using System.Net;
using System.Net.Http.Json;
using System.Text.Json;
using ItWorx.KnowledgeHub.Application.Jobs;
using ItWorx.KnowledgeHub.Contracts.Jobs;
using ItWorx.KnowledgeHub.Contracts.Knowledge;
using ItWorx.KnowledgeHub.Domain.Jobs;
using ItWorx.KnowledgeHub.Infrastructure.Persistence;
using ItWorx.KnowledgeHub.IntegrationTests.Infrastructure;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.DependencyInjection;

namespace ItWorx.KnowledgeHub.IntegrationTests.Jobs;

[Collection(PostgresTestGroup.Name)]
public sealed class BackgroundJobWorkerTests(PostgresContainerFixture postgres) : OwnerSetupTestBase(postgres)
{
    [Fact]
    public async Task Worker_tags_a_database_snapshot_in_bounded_steps_and_preserves_content_metadata_and_audit()
    {
        using var client = Factory.CreateClient();
        using var login = await SetupHelper.LoginAsync(client, OwnerEmail, OwnerPassword);
        Assert.Equal(HttpStatusCode.OK, login.StatusCode);
        var rootId = await CreatePageAsync(client, null, "Course root", "root markdown", []);
        var childId = await CreatePageAsync(client, rootId, "Already tagged child", "child markdown", ["course:ccna", "KeepMe"]);
        var grandchildId = await CreatePageAsync(client, rootId, "Course grandchild", "grandchild markdown", ["existing"]);

        var csrf = await SetupHelper.GetCsrfTokenAsync(client);
        using var request = new HttpRequestMessage(HttpMethod.Post, "/api/v1/jobs/course-tagging")
        {
            Content = JsonContent.Create(new QueueCourseTaggingJobRequest(rootId, " COURSE:CCNA "))
        };
        request.Headers.Add(csrf.HeaderName, csrf.Value);
        request.Headers.Add("Idempotency-Key", "worker-course-tagging");
        using var queued = await client.SendAsync(request);
        Assert.Equal(HttpStatusCode.Accepted, queued.StatusCode);
        using var queuedJson = JsonDocument.Parse(await queued.Content.ReadAsStringAsync());
        var jobId = queuedJson.RootElement.GetProperty("id").GetGuid();

        var terminal = await WaitForTerminalAsync(client, jobId, TimeSpan.FromSeconds(30));
        Assert.Equal("succeeded", terminal.GetProperty("status").GetString());
        Assert.Equal(3, terminal.GetProperty("total").GetInt32());
        Assert.Equal(3, terminal.GetProperty("processed").GetInt32());
        Assert.Equal(2, terminal.GetProperty("succeeded").GetInt32());
        Assert.Equal(1, terminal.GetProperty("skipped").GetInt32());
        Assert.Equal(0, terminal.GetProperty("failed").GetInt32());
        Assert.Equal(100, terminal.GetProperty("progress").GetInt32());

        using var scope = Factory.Services.CreateScope();
        var db = scope.ServiceProvider.GetRequiredService<KnowledgeHubDbContext>();
        var repository = scope.ServiceProvider.GetRequiredService<ItWorx.KnowledgeHub.Application.Knowledge.IPageRepository>();
        var root = await repository.FindAsync(rootId, CancellationToken.None);
        var child = await repository.FindAsync(childId, CancellationToken.None);
        var grandchild = await repository.FindAsync(grandchildId, CancellationToken.None);
        Assert.NotNull(root);
        Assert.NotNull(child);
        Assert.NotNull(grandchild);
        Assert.Contains(root.Tags, tag => tag == "course:ccna");
        Assert.Contains(child.Tags, tag => tag == "course:ccna");
        Assert.Contains(child.Tags, tag => tag == "KeepMe");
        Assert.Contains(grandchild.Tags, tag => tag == "course:ccna");
        Assert.Equal("root markdown", root.Markdown);
        Assert.Equal("child markdown", child.Markdown);
        Assert.Equal("grandchild markdown", grandchild.Markdown);
        Assert.Equal(2, root.CurrentRevisionNumber);
        Assert.Equal(1, child.CurrentRevisionNumber);
        Assert.Equal(2, grandchild.CurrentRevisionNumber);

        var changedIds = new[] { rootId.ToString("D"), grandchildId.ToString("D") };
        Assert.Equal(2, await db.AuditEvents.AsNoTracking()
            .CountAsync(audit => audit.Action == "page.published" && changedIds.Contains(audit.TargetId)));
        Assert.Equal(2, await db.OutboxMessages.AsNoTracking()
            .CountAsync(message => message.EventType == "page.updated.v1" && changedIds.Contains(message.AggregateId)));
    }

    [Fact]
    public async Task Backup_requests_run_through_the_shared_backup_use_case_and_return_no_private_path()
    {
        using var client = Factory.CreateClient();
        using var login = await SetupHelper.LoginAsync(client, OwnerEmail, OwnerPassword);
        Assert.Equal(HttpStatusCode.OK, login.StatusCode);
        var csrf = await SetupHelper.GetCsrfTokenAsync(client);
        using var request = new HttpRequestMessage(HttpMethod.Post, "/api/v1/jobs/backups")
        {
            Content = JsonContent.Create(new QueueBackupJobRequest())
        };
        request.Headers.Add(csrf.HeaderName, csrf.Value);
        request.Headers.Add("Idempotency-Key", "worker-backup-job");
        using var queued = await client.SendAsync(request);
        Assert.Equal(HttpStatusCode.Accepted, queued.StatusCode);
        using var queuedJson = JsonDocument.Parse(await queued.Content.ReadAsStringAsync());
        var jobId = queuedJson.RootElement.GetProperty("id").GetGuid();

        var terminal = await WaitForTerminalAsync(client, jobId, TimeSpan.FromSeconds(45));
        Assert.Equal("succeeded", terminal.GetProperty("status").GetString());
        Assert.Equal(1, terminal.GetProperty("total").GetInt32());
        Assert.Equal(1, terminal.GetProperty("succeeded").GetInt32());
        var result = terminal.GetProperty("result");
        Assert.False(result.TryGetProperty("path", out _));
        Assert.False(result.TryGetProperty("directory", out _));
        Assert.False(string.IsNullOrWhiteSpace(result.GetProperty("backupId").GetString()));

        using var scope = Factory.Services.CreateScope();
        var audit = scope.ServiceProvider.GetRequiredService<KnowledgeHubDbContext>().AuditEvents;
        Assert.True(await audit.AsNoTracking().AnyAsync(item => item.Action == "backup.created"));
    }

