Sales Price Page Dropdown Codes

using System.Net.Http.Headers;
using System.Text;
using System.Text.Json;

// ---- EDIT THESE -----------------------------------------------------------
const string BaseUrl = "https://play.p21server.com";   // your P21 server
const string Username = "apiuser";
const string Password = "your-password";
const string CompanyId = "ACME";
const string ProductGroupId = "HVAC";
const string SupplierId = "10050";
const string Description = "P2-L5-10050-HVAC-WHOLESALE";
const string EffectiveDate = "2025-01-01";
const string ExpirationDate = "2030-12-31";
const string Multiplier = "0.85";          // calculation_value1 -- tier 1, qty 1+
// ---------------------------------------------------------------------------

var handler = new HttpClientHandler
{
    // Test tenants often present a self-signed cert. Delete this line in production.
    ServerCertificateCustomValidationCallback =
        HttpClientHandler.DangerousAcceptAnyServerCertificateValidator,
};
using var client = new HttpClient(handler) { Timeout = TimeSpan.FromMinutes(2) };
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));

var token = await GetTokenAsync(client);
var uiServer = await GetUiServerAsync(client, token);
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);

// A session must exist before any window can be opened.
var sessionResponse = await client.PostAsync(
    $"{uiServer}/api/ui/interactive/sessions",
    Json(new { ResponseWindowHandlingEnabled = false }));
sessionResponse.EnsureSuccessStatusCode();

// ServiceName is the only reliable window identifier -- Name/Title can 400.
var openResponse = await client.PostAsync(
    $"{uiServer}/api/ui/interactive/v2/window",
    Json(new { ServiceName = "SalesPricePage" }));
openResponse.EnsureSuccessStatusCode();

using var opened = JsonDocument.Parse(await openResponse.Content.ReadAsStringAsync());
var windowId = opened.RootElement.GetProperty("WindowId").GetString()!;
Console.WriteLine($"Window opened: {windowId}");

// One field per call -- a batched /v2/change is non-atomic on 2026.1.
async Task ChangeAsync(string tab, string datawindow, string field, string value)
{
    var response = await client.PutAsync(
        $"{uiServer}/api/ui/interactive/v2/change",
        Json(new
        {
            WindowId = windowId,
            List = new[]
            {
                new
                {
                    TabName = tab,
                    DatawindowName = datawindow,     // required since 25.2
                    FieldName = field,
                    Value = value,
                }
            }
        }));
    response.EnsureSuccessStatusCode();
}

try
{
    // Step 1: page type FIRST -- it determines which fields are available
    await ChangeAsync("FORM", "form", "price_page_type_cd", "Supplier / Product Group");

    // Step 2: company_id BEFORE product_group_id
    await ChangeAsync("FORM", "form", "company_id", CompanyId);

    // Step 3: product group
    await ChangeAsync("FORM", "form", "product_group_id", ProductGroupId);

    // Step 4: supplier
    await ChangeAsync("FORM", "form", "supplier_id", SupplierId);

    // Step 5: description
    await ChangeAsync("FORM", "form", "description", Description);

    // Steps 6-7: pricing method and source price
    await ChangeAsync("FORM", "form", "pricing_method_cd", "Source");
    await ChangeAsync("FORM", "form", "source_price_cd", "Supplier List Price");

    // Step 8: dates
    await ChangeAsync("FORM", "form", "effective_date", EffectiveDate);
    await ChangeAsync("FORM", "form", "expiration_date", ExpirationDate);

    // Step 9: switch to the VALUES tab (2026.1 binds PageName, not TabName)
    var tabResponse = await client.PutAsync(
        $"{uiServer}/api/ui/interactive/v2/tab",
        Json(new { WindowId = windowId, PageName = "VALUES" }));
    tabResponse.EnsureSuccessStatusCode();

    // Steps 10-11: calculation method, then the tier-1 value
    await ChangeAsync("VALUES", "values", "calculation_method_cd", "Multiplier");
    await ChangeAsync("VALUES", "values", "calculation_value1", Multiplier);

