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.Commands;

/// <summary>
/// Tests for <c>scadabridge audit archive list</c> / <c>verify</c> (ScadaBridge#42): each
/// sends its management command (<c>ListAuditArchives</c>, <c>VerifyAuditArchive</c>), and
/// <c>verify</c> maps the verdict onto the exit code (0 verified, 3 not verified).
/// </summary>
[Collection("Console")]
public class AuditArchiveCommandTests
{
    private const string Name = "auditlog-2025-10-20261109T120000123Z";

    private const string ListBody =
        "{\"enabled\":true,\"archives\":[{\"name\":\"" + Name + "\",\"partition\":\"2025-10\",\"status\":\"Purged\"," +
        "\"rowCount\":11,\"chainedRowCount\":10,\"dataBytes\":4096}]}";

    private const string VerifiedBody =
        "{\"name\":\"" + Name + "\",\"partition\":\"2025-10\",\"manifestStatus\":\"Purged\",\"verified\":true,\"filesIntact\":true," +
        "\"rowsRead\":11,\"chains\":[{\"chain\":{\"partition\":\"2025-10\",\"status\":\"Intact\",\"rowsVerified\":10," +
        "\"tombstonesApplied\":2,\"unchainedRows\":1},\"anchor\":\"Matches\",\"anchorDetail\":\"ends at the anchor\"}]}";

    private const string MismatchBody =
        "{\"name\":\"" + Name + "\",\"partition\":\"2025-10\",\"manifestStatus\":\"Purged\",\"verified\":false,\"filesIntact\":true," +
        "\"rowsRead\":11,\"chains\":[{\"chain\":{\"partition\":\"2025-10\",\"status\":\"Intact\",\"rowsVerified\":10," +
        "\"tombstonesApplied\":0,\"unchainedRows\":0},\"anchor\":\"Mismatch\",\"anchorDetail\":\"hash differs\"}]}";

    /// <summary>The audit group carries the archive group with list + verify.</summary>
    [Fact]
    public void AuditGroup_HasArchiveListAndVerify()
    {
        var root = AuditCommandTestHarness.BuildRoot();
        var archive = root.Subcommands.Single(c => c.Name == "audit").Subcommands.Single(c => c.Name == "archive");
        Assert.Equal(["list", "verify"], archive.Subcommands.Select(c => c.Name).Order());
    }

    /// <summary><c>list</c> sends ListAuditArchives and prints the archives.</summary>
    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task List_SendsListAuditArchives_AndPrintsTheArchives()
    {
        var (exit, output, request) = await RunAsync(ListBody, "audit", "archive", "list", "--format", "table");

        Assert.Equal(0, exit);
        Assert.Contains(Name, output);
        Assert.Contains("Archiving: enabled", output);
        using var payload = JsonDocument.Parse(request);
        Assert.Equal("ListAuditArchives", payload.RootElement.GetProperty("command").GetString());
    }

    /// <summary><c>verify</c> sends VerifyAuditArchive with the name and maps the verdict to the exit code.</summary>
    /// <param name="body">The verification result the fake endpoint serves.</param>
    /// <param name="format">Output format.</param>
    /// <param name="expectedExit">Expected exit code.</param>
    /// <param name="expectedText">Text the report must contain.</param>
    /// <returns>A task that represents the asynchronous operation.</returns>
    [Theory]
    [InlineData(VerifiedBody, "table", 0, "anchor Matches")]
    [InlineData(VerifiedBody, "json", 0, "\"verified\":true")]
    [InlineData(MismatchBody, "table", 3, "Verified    : NO")]
    [InlineData(MismatchBody, "json", 3, "\"anchor\":\"Mismatch\"")]
    public async Task Verify_SendsVerifyAuditArchive_AndMapsVerdictToExitCode(
        string body, string format, int expectedExit, string expectedText)
    {
        var (exit, output, request) = await RunAsync(body, "audit", "archive", "verify", "--name", Name, "--format", format);

        Assert.Equal(expectedExit, exit);
        Assert.Contains(expectedText, output);
        using var payload = JsonDocument.Parse(request);
        Assert.Equal("VerifyAuditArchive", payload.RootElement.GetProperty("command").GetString());
        var name = payload.RootElement.GetProperty("payload").EnumerateObject()
            .First(p => string.Equals(p.Name, "name", StringComparison.OrdinalIgnoreCase)).Value.GetString();
        Assert.Equal(Name, name);
    }

    /// <summary><c>verify</c> without <c>--name</c> is a usage error.</summary>
    [Fact]
    public void Verify_MissingName_ProducesRequiredFlagError()
    {
        var root = AuditCommandTestHarness.BuildRoot();
        var (exit, _, err) = AuditCommandTestHarness.Invoke(root, "audit", "archive", "verify");

        Assert.NotEqual(0, exit);
        Assert.Contains("--name", err);
    }

    private static async Task<(int Exit, string Output, string Request)> RunAsync(string body, params string[] args)
    {
        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 bytes = Encoding.UTF8.GetBytes(body);
                var headers = Encoding.ASCII.GetBytes(
                    $"HTTP/1.1 200 OK\r\nContent-Type: application/json\r\nContent-Length: {bytes.Length}\r\nConnection: close\r\n\r\n");
                await stream.WriteAsync(headers);
                await stream.WriteAsync(bytes);
            });

            var root = AuditCommandTestHarness.BuildRoot();
            var (exit, output, _) = AuditCommandTestHarness.Invoke(
                root, [.. args, "--url", $"http://127.0.0.1:{port}", "--username", "u", "--password", "p"]);
            await server.WaitAsync(TimeSpan.FromSeconds(5));
            return (exit, output, requestBody!);
        }
        finally
        {
            listener.Stop();
        }
    }
}