using System.Net;
using System.Text;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.Logging.Abstractions;
using w4c_workflows.Services.Execution;
using Xunit;

namespace w4c_workflows.Tests;

/// <summary>
/// The remote (SSH) executor stages the task script on the target server. These
/// tests pin the generated shell: the staged file must be removed on every
/// completion path and the interpreter's exit code must still be propagated.
/// </summary>
public class RemoteServerExecutorTests
{
    private sealed class CapturingHandler : HttpMessageHandler
    {
        public string? LastBody { get; private set; }

        protected override async Task<HttpResponseMessage> SendAsync(
            HttpRequestMessage request, CancellationToken cancellationToken)
        {
            if (request.Content != null)
                LastBody = await request.Content.ReadAsStringAsync(cancellationToken);
            return new HttpResponseMessage(HttpStatusCode.OK)
            {
                Content = new StringContent(
                    "{\"exitCode\":0,\"stdout\":\"ok\",\"stderr\":\"\",\"timedOut\":false}",
                    Encoding.UTF8, "application/json"),
            };
        }
    }

    private sealed class Factory : IHttpClientFactory
    {
        private readonly HttpMessageHandler _handler;
        public Factory(HttpMessageHandler handler) => _handler = handler;
        public HttpClient CreateClient(string name) => new(_handler, disposeHandler: false);
    }

    [Fact]
    public async Task Staged_script_is_removed_and_exit_code_propagated()
    {
        var workDir = Directory.CreateTempSubdirectory("w4c-remote-");
        try
        {
            await File.WriteAllTextAsync(Path.Combine(workDir.FullName, "main.sh"), "echo hi");
            var handler = new CapturingHandler();
            var config = new ConfigurationBuilder()
                .AddInMemoryCollection(new Dictionary<string, string?>
                {
                    ["Workflows:ServerApiUrl"] = "http://server",
                })
                .Build();
            var executor = new RemoteServerExecutor(
                new Factory(handler), config, NullLogger<RemoteServerExecutor>.Instance);

            var invocation = new TaskInvocation(
                TaskInvocation.TypeValue, "run-1", "task-12345678", "key", "shell", "main.sh", null,
                new Dictionary<string, string>(), null, workDir.FullName, "tenant-1", 1, "srv-1");

            var result = await executor.ExecuteAsync(invocation, default);

            Assert.True(result.Success);
            Assert.NotNull(handler.LastBody);
            Assert.Contains(".w4c-run-", handler.LastBody);
            Assert.Contains("rm -f", handler.LastBody);
            Assert.Contains("exit $rc", handler.LastBody);
        }
        finally
        {
            workDir.Delete(recursive: true);
        }
    }

    [Fact]
    public async Task Typescript_is_rejected_for_remote_with_a_clear_error()
    {
        var workDir = Directory.CreateTempSubdirectory("w4c-remote-ts-");
        try
        {
            await File.WriteAllTextAsync(
                Path.Combine(workDir.FullName, "main.ts"), "const value: number = 1;");
            var handler = new CapturingHandler();
            var config = new ConfigurationBuilder()
                .AddInMemoryCollection(new Dictionary<string, string?>
                {
                    ["Workflows:ServerApiUrl"] = "http://server",
                })
                .Build();
            var executor = new RemoteServerExecutor(
                new Factory(handler), config, NullLogger<RemoteServerExecutor>.Instance);

            var invocation = new TaskInvocation(
                TaskInvocation.TypeValue, "run-1", "task-12345678", "key", "typescript", "main.ts", null,
                new Dictionary<string, string>(), null, workDir.FullName, "tenant-1", 1, "srv-1");

            var result = await executor.ExecuteAsync(invocation, default);

            Assert.False(result.Success);
            Assert.NotNull(result.Error);
            Assert.Contains("typescript", result.Error);
            Assert.Contains("not supported", result.Error);
            // Raw TypeScript must never be shipped to a remote `node`: the local
            // path bundles it with esbuild first, and nothing is sent here.
            Assert.Null(handler.LastBody);
        }
        finally
        {
            workDir.Delete(recursive: true);
        }
    }
}