using System;
using System.Collections.Generic;
using System.IO;
using System.Text.Json;
using System.Text.Json.Nodes;
using System.Threading.Tasks;
using Gott.Extensions;
using Gott.Services;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.Configuration;

namespace Gott.Endpoints;

public static class ServerSettingsEndpoint
{
    public static void MapServerSettingsEndpoints(this WebApplication app)
    {
        app.MapGet("/api/admin/server-settings", HandleGet);
        app.MapPut("/api/admin/server-settings", HandleUpdate);
    }

    private static async Task HandleGet(HttpContext ctx, ServerSettingsService settings, IConfiguration config)
    {
        if (!ctx.IsAdmin())
        {
            ctx.Response.StatusCode = 403;
            await ctx.Response.WriteAsJsonAsync(new { error = "Admin access required" });
            return;
        }

        // Port aus appsettings (nicht DB) – als erstes Feld
        var port = config.GetValue<int>("Port", 19000);
        var allSettings = new List<object>
        {
            new
            {
                key = "Port",
                type = "int",
                value = (object)port,
                label = "Server-Port (erfordert Neustart)",
                inputType = "number",
            }
        };
        allSettings.AddRange(settings.GetAll());

        await ctx.Response.WriteAsJsonAsync(new { settings = allSettings });
    }

    private static async Task HandleUpdate(HttpContext ctx, ServerSettingsService settings, IConfiguration config)
    {
        if (!ctx.IsAdmin())
        {
            ctx.Response.StatusCode = 403;
            await ctx.Response.WriteAsJsonAsync(new { error = "Admin access required" });
            return;
        }

        var body = await JsonSerializer.DeserializeAsync<JsonElement>(ctx.Request.Body);
        var hint = "";

        // Port separat behandeln – in appsettings.Production.json speichern
        if (body.TryGetProperty("Port", out var portProp) && portProp.TryGetInt32(out var newPort))
        {
            var currentPort = config.GetValue<int>("Port", 19000);
            if (newPort != currentPort && newPort > 0 && newPort <= 65535)
            {
                SavePortToAppSettings(ctx, newPort);
                hint = "Port geändert – Neustart erforderlich!";
            }
        }

        // Alle anderen Settings in DB speichern
        foreach (var def in ServerSettingsService.Definitions)
        {
            if (!body.TryGetProperty(def.Key, out var prop)) continue;

            switch (def.Type)
            {
                case "string":
                    settings.Set(def.Key, prop.GetString() ?? "");
                    break;
                case "int":
                    settings.SetInt(def.Key, prop.TryGetInt32(out var i) ? i : 0);
                    break;
                case "bool":
                    settings.SetBool(def.Key, prop.ValueKind == JsonValueKind.True);
                    break;
            }
        }

        await ctx.Response.WriteAsJsonAsync(new { ok = true, hint = string.IsNullOrEmpty(hint) ? "Einstellungen gespeichert" : hint });
    }

    private static void SavePortToAppSettings(HttpContext ctx, int port)
    {
        // appsettings.Production.json im ContentRootPath (= publish-Verzeichnis)
        var contentRoot = ctx.RequestServices.GetService(typeof(Microsoft.AspNetCore.Hosting.IWebHostEnvironment)) as Microsoft.AspNetCore.Hosting.IWebHostEnvironment;
        var path = Path.Combine(contentRoot?.ContentRootPath ?? AppContext.BaseDirectory, "appsettings.Production.json");

        JsonObject obj;
        if (File.Exists(path))
        {
            try
            {
                var existing = File.ReadAllText(path);
                obj = JsonNode.Parse(existing) as JsonObject ?? new JsonObject();
            }
            catch
            {
                obj = new JsonObject();
            }
        }
        else
        {
            obj = new JsonObject();
        }

        obj["Port"] = port;

        var options = new JsonSerializerOptions { WriteIndented = true };
        File.WriteAllText(path, obj.ToJsonString(options));
    }
}