Add HsnTsnClient and related classes for vehicle data scraping

- Implement HsnTsnClient to fetch vehicle data from hsn-tsn.de - Create VehicleDetail and HsnTsnVehicle classes for data representation - Add CSV output functionality in Program.cs - Include necessary NuGet packages in project file - Add README with usage instructions
2026-03-04 14:36:40 +03:00
commit fb2c2cdb8a
6 changed files with 617 additions and 0 deletions
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+bin/
+obj/
+.idea/
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+# hsntsn-scraper
+
+.NET console scraper.
+
+Kaynak: `http://www.hsn-tsn.de/`
+
+CSV cikti alanlari:
+
+- `HsnTsn`, `Hsn`, `Tsn`
+- `Brand`, `VehicleType`, `Model`, `OfficialType`
+- `YearFrom`, `YearTo`
+- `PowerPs`, `PowerKw`, `DisplacementCcm`, `FuelType`
+- `MatchKey`
+- `SourceQuery`, `SourceListUrl`, `SourceDetailUrl`
+
+## Calistirma
+
+Tum marka sayfalarini tara:
+
+```bash
+dotnet run --project src/HsnTsnScraper/HsnTsnScraper.csproj > hsntsn.csv
+```
+
+Sadece verilen sorgulari tara (`stdin`):
+
+```bash
+printf "0588\nGolf\n" | dotnet run --project src/HsnTsnScraper/HsnTsnScraper.csproj > hsntsn.csv
+```
+
+Detay sayfasi zenginlestirmesini kapat:
+
+```bash
+printf "0588\n" | dotnet run --project src/HsnTsnScraper/HsnTsnScraper.csproj -- --skip-details
+```
@@ -0,0 +1,39 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 17
+VisualStudioVersion = 17.0.31903.59
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "src", "src", "{827E0CD3-B72D-47B6-A68D-7590B98EB39B}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "HsnTsnScraper", "src\HsnTsnScraper\HsnTsnScraper.csproj", "{F5352DDD-D3DE-4550-A50B-B28C00AA6785}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Debug|x64 = Debug|x64
+		Debug|x86 = Debug|x86
+		Release|Any CPU = Release|Any CPU
+		Release|x64 = Release|x64
+		Release|x86 = Release|x86
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{F5352DDD-D3DE-4550-A50B-B28C00AA6785}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{F5352DDD-D3DE-4550-A50B-B28C00AA6785}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{F5352DDD-D3DE-4550-A50B-B28C00AA6785}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{F5352DDD-D3DE-4550-A50B-B28C00AA6785}.Debug|x64.Build.0 = Debug|Any CPU
+		{F5352DDD-D3DE-4550-A50B-B28C00AA6785}.Debug|x86.ActiveCfg = Debug|Any CPU
+		{F5352DDD-D3DE-4550-A50B-B28C00AA6785}.Debug|x86.Build.0 = Debug|Any CPU
+		{F5352DDD-D3DE-4550-A50B-B28C00AA6785}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{F5352DDD-D3DE-4550-A50B-B28C00AA6785}.Release|Any CPU.Build.0 = Release|Any CPU
+		{F5352DDD-D3DE-4550-A50B-B28C00AA6785}.Release|x64.ActiveCfg = Release|Any CPU
+		{F5352DDD-D3DE-4550-A50B-B28C00AA6785}.Release|x64.Build.0 = Release|Any CPU
+		{F5352DDD-D3DE-4550-A50B-B28C00AA6785}.Release|x86.ActiveCfg = Release|Any CPU
+		{F5352DDD-D3DE-4550-A50B-B28C00AA6785}.Release|x86.Build.0 = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(NestedProjects) = preSolution
+		{F5352DDD-D3DE-4550-A50B-B28C00AA6785} = {827E0CD3-B72D-47B6-A68D-7590B98EB39B}
+	EndGlobalSection
+EndGlobal
@@ -0,0 +1,361 @@
+using System.Net;
+using System.Text.RegularExpressions;
+using HtmlAgilityPack;
+using Microsoft.Extensions.Http;
+using Polly;
+using Polly.Extensions.Http;
+
+namespace HsnTsnScraper;
+
+public sealed class HsnTsnClient : IDisposable
+{
+    private static readonly Regex HsnTsnRegex = new(@"(?<hsn>\d{4})\s*/\s*(?<tsn>[A-Z0-9]{3})", RegexOptions.Compiled);
+    private static readonly Regex PsKwRegex = new(@"(?<ps>\d+)\s*PS\s*\((?<kw>\d+)\s*kW\)", RegexOptions.Compiled | RegexOptions.IgnoreCase);
