using System;
using System.Collections.Generic;
using System.Threading;
using System.Threading.Tasks;
using GmRelay.Bot.Features.Sessions.CreateSession.Wizard;
using GmRelay.Shared.Features.Sessions.CreateSession.Wizard;
using Microsoft.Extensions.Logging.Abstractions;
using Telegram.Bot.Types;
using Telegram.Bot.Types.ReplyMarkups;
using WizardBot = GmRelay.Bot.Features.Sessions.CreateSession.Wizard.GameCreationWizard;
using WizardMessenger = GmRelay.Bot.Features.Sessions.CreateSession.Wizard.ITelegramWizardMessenger;

namespace GmRelay.Bot.Tests.Features.Sessions.CreateSession.Wizard;

/// <summary>
/// Hand-rolled test doubles and helpers for wizard unit tests. The project
/// convention is to use fakes (not a mocking framework) so the suite stays
/// AOT-friendly and the production code doesn't grow virtual members just
/// for tests.
/// </summary>
internal static class WizardTestFakes
{
    public static WizardBot BuildWizard(out FakeWizardDraftRepository drafts, out FakeWizardMessenger messenger)
    {
        drafts = new FakeWizardDraftRepository();
        messenger = new FakeWizardMessenger();
        return new WizardBot(drafts, messenger, NullLogger<WizardBot>.Instance);
    }

    public static WizardDraft NewDraft(string step, WizardPayload? payload = null, long ownerId = 100) => new()
    {
        Id = Guid.NewGuid(),
        ChatId = 42,
        MessageThreadId = null,
        OwnerTelegramId = ownerId,
        Step = step,
        DraftMessageId = 7,
        PayloadJson = System.Text.Json.JsonSerializer.Serialize(
            payload ?? new WizardPayload(),
            WizardPayloadJsonContext.Default.WizardPayload),
        CreatedAt = DateTimeOffset.UtcNow,
        UpdatedAt = DateTimeOffset.UtcNow,
        ExpiresAt = DateTimeOffset.UtcNow.AddHours(24),
    };

    public static Update CallbackUpdate(string data, long ownerId = 100) => new()
    {
        CallbackQuery = new CallbackQuery
        {
            Id = "cb-1",
            Data = data,
            From = new User { Id = ownerId, FirstName = "GM" },
            Message = new Message
            {
                Chat = new Chat { Id = 42 },
            },
        },
    };

    public static Update TextUpdate(string text, long ownerId = 100) => new()
    {
        Message = new Message
        {
            Text = text,
            Chat = new Chat { Id = 42 },
            From = new User { Id = ownerId, FirstName = "GM" },
        },
    };
}

/// <summary>
/// Records every call the wizard makes against the draft repository. Backed by
/// an in-memory dictionary so tests can pre-seed an "active" draft for the
/// wizard to mutate.
/// </summary>
internal sealed class FakeWizardDraftRepository : IWizardDraftRepository
{
    private readonly Dictionary<Guid, WizardDraft> store = new();

    public List<Guid> DeletedIds { get; } = new();

    public List<WizardDraft> Upserts { get; } = new();

    public int ExpiredDeleted { get; set; }

    public void Seed(WizardDraft draft) => store[draft.Id] = draft;

    public Task<WizardDraft?> GetActiveAsync(long chatId, int? messageThreadId, long ownerTelegramId, CancellationToken ct)
    {
        foreach (var d in store.Values)
        {
            if (d.ChatId == chatId &&
                d.MessageThreadId == messageThreadId &&
                d.OwnerTelegramId == ownerTelegramId &&
                d.ExpiresAt > DateTimeOffset.UtcNow)
            {
                return Task.FromResult<WizardDraft?>(d);
            }
        }
        return Task.FromResult<WizardDraft?>(null);
    }

    public Task UpsertAsync(WizardDraft draft, CancellationToken ct)
    {
        // Clone so tests can compare state without aliasing.
        Upserts.Add(new WizardDraft
        {
            Id = draft.Id,
            ChatId = draft.ChatId,
            MessageThreadId = draft.MessageThreadId,
            OwnerTelegramId = draft.OwnerTelegramId,
            Step = draft.Step,
            PayloadJson = draft.PayloadJson,
            DraftMessageId = draft.DraftMessageId,
            CreatedAt = draft.CreatedAt,
            UpdatedAt = draft.UpdatedAt,
            ExpiresAt = draft.ExpiresAt,
        });
        store[draft.Id] = draft;
        return Task.CompletedTask;
    }

    public Task DeleteAsync(Guid id, CancellationToken ct)
    {
        DeletedIds.Add(id);
        store.Remove(id);
        return Task.CompletedTask;
    }

    public Task<int> DeleteExpiredAsync(CancellationToken ct)
    {
        var count = ExpiredDeleted;
        ExpiredDeleted = 0;
        return Task.FromResult(count);
    }
}

/// <summary>
/// Records every call the wizard makes against the messenger. Default return
/// values (empty clubs, message-id 1) match what the wizard expects to see
/// in steady state.
/// </summary>
internal sealed class FakeWizardMessenger : ITelegramWizardMessenger
{
    public List<(long ChatId, int? ThreadId, long MsgId, string Text)> Edits { get; } = new();

    public List<string> AnsweredCallbacks { get; } = new();

    public List<(long ChatId, int? ThreadId, string Text)> Sends { get; } = new();

    public IReadOnlyList<WizardClubOption> Clubs { get; set; } = Array.Empty<WizardClubOption>();

    public Task<long> EditMessageTextAsync(
        long chatId,
        int? messageThreadId,
        long messageId,
        string text,
        InlineKeyboardMarkup keyboard,
        CancellationToken ct)
    {
        Edits.Add((chatId, messageThreadId, messageId, text));
        return Task.FromResult(messageId);
    }

    public Task<long> SendGroupMessageAsync(
        long chatId,
        int? messageThreadId,
        string text,
        InlineKeyboardMarkup keyboard,
        CancellationToken ct)
    {
        Sends.Add((chatId, messageThreadId, text));
        return Task.FromResult(99L);
    }

    public Task AnswerCallbackAsync(string callbackId, string? text, CancellationToken ct)
    {
        AnsweredCallbacks.Add(callbackId);
        return Task.CompletedTask;
    }

    public Task<IReadOnlyList<WizardClubOption>> GetGmClubsAsync(long ownerTelegramId, CancellationToken ct)
        => Task.FromResult(Clubs);
}