using System.Text.Json;
using Microsoft.Extensions.AI;
using ModelContextProtocol.Client;
using ModelContextProtocol.Protocol;

string endpoint = Environment.GetEnvironmentVariable("MCP_ENDPOINT")
    ?? throw new InvalidOperationException(
        "Set MCP_ENDPOINT to your reviewed https://.../mcp endpoint.");

static Dictionary<string, object?> Args(params (string Name, object? Value)[] values)
    => values.ToDictionary(value => value.Name, value => value.Value);

var transport = new HttpClientTransport(new HttpClientTransportOptions
{
    Endpoint = new Uri(endpoint),
    Name = "open-for-agents",
    TransportMode = HttpTransportMode.StreamableHttp,
    ConnectionTimeout = TimeSpan.FromSeconds(20),
    OwnsSession = false,
});

await using McpClient client = await McpClient.CreateAsync(transport);
IList<McpClientTool> tools = await client.ListToolsAsync();

foreach (McpClientTool tool in tools)
{
    Tool protocolTool = tool.ProtocolTool;
    if (protocolTool.Annotations?.ReadOnlyHint != true ||
        protocolTool.Annotations?.OpenWorldHint != false ||
        tool is not AIFunction)
    {
        throw new InvalidOperationException(
            $"Unexpected metadata for {tool.Name}.");
    }
}

var calls = new Dictionary<string, CallToolResult>
{
    ["get_site_info"] = await client.CallToolAsync("get_site_info"),
    ["list_posts"] =
        await client.CallToolAsync("list_posts", Args(("per_page", 3))),
    ["woo_search_products"] =
        await client.CallToolAsync("woo_search_products", Args(("per_page", 3))),
};
if (calls.Values.Any(result => result.IsError == true))
{
    throw new InvalidOperationException("A representative read returned an error.");
}

CallToolResult large = await client.CallToolAsync(
    "woo_search_products",
    Args(("per_page", 6)));
if (large.IsError == true ||
    large.Content.FirstOrDefault() is not TextContentBlock textBlock)
{
    throw new InvalidOperationException("The large read was not successful.");
}

string[] textParts = textBlock.Text.Split("\n\n", 2);
using JsonDocument projection = JsonDocument.Parse(textParts[1]);
JsonElement bounded =
    projection.RootElement.GetProperty("_open_for_agents");
if (!bounded.GetProperty("truncated").GetBoolean() ||
    bounded.GetProperty("reason").GetString() != "output_budget" ||
    bounded.GetProperty("max_chars").GetInt32() != 1500)
{
    throw new InvalidOperationException(
        "The bounded output contract did not match.");
}

Console.WriteLine(JsonSerializer.Serialize(new
{
    endpoint,
    tools = tools.Select(tool => new
    {
        tool.Name,
        annotations = tool.ProtocolTool.Annotations,
        agentFrameworkFunction = tool is AIFunction,
    }),
    representativeCalls = calls.ToDictionary(
        item => item.Key,
        item => item.Value.StructuredContent),
    boundedOutput = JsonSerializer.Deserialize<object>(bounded.GetRawText()),
}, new JsonSerializerOptions { WriteIndented = true }));