+    private static readonly Regex CcmRegex = new(@"(?<ccm>[\d\.\,]+)\s*ccm", RegexOptions.Compiled | RegexOptions.IgnoreCase);
+    private static readonly Regex YearRangeRegex = new(@"(?<from>\d{4})(?:\D+(?<to>\d{4}))?", RegexOptions.Compiled);
+    private static readonly HashSet<string> ExcludedLinks = new(StringComparer.OrdinalIgnoreCase)
+    {
+        "/impressum.php",
+        "/datenschutz.php",
+        "/datenschutz"
+    };
+
+    private readonly HttpClient _client;
+
+    public HsnTsnClient(string baseUrl = "http://www.hsn-tsn.de/")
+    {
+        var retryPolicy = HttpPolicyExtensions
+            .HandleTransientHttpError()
+            .OrResult(x => x.StatusCode == HttpStatusCode.TooManyRequests)
+            .WaitAndRetryAsync(3, retryAttempt => TimeSpan.FromSeconds(Math.Pow(2, retryAttempt)));
+
+        var socketHandler = new SocketsHttpHandler
+        {
+            PooledConnectionLifetime = TimeSpan.FromMinutes(5),
+            UseCookies = false
+        };
+
+        var pollyHandler = new PolicyHttpMessageHandler(retryPolicy)
+        {
+            InnerHandler = socketHandler
+        };
+
+        _client = new HttpClient(pollyHandler)
+        {
+            BaseAddress = new Uri(baseUrl)
+        };
+
+        _client.DefaultRequestHeaders.UserAgent.ParseAdd("Mozilla/5.0 (compatible; hsntsn-scraper/1.0)");
+    }
+
+    public async Task<IReadOnlyList<string>> GetBrandPageUrls(CancellationToken cancellationToken = default)
+    {
+        var homeHtml = await GetStringAsync("/", cancellationToken);
+        var doc = LoadDocument(homeHtml);
+        var links = doc.DocumentNode.SelectNodes("//a[@href]") ?? new HtmlNodeCollection(null);
+
+        var result = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
+        foreach (var link in links)
+        {
+            var href = link.GetAttributeValue("href", string.Empty).Trim();
+            if (string.IsNullOrWhiteSpace(href))
+            {
+                continue;
+            }
+
+            if (!href.EndsWith(".html", StringComparison.OrdinalIgnoreCase))
+            {
+                continue;
+            }
+
+            if (ExcludedLinks.Contains(href))
+            {
+                continue;
+            }
+
+            if (href.StartsWith("http://", StringComparison.OrdinalIgnoreCase) ||
+                href.StartsWith("https://", StringComparison.OrdinalIgnoreCase))
+            {
+                result.Add(href);
+            }
+            else
+            {
+                result.Add(new Uri(_client.BaseAddress!, href).ToString());
+            }
+        }
+
+        return result.OrderBy(x => x, StringComparer.OrdinalIgnoreCase).ToArray();
+    }
+
+    public async Task<IReadOnlyList<HsnTsnVehicle>> GetVehiclesFromSearchAsync(string query, CancellationToken cancellationToken = default)
+    {
+        var encoded = Uri.EscapeDataString(query);
+        var url = $"/liste.php?string={encoded}";
+        var html = await GetStringAsync(url, cancellationToken);
+        return ParseVehiclesFromListPage(html, new Uri(_client.BaseAddress!, url).ToString(), query);
+    }
+
+    public async Task<IReadOnlyList<HsnTsnVehicle>> GetVehiclesFromBrandPageAsync(string absoluteUrl, CancellationToken cancellationToken = default)
+    {
+        var html = await GetStringAsync(absoluteUrl, cancellationToken);
+        return ParseVehiclesFromListPage(html, absoluteUrl, null);
+    }
+
+    public async Task<VehicleDetail?> GetVehicleDetailAsync(string detailUrl, CancellationToken cancellationToken = default)
