using JobTrackerApi.Data;
using JobTrackerApi.Models;
using JobTrackerApi.Services;
using Microsoft.Data.Sqlite;
using Microsoft.EntityFrameworkCore;
using Moq;
using Xunit;

namespace JobTrackerApi.Tests;

public sealed class CvRevisionReadinessTests
{
    private static JobTrackerContext Context(SqliteConnection connection, string owner = "revision-owner")
    {
        var principal = new Mock<ICurrentUserService>();
        principal.SetupGet(x => x.UserId).Returns(owner);
        return new JobTrackerContext(new DbContextOptionsBuilder<JobTrackerContext>().UseSqlite(connection).Options, principal.Object);
    }

    private static CvVariantService Service(JobTrackerContext db) => new(db, new CareerProfileService(db), new ThemedCvRenderer());

    [Theory]
    [InlineData(false)]
    [InlineData(true)]
    public async Task Independent_stale_save_or_restore_cannot_replace_the_newer_revision(bool restore)
    {
        await using var connection = new SqliteConnection("Data Source=:memory:");
        await connection.OpenAsync();
        await using var first = Context(connection);
        await first.Database.EnsureCreatedAsync();
        var a = Service(first);
        var cv = await a.CreateAsync("revision-owner", "Revision fixture", null, new CvVariantSettings { Headline = "Original" }, default);
        await using var second = Context(connection);
        var b = Service(second);
        Assert.Equal(1, (await b.GetAsync("revision-owner", cv.Id, default))!.Version);

        await a.SaveAsync("revision-owner", cv.Id, null, new CvVariantSettings { Headline = "Newer reviewed content" }, "manual", 1, default);
        await Assert.ThrowsAsync<DbUpdateConcurrencyException>(() => restore
            ? b.RestoreVersionAsync("revision-owner", cv.Id, 1, 1, default)
            : b.SaveAsync("revision-owner", cv.Id, null, new CvVariantSettings { Headline = "Stale draft" }, "autosave", 1, default));

        await using var verify = Context(connection);
        var saved = await verify.CvVariants.SingleAsync();
        Assert.Equal(2, saved.Version);
        Assert.Equal("Newer reviewed content", CvVariantSettingsJson.Deserialize(saved.SettingsJson).Headline);
        var history = await verify.CvVariantVersions.OrderBy(x => x.Version).ToListAsync();
        Assert.Equal(new[] { 1, 2 }, history.Select(x => x.Version));
        Assert.Equal("Original", CvVariantSettingsJson.Deserialize(history[0].SettingsJson).Headline);
    }

    [Fact]
    public async Task Fresh_request_with_a_stale_expected_version_is_rejected_before_appending_history()
    {
        await using var connection = new SqliteConnection("Data Source=:memory:");
        await connection.OpenAsync();
        await using var first = Context(connection);
        await first.Database.EnsureCreatedAsync();
        var service = Service(first);
        var cv = await service.CreateAsync("revision-owner", "CV", null, null, default);
        await service.SaveAsync("revision-owner", cv.Id, null, new CvVariantSettings { Headline = "Winner" }, "manual", 1, default);
        await using var fresh = Context(connection);
        await Assert.ThrowsAsync<DbUpdateConcurrencyException>(() => Service(fresh).SaveAsync("revision-owner", cv.Id, "Stale rename", new CvVariantSettings(), "autosave", 1, default));
        Assert.Equal(2, await fresh.CvVariantVersions.CountAsync());
        Assert.Equal("CV", (await fresh.CvVariants.SingleAsync()).Name);
    }