    // Save -- v2 takes the bare WindowId string as the JSON body
    var saveResponse = await client.PutAsync(
        $"{uiServer}/api/ui/interactive/v2/data", Json(windowId));
    saveResponse.EnsureSuccessStatusCode();

    using var result = JsonDocument.Parse(await saveResponse.Content.ReadAsStringAsync());
    // ResultStatus: None=0, Success=1, Failure=2, Blocked=3
    if (result.RootElement.TryGetProperty("Status", out var status))
        Console.WriteLine($"Save status: {status}");
    if (result.RootElement.TryGetProperty("Messages", out var messages))
    {
        foreach (var message in messages.EnumerateArray())
            Console.WriteLine($"  Message: {message}");
    }

    // ---- read-back: HTTP 200 alone does not mean the save landed ----------
    var readBackResponse = await client.GetAsync(
        $"{uiServer}/api/ui/interactive/v2/data?id={windowId}");
    readBackResponse.EnsureSuccessStatusCode();

    // /v2/data returns the datawindows of the ACTIVE tab, and only a subset of
    // them -- absence here is not proof that a field failed to save.
    var raw = await readBackResponse.Content.ReadAsStringAsync();
    Console.WriteLine(raw.Length > 2000 ? raw[..2000] : raw);
}
finally
{
    await client.DeleteAsync($"{uiServer}/api/ui/interactive/v2/window?id={windowId}");
    // Always end the session -- a leaked one blocks the next create with 409
    await client.DeleteAsync($"{uiServer}/api/ui/interactive/sessions");
}

// --- helpers ---------------------------------------------------------------

static StringContent Json(object payload) =>
    new(JsonSerializer.Serialize(payload), Encoding.UTF8, "application/json");

// v2 token endpoint — credentials go in the body, never in headers.
static async Task<string> GetTokenAsync(HttpClient client)
{
    var payload = JsonSerializer.Serialize(new { username = Username, password = Password });
    var response = await client.PostAsync(
        $"{BaseUrl}/api/security/token/v2",
        new StringContent(payload, Encoding.UTF8, "application/json"));
    response.EnsureSuccessStatusCode();
    return ReadField(await response.Content.ReadAsStringAsync(), "AccessToken");
}

// Transaction and Interactive calls go to the UI server, not BaseUrl.
static async Task<string> GetUiServerAsync(HttpClient client, string token)
{
    using var request = new HttpRequestMessage(
        HttpMethod.Get, $"{BaseUrl}/api/ui/router/v1/?urlType=external");
    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", token);
    var response = await client.SendAsync(request);
    response.EnsureSuccessStatusCode();
    return ReadField(await response.Content.ReadAsStringAsync(), "Url").TrimEnd('/');
}

// Some middleware answers these two endpoints in XML even when asked for JSON.
static string ReadField(string payload, string field)
{
    try
    {
        var value = JsonDocument.Parse(payload).RootElement.GetProperty(field).GetString();
        if (!string.IsNullOrEmpty(value)) return value;
    }
    catch (Exception ex) when (ex is JsonException or KeyNotFoundException) { }

    var match = System.Text.RegularExpressions.Regex.Match(payload, $"<{field}>([^<]+)</{field}>");
    if (!match.Success)
        throw new InvalidOperationException(
            $"No {field} in response: {payload[..Math.Min(200, payload.Length)]}");
    return match.Groups[1].Value;
}

// Correct - use display value
await ChangeAsync("VALUES", "values", "calculation_method_cd", "Mark Up");

// Incorrect - do not use code
await ChangeAsync("VALUES", "values", "calculation_method_cd", "229");

using System.Net.Http.Headers;
using System.Text;
using System.Text.Json;

// ---- EDIT THESE -----------------------------------------------------------
const string BaseUrl = "https://play.p21server.com";   // your P21 server
const string Username = "apiuser";
const string Password = "your-password";
const string PricePageUid = "45556";                   // an existing page to probe
const string DisplayValue = "Mark Up";                 // the dropdown label under test
// ---------------------------------------------------------------------------

var handler = new HttpClientHandler
{
    // Test tenants often present a self-signed cert. Delete this line in production.
    ServerCertificateCustomValidationCallback =
        HttpClientHandler.DangerousAcceptAnyServerCertificateValidator,
};
using var client = new HttpClient(handler) { Timeout = TimeSpan.FromMinutes(2) };
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));

var token = await GetTokenAsync(client);
var uiServer = await GetUiServerAsync(client, token);
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);

var sessionResponse = await client.PostAsync(
    $"{uiServer}/api/ui/interactive/sessions",
    Json(new { ResponseWindowHandlingEnabled = false }));
sessionResponse.EnsureSuccessStatusCode();

var openResponse = await client.PostAsync(
    $"{uiServer}/api/ui/interactive/v2/window",
    Json(new { ServiceName = "SalesPricePage" }));
openResponse.EnsureSuccessStatusCode();

using var opened = JsonDocument.Parse(await openResponse.Content.ReadAsStringAsync());
var windowId = opened.RootElement.GetProperty("WindowId").GetString()!;