+    {
+        if (string.IsNullOrWhiteSpace(detailUrl))
+        {
+            return null;
+        }
+
+        var html = await GetStringAsync(detailUrl, cancellationToken);
+        var doc = LoadDocument(html);
+
+        var carNode = doc.DocumentNode.SelectSingleNode("//div[@id='car']");
+        if (carNode is null)
+        {
+            return null;
+        }
+
+        var detail = new VehicleDetail
+        {
+            Hsn = carNode.GetAttributeValue("data-hsn", string.Empty).Trim(),
+            Tsn = carNode.GetAttributeValue("data-tsn", string.Empty).Trim(),
+            Brand = HtmlEntity.DeEntitize(doc.DocumentNode.SelectSingleNode("//span[@property='brand']//span[@property='name']")?.InnerText ?? string.Empty).Trim(),
+            Model = HtmlEntity.DeEntitize(doc.DocumentNode.SelectSingleNode("//span[@property='model']")?.InnerText ?? string.Empty).Trim(),
+            OfficialType = HtmlEntity.DeEntitize(doc.DocumentNode.SelectSingleNode("//span[@property='alternateName']")?.InnerText ?? string.Empty).Trim(),
+            CanonicalUrl = doc.DocumentNode.SelectSingleNode("//meta[@property='url']")?.GetAttributeValue("content", string.Empty).Trim() ?? string.Empty
+        };
+
+        var yearText = HtmlEntity.DeEntitize(doc.DocumentNode.SelectSingleNode("//small[@property='vehicleModelDate']")?.InnerText ?? string.Empty).Trim();
+        ParseYearRange(yearText, out var fromYear, out var toYear);
+        detail.YearFrom = fromYear;
+        detail.YearTo = toYear;
+
+        return detail;
+    }
+
+    public void Dispose()
+    {
+        _client.Dispose();
+    }
+
+    private async Task<string> GetStringAsync(string relativeOrAbsoluteUrl, CancellationToken cancellationToken)
+    {
+        using var response = await _client.GetAsync(relativeOrAbsoluteUrl, cancellationToken);
+        response.EnsureSuccessStatusCode();
+        return await response.Content.ReadAsStringAsync(cancellationToken);
+    }
+
+    private IReadOnlyList<HsnTsnVehicle> ParseVehiclesFromListPage(string html, string sourceListUrl, string? sourceQuery)
+    {
+        var doc = LoadDocument(html);
+        var rows = doc.DocumentNode.SelectNodes("//table//tr") ?? new HtmlNodeCollection(null);
+        var pageHeading = Clean(doc.DocumentNode.SelectSingleNode("//h1")?.InnerText ?? string.Empty);
+        var pageBrand = IsLikelyBrandHeading(pageHeading) ? pageHeading : string.Empty;
+        var result = new List<HsnTsnVehicle>();
+
+        foreach (var row in rows)
+        {
+            var cells = row.SelectNodes("./td");
+            if (cells is null || cells.Count < 5)
+            {
+                continue;
+            }
+
+            var hsnTsnText = Clean(cells[0].InnerText);
+            var match = HsnTsnRegex.Match(hsnTsnText);
+            if (!match.Success)
+            {
+                continue;
+            }
+
+            var vehicleTypeRaw = Clean(cells[1].InnerText);
+            var detailHref = cells[1].SelectSingleNode(".//a[@href]")?.GetAttributeValue("href", string.Empty) ?? string.Empty;
+            var detailUrl = ToAbsoluteUrl(detailHref);
+
+            var powerText = Clean(cells[2].InnerText);
+            ParsePower(powerText, out var ps, out var kw);
+
+            var displacementText = Clean(cells[3].InnerText);
+            var displacementCcm = ParseDisplacement(displacementText);
+
+            var fuelType = Clean(cells[4].InnerText);
+            var brand = !string.IsNullOrWhiteSpace(pageBrand) ? pageBrand : ExtractBrand(vehicleTypeRaw);
+
+            var vehicle = new HsnTsnVehicle
