using System.Diagnostics;
using System.Text.Json;
using System.Text.Json.Nodes;

namespace decePubClient.E2E.Support
{
	// The pasture and its town as the tests see them: the sites, the accounts the town made (read from the town's own
	// state), and the town's command line for what each server holds, so a test checks the other side of the wire.
	public static class Pasture
	{
		public const string Site = "https://decepub.test";
		public const string Api = "https://privapub.test";

		public static readonly string Root = Path.GetFullPath(Path.Combine(RepoRoot(), "..", "SocialPub", "tools", "pasture"));

		static string RepoRoot()
		{
			var dir = AppContext.BaseDirectory;
			while (dir is not null && !File.Exists(Path.Combine(dir, "decePubClient.csproj")))
				dir = Path.GetDirectoryName(dir);
			return dir ?? throw new InvalidOperationException("decePubClient.csproj not found above the test output");
		}

		public sealed record Persona(string UserName, string Name, string Root, string Password, string Token, string LocalId, string ActorUri);

		// every PrivaPub persona the town made, with its root's login
		public static IReadOnlyList<Persona> Personas()
		{
			var sessions = JsonNode.Parse(File.ReadAllText(Path.Combine(Root, ".state", "town", "sessions.json")))!.AsObject();
			var personas = new List<Persona>();
			foreach (var (key, value) in sessions)
			{
				// st_* are the drivers' selftest accounts, not the town's
				if (!key.StartsWith("privapub/") || key.StartsWith("privapub/st_") || value?["account"]?["root"]?.GetValue<string>() is not { } root)
					continue;
				var account = value["account"]!;
				personas.Add(new Persona(account["username"]!.GetValue<string>(), account["name"]?.GetValue<string>(), root,
					account["password"]!.GetValue<string>(),
					value["token"]!.GetValue<string>(), value["local_id"]!.GetValue<string>(), value["actor_uri"]!.GetValue<string>()));
			}
			return personas;
		}

		// tools/pasture/town.sh <args>, its standard output parsed as JSON
		public static async Task<JsonNode> Town(params string[] args)
		{
			var start = new ProcessStartInfo("python3") { RedirectStandardOutput = true, RedirectStandardError = true };
			start.ArgumentList.Add(Path.Combine(Root, "town", "town.py"));
			foreach (var arg in args)
				start.ArgumentList.Add(arg);
			using var process = Process.Start(start)!;
			var output = await process.StandardOutput.ReadToEndAsync();
			var error = await process.StandardError.ReadToEndAsync();
			await process.WaitForExitAsync();
			if (process.ExitCode != 0)
				throw new InvalidOperationException($"town.sh {string.Join(' ', args)} failed: {error}");
			return JsonNode.Parse(output.Trim().Split('\n').Last())!;
		}

		// what a server holds of each object, from its database (town.sh stored)
		public static async Task<JsonObject> Stored(string platform, params string[] uris) =>
			(await Town(["stored", platform, .. uris])).AsObject();

		public static async Task<bool> Eventually(Func<Task<bool>> condition, int seconds = 30)
		{
			var until = DateTime.UtcNow.AddSeconds(seconds);
			while (true)
			{
				if (await condition())
					return true;
				if (DateTime.UtcNow > until)
					return false;
				await Task.Delay(1000);
			}
		}

		public static readonly JsonSerializerOptions Json = new(JsonSerializerDefaults.Web);

		// an HttpClient that reaches https://<name>.test through Caddy on 127.0.0.1:6443, as the browser does
		public static HttpClient Http() => new(new SocketsHttpHandler
		{
			ConnectCallback = async (context, token) =>
			{
				var socket = new System.Net.Sockets.Socket(System.Net.Sockets.SocketType.Stream, System.Net.Sockets.ProtocolType.Tcp);
				await socket.ConnectAsync("127.0.0.1", 6443, token);
				return new System.Net.Sockets.NetworkStream(socket, ownsSocket: true);
			},
			SslOptions = { RemoteCertificateValidationCallback = (_, _, _, _) => true }
		});
	}
}