using System.Text.Json;
using Ananta.Server.Configuration;
using Ananta.Server.Protocol.Client4229938;

namespace Ananta.Server.Handlers.Game;

/// <summary>
/// Persists per-player vehicle tuning (bought parts / suits / session unlocks) to
/// save/vehicles/&lt;pid&gt;.json so purchases survive a server restart.
/// </summary>
internal static class VehicleTuningStore
{
    private static string DirFor(ulong pid)
    {
        string baseDir;
        try { baseDir = PrivateServerConfigStore.ProjectRoot; }
        catch { baseDir = AppContext.BaseDirectory; }
        return Path.Combine(baseDir, "save", "vehicles");
    }

    private static string FileFor(ulong pid) => Path.Combine(DirFor(pid), $"{pid}.json");

    public static void Save(ulong pid, WorldEntryState world)
    {
        try
        {
            var dir = DirFor(pid);
            Directory.CreateDirectory(dir);
            var dto = new TuningDto
            {
                Unlocked = world.SessionUnlockedVehicleConfigs.ToList(),
                Parts = world.VehiclePartsByConfig.ToDictionary(
                    kv => kv.Key,
                    kv => kv.Value.Select(p => new PartDto { Type = p.Type, PartId = p.PartId }).ToList()),
                Suits = new Dictionary<uint, uint>(world.VehicleSuitByConfig),
            };
            var json = JsonSerializer.Serialize(dto, new JsonSerializerOptions { WriteIndented = true });
            File.WriteAllText(FileFor(pid), json);
        }
        catch (Exception ex)
        {
            Console.WriteLine($"[TUNING] save failed pid={pid}: {ex.Message}");
        }
    }

    /// <summary>Loads saved tuning into the (fresh) world state — called on world entry.</summary>
    public static void LoadInto(ulong pid, WorldEntryState world)
    {
        try
        {
            var path = FileFor(pid);
            if (!File.Exists(path))
                return;
            var dto = JsonSerializer.Deserialize<TuningDto>(File.ReadAllText(path));
            if (dto is null)
                return;
            lock (world.SyncRoot)
            {
                foreach (var id in dto.Unlocked)
                    world.SessionUnlockedVehicleConfigs.Add(id);
                foreach (var kv in dto.Parts)
                    world.VehiclePartsByConfig[kv.Key] = kv.Value.Select(p => (p.Type, p.PartId)).ToList();
                foreach (var kv in dto.Suits)
                    world.VehicleSuitByConfig[kv.Key] = kv.Value;
            }
            Console.WriteLine($"[TUNING] loaded saved tuning pid={pid} vehicles={dto.Unlocked.Count} parts={dto.Parts.Count}");
        }
        catch (Exception ex)
        {
            Console.WriteLine($"[TUNING] load failed pid={pid}: {ex.Message}");
        }
    }

    private sealed class TuningDto
    {
        public List<uint> Unlocked { get; set; } = [];
        public Dictionary<uint, List<PartDto>> Parts { get; set; } = [];
        public Dictionary<uint, uint> Suits { get; set; } = [];
    }

    private sealed class PartDto
    {
        public uint Type { get; set; }
        public uint PartId { get; set; }
    }
}