+            {
+                Hsn = match.Groups["hsn"].Value,
+                Tsn = match.Groups["tsn"].Value,
+                HsnTsn = $"{match.Groups["hsn"].Value}/{match.Groups["tsn"].Value}",
+                Brand = brand,
+                VehicleType = vehicleTypeRaw,
+                PowerPs = ps,
+                PowerKw = kw,
+                DisplacementCcm = displacementCcm,
+                FuelType = fuelType,
+                SourceListUrl = sourceListUrl,
+                SourceDetailUrl = detailUrl,
+                SourceQuery = sourceQuery ?? string.Empty
+            };
+
+            vehicle.MatchKey = BuildMatchKey(vehicle);
+            result.Add(vehicle);
+        }
+
+        return result;
+    }
+
+    private string ToAbsoluteUrl(string href)
+    {
+        if (string.IsNullOrWhiteSpace(href))
+        {
+            return string.Empty;
+        }
+
+        if (Uri.TryCreate(href, UriKind.Absolute, out var absolute) &&
+            (absolute.Scheme.Equals(Uri.UriSchemeHttp, StringComparison.OrdinalIgnoreCase) ||
+             absolute.Scheme.Equals(Uri.UriSchemeHttps, StringComparison.OrdinalIgnoreCase)))
+        {
+            return absolute.ToString();
+        }
+
+        var normalized = href.StartsWith("/", StringComparison.Ordinal) ? href : $"/{href.TrimStart('/')}";
+        return new Uri(_client.BaseAddress!, normalized).ToString();
+    }
+
+    private static HtmlDocument LoadDocument(string html)
+    {
+        var doc = new HtmlDocument();
+        doc.LoadHtml(html);
+        return doc;
+    }
+
+    private static string Clean(string value)
+    {
+        return HtmlEntity.DeEntitize(value).Replace('\u00A0', ' ').Trim();
+    }
+
+    private static void ParsePower(string powerText, out int? ps, out int? kw)
+    {
+        ps = null;
+        kw = null;
+
+        var match = PsKwRegex.Match(powerText);
+        if (!match.Success)
+        {
+            return;
+        }
+
+        if (int.TryParse(match.Groups["ps"].Value, out var psParsed))
+        {
+            ps = psParsed;
+        }
+
+        if (int.TryParse(match.Groups["kw"].Value, out var kwParsed))
+        {
+            kw = kwParsed;
+        }
+    }
+
+    private static int? ParseDisplacement(string text)
+    {
+        var match = CcmRegex.Match(text);
+        if (!match.Success)
+        {
+            return null;
+        }
+
+        var numeric = match.Groups["ccm"].Value.Replace(".", string.Empty).Replace(",", string.Empty);
+        return int.TryParse(numeric, out var ccm) ? ccm : null;
+    }
+
+    private static void ParseYearRange(string yearText, out int? fromYear, out int? toYear)
+    {
+        fromYear = null;
+        toYear = null;
+
+        var match = YearRangeRegex.Match(yearText);
+        if (!match.Success)
+        {
+            return;
+        }
+
+        if (int.TryParse(match.Groups["from"].Value, out var from))
+        {
+            fromYear = from;
+        }
+
+        if (int.TryParse(match.Groups["to"].Value, out var to))
+        {
+            toYear = to;
+        }
+    }
+
+    private static string ExtractBrand(string vehicleType)
+    {
+        if (string.IsNullOrWhiteSpace(vehicleType))
+        {
+            return string.Empty;
+        }
+
+        var parts = vehicleType.Split(' ', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries);
+        return parts.Length == 0 ? string.Empty : parts[0];
+    }
+
+    private static bool IsLikelyBrandHeading(string heading)
+    {
+        if (string.IsNullOrWhiteSpace(heading))
+        {
+            return false;
