using System.Net.Http.Json;
using ItWorx.KnowledgeHub.Contracts.Knowledge;
using ItWorx.KnowledgeHub.IntegrationTests.Infrastructure;

namespace ItWorx.KnowledgeHub.IntegrationTests.Knowledge;

/// <summary>Internal links resolve by stable page identity and survive title, slug and
/// tree changes (docs/27-acceptance-matrix.md, M2-A02).</summary>
[Collection(PostgresTestGroup.Name)]
public sealed class InternalLinkResolutionTests(PostgresContainerFixture postgres) : OwnerSetupTestBase(postgres)
{
    [Fact]
    public async Task A_resolved_internal_link_keeps_working_after_the_target_is_renamed_and_moved()
    {
        using var client = Factory.CreateClient();
        await SetupHelper.LoginAsync(client, OwnerEmail, OwnerPassword);

        var target = await CreatePageAsync(client, null, "PostgreSQL back-up herstellen");
        var newParent = await CreatePageAsync(client, null, "Nieuwe categorie");

        var sourceResponse = await SetupHelper.PostWithCsrfAsync(
            client,
            "/api/v1/pages",
            new CreatePageRequest(
                null,
                "Runbook overzicht",
                "WikiPage",
                "Zie [[PostgreSQL back-up herstellen|het herstelrunbook]] voor details.",
                null));
        var source = await sourceResponse.Content.ReadFromJsonAsync<PageDetail>();
        Assert.NotNull(source);

        Assert.Contains($"href=\"/knowledge/{target.Id}/{target.Slug}\"", source.RenderedHtml, StringComparison.Ordinal);
        Assert.Contains("het herstelrunbook", source.RenderedHtml, StringComparison.Ordinal);

        // Rename AND move the target page.
        var renamed = await SetupHelper.PutWithCsrfAsync(
            client,
            $"/api/v1/pages/{target.Id}",
            new UpdatePageRequest("PostgreSQL herstelprocedure (bijgewerkt)", target.Markdown, "Runbook", "Active", null),
            target.ETag);
        renamed.EnsureSuccessStatusCode();
        var renamedTarget = await renamed.Content.ReadFromJsonAsync<PageDetail>();
        Assert.NotNull(renamedTarget);

        var moveResponse = await SetupHelper.PostWithCsrfAndIfMatchAsync(
            client, $"/api/v1/pages/{target.Id}/move", new MovePageRequest(newParent.Id, null), renamedTarget.ETag);
        moveResponse.EnsureSuccessStatusCode();

        // Re-fetch the SOURCE page: its stored link must still resolve to the same
        // page ID even though the source page's own Markdown/authored link text was
        // never touched, and the target's title/slug/parent all changed.
        var sourceAfter = await client.GetFromJsonAsync<PageDetail>($"/api/v1/pages/{source.Id}");
        Assert.NotNull(sourceAfter);
        Assert.Contains($"/knowledge/{target.Id}/", sourceAfter.RenderedHtml, StringComparison.Ordinal);
        Assert.DoesNotContain("[[PostgreSQL", sourceAfter.RenderedHtml, StringComparison.Ordinal);
    }

    [Fact]
    public async Task An_unresolved_internal_link_target_remains_visible_as_plain_bracket_text()
    {
        using var client = Factory.CreateClient();
        await SetupHelper.LoginAsync(client, OwnerEmail, OwnerPassword);

        var response = await SetupHelper.PostWithCsrfAsync(
            client,
            "/api/v1/pages",
            new CreatePageRequest(null, "Verwijzing naar niets", "WikiPage", "Zie [[Pagina die niet bestaat]].", null));
        var page = await response.Content.ReadFromJsonAsync<PageDetail>();

        Assert.NotNull(page);
        Assert.Contains("[[Pagina die niet bestaat]]", page.RenderedHtml, StringComparison.Ordinal);
        Assert.DoesNotContain("<a ", page.RenderedHtml, StringComparison.Ordinal);
    }

    [Fact]
    public async Task An_ambiguous_internal_link_target_also_remains_unresolved_rather_than_guessing()
    {
        using var client = Factory.CreateClient();
        await SetupHelper.LoginAsync(client, OwnerEmail, OwnerPassword);

        await CreatePageAsync(client, null, "Overzicht");
        await CreatePageAsync(client, null, "Overzicht");

        var response = await SetupHelper.PostWithCsrfAsync(
            client, "/api/v1/pages", new CreatePageRequest(null, "Verwijst dubbelzinnig", "WikiPage", "Zie [[Overzicht]].", null));
        var page = await response.Content.ReadFromJsonAsync<PageDetail>();

        Assert.NotNull(page);
        Assert.Contains("[[Overzicht]]", page.RenderedHtml, StringComparison.Ordinal);
        Assert.DoesNotContain("<a ", page.RenderedHtml, StringComparison.Ordinal);
    }

    private static async Task<PageDetail> CreatePageAsync(HttpClient client, Guid? parentId, string title)
    {
        var response = await SetupHelper.PostWithCsrfAsync(
            client, "/api/v1/pages", new CreatePageRequest(parentId, title, "WikiPage", $"# {title}", null));
        response.EnsureSuccessStatusCode();
        var page = await response.Content.ReadFromJsonAsync<PageDetail>();
        Assert.NotNull(page);
        return page;
    }
}