using Microsoft.EntityFrameworkCore;
using Novelly.Api.Chapters;
using Novelly.Api.Common;
using Novelly.Api.Projects;
using Novelly.Api.Users;

namespace Novelly.Api.Tests;

[TestFixture]
public class ProjectAccessTests : ServiceTestFixture
{
    private Guid AsNewUser(GlobalRole globalRole)
    {
        var user = new NovellyUser
        {
            Id = Guid.NewGuid(),
            UserName = $"{Guid.NewGuid()}@novelly.test",
            Email = $"{Guid.NewGuid()}@novelly.test",
            DisplayName = "Test User",
            GlobalRole = globalRole
        };
        Db.Context.Users.Add(user);
        Db.Context.SaveChanges();

        UserContext.UserId = user.Id;
        UserContext.GlobalRole = globalRole;
        return user.Id;
    }

    private void GrantProjectRole(Guid projectId, Guid userId, ProjectRole role)
    {
        Db.Context.ProjectMembers.Add(new ProjectMember { ProjectId = projectId, UserId = userId, ProjectRole = role, GrantedByUserId = userId });
        Db.Context.SaveChanges();
    }

    private void AsAdmin()
    {
        UserContext.UserId = Db.Context.Users.Single(u => u.GlobalRole == GlobalRole.Admin).Id;
        UserContext.GlobalRole = GlobalRole.Admin;
    }

    [Test]
    public async Task A_writer_sees_only_novels_they_own_or_have_been_granted()
    {
        var writerId = AsNewUser(GlobalRole.Writer);
        var ownedProject = await Projects.CreateAsync(new CreateProjectRequest("Owned by writer"));

        AsAdmin();
        var otherProject = await Projects.CreateAsync(new CreateProjectRequest("Owned by someone else"));

        UserContext.UserId = writerId;
        UserContext.GlobalRole = GlobalRole.Writer;

        var visibleBeforeGrant = await Projects.ListAsync();
        Assert.That(visibleBeforeGrant.Select(p => p.Id), Is.EquivalentTo(new[] { ownedProject.Id }));

        GrantProjectRole(otherProject.Id, writerId, ProjectRole.Reviewer);

        var visibleAfterGrant = await Projects.ListAsync();
        Assert.That(visibleAfterGrant.Select(p => p.Id), Is.EquivalentTo(new[] { ownedProject.Id, otherProject.Id }));
    }

    [Test]
    public async Task An_editor_can_rewrite_a_chapter_but_cannot_delete_it()
    {
        var project = await Projects.CreateAsync(new CreateProjectRequest("Editable Novel"));
        var chapter = await Chapters.CreateAsync(project.Id, new CreateChapterRequest("Chapter One"));

        var editorId = AsNewUser(GlobalRole.Reviewer);
        GrantProjectRole(project.Id, editorId, ProjectRole.Editor);

        var updated = await Chapters.UpdateAsync(chapter!.Id, new UpdateChapterRequest(Title: "Renamed"));
        Assert.That(updated!.Title, Is.EqualTo("Renamed"));

        Assert.That(() => Chapters.DeleteAsync(chapter.Id), Throws.TypeOf<NotAuthorizedException>());
    }

    [Test]
    public void An_editor_cannot_create_a_new_novel()
    {
        AsNewUser(GlobalRole.Editor);

        Assert.That(() => Projects.CreateAsync(new CreateProjectRequest("Should not exist")), Throws.TypeOf<NotAuthorizedException>());
    }

    [Test]
    public async Task A_reviewer_can_read_a_chapter_but_not_change_it()
    {
        var project = await Projects.CreateAsync(new CreateProjectRequest("Reviewed Novel"));
        var chapter = await Chapters.CreateAsync(project.Id, new CreateChapterRequest("Chapter One"));

        var reviewerId = AsNewUser(GlobalRole.Reviewer);
        GrantProjectRole(project.Id, reviewerId, ProjectRole.Reviewer);

        var read = await Chapters.GetAsync(chapter!.Id);
        Assert.That(read, Is.Not.Null);

        Assert.That(
            () => Chapters.UpdateAsync(chapter.Id, new UpdateChapterRequest(Title: "Nope")),
            Throws.TypeOf<NotAuthorizedException>());
    }

    [Test]
    public async Task A_writer_granted_access_to_someone_elses_novel_still_cannot_grant_access_to_others()
    {
        var project = await Projects.CreateAsync(new CreateProjectRequest("Someone Else's Novel"));

        var grantedWriterId = AsNewUser(GlobalRole.Writer);
        GrantProjectRole(project.Id, grantedWriterId, ProjectRole.Writer);

        Assert.That(
            () => Access.RequireAsync(project.Id, ProjectPermission.ManageAccess),
            Throws.TypeOf<NotAuthorizedException>());
    }

    [Test]
    public async Task An_admin_reaches_every_novel()
    {
        AsNewUser(GlobalRole.Writer);
        await Projects.CreateAsync(new CreateProjectRequest("Writer's Novel"));

        AsAdmin();
        await Projects.CreateAsync(new CreateProjectRequest("Admin's Novel"));

        var visible = await Projects.ListAsync();
        Assert.That(visible, Has.Count.EqualTo(2));
    }

    [Test]
    public void Deleting_a_user_does_not_cascade_to_their_novels()
    {
        var ownerNavigation = Db.Context.Model.FindEntityType(typeof(Project))!.FindNavigation(nameof(Project.Owner))!;
        Assert.That(ownerNavigation.ForeignKey.DeleteBehavior, Is.EqualTo(DeleteBehavior.Restrict));
    }
}