+        }
+
+        return !Regex.IsMatch(heading, @"^\d{4}$");
+    }
+
+    private static string BuildMatchKey(HsnTsnVehicle vehicle)
+    {
+        var raw = $"{vehicle.Brand} {vehicle.VehicleType} {vehicle.OfficialType} {vehicle.PowerKw} {vehicle.FuelType}".Trim();
+        var normalized = raw.ToUpperInvariant()
+            .Replace("Ä", "AE")
+            .Replace("Ö", "OE")
+            .Replace("Ü", "UE")
+            .Replace("ß", "SS");
+
+        var cleaned = Regex.Replace(normalized, @"[^A-Z0-9]+", " ").Trim();
+        return Regex.Replace(cleaned, @"\s+", " ");
+    }
+}
+
+public sealed class VehicleDetail
+{
+    public string Hsn { get; set; } = string.Empty;
+    public string Tsn { get; set; } = string.Empty;
+    public string Brand { get; set; } = string.Empty;
+    public string Model { get; set; } = string.Empty;
+    public string OfficialType { get; set; } = string.Empty;
+    public int? YearFrom { get; set; }
+    public int? YearTo { get; set; }
+    public string CanonicalUrl { get; set; } = string.Empty;
+}
+
+public sealed class HsnTsnVehicle
+{
+    public string HsnTsn { get; set; } = string.Empty;
+    public string Hsn { get; set; } = string.Empty;
+    public string Tsn { get; set; } = string.Empty;
+    public string Brand { get; set; } = string.Empty;
+    public string VehicleType { get; set; } = string.Empty;
+    public string Model { get; set; } = string.Empty;
+    public string OfficialType { get; set; } = string.Empty;
+    public int? YearFrom { get; set; }
+    public int? YearTo { get; set; }
+    public int? PowerPs { get; set; }
+    public int? PowerKw { get; set; }
+    public int? DisplacementCcm { get; set; }
+    public string FuelType { get; set; } = string.Empty;
+    public string MatchKey { get; set; } = string.Empty;
+    public string SourceQuery { get; set; } = string.Empty;
+    public string SourceListUrl { get; set; } = string.Empty;
+    public string SourceDetailUrl { get; set; } = string.Empty;
+}
@@ -0,0 +1,17 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net9.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="CsvHelper" Version="33.0.1" />
+    <PackageReference Include="HtmlAgilityPack" Version="1.11.71" />
+    <PackageReference Include="Microsoft.Extensions.Http" Version="8.0.1" />
+    <PackageReference Include="Microsoft.Extensions.Http.Polly" Version="8.0.10" />
+  </ItemGroup>
+
+</Project>
@@ -0,0 +1,163 @@
+using System.Globalization;
+using CsvHelper;
+using CsvHelper.Configuration;
+using HsnTsnScraper;
+
+var includeDetails = !args.Contains("--skip-details", StringComparer.OrdinalIgnoreCase);
+
+using var client = new HsnTsnClient();
+var map = new Dictionary<string, HsnTsnVehicle>(StringComparer.OrdinalIgnoreCase);
+
+if (Console.IsInputRedirected)
+{
+    await foreach (var query in ReadInput())
+    {
+        var vehicles = await client.GetVehiclesFromSearchAsync(query);
+        Merge(map, vehicles);
+    }
+}
+else
+{
+    var brandUrls = await client.GetBrandPageUrls();
+    foreach (var url in brandUrls)
+    {
+        var vehicles = await client.GetVehiclesFromBrandPageAsync(url);
+        Merge(map, vehicles);
+    }
+}
+
+if (includeDetails)
+{
+    foreach (var vehicle in map.Values)
+    {
+        var detail = await client.GetVehicleDetailAsync(vehicle.SourceDetailUrl);
+        if (detail is null)
+        {
+            continue;
+        }
+
+        if (!string.IsNullOrWhiteSpace(detail.Brand))
+        {
+            vehicle.Brand = detail.Brand;
+        }
+
+        vehicle.Model = detail.Model;
+        vehicle.OfficialType = detail.OfficialType;