    [Fact]
    public async Task Settings_history_restore_and_override_reset_preserve_the_canonical_source_contract()
    {
        await using var connection = new SqliteConnection("Data Source=:memory:");
        await connection.OpenAsync();
        await using var db = Context(connection);
        await db.Database.EnsureCreatedAsync();
        var career = new CareerProfileService(db);
        var profile = new StructuredCvProfile
        {
            Contact = new() { FullName = "Åse Fixture", Headline = "Canonical source" },
            Jobs = { new() { Id = "source-entry", Title = "Canonical role", Company = "Nordlys", Bullets = { "Canonical evidence" } } },
            Skills = { "C#", "Norsk" },
        };
        await career.SaveVersionAsync("revision-owner", profile, "manual", default);
        var service = Service(db);
        var lens = new CvVariantSettings
        {
            Headline = "CV-only headline", ThemeId = "code", PageMarginMm = 28, Density = "compact",
            Sections = { new() { Key = "skills", Hidden = true }, new() { Key = "experience" }, new() { Key = "summary" } },
            Overrides = { ["source-entry"] = new() { Title = "CV-only role", Bullets = new() { "Reviewed override" } } },
        };
        var cv = await service.CreateAsync("revision-owner", "Variant", null, lens, default);
        var originalHistory = (await db.CvVariantVersions.SingleAsync()).SettingsJson;
        Assert.Equal("Canonical role", (await career.LoadStructuredAsync("revision-owner", default)).Jobs[0].Title);
        var rendered = await service.RenderAsync("revision-owner", cv.Id, new("Fallback", null), default);
        Assert.Contains("CV-only role", rendered!.Html);
        Assert.DoesNotContain("Canonical evidence", rendered.Html);
        Assert.DoesNotContain("section-skills", rendered.Html);

        // History is the immutable lens; inherited source values intentionally remain live.
        profile.Contact.Headline = "Updated canonical source";
        profile.Jobs[0].Title = "Updated canonical role";
        await career.SaveVersionAsync("revision-owner", profile, "manual", default);
        Assert.Equal(originalHistory, (await db.CvVariantVersions.SingleAsync()).SettingsJson);
        var reset = new CvVariantSettings { ThemeId = "minimal" };
        await service.SaveAsync("revision-owner", cv.Id, null, reset, "manual", 1, default);
        rendered = await service.RenderAsync("revision-owner", cv.Id, new("Fallback", null), default);
        Assert.Contains("Updated canonical role", rendered!.Html);
        Assert.Contains("Updated canonical source", rendered.Html);

        var restored = await service.RestoreVersionAsync("revision-owner", cv.Id, 1, 2, default);
        Assert.Equal(3, restored!.Version);
        Assert.Equal(originalHistory, restored.SettingsJson);
        await service.SaveAsync("revision-owner", cv.Id, null, new CvVariantSettings { Headline = "After restore" }, "autosave", 3, default);
        Assert.Equal(originalHistory, (await db.CvVariantVersions.SingleAsync(x => x.Version == 1)).SettingsJson);
        Assert.Equal(originalHistory, (await db.CvVariantVersions.SingleAsync(x => x.Version == 3)).SettingsJson);
        Assert.Equal(new[] { 4, 3, 2, 1 }, (await service.ListVersionsAsync("revision-owner", cv.Id, default)).Select(x => x.Version));
        Assert.Equal("Updated canonical role", (await career.LoadStructuredAsync("revision-owner", default)).Jobs[0].Title);
    }

    [Fact]
    public async Task Foreign_account_cannot_read_save_or_restore_revision_history()
    {
        await using var connection = new SqliteConnection("Data Source=:memory:");
        await connection.OpenAsync();
        await using var owner = Context(connection);
        await owner.Database.EnsureCreatedAsync();
        var cv = await Service(owner).CreateAsync("revision-owner", "Private", null, null, default);
        await using var other = Context(connection, "other-account");
        var service = Service(other);
        Assert.Null(await service.GetAsync("other-account", cv.Id, default));
        Assert.Empty(await service.ListVersionsAsync("other-account", cv.Id, default));
        Assert.Null(await service.SaveAsync("other-account", cv.Id, "Overwrite", new(), "manual", 1, default));
        Assert.Null(await service.RestoreVersionAsync("other-account", cv.Id, 1, 1, default));
        Assert.Single(await owner.CvVariantVersions.ToListAsync());
    }
}