    [Fact]
    public async Task Worker_persists_only_a_safe_bounded_error_when_backup_storage_fails_with_a_pathful_exception()
    {
        var backupPath = Factory.BackupsDirectory;
        Assert.False(Directory.Exists(backupPath));
        Assert.False(File.Exists(backupPath));
        const string privatePathMarker = "private-backup-storage-marker";
        File.WriteAllText(backupPath, privatePathMarker);

        try
        {
            using var client = Factory.CreateClient();
            using var login = await SetupHelper.LoginAsync(client, OwnerEmail, OwnerPassword);
            Assert.Equal(HttpStatusCode.OK, login.StatusCode);

            var csrf = await SetupHelper.GetCsrfTokenAsync(client);
            using var request = new HttpRequestMessage(HttpMethod.Post, "/api/v1/jobs/backups")
            {
                Content = JsonContent.Create(new QueueBackupJobRequest())
            };
            request.Headers.Add(csrf.HeaderName, csrf.Value);
            request.Headers.Add("Idempotency-Key", "backup-safe-error");
            using var queued = await client.SendAsync(request);
            Assert.Equal(HttpStatusCode.Accepted, queued.StatusCode);
            using var queuedJson = JsonDocument.Parse(await queued.Content.ReadAsStringAsync());
            var jobId = queuedJson.RootElement.GetProperty("id").GetGuid();

            var failedAttempt = await WaitForErrorsAsync(client, jobId, TimeSpan.FromSeconds(20));
            var errors = failedAttempt.GetProperty("errors");
            Assert.NotEqual(0, errors.GetArrayLength());
            Assert.Equal("processing_retry", errors[0].GetProperty("code").GetString());
            var safeMessage = errors[0].GetProperty("message").GetString();
            Assert.Equal("De tijdelijke verwerking is mislukt; de taak wordt opnieuw geprobeerd.", safeMessage);
            Assert.DoesNotContain(backupPath, safeMessage, StringComparison.OrdinalIgnoreCase);
            Assert.DoesNotContain(privatePathMarker, safeMessage, StringComparison.Ordinal);
            Assert.True(safeMessage!.Length <= BackgroundJob.MaxErrorMessageLength);

            using var cancel = await SetupHelper.PostWithCsrfAsync(
                client, $"/api/v1/jobs/{jobId:D}/cancel", new { });
            Assert.Equal(HttpStatusCode.OK, cancel.StatusCode);
            var terminal = await WaitForTerminalAsync(client, jobId, TimeSpan.FromSeconds(30));
            var terminalStatus = terminal.GetProperty("status").GetString();
            Assert.True(terminalStatus is "cancelled" or "failed");
        }
        finally
        {
            if (File.Exists(backupPath))
                File.Delete(backupPath);
        }
    }

    private static async Task<Guid> CreatePageAsync(
        HttpClient client, Guid? parentId, string title, string markdown, IReadOnlyList<string> tags)
    {
        using var response = await SetupHelper.PostWithCsrfAsync(
            client, "/api/v1/pages", new CreatePageRequest(parentId, title, "WikiPage", markdown, null, tags));
        Assert.True(response.IsSuccessStatusCode, await response.Content.ReadAsStringAsync());
        using var json = JsonDocument.Parse(await response.Content.ReadAsStringAsync());
        return json.RootElement.GetProperty("id").GetGuid();
    }

    private static async Task<JsonElement> WaitForTerminalAsync(HttpClient client, Guid jobId, TimeSpan timeout)
    {
        var stopAt = DateTimeOffset.UtcNow + timeout;
        while (DateTimeOffset.UtcNow < stopAt)
        {
            using var response = await client.GetAsync($"/api/v1/jobs/{jobId:D}");
            if (response.StatusCode == HttpStatusCode.OK)
            {
                using var json = JsonDocument.Parse(await response.Content.ReadAsStringAsync());
                var job = json.RootElement.Clone();
                if (job.GetProperty("status").GetString() is "succeeded" or "partially_succeeded" or "failed" or "cancelled")
                    return job;
            }
            await Task.Delay(100);
        }
        throw new TimeoutException($"Job {jobId:D} did not reach a terminal state within {timeout}.");
    }

    private static async Task<JsonElement> WaitForErrorsAsync(HttpClient client, Guid jobId, TimeSpan timeout)
    {
        var stopAt = DateTimeOffset.UtcNow + timeout;
        while (DateTimeOffset.UtcNow < stopAt)
        {
            using var response = await client.GetAsync($"/api/v1/jobs/{jobId:D}");
            if (response.StatusCode == HttpStatusCode.OK)
            {
                using var json = JsonDocument.Parse(await response.Content.ReadAsStringAsync());
                var job = json.RootElement.Clone();
                if (job.GetProperty("errors").GetArrayLength() > 0)
                    return job;
            }
            await Task.Delay(100);
        }
        throw new TimeoutException($"Job {jobId:D} did not persist an error within {timeout}.");
    }
}