using System.IO.Compression;
using System.Security.Cryptography;
using SQLInsight.Licensing;
using SQLInsight.Rules.Lifecycle;

namespace SQLInsight.Updates.Tests;

/// <summary>A feed folder signed with a throwaway key, plus a data folder and an installation to update.</summary>
public sealed class TestFeed : IDisposable
{
    public const string KeyId = "test";

    private readonly ECDsa _key = ECDsa.Create(ECCurve.NamedCurves.nistP256);

    public TestFeed()
    {
        Root = Path.Combine(Path.GetTempPath(), "sqlinsight-updates-" + Guid.NewGuid().ToString("N"));
        Directory.CreateDirectory(FeedDirectory);
        Directories = new UpdateDirectories(Path.Combine(Root, "data"));
        Keys = new TrustedKeys([KeyValuePair.Create(KeyId, Convert.ToBase64String(_key.ExportSubjectPublicKeyInfo()))]);
        Feed = new UpdateFeed(FeedDirectory, null);
    }

    public string Root { get; }
    public string FeedDirectory => Path.Combine(Root, "feed");
    public string AgentFolder => Path.Combine(Root, "install", "Agent");
    public UpdateDirectories Directories { get; }
    public TrustedKeys Keys { get; }
    public UpdateFeed Feed { get; }

    public FileRef AddFile(string path, byte[] bytes)
    {
        var full = Path.Combine(FeedDirectory, path);
        Directory.CreateDirectory(Path.GetDirectoryName(full)!);
        File.WriteAllBytes(full, bytes);
        return new FileRef(path, Convert.ToHexString(SHA256.HashData(bytes)), bytes.Length);
    }

    public string Sign(UpdateManifest manifest) => SignedDocument.Sign(manifest, _key);

    public UpdateManifest Publish(string channel = "stable", RulePackRef? rulePack = null, AppRelease? release = null, DateTimeOffset? publishedAt = null, DateTimeOffset? expiresAt = null)
    {
        var manifest = new UpdateManifest
        {
            KeyId = KeyId,
            Channel = channel,
            PublishedAt = publishedAt ?? DateTimeOffset.UtcNow,
            ExpiresAt = expiresAt ?? DateTimeOffset.UtcNow.AddDays(30),
            RulePack = rulePack,
            Release = release,
        };
        var path = Path.Combine(FeedDirectory, channel, UpdateFeed.ManifestFile);
        Directory.CreateDirectory(Path.GetDirectoryName(path)!);
        File.WriteAllText(path, Sign(manifest));
        return manifest;
    }

    public RulePackRef RulePack(Version version)
    {
        var root = RepositoryRoot();
        var bytes = Rules.Lifecycle.RulePack.Create(version,
            File.ReadAllBytes(Path.Combine(root, "src", "SQLInsight.Rules", "Lifecycle", "build-catalog.json")),
            File.ReadAllBytes(Path.Combine(root, "src", "SQLInsight.Rules", "Lifecycle", "support-lifecycle.json")));
        return new RulePackRef(version.ToString(), AddFile($"rulepacks/rulepack-{version}.json", bytes));
    }

    /// <summary>A release whose Agent folder holds the given program file content.</summary>
    public AppRelease Release(string version, string program = "v2", string? platform = null)
    {
        using var buffer = new MemoryStream();
        using (var zip = new ZipArchive(buffer, ZipArchiveMode.Create, leaveOpen: true))
        {
            Add(zip, "Agent/SQLInsight.Agent.dll", program);
            Add(zip, "Agent/appsettings.json", "{ \"from\": \"package\" }");
            Add(zip, "Agent/runtimes/new.dll", "new");
            Add(zip, "Web/SQLInsight.Web.dll", "web");
        }

        return new AppRelease
        {
            Version = version,
            Released = new DateOnly(2026, 10, 1),
            Assets = [new ReleaseAsset(platform ?? Platform.Current, AddFile($"releases/sqlinsight-{version}.zip", buffer.ToArray()))],
        };
    }

    public void Install(string program = "v1")
    {
        Directory.CreateDirectory(AgentFolder);
        File.WriteAllText(Path.Combine(AgentFolder, "SQLInsight.Agent.dll"), program);
        File.WriteAllText(Path.Combine(AgentFolder, "appsettings.json"), "{ \"from\": \"customer\" }");
    }

    public UpdateChecker Checker(string channel = "stable") => new(Feed, Keys, Directories, channel, TimeProvider.System);

    public void Dispose()
    {
        _key.Dispose();
        if (Directory.Exists(Root))
        {
            Directory.Delete(Root, recursive: true);
        }
    }

    private static void Add(ZipArchive zip, string name, string content)
    {
        using var writer = new StreamWriter(zip.CreateEntry(name).Open());
        writer.Write(content);
    }

    private static string RepositoryRoot()
    {
        for (var dir = new DirectoryInfo(AppContext.BaseDirectory); dir is not null; dir = dir.Parent)
        {
            if (File.Exists(Path.Combine(dir.FullName, "SQLInsight.slnx")))
            {
                return dir.FullName;
            }
        }

        throw new InvalidOperationException("Repository root not found.");
    }
}

/// <summary>Services that "crash" when the installed program file says so.</summary>
public sealed class FakeServices(string programFile) : IServiceControl
{
    public List<string> Calls { get; } = [];

    public Task StopAsync(string service, CancellationToken cancellationToken)
    {
        Calls.Add("stop " + service);
        return Task.CompletedTask;
    }

    public Task StartAsync(string service, CancellationToken cancellationToken)
    {
        Calls.Add("start " + service);
        return Task.CompletedTask;
    }

    public Task<bool> IsRunningAsync(string service, CancellationToken cancellationToken) =>
        Task.FromResult(File.ReadAllText(programFile) != "broken");
}