using System.Text.Json;
using JobTrackerApi.Data;
using JobTrackerApi.Models;
using JobTrackerApi.Services;
using Microsoft.EntityFrameworkCore;
using Xunit;

namespace JobTrackerApi.MariaDb.Tests;

public sealed class DocumentsIndexTests
{
    private const string Owner = "rd21-owner";
    private const string Other = "documents-other";
    private const string PrivateContent = "PRIVATE_DOCUMENT_CONTENT";

    [Fact]
    public async Task Startup_mixed_collations_support_all_sources_counts_pagination_and_read_only_metadata()
    {
        await using var database = await MariaDbDatabase.CreateAsync();
        await SeedAsync(database);
        await using var db = database.Context();
        var collations = await db.Database.SqlQueryRaw<string>("""
            SELECT DISTINCT COLLATION_NAME AS Value FROM information_schema.COLUMNS
            WHERE TABLE_SCHEMA = DATABASE() AND
                ((TABLE_NAME = 'CvVariants' AND COLUMN_NAME = 'Name')
                OR (TABLE_NAME = 'JobApplications' AND COLUMN_NAME = 'JobTitle')
                OR (TABLE_NAME = 'Attachments' AND COLUMN_NAME = 'FileName')
                OR (TABLE_NAME = 'SubmittedApplicationPackages' AND COLUMN_NAME = 'CvVariantName')
                OR (TABLE_NAME = 'EmailDrafts' AND COLUMN_NAME = 'Subject'))
            """).ToListAsync();
        Assert.True(collations.Count > 1, "The startup-created schema must reproduce mixed source collations.");
        var before = await SnapshotAsync(database);
        var all = await GetAsync(db);
        Assert.Equal(7, all.Total);
        Assert.Equal(new[] { "application-material", "attachment", "cover-letter", "cv", "email-draft", "submitted-package", "tailored-cv" },
            all.Items.Select(item => item.Type).Order());
        var first = await GetAsync(db, pageSize: 3);
        var second = await GetAsync(db, page: 2, pageSize: 3);
        var third = await GetAsync(db, page: 3, pageSize: 3);
        Assert.Equal(7, first.Total);
        Assert.Equal(3, first.TotalPages);
        Assert.Equal(new[] { 3, 3, 1 }, new[] { first.Items.Count, second.Items.Count, third.Items.Count });
        Assert.Equal(all.Items.Select(item => item.Id), first.Items.Concat(second.Items).Concat(third.Items).Select(item => item.Id));
        var letter = Assert.Single(all.Items, item => item.Type == "cover-letter");
        Assert.Equal(1, letter.HistoryCount);
        Assert.Equal(2L, letter.Version);
        Assert.True(letter.HasCurrentContent);
        Assert.Equal("2026-01-02T00:00:00.0000000Z", letter.RecordedAt);
        Assert.Equal(1, Assert.Single(all.Items, item => item.Type == "submitted-package").AttachmentCount);
        Assert.Equal("/api/attachments/download/1", Assert.Single(all.Items, item => item.Type == "attachment").DownloadHref);
        Assert.DoesNotContain(PrivateContent, JsonSerializer.Serialize(all));
        Assert.Empty(db.ChangeTracker.Entries());
        Assert.Equal(before, await SnapshotAsync(database));
    }

    [Fact]
    public async Task Name_search_preserves_unicode_accents_literal_wildcards_and_binary_ties()
    {
        await using var database = await MariaDbDatabase.CreateAsync();
        await SeedAsync(database);
        await using var db = database.Context();
        var names = new[] { "ÆØÅ résumé", "resume", "100%", "under_score", "bang!", "decoy", "same", "same" };
        db.CvVariants.AddRange(names.Select((name, index) => Variant(10 + index, Owner, name)));
        await db.SaveChangesAsync();
        db.ChangeTracker.Clear();
        foreach (var (query, expected) in new[] { ("æøå", "cv:10"), ("RÉSUMÉ", "cv:10"), ("resume", "cv:11"), ("%", "cv:12"), ("_", "cv:13"), ("!", "cv:14") })
        {
            var result = await GetAsync(db, q: query, type: "cv", pageSize: 1);
            Assert.Equal(1, result.Total);
            Assert.Equal(expected, Assert.Single(result.Items).Id);
        }
        var ties = await GetAsync(db, q: "same", type: "cv");
        Assert.Equal(new[] { "cv:16", "cv