using System.CommandLine;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Text.Json;
using ZB.MOM.WW.ScadaBridge.CLI.Commands;

namespace ZB.MOM.WW.ScadaBridge.CLI.Tests;

/// <summary>
/// <c>deploy area</c> (Gitea #40) sends <c>MgmtDeployArea</c> with the area id and
/// force flag, and derives its exit code from the summary's <c>failureCount</c>
/// exactly like <c>deploy site</c>: a per-instance failure is a successful HTTP
/// call, so without that a script could not detect it.
/// </summary>
public class DeployAreaExitCodeTests
{
    /// <summary>Verifies the wire payload and the exit code derived from the summary.</summary>
    /// <param name="response">The JSON response body served by the fake management endpoint.</param>
    /// <param name="force">Whether <c>--force</c> is passed.</param>
    /// <param name="expected">The expected process exit code.</param>
    /// <returns>A task that represents the asynchronous operation.</returns>
    [Theory]
    [InlineData("{\"successCount\":2,\"failureCount\":0}", false, 0)]
    [InlineData("{\"successCount\":1,\"failureCount\":1}", true, 1)]
    [InlineData("{\"unexpected\":true}", false, 1)]
    public async Task DeployArea_SendsAreaCommand_AndReturnsDomainExitCode(string response, bool force, int expected)
    {
        var listener = new TcpListener(IPAddress.Loopback, 0);
        listener.Start();
        try
        {
            var port = ((IPEndPoint)listener.LocalEndpoint).Port;
            string? requestBody = null;
            var server = Task.Run(async () =>
            {
                using var client = await listener.AcceptTcpClientAsync();
                await using var stream = client.GetStream();
                using var reader = new StreamReader(stream, Encoding.UTF8, leaveOpen: true);
                var length = 0;
                while (await reader.ReadLineAsync() is { Length: > 0 } line)
                    if (line.StartsWith("Content-Length:", StringComparison.OrdinalIgnoreCase))
                        length = int.Parse(line[15..].Trim());
                var buffer = new char[length];
                var read = 0;
                while (read < length)
                {
                    var count = await reader.ReadAsync(buffer.AsMemory(read));
                    if (count == 0) throw new EndOfStreamException();
                    read += count;
                }
                requestBody = new string(buffer);
                var body = Encoding.UTF8.GetBytes(response);
                var headers = Encoding.ASCII.GetBytes($"HTTP/1.1 200 OK\r\nContent-Type: application/json\r\nContent-Length: {body.Length}\r\nConnection: close\r\n\r\n");
                await stream.WriteAsync(headers);
                await stream.WriteAsync(body);
            });
            var root = new RootCommand();
            var url = new Option<string>("--url") { Recursive = true };
            var format = new Option<string>("--format") { Recursive = true };
            var user = new Option<string>("--username") { Recursive = true };
            var password = new Option<string>("--password") { Recursive = true };
            root.Add(url); root.Add(format); root.Add(user); root.Add(password);
            root.Add(DeployCommands.Build(url, format, user, password));
            string[] args = ["deploy", "area", "--id", "12", "--url", $"http://127.0.0.1:{port}",
                "--username", "test", "--password", "test", "--format", "json"];
            if (force) args = [.. args, "--force"];
            var exit = await root.Parse(args).InvokeAsync();
            await server.WaitAsync(TimeSpan.FromSeconds(5));

            Assert.Equal(expected, exit);
            using var payload = JsonDocument.Parse(requestBody!);
            Assert.Equal("MgmtDeployArea", payload.RootElement.GetProperty("command").GetString());
            var command = payload.RootElement.GetProperty("payload");
            Assert.Equal(12, GetPropertyIgnoreCase(command, "areaId").GetInt32());
            Assert.Equal(force, GetPropertyIgnoreCase(command, "force").GetBoolean());
        }
        finally { listener.Stop(); }
    }

    private static JsonElement GetPropertyIgnoreCase(JsonElement element, string name) =>
        element.EnumerateObject().First(p => string.Equals(p.Name, name, StringComparison.OrdinalIgnoreCase)).Value;
}