// One field per call -- a batched /v2/change is non-atomic on 2026.1.
async Task ChangeAsync(string tab, string datawindow, string field, string value)
{
    var response = await client.PutAsync(
        $"{uiServer}/api/ui/interactive/v2/change",
        Json(new
        {
            WindowId = windowId,
            List = new[]
            {
                new
                {
                    TabName = tab,
                    DatawindowName = datawindow,     // required since 25.2
                    FieldName = field,
                    Value = value,
                }
            }
        }));
    response.EnsureSuccessStatusCode();
}

try
{
    // Load a specific price page, then move to the tab that owns the field
    await ChangeAsync("FORM", "form", "price_page_uid", PricePageUid);

    var tabResponse = await client.PutAsync(
        $"{uiServer}/api/ui/interactive/v2/tab",
        Json(new { WindowId = windowId, PageName = "VALUES" }));
    tabResponse.EnsureSuccessStatusCode();

    // Try setting a display value
    await ChangeAsync("VALUES", "values", "calculation_method_cd", DisplayValue);

    // Read the window state back and find the code the label resolved to
    var stateResponse = await client.GetAsync(
        $"{uiServer}/api/ui/interactive/v2/data?id={windowId}");
    stateResponse.EnsureSuccessStatusCode();

    // Shape varies by window -- dump it and locate calculation_method_cd
    var raw = await stateResponse.Content.ReadAsStringAsync();
    Console.WriteLine(raw.Length > 3000 ? raw[..3000] : raw);
}
finally
{
    await client.DeleteAsync($"{uiServer}/api/ui/interactive/v2/window?id={windowId}");
    await client.DeleteAsync($"{uiServer}/api/ui/interactive/sessions");
}

// --- helpers ---------------------------------------------------------------

static StringContent Json(object payload) =>
    new(JsonSerializer.Serialize(payload), Encoding.UTF8, "application/json");

// v2 token endpoint — credentials go in the body, never in headers.
static async Task<string> GetTokenAsync(HttpClient client)
{
    var payload = JsonSerializer.Serialize(new { username = Username, password = Password });
    var response = await client.PostAsync(
        $"{BaseUrl}/api/security/token/v2",
        new StringContent(payload, Encoding.UTF8, "application/json"));
    response.EnsureSuccessStatusCode();
    return ReadField(await response.Content.ReadAsStringAsync(), "AccessToken");
}

// Transaction and Interactive calls go to the UI server, not BaseUrl.
static async Task<string> GetUiServerAsync(HttpClient client, string token)
{
    using var request = new HttpRequestMessage(
        HttpMethod.Get, $"{BaseUrl}/api/ui/router/v1/?urlType=external");
    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", token);
    var response = await client.SendAsync(request);
    response.EnsureSuccessStatusCode();
    return ReadField(await response.Content.ReadAsStringAsync(), "Url").TrimEnd('/');
}

// Some middleware answers these two endpoints in XML even when asked for JSON.
static string ReadField(string payload, string field)
{
    try
    {
        var value = JsonDocument.Parse(payload).RootElement.GetProperty(field).GetString();
        if (!string.IsNullOrEmpty(value)) return value;
    }
    catch (Exception ex) when (ex is JsonException or KeyNotFoundException) { }

    var match = System.Text.RegularExpressions.Regex.Match(payload, $"<{field}>([^<]+)</{field}>");
    if (!match.Success)
        throw new InvalidOperationException(
            $"No {field} in response: {payload[..Math.Min(200, payload.Length)]}");
    return match.Groups[1].Value;
}

using System.Net.Http.Headers;
using System.Text;
using System.Text.Json;