+        vehicle.YearFrom = detail.YearFrom;
+        vehicle.YearTo = detail.YearTo;
+
+        if (!string.IsNullOrWhiteSpace(detail.CanonicalUrl))
+        {
+            vehicle.SourceDetailUrl = detail.CanonicalUrl;
+        }
+    }
+}
+
+foreach (var vehicle in map.Values)
+{
+    vehicle.MatchKey = BuildMatchKey(vehicle);
+}
+
+await using var csvWriter = new CsvWriter(Console.Out, new CsvConfiguration(CultureInfo.InvariantCulture)
+{
+    Delimiter = ";"
+});
+
+csvWriter.WriteHeader<HsnTsnVehicle>();
+await csvWriter.NextRecordAsync();
+
+foreach (var vehicle in map.Values.OrderBy(x => x.Hsn, StringComparer.OrdinalIgnoreCase).ThenBy(x => x.Tsn, StringComparer.OrdinalIgnoreCase))
+{
+    csvWriter.WriteRecord(vehicle);
+    await csvWriter.NextRecordAsync();
+}
+
+await csvWriter.FlushAsync();
+
+return;
+
+void Merge(IDictionary<string, HsnTsnVehicle> mapByHsnTsn, IEnumerable<HsnTsnVehicle> vehicles)
+{
+    foreach (var vehicle in vehicles)
+    {
+        var key = vehicle.HsnTsn;
+        if (!mapByHsnTsn.TryGetValue(key, out var existing))
+        {
+            mapByHsnTsn[key] = vehicle;
+            continue;
+        }
+
+        if (string.IsNullOrWhiteSpace(existing.VehicleType) && !string.IsNullOrWhiteSpace(vehicle.VehicleType))
+        {
+            existing.VehicleType = vehicle.VehicleType;
+        }
+
+        if (existing.PowerPs is null && vehicle.PowerPs is not null)
+        {
+            existing.PowerPs = vehicle.PowerPs;
+        }
+
+        if (existing.PowerKw is null && vehicle.PowerKw is not null)
+        {
+            existing.PowerKw = vehicle.PowerKw;
+        }
+
+        if (existing.DisplacementCcm is null && vehicle.DisplacementCcm is not null)
+        {
+            existing.DisplacementCcm = vehicle.DisplacementCcm;
+        }
+
+        if (string.IsNullOrWhiteSpace(existing.FuelType) && !string.IsNullOrWhiteSpace(vehicle.FuelType))
+        {
+            existing.FuelType = vehicle.FuelType;
+        }
+
+        if (string.IsNullOrWhiteSpace(existing.SourceQuery) && !string.IsNullOrWhiteSpace(vehicle.SourceQuery))
+        {
+            existing.SourceQuery = vehicle.SourceQuery;
+        }
+
+        if (string.IsNullOrWhiteSpace(existing.SourceListUrl) && !string.IsNullOrWhiteSpace(vehicle.SourceListUrl))
+        {
+            existing.SourceListUrl = vehicle.SourceListUrl;
+        }
+
+        if (string.IsNullOrWhiteSpace(existing.SourceDetailUrl) && !string.IsNullOrWhiteSpace(vehicle.SourceDetailUrl))
+        {
+            existing.SourceDetailUrl = vehicle.SourceDetailUrl;
+        }
+    }
+}
+
+async IAsyncEnumerable<string> ReadInput()
+{
+    var seen = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
+    while (await Console.In.ReadLineAsync() is { } line)
+    {
+        var value = line.Trim();
+        if (string.IsNullOrWhiteSpace(value))
+        {
+            continue;
+        }
+
+        if (!seen.Add(value))
+        {
+            continue;
+        }
+
+        yield return value;
+    }
+}
+
+string BuildMatchKey(HsnTsnVehicle vehicle)
+{
+    var raw = $"{vehicle.Brand} {vehicle.VehicleType} {vehicle.Model} {vehicle.OfficialType} {vehicle.PowerKw} {vehicle.DisplacementCcm} {vehicle.FuelType}";
+    var normalized = raw.ToUpperInvariant()
+        .Replace("Ä", "AE")
+        .Replace("Ö", "OE")
+        .Replace("Ü", "UE")
+        .Replace("ß", "SS");
+
+    normalized = System.Text.RegularExpressions.Regex.Replace(normalized, @"[^A-Z0-9]+", " ").Trim();
+    return System.Text.RegularExpressions.Regex.Replace(normalized, @"\s+", " ");
+}