using System;
using System.Collections.Generic;
using System.Threading;
using System.Threading.Tasks;
using FinlyticCore.Models.Settings;
using FinlyticCore.Services;
using Microsoft.Playwright;

namespace FinlyticCore.Services.PlaywrightScrapper;

public interface IPlaywrightBrowserFactory : IAsyncDisposable, IDisposable
{
    /// <summary>
    /// Stellt sicher, dass die IBrowser-Instanz verbunden ist.
    /// </summary>
    Task<IBrowser> GetBrowserAsync(CancellationToken cancellationToken = default);

    /// <summary>
    /// Erstellt einen isolierten, vorkonfigurierten Browser-Kontext.
    /// </summary>
    Task<IBrowserContext> CreateContextAsync(BrowserNewContextOptions? options = null, CancellationToken cancellationToken = default);
}

public class PlaywrightBrowserFactory : IPlaywrightBrowserFactory
{
    private readonly IFinlyticLogger<PlaywrightBrowserFactory> _finlyticLogger;
    private readonly SemaphoreSlim _browserLock = new(1, 1);

    private IPlaywright? _playwright;
    private IBrowser? _browser;

    public PlaywrightBrowserFactory(IFinlyticLogger<PlaywrightBrowserFactory> finlyticLogger)
    {
        _finlyticLogger = finlyticLogger;
    }

    public async Task<IBrowser> GetBrowserAsync(CancellationToken cancellationToken = default)
    {
        if (_browser != null && _browser.IsConnected) return _browser;

        await _browserLock.WaitAsync(cancellationToken);
        try
        {
            if (_browser != null && _browser.IsConnected) return _browser;

            _playwright ??= await Playwright.CreateAsync();
            _browser = await _playwright.Chromium.LaunchAsync(new BrowserTypeLaunchOptions
            {
                Headless = true,
                Args = new[]
                {
                    "--no-sandbox",
                    "--disable-setuid-sandbox",
                    "--disable-dev-shm-usage",
                    "--disable-gpu"
                }
            });

            await _finlyticLogger.LogInfoAsync(CoreSettingKeys.PlaywrightChannel, "[PlaywrightFactory] Shared Chromium Instance successfully launched.");
            return _browser;
        }
        finally
        {
            _browserLock.Release();
        }
    }

    public async Task<IBrowserContext> CreateContextAsync(BrowserNewContextOptions? options = null, CancellationToken cancellationToken = default)
    {
        var browser = await GetBrowserAsync(cancellationToken);

        options ??= GetDefaultContextOptions();
        return await browser.NewContextAsync(options);
    }

    public static BrowserNewContextOptions GetDefaultContextOptions() => new()
    {
        UserAgent = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.0.0 Safari/537.36",
        ViewportSize = new ViewportSize { Width = 1280, Height = 900 },
        Locale = "en-US",
        ExtraHTTPHeaders = new Dictionary<string, string>
        {
            ["Accept-Language"] = "en-US,en;q=0.9"
        }
    };

    public void Dispose()
    {
        try
        {
            if (_browser != null)
            {
                _browser.CloseAsync().GetAwaiter().GetResult();
                _browser.DisposeAsync().GetAwaiter().GetResult();
            }
        }
        catch
        {
            // Ignore any sync disposal timeouts
        }
        finally
        {
            _playwright?.Dispose();
            _browserLock.Dispose();
            GC.SuppressFinalize(this);
        }
    }

    public async ValueTask DisposeAsync()
    {
        if (_browser != null)
        {
            try
            {
                await _browser.CloseAsync();
                await _browser.DisposeAsync();
            }
            catch
            {
                // Ignore disposal errors
            }
        }

        _playwright?.Dispose();
        _browserLock.Dispose();

        GC.SuppressFinalize(this);
    }
}