// ---- EDIT THESE -----------------------------------------------------------
const string BaseUrl = "https://play.p21server.com";   // your P21 server
const string Username = "apiuser";
const string Password = "your-password";
const string PricePageUid = "45556";        // the page whose tiers you are setting
// ---------------------------------------------------------------------------

var handler = new HttpClientHandler
{
    // Test tenants often present a self-signed cert. Delete this line in production.
    ServerCertificateCustomValidationCallback =
        HttpClientHandler.DangerousAcceptAnyServerCertificateValidator,
};
using var client = new HttpClient(handler) { Timeout = TimeSpan.FromMinutes(2) };
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));

var token = await GetTokenAsync(client);
var uiServer = await GetUiServerAsync(client, token);
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);

var sessionResponse = await client.PostAsync(
    $"{uiServer}/api/ui/interactive/sessions",
    Json(new { ResponseWindowHandlingEnabled = false }));
sessionResponse.EnsureSuccessStatusCode();

var openResponse = await client.PostAsync(
    $"{uiServer}/api/ui/interactive/v2/window",
    Json(new { ServiceName = "SalesPricePage" }));
openResponse.EnsureSuccessStatusCode();

using var opened = JsonDocument.Parse(await openResponse.Content.ReadAsStringAsync());
var windowId = opened.RootElement.GetProperty("WindowId").GetString()!;

// One field per call -- a batched /v2/change is non-atomic on 2026.1.
async Task ChangeAsync(string tab, string datawindow, string field, string value)
{
    var response = await client.PutAsync(
        $"{uiServer}/api/ui/interactive/v2/change",
        Json(new
        {
            WindowId = windowId,
            List = new[]
            {
                new
                {
                    TabName = tab,
                    DatawindowName = datawindow,     // required since 25.2
                    FieldName = field,
                    Value = value,
                }
            }
        }));
    response.EnsureSuccessStatusCode();
}

try
{
    await ChangeAsync("FORM", "form", "price_page_uid", PricePageUid);

    var tabResponse = await client.PutAsync(
        $"{uiServer}/api/ui/interactive/v2/tab",
        Json(new { WindowId = windowId, PageName = "VALUES" }));
    tabResponse.EnsureSuccessStatusCode();

    // Base multiplier: 0.85 for qty 1+
    await ChangeAsync("VALUES", "values", "calculation_value1", "0.85");

    // Price break at qty 6: 0.82 multiplier
    await ChangeAsync("VALUES", "values", "break1", "6");
    await ChangeAsync("VALUES", "values", "calculation_value2", "0.82");

    // Price break at qty 25: 0.78 multiplier
    await ChangeAsync("VALUES", "values", "break2", "25");
    await ChangeAsync("VALUES", "values", "calculation_value3", "0.78");

    // Price break at qty 100: 0.75 multiplier
    await ChangeAsync("VALUES", "values", "break3", "100");
    await ChangeAsync("VALUES", "values", "calculation_value4", "0.75");

    // Save -- v2 takes the bare WindowId string as the JSON body
    var saveResponse = await client.PutAsync(
        $"{uiServer}/api/ui/interactive/v2/data", Json(windowId));
    saveResponse.EnsureSuccessStatusCode();

    using var result = JsonDocument.Parse(await saveResponse.Content.ReadAsStringAsync());
    // ResultStatus: None=0, Success=1, Failure=2, Blocked=3
    if (result.RootElement.TryGetProperty("Status", out var status))
        Console.WriteLine($"Save status: {status}");
    if (result.RootElement.TryGetProperty("Messages", out var messages))
    {
        foreach (var message in messages.EnumerateArray())
            Console.WriteLine($"  Message: {message}");
    }

    // ---- read-back: the only proof the tiers landed ------------------------
    var readBackResponse = await client.GetAsync(
        $"{uiServer}/api/ui/interactive/v2/data?id={windowId}");
    readBackResponse.EnsureSuccessStatusCode();

    var raw = await readBackResponse.Content.ReadAsStringAsync();
    Console.WriteLine(raw.Length > 2000 ? raw[..2000] : raw);
}
finally
{
    await client.DeleteAsync($"{uiServer}/api/ui/interactive/v2/window?id={windowId}");
    await client.DeleteAsync($"{uiServer}/api/ui/interactive/sessions");
}

// --- helpers ---------------------------------------------------------------

static StringContent Json(object payload) =>
    new(JsonSerializer.Serialize(payload), Encoding.UTF8, "application/json");

