using System.Formats.Tar;
using System.Text.Json.Nodes;

using decePubClient.E2E.Support;

using Microsoft.Playwright;

namespace decePubClient.E2E.Actions
{
	// The server's backups from Administration (owner decision 2026-10-07), as the pasture's administrator: one made now,
	// downloaded through its link (a tar whose files are the backup's), deleted and uploaded again from the browser in
	// pieces; each step checked on /clientapi
	public sealed class BackupsTests(Browser browser)
	{
		const string Root = PastureAdmin.Root;
		static readonly Pasture.Persona Admin = new("alice", "alice", Root, PastureAdmin.Password, null, null, null);

		internal static async Task<ILocator> Open(IPage page)
		{
			await page.GotoAsync($"{Pasture.Site}/administration");
			var header = page.Locator(".collapse-title", new() { HasText = "Backups" }).First;
			await header.ClickAsync();
			var panel = header.Locator("xpath=..").Locator("[data-backups]");
			await panel.Locator("[data-backup-now]").WaitForAsync(new() { Timeout = 30000 });
			return panel;
		}

		internal static async Task<string> BackUp(ILocator panel)
		{
			var before = (await PastureAdmin.Get("/clientapi/admin/backups"))!["backups"]!.AsArray().Select(b => b!["id"]!.GetValue<string>()).ToHashSet();
			await panel.Locator("[data-backup-now]").ClickAsync();
			var made = default(string);
			Assert.True(await Pasture.Eventually(async () =>
			{
				var list = (await PastureAdmin.Get("/clientapi/admin/backups"))!;
				made = list["backups"]!.AsArray().Select(b => b!["id"]!.GetValue<string>()).FirstOrDefault(id => !before.Contains(id));
				return made is not null && list["running"] is null;
			}, 300), "the backup was never made");
			await Assertions.Expect(panel.Locator($"[data-backup='{made}']")).ToBeVisibleAsync(new() { Timeout = 30000 });
			return made;
		}

		[Fact]
		public async Task A_backup_is_made_downloaded_and_uploaded_again()
		{
			await using var session = await SignIn.As(browser, Admin);
			var page = session.Page;
			var file = Path.Combine(Path.GetTempPath(), $"decepub-backup-{Guid.NewGuid():N}.tar");
			try
			{
				await Results.Cell("client.admin.backup", "privapub", Root, async () =>
				{
					var panel = await Open(page);
					var id = await BackUp(panel);
					var row = panel.Locator($"[data-backup='{id}']");
					await Assertions.Expect(row).ToContainTextAsync("Made by hand");

					// the link, for the password
					await row.Locator("[data-backup-download]").ClickAsync();
					var dialog = page.Locator("[data-backup-download-dialog]");
					await dialog.Locator("[data-backup-password]").FillAsync(PastureAdmin.Password);
					await dialog.Locator("[data-backup-confirm]").ClickAsync();
					var link = dialog.Locator("[data-backup-link]");
					await Assertions.Expect(link).ToBeVisibleAsync(new() { Timeout = 15000 });
					var download = await page.RunAndWaitForDownloadAsync(() => link.ClickAsync(), new() { Timeout = 120000 });
					await download.SaveAsAsync(file);
					var names = new List<string>();
					await using (var reader = new TarReader(File.OpenRead(file)))
						while (await reader.GetNextEntryAsync() is { } entry)
							names.Add(entry.Name);
					Assert.Contains($"{id}/manifest.json", names);
					Assert.Contains(names, n => n.StartsWith($"{id}/db/", StringComparison.Ordinal));
					await dialog.Locator("[data-backup-dialog-close]").ClickAsync();

					// deleted (asked first), then uploaded again from the file
					await row.Locator("[data-backup-delete]").ClickAsync();
					await page.Locator("[data-confirm-yes]").ClickAsync();
					await Assertions.Expect(row).ToHaveCountAsync(0, new() { Timeout = 15000 });
					Assert.DoesNotContain((await PastureAdmin.Get("/clientapi/admin/backups"))!["backups"]!.AsArray(), b => b!["id"]!.GetValue<string>() == id);

					await panel.Locator("input[data-backup-upload]").SetInputFilesAsync(file);
					await panel.Locator("[data-backup-upload-start]").ClickAsync();
					await Assertions.Expect(row).ToContainTextAsync("Uploaded", new() { Timeout = 120000 });
					var uploaded = (await PastureAdmin.Get("/clientapi/admin/backups"))!["backups"]!.AsArray().Single(b => b!["id"]!.GetValue<string>() == id)!;
					Assert.Equal("uploaded", uploaded["kind"]!.GetValue<string>());
					await session.AssertGuards();
				}, page);
			}
			finally
			{
				File.Delete(file);
			}
		}
	}

	// A real restore of the pasture from Administration: PrivaPub stops and restores as it starts again, every session
	// ends, and the page says so; signed in again, the last restore's report is there. It restores the whole server and
	// ends the town's sessions, so it runs only when asked (--filter "Category=Restore"), alone, and signs the town in
	// again (town.sh renew privapub).
	[Trait("Category", "Restore")]
	public sealed class RestoreTests(Browser browser)
	{
		static readonly Pasture.Persona Admin = new("alice", "alice", PastureAdmin.Root, PastureAdmin.Password, null, null, null);

		[Fact]
		public async Task A_backup_is_restored_and_everyone_signs_in_again()
		{
			await using var session = await SignIn.As(browser, Admin);
			var page = session.Page;
			await Results.Cell("client.admin.restore", "privapub", PastureAdmin.Root, async () =>
			{
				var panel = await BackupsTests.Open(page);
				var id = await BackupsTests.BackUp(panel);
				var host = (await PastureAdmin.Get("/clientapi/admin/backups"))!["host"]!.GetValue<string>();

				await panel.Locator($"[data-backup='{id}'] [data-backup-restore]").ClickAsync();
				var dialog = page.Locator("[data-backup-restore-dialog]");
				await dialog.Locator("[data-backup-password]").FillAsync(PastureAdmin.Password);
				var confirm = dialog.Locator("[data-backup-confirm]");
				await dialog.Locator("[data-backup-host]").FillAsync("elsewhere.test");
				await Assertions.Expect(confirm).ToBeDisabledAsync();
				await dialog.Locator("[data-backup-host]").FillAsync(host);
				await confirm.ClickAsync();
				await Assertions.Expect(page.Locator("[data-backup-restarting]")).ToBeVisibleAsync(new() { Timeout = 15000 });

				// once PrivaPub is back, the session it ended sends the page to sign in again
				await page.WaitForURLAsync(url => url.Contains("/login"), new() { Timeout = 300000 });
				await Pasture.RenewTown();
			}, page);

			await using var again = await SignIn.As(browser, Admin);
			var panelAgain = await BackupsTests.Open(again.Page);
			await Assertions.Expect(panelAgain.Locator("[data-last-restore]")).ToBeVisibleAsync(new() { Timeout = 30000 });
			Assert.NotNull((await PastureAdmin.Get("/clientapi/admin/backups"))!["lastRestore"]);
			await again.AssertGuards();
		}
	}
}