/*
 *
 * (c) Copyright Ascensio System Limited 2010-2018
 *
 * This program is freeware. You can redistribute it and/or modify it under the terms of the GNU 
 * General Public License (GPL) version 3 as published by the Free Software Foundation (https://www.gnu.org/copyleft/gpl.html). 
 * In accordance with Section 7(a) of the GNU GPL its Section 15 shall be amended to the effect that 
 * Ascensio System SIA expressly excludes the warranty of non-infringement of any third-party rights.
 *
 * THIS PROGRAM IS DISTRIBUTED WITHOUT ANY WARRANTY; WITHOUT EVEN THE IMPLIED WARRANTY OF MERCHANTABILITY OR
 * FITNESS FOR A PARTICULAR PURPOSE. For more details, see GNU GPL at https://www.gnu.org/copyleft/gpl.html
 *
 * You can contact Ascensio System SIA by email at sales@onlyoffice.com
 *
 * The interactive user interfaces in modified source and object code versions of ONLYOFFICE must display 
 * Appropriate Legal Notices, as required under Section 5 of the GNU GPL version 3.
 *
 * Pursuant to Section 7 § 3(b) of the GNU GPL you must retain the original ONLYOFFICE logo which contains 
 * relevant author attributions when distributing the software. If the display of the logo in its graphic 
 * form is not reasonably feasible for technical reasons, you must include the words "Powered by ONLYOFFICE" 
 * in every copy of the program you distribute. 
 * Pursuant to Section 7 § 3(e) we decline to grant you any rights under trademark law for use of our trademarks.
 *
*/

namespace ASC.Data.Storage;

[Singletone]
public class WebPathSettings
{
    private readonly IEnumerable<Appender> _appenders;

    public WebPathSettings(Configuration.Storage storage)
    {
        var section = storage;
        if (section != null)
        {
            _appenders = section.Appender;
        }
    }

    public string GetRelativePath(HttpContext httpContext, IOptionsMonitor<ILog> options, string absolutePath)
    {
        if (!Uri.IsWellFormedUriString(absolutePath, UriKind.Absolute))
        {
            throw new ArgumentException($"bad path format {absolutePath} is not absolute");
        }

        var appender = _appenders.FirstOrDefault(x => absolutePath.Contains(x.Append) || (absolutePath.Contains(x.AppendSecure) && !string.IsNullOrEmpty(x.AppendSecure)));
        if (appender == null)
        {
            return absolutePath;
        }

        return SecureHelper.IsSecure(httpContext, options) && !string.IsNullOrEmpty(appender.AppendSecure) ?
            absolutePath.Remove(0, appender.AppendSecure.Length) :
            absolutePath.Remove(0, appender.Append.Length);
    }

    public string GetPath(HttpContext httpContext, IOptionsMonitor<ILog> options, string relativePath)
    {
        if (!string.IsNullOrEmpty(relativePath) && relativePath.IndexOf('~') == 0)
        {
            throw new ArgumentException($"bad path format {relativePath} remove '~'", nameof(relativePath));
        }

        var result = relativePath;
        var ext = Path.GetExtension(relativePath).ToLowerInvariant();

        if (_appenders.Any())
        {
            var avaliableAppenders = _appenders.Where(x => x.Extensions != null && x.Extensions.Split('|').Contains(ext) || string.IsNullOrEmpty(ext)).ToList();
            var avaliableAppendersCount = avaliableAppenders.Count;

            Appender appender;
            if (avaliableAppendersCount > 1)
            {
                appender = avaliableAppenders[relativePath.Length % avaliableAppendersCount];
            }
            else if (avaliableAppendersCount == 1)
            {
                appender = avaliableAppenders.First();
            }
            else
            {
                appender = _appenders.First();
            }

            if (appender.Append.IndexOf('~') == 0)
            {
                var query = string.Empty;
                //Rel path
                if (relativePath.IndexOfAny(new[] { '?', '=', '&' }) != -1)
                {
                    //Cut it
                    query = relativePath.Substring(relativePath.IndexOf('?'));
                    relativePath = relativePath.Substring(0, relativePath.IndexOf('?'));
                }
                //if (HostingEnvironment.IsHosted)
                //{
                //    result = VirtualPathUtility.ToAbsolute(string.Format("{0}/{1}{2}", appender.Append.TrimEnd('/'), relativePath.TrimStart('/'), query));
                //}
                //else
                //{
                result = $"{appender.Append.TrimEnd('/').TrimStart('~')}/{relativePath.TrimStart('/')}{query}";
                //}
            }
            else
            {
                //TODO HostingEnvironment.IsHosted
                if (SecureHelper.IsSecure(httpContext, options) && !string.IsNullOrEmpty(appender.AppendSecure))
                {
                    result = $"{appender.AppendSecure.TrimEnd('/')}/{relativePath.TrimStart('/')}";
                }
                else
                {
                    //Append directly
                    result = $"{appender.Append.TrimEnd('/')}/{relativePath.TrimStart('/')}";
                }
            }
        }

