using System.Net;
using System.Net.Http.Json;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Hosting.Server;
using Microsoft.AspNetCore.Hosting.Server.Features;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Shouldly;
using Xunit;
using ZB.MOM.WW.OtOpcUa.AdminUI.Api;
using ZB.MOM.WW.OtOpcUa.Commons.Interfaces;
using ZB.MOM.WW.OtOpcUa.Commons.Messages.Admin;
using ZB.MOM.WW.OtOpcUa.Commons.Types;
using ZB.MOM.WW.OtOpcUa.Configuration;
using ZB.MOM.WW.OtOpcUa.Host.Configuration;

namespace ZB.MOM.WW.OtOpcUa.Host.IntegrationTests;

/// <summary>
///     lmxopcua#761 (2026-11-12 gate run): the headless deploy POST must accept a request with NO body, as
///     docker-dev/deploy.sh and the README document. It answered 404 on the rig: an inferred optional JSON
///     body put Accepts(application/json) metadata on the endpoint, and for a request with no Content-Type
///     the AcceptsMatcherPolicy routed to grpc-dotnet's unimplemented-service catch-all instead. The host is
///     composed like a fused admin+driver node (deploy API + mesh gRPC services) and driven over real HTTP,
///     so routing and the matcher policies all take part — the deploy API alone does not reproduce it.
/// </summary>
[Trait("Category", "Unit")]
public sealed class DeployApiBodylessPostTests
{
    private const string Key = "test-deploy-key";

    [Theory]
    [InlineData(false, false)]   // no body, no Content-Length header at all
    [InlineData(true, false)]    // Content-Length: 0
    [InlineData(true, true)]     // a JSON body (positive control)
    public async Task Post_without_a_body_is_accepted(bool contentLengthZero, bool jsonBody)
    {
        var ct = TestContext.Current.CancellationToken;
        var ops = new RecordingAdminOps();
        await using var app = await StartAsync(ops, ct);
        using var http = new HttpClient { BaseAddress = new Uri(Address(app)) };

        using var req = new HttpRequestMessage(HttpMethod.Post, "/api/deployments");
        req.Headers.Add(DeployApiEndpoints.ApiKeyHeader, Key);
        if (jsonBody) req.Content = JsonContent.Create(new { createdBy = "ci-bot" });
        else if (contentLengthZero) req.Content = new ByteArrayContent([]);

        using var resp = await http.SendAsync(req, ct);

        resp.StatusCode.ShouldBe(HttpStatusCode.Accepted, await resp.Content.ReadAsStringAsync(ct));
        ops.CreatedBy.ShouldBe(jsonBody ? "ci-bot" : "rest-api");
    }

    [Theory]
    [InlineData("text/plain", "hello", HttpStatusCode.UnsupportedMediaType)]
    [InlineData("application/json", "{not json", HttpStatusCode.BadRequest)]
    public async Task Post_with_an_unusable_body_is_refused_without_deploying(
        string contentType, string content, HttpStatusCode expected)
    {
        var ct = TestContext.Current.CancellationToken;
        var ops = new RecordingAdminOps();
        await using var app = await StartAsync(ops, ct);
        using var http = new HttpClient { BaseAddress = new Uri(Address(app)) };

        using var req = new HttpRequestMessage(HttpMethod.Post, "/api/deployments")
        {
            Content = new StringContent(content, System.Text.Encoding.UTF8, contentType),
        };
        req.Headers.Add(DeployApiEndpoints.ApiKeyHeader, Key);

        using var resp = await http.SendAsync(req, ct);

        resp.StatusCode.ShouldBe(expected);
        ops.CreatedBy.ShouldBeNull();
    }

    private static async Task<WebApplication> StartAsync(IAdminOperationsClient ops, CancellationToken ct)
    {
        var builder = WebApplication.CreateBuilder();
        builder.WebHost.UseUrls("http://127.0.0.1:0");
        builder.Services.AddSingleton(ops);
        builder.Services.AddAuthorization();
        builder.Services.AddGrpc();
        builder.Services.AddDbContextFactory<OtOpcUaConfigDbContext>(o => o.UseInMemoryDatabase("deploy-api-bodyless"));
        var app = builder.Build();
        app.UseAuthorization();
        var config = new ConfigurationBuilder()
            .AddInMemoryCollection(new Dictionary<string, string?> { [DeployApiEndpoints.ConfigKey] = Key })
            .Build();
        app.MapOtOpcUaDeployApi(config);
        // Composed exactly as Program.cs does on a fused admin+driver node: the mesh gRPC services are
        // mapped AFTER the deploy API, and every MapGrpcService adds grpc-dotnet catch-all routes.
        app.MapOtOpcUaMeshGrpcServices(hasAdmin: true, hasDriver: true, syncListenPort: 9001,
            configServeGrpcPort: 4055, telemetryListenPort: 4056);
        await app.StartAsync(ct);
        return app;
    }

    private static string Address(WebApplication app) =>
        app.Services.GetRequiredService<IServer>().Features.Get<IServerAddressesFeature>()!.Addresses.First();

    private sealed class RecordingAdminOps : IAdminOperationsClient
    {
        public string? CreatedBy { get; private set; }

        public Task<StartDeploymentResult> StartDeploymentAsync(string createdBy, CancellationToken ct)
        {
            CreatedBy = createdBy;
            return Task.FromResult(new StartDeploymentResult(
                StartDeploymentOutcome.Accepted, new DeploymentId(Guid.NewGuid()), new RevisionHash("rev"), null,
                CorrelationId.NewId()));
        }

        public Task<AcknowledgeAlarmResult> AcknowledgeAlarmAsync(string alarmId, string user, string? comment, CancellationToken ct) =>
            throw new NotSupportedException();

        public Task<ShelveAlarmResult> ShelveAlarmAsync(string alarmId, string user, ShelveKind kind, DateTime? unshelveAtUtc,
            string? comment, CancellationToken ct) => throw new NotSupportedException();

        public Task<T> AskAsync<T>(object message, CancellationToken ct) => throw new NotSupportedException();
    }
}