// v2 token endpoint — credentials go in the body, never in headers.
static async Task<string> GetTokenAsync(HttpClient client)
{
    var payload = JsonSerializer.Serialize(new { username = Username, password = Password });
    var response = await client.PostAsync(
        $"{BaseUrl}/api/security/token/v2",
        new StringContent(payload, Encoding.UTF8, "application/json"));
    response.EnsureSuccessStatusCode();
    return ReadField(await response.Content.ReadAsStringAsync(), "AccessToken");
}

// Transaction and Interactive calls go to the UI server, not BaseUrl.
static async Task<string> GetUiServerAsync(HttpClient client, string token)
{
    using var request = new HttpRequestMessage(
        HttpMethod.Get, $"{BaseUrl}/api/ui/router/v1/?urlType=external");
    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", token);
    var response = await client.SendAsync(request);
    response.EnsureSuccessStatusCode();
    return ReadField(await response.Content.ReadAsStringAsync(), "Url").TrimEnd('/');
}

// Some middleware answers these two endpoints in XML even when asked for JSON.
static string ReadField(string payload, string field)
{
    try
    {
        var value = JsonDocument.Parse(payload).RootElement.GetProperty(field).GetString();
        if (!string.IsNullOrEmpty(value)) return value;
    }
    catch (Exception ex) when (ex is JsonException or KeyNotFoundException) { }

    var match = System.Text.RegularExpressions.Regex.Match(payload, $"<{field}>([^<]+)</{field}>");
    if (!match.Success)
        throw new InvalidOperationException(
            $"No {field} in response: {payload[..Math.Min(200, payload.Length)]}");
    return match.Groups[1].Value;
}

using System.Net.Http.Headers;
using System.Text;
using System.Text.Json;

// ---- EDIT THESE -----------------------------------------------------------
const string BaseUrl = "https://play.p21server.com";   // your P21 server
const string Username = "apiuser";
const string Password = "your-password";
const string CompanyId = "ACME";
const string DiscountGroupId = "DG001";     // replaces product_group_id on type 213
const string SupplierId = "10050";
const string Description = "P2-L5-10050-DG001-WHOLESALE";
const string EffectiveDate = "2025-01-01";
const string ExpirationDate = "2030-12-31";
const string Multiplier = "0.85";           // calculation_value1 -- tier 1, qty 1+
// ---------------------------------------------------------------------------

var handler = new HttpClientHandler
{
    // Test tenants often present a self-signed cert. Delete this line in production.
    ServerCertificateCustomValidationCallback =
        HttpClientHandler.DangerousAcceptAnyServerCertificateValidator,
};
using var client = new HttpClient(handler) { Timeout = TimeSpan.FromMinutes(2) };
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));

var token = await GetTokenAsync(client);
var uiServer = await GetUiServerAsync(client, token);
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);

var sessionResponse = await client.PostAsync(
    $"{uiServer}/api/ui/interactive/sessions",
    Json(new { ResponseWindowHandlingEnabled = false }));
sessionResponse.EnsureSuccessStatusCode();

var openResponse = await client.PostAsync(
    $"{uiServer}/api/ui/interactive/v2/window",
    Json(new { ServiceName = "SalesPricePage" }));
openResponse.EnsureSuccessStatusCode();

using var opened = JsonDocument.Parse(await openResponse.Content.ReadAsStringAsync());
var windowId = opened.RootElement.GetProperty("WindowId").GetString()!;

// One field per call -- a batched /v2/change is non-atomic on 2026.1.
async Task ChangeAsync(string tab, string datawindow, string field, string value)
{
    var response = await client.PutAsync(
        $"{uiServer}/api/ui/interactive/v2/change",
        Json(new
        {
            WindowId = windowId,
            List = new[]
            {
                new
                {
                    TabName = tab,
                    DatawindowName = datawindow,     // required since 25.2
                    FieldName = field,
                    Value = value,
                }
            }
        }));
    response.EnsureSuccessStatusCode();
}

try
{
    // Step 1: page type to Discount Group
    await ChangeAsync("FORM", "form", "price_page_type_cd", "Supplier / Discount Group");

    // Step 2: company_id first
    await ChangeAsync("FORM", "form", "company_id", CompanyId);

    // Step 3: discount group (NOT product_group_id)
    await ChangeAsync("FORM", "form", "discount_group_id", DiscountGroupId);

