using System;
using System.Globalization;
using System.Text.Json;
using System.Text.Json.Nodes;
using System.Threading.Tasks;
using Microsoft.Extensions.Caching.Distributed;
using Microsoft.Extensions.Localization;
using Microsoft.Extensions.Logging;
using Sozsoft.Platform.Entities;
using Sozsoft.Platform.Localization;
using Volo.Abp.Caching;
using Volo.Abp.DependencyInjection;
using Volo.Abp.Domain.Repositories;
using Volo.Abp.Guids;
using Volo.Abp.Localization;
using Volo.Abp.Timing;
using Volo.Abp.Users;

namespace Sozsoft.Mcp;

/// <summary>
/// Gelistirme talebinin Timesheets listesini MCP islemlerinden doldurur. Talep
/// <c>get_dev_request</c> / <c>start_dev_request</c> ile acildiginda kullanicinin etkin talebi
/// olur; ardindan yapilan her yazma islemi o talebe bir satir ekler. Satir modelin dikkatine
/// birakilmaz: aciklama dil anahtarindan Turkce uretilir, sure son etkinlikten bu yana olculur.
/// </summary>
public interface IMcpDevRequestTimesheetRecorder
{
    /// <summary>Talebi kullanicinin etkin talebi yapar ve olcumu baslatir.</summary>
    Task BeginAsync(Guid devRequestId);

    /// <summary>
    /// Etkin talebe bir satir yazar; etkin talep yoksa (islem bir talep dongusunun parcasi
    /// degilse) hicbir sey yapmaz.
    /// </summary>
    Task RecordAsync(string descriptionKey, params object[] args);
}

public class McpDevRequestTimesheetRecorder(
    IDistributedCache<McpDevRequestActivityCacheItem> activityCache,
    IRepository<DevRequest, Guid> devRequestRepository,
    IStringLocalizer<PlatformResource> localizer,
    ICurrentUser currentUser,
    IClock clock,
    IGuidGenerator guidGenerator,
    ILogger<McpDevRequestTimesheetRecorder> logger) : IMcpDevRequestTimesheetRecorder, ITransientDependency
{
    /// <summary>Timesheet satirlarinin dili; talep ekrani Turkce kullanilir.</summary>
    private const string TimesheetCulture = "tr";

    /// <summary>Talep ekranindaki tarih kutusunun okudugu bicim.</summary>
    private const string DateFormat = "yyyy-MM-dd";

    /// <summary>
    /// Etkin talebin omru bir calisma oturumunu kapsar; suresi dolan kayit, gunler once acilmis
    /// bir talebe baska bir isin yazilmasini ve sahte uzun sureyi engeller.
    /// </summary>
    private static readonly TimeSpan ActivityLifetime = TimeSpan.FromHours(12);

    public Task BeginAsync(Guid devRequestId) => StampAsync(devRequestId, clock.Now);

    public async Task RecordAsync(string descriptionKey, params object[] args)
    {
        var activity = await activityCache.GetAsync(ActivityKey());
        if (activity is null)
            return;

        var devRequest = await devRequestRepository.FindAsync(activity.RequestId);
        if (devRequest is null)
            return;

        JsonArray timesheets;
        try
        {
            timesheets = string.IsNullOrWhiteSpace(devRequest.Timesheets)
                ? []
                : JsonNode.Parse(devRequest.Timesheets) as JsonArray ?? throw new JsonException();
        }
        catch (JsonException)
        {
            // Yapilan is (deploy, tablo) zaten tamamlandi; bozuk bir timesheet onu geri almamali.
            logger.LogWarning("Timesheets of development request {RequestId} could not be read; entry skipped.", devRequest.Id);
            return;
        }

        string description;
        using (CultureHelper.Use(TimesheetCulture))
        {
            description = localizer[descriptionKey, args];
        }

        var now = clock.Now;
        var minutes = Math.Max(1, (int)Math.Round((now - activity.At).TotalMinutes));

        timesheets.Add(new JsonObject
        {
            ["id"] = guidGenerator.Create().ToString(),
            ["date"] = now.ToString(DateFormat, CultureInfo.InvariantCulture),
            ["userName"] = currentUser.UserName ?? string.Empty,
            ["description"] = description,
            // Ekranin sure kutusu saati ondalik sayi olarak okur.
            ["duration"] = Math.Round(minutes / 60d, 4)
        });

        devRequest.Timesheets = timesheets.ToJsonString();
        await devRequestRepository.UpdateAsync(devRequest, autoSave: true);
        await StampAsync(devRequest.Id, now);
    }

    private string ActivityKey() => currentUser.Id?.ToString() ?? string.Empty;

    private Task StampAsync(Guid devRequestId, DateTime at) =>
        activityCache.SetAsync(ActivityKey(), new McpDevRequestActivityCacheItem { RequestId = devRequestId, At = at },
            new DistributedCacheEntryOptions { AbsoluteExpirationRelativeToNow = ActivityLifetime });
}