreeNodeFlags.DefaultOpen))
        {
            var enemies = _world.Enemies.ToArray(); // snapshot — list mutated by SimPoller thread
            var alive = enemies.Count(e => e.IsAlive);
            var dead = enemies.Count(e => !e.IsAlive);
            var chasing = enemies.Count(e => e.AiState == EnemyAiState.Chasing);
            var attacking = enemies.Count(e => e.AiState == EnemyAiState.Attacking);

            ImGui.Text($"Total: {enemies.Length}  Alive: {alive}  Dead: {dead}");
            ImGui.Text($"Chasing: {chasing}  Attacking: {attacking}");

            ImGui.Separator();
            ImGui.Text("Spawn Enemy:");
            string[] rarities = ["Normal", "Magic", "Rare", "Unique"];
            ImGui.Combo("Rarity", ref _spawnRarity, rarities, rarities.Length);
            if (ImGui.Button("Spawn at Player"))
            {
                var rarity = (MonsterRarity)_spawnRarity;
                var offset = new Vector2(200, 0);
                _world.SpawnEnemyAt(_world.Player.Position + offset, rarity);
            }
        }

        // Navigation
        if (ImGui.CollapsingHeader("Navigation"))
        {
            ImGui.Text($"Mode: {_nav.Mode}");
            ImGui.Text($"Status: {_nav.Status}");
            ImGui.Text($"Direction: {(_nav.DesiredDirection.HasValue ? $"({_nav.DesiredDirection.Value.X:F2}, {_nav.DesiredDirection.Value.Y:F2})" : "none")}");

            var path = _nav.CurrentPath;
            ImGui.Text($"Path: {path?.Count ?? 0} waypoints");
            ImGui.Text($"Exploration complete: {_nav.IsExplorationComplete}");
        }

        // Systems
        if (ImGui.CollapsingHeader("Systems"))
        {
            foreach (var sys in _systems)
            {
                var enabled = sys.IsEnabled;
                if (ImGui.Checkbox(sys.Name, ref enabled))
                    sys.IsEnabled = enabled;
            }
        }

        // Threat info
        if (state is not null && ImGui.CollapsingHeader("Threat"))
        {
            ImGui.Text($"Danger: {state.Danger}");
            var threats = state.Threats;
            ImGui.Text($"Close: {threats.CloseRange}  Mid: {threats.MidRange}  Far: {threats.FarRange}");
            ImGui.Text($"Closest: {threats.ClosestDistance:F0}");
            ImGui.Text($"Has Rare/Unique: {threats.HasRareOrUnique}");
        }

        // Action queue
        if (state is not null && ImGui.CollapsingHeader("State"))
        {
            ImGui.Text($"Tick: {state.TickNumber}");
            ImGui.Text($"Entities: {state.Entities.Count}");
            ImGui.Text($"Hostile: {state.HostileMonsters.Count}");
            ImGui.Text($"Nearest: {state.NearestEnemies.Count}");
        }

        ImGui.End();
    }
}