    // Step 4: supplier
    await ChangeAsync("FORM", "form", "supplier_id", SupplierId);

    // Steps 5-8: same as a product group page
    await ChangeAsync("FORM", "form", "description", Description);
    await ChangeAsync("FORM", "form", "pricing_method_cd", "Source");
    await ChangeAsync("FORM", "form", "source_price_cd", "Supplier List Price");
    await ChangeAsync("FORM", "form", "effective_date", EffectiveDate);
    await ChangeAsync("FORM", "form", "expiration_date", ExpirationDate);

    // Step 9: switch to the VALUES tab (2026.1 binds PageName, not TabName)
    var tabResponse = await client.PutAsync(
        $"{uiServer}/api/ui/interactive/v2/tab",
        Json(new { WindowId = windowId, PageName = "VALUES" }));
    tabResponse.EnsureSuccessStatusCode();

    // Step 10: calculation method and values
    await ChangeAsync("VALUES", "values", "calculation_method_cd", "Multiplier");
    await ChangeAsync("VALUES", "values", "calculation_value1", Multiplier);

    // Save -- v2 takes the bare WindowId string as the JSON body
    var saveResponse = await client.PutAsync(
        $"{uiServer}/api/ui/interactive/v2/data", Json(windowId));
    saveResponse.EnsureSuccessStatusCode();

    using var result = JsonDocument.Parse(await saveResponse.Content.ReadAsStringAsync());
    // ResultStatus: None=0, Success=1, Failure=2, Blocked=3
    if (result.RootElement.TryGetProperty("Status", out var status))
        Console.WriteLine($"Save status: {status}");
    if (result.RootElement.TryGetProperty("Messages", out var messages))
    {
        foreach (var message in messages.EnumerateArray())
            Console.WriteLine($"  Message: {message}");
    }

    // ---- read-back: the only proof the page landed -------------------------
    var readBackResponse = await client.GetAsync(
        $"{uiServer}/api/ui/interactive/v2/data?id={windowId}");
    readBackResponse.EnsureSuccessStatusCode();

    var raw = await readBackResponse.Content.ReadAsStringAsync();
    Console.WriteLine(raw.Length > 2000 ? raw[..2000] : raw);
}
finally
{
    await client.DeleteAsync($"{uiServer}/api/ui/interactive/v2/window?id={windowId}");
    await client.DeleteAsync($"{uiServer}/api/ui/interactive/sessions");
}

// --- helpers ---------------------------------------------------------------

static StringContent Json(object payload) =>
    new(JsonSerializer.Serialize(payload), Encoding.UTF8, "application/json");

// v2 token endpoint — credentials go in the body, never in headers.
static async Task<string> GetTokenAsync(HttpClient client)
{
    var payload = JsonSerializer.Serialize(new { username = Username, password = Password });
    var response = await client.PostAsync(
        $"{BaseUrl}/api/security/token/v2",
        new StringContent(payload, Encoding.UTF8, "application/json"));
    response.EnsureSuccessStatusCode();
    return ReadField(await response.Content.ReadAsStringAsync(), "AccessToken");
}

// Transaction and Interactive calls go to the UI server, not BaseUrl.
static async Task<string> GetUiServerAsync(HttpClient client, string token)
{
    using var request = new HttpRequestMessage(
        HttpMethod.Get, $"{BaseUrl}/api/ui/router/v1/?urlType=external");
    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", token);
    var response = await client.SendAsync(request);
    response.EnsureSuccessStatusCode();
    return ReadField(await response.Content.ReadAsStringAsync(), "Url").TrimEnd('/');
}

// Some middleware answers these two endpoints in XML even when asked for JSON.
static string ReadField(string payload, string field)
{
    try
    {
        var value = JsonDocument.Parse(payload).RootElement.GetProperty(field).GetString();
        if (!string.IsNullOrEmpty(value)) return value;
    }
    catch (Exception ex) when (ex is JsonException or KeyNotFoundException) { }

    var match = System.Text.RegularExpressions.Regex.Match(payload, $"<{field}>([^<]+)</{field}>");
    if (!match.Success)
        throw new InvalidOperationException(
            $"No {field} in response: {payload[..Math.Min(200, payload.Length)]}");
    return match.Groups[1].Value;
}