        return result;
    }
}

[Scope]
public class WebPath
{
    public IServiceProvider ServiceProvider { get; }
    public IHostEnvironment HostEnvironment { get; }
    private IHttpClientFactory ClientFactory { get; }

    private static readonly IDictionary<string, bool> _existing = new ConcurrentDictionary<string, bool>();
    private readonly WebPathSettings _webPathSettings;
    private readonly SettingsManager _settingsManager;
    private readonly StorageSettingsHelper _storageSettingsHelper;
    private readonly IHttpContextAccessor _httpContextAccessor;
    private readonly CoreBaseSettings _coreBaseSettings;
    private readonly IOptionsMonitor<ILog> _options;

    public WebPath(
        WebPathSettings webPathSettings,
        IServiceProvider serviceProvider,
        SettingsManager settingsManager,
        StorageSettingsHelper storageSettingsHelper,
        IHostEnvironment hostEnvironment,
        CoreBaseSettings coreBaseSettings,
            IOptionsMonitor<ILog> options,
            IHttpClientFactory clientFactory)
    {
        _webPathSettings = webPathSettings;
        ServiceProvider = serviceProvider;
        _settingsManager = settingsManager;
        _storageSettingsHelper = storageSettingsHelper;
        HostEnvironment = hostEnvironment;
        _coreBaseSettings = coreBaseSettings;
        _options = options;
        ClientFactory = clientFactory;
    }

    public WebPath(
        WebPathSettings webPathSettings,
        IServiceProvider serviceProvider,
        StaticUploader staticUploader,
        SettingsManager settingsManager,
        StorageSettingsHelper storageSettingsHelper,
        IHttpContextAccessor httpContextAccessor,
        IHostEnvironment hostEnvironment,
        CoreBaseSettings coreBaseSettings,
            IOptionsMonitor<ILog> options,
            IHttpClientFactory clientFactory)
            : this(webPathSettings, serviceProvider, settingsManager, storageSettingsHelper, hostEnvironment, coreBaseSettings, options, clientFactory)
    {
        _httpContextAccessor = httpContextAccessor;
    }

    public Task<string> GetPathAsync(string relativePath)
    {
        if (!string.IsNullOrEmpty(relativePath) && relativePath.IndexOf('~') == 0)
        {
            throw new ArgumentException($"bad path format {relativePath} remove '~'", nameof(relativePath));
        }

        return InternalGetPathAsync(relativePath);
    }

    private async Task<string> InternalGetPathAsync(string relativePath)
    {
        if (_coreBaseSettings.Standalone && ServiceProvider.GetService<StaticUploader>().CanUpload()) //hack for skip resolve DistributedTaskQueueOptionsManager
        {
            try
            {
                var uri = await _storageSettingsHelper.DataStore(_settingsManager.Load<CdnStorageSettings>()).GetInternalUriAsync("", relativePath, TimeSpan.Zero, null);
                var result = uri.AbsoluteUri.ToLower();
                if (!string.IsNullOrEmpty(result)) return result;
            }
            catch (Exception)
            {

            }
        }

        return _webPathSettings.GetPath(_httpContextAccessor?.HttpContext, _options, relativePath);
    }

    public async Task<bool> ExistsAsync(string relativePath)
    {
        var path = await GetPathAsync(relativePath);
        if (!_existing.ContainsKey(path))
        {
            if (Uri.IsWellFormedUriString(path, UriKind.Relative) && _httpContextAccessor?.HttpContext != null)
            {
                //Local
                _existing[path] = File.Exists(CrossPlatform.PathCombine(HostEnvironment.ContentRootPath, path));
            }
            if (Uri.IsWellFormedUriString(path, UriKind.Absolute))
            {
                //Make request
                _existing[path] = CheckWebPath(path);
            }
        }

        return _existing[path];
    }

    private bool CheckWebPath(string path)
    {
        try
        {
            var request = new HttpRequestMessage();
            request.RequestUri = new Uri(path);
            request.Method = HttpMethod.Head;
            var httpClient = ClientFactory.CreateClient();
            using var response = httpClient.Send(request);

            return response.StatusCode == HttpStatusCode.OK;
        }
        catch (Exception)
        {
            return false;
        }
    }
}