using System;
using System.IO;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading.Tasks;
using CsharpHttpHelper;
using Work.Store.Api;

// Compile against Work.dll, AllBase.dll and Newtonsoft.Json.dll; run beside these assemblies.
internal static class ApiTransportSmoke
{
    private static void Check(bool passed)
    {
        if (!passed) throw new Exception("ApiTransport assertion failed.");
    }

    private static async Task<T> Respond<T>(int status, string json, Func<ApiTransport, Task<T>> request)
    {
        var listener = new TcpListener(IPAddress.Loopback, 0);
        listener.Start();
        var server = Task.Run(() =>
        {
            using (var client = listener.AcceptTcpClient())
            using (var stream = client.GetStream())
            using (var reader = new StreamReader(stream, Encoding.ASCII, false, 1024, true))
            {
                while (!string.IsNullOrEmpty(reader.ReadLine())) { }
                var body = Encoding.UTF8.GetBytes(json);
                var header = Encoding.ASCII.GetBytes("HTTP/1.1 " + status + " Response\r\nContent-Type: application/json\r\nContent-Length: " + body.Length + "\r\nConnection: close\r\n\r\n");
                stream.Write(header, 0, header.Length);
                stream.Write(body, 0, body.Length);
            }
        });
        try
        {
            var port = ((IPEndPoint)listener.LocalEndpoint).Port;
            return await request(new ApiTransport("http://127.0.0.1:" + port));
        }
        finally
        {
            listener.Stop();
            await server;
        }
    }

    private static Task<string> Send(ApiTransport transport)
    {
        return transport.SendAsync<string>("Test", MethodType.Get, authenticated: false, timeoutMilliseconds: 5000);
    }

    public static async Task Main()
    {
        Check(await Respond(200, "{\"code\":0,\"success\":true,\"data\":\"ok\"}", Send) == "ok");
        Check(await Respond(200, "{\"code\":0,\"success\":true,\"data\":null}", Send) == null);
        Check(await Respond(200, "{\"success\":true,\"data\":null}", transport =>
            transport.SendAsync<int>("Test", MethodType.Get, authenticated: false)) == 0);
        Check((await Respond(200, "{\"success\":true,\"data\":[1,2]}", transport =>
            transport.SendAsync<int[]>("Test", MethodType.Get, authenticated: false)))[1] == 2);
        foreach (var status in new[] { 200, 500 })
        {
            await Respond(status, "{\"data\":null,\"code\":5000,\"msg\":\"semaphore limit\",\"traceId\":\"trace-1\",\"success\":false}", async transport =>
            {
                try { await Send(transport); throw new Exception("Expected ApiException."); }
                catch (ApiException ex)
                {
                    Check(ex.Code == 5000 && ex.TraceId == "trace-1" && ex.Message.Contains("semaphore limit"));
                }
                return true;
            });
        }
        await Respond(200, "{\"code\":200,\"success\":false,\"data\":{}}", async transport =>
        {
            try { await Send(transport); throw new Exception("Expected ApiException."); }
            catch (ApiException ex) { Check(ex.Code == 200 && ex.ResponseData is Newtonsoft.Json.Linq.JObject); }
            return true;
        });
        foreach (var json in new[] { "not json", "[]", "null", "{\"code\":\"invalid\",\"success\":true}",
            "{\"code\":200,\"data\":\"legacy\"}", "{\"code\":200,\"success\":null}", "{}" })
        {
            await Respond(200, json, async transport =>
            {
                try { await Send(transport); throw new Exception("Expected response format error."); }
                catch (HttpException ex) { Check(ex.Message.Contains("Result")); }
                return true;
            });
        }
        await Respond(401, "{\"code\":401,\"success\":false,\"msg\":\"expired\"}", async transport =>
        {
            try { await Send(transport); throw new Exception("Expected authentication error."); }
            catch (HttpException ex) { Check(!ex.IsOnline && ex.Message == "expired"); }
            return true;
        });
        Check(await Respond(200, "{\"success\":true,\"data\":\"ok\"}", transport =>
            Task.Run(() => transport.GetRequired<string>("Test", MethodType.Get, authenticated: false))) == "ok");

        var stalled = new TcpListener(IPAddress.Loopback, 0);
        stalled.Start();
        try
        {
            var transport = new ApiTransport("http://" + stalled.LocalEndpoint);
            try
            {
                await transport.SendAsync<string>("Test", MethodType.Get, authenticated: false, timeoutMilliseconds: 250);
                throw new Exception("Expected timeout.");
            }
            catch (HttpException ex) { Check(ex.Message.Contains("超时")); }
        }
        finally { stalled.Stop(); }
        Console.WriteLine("ApiTransport smoke checks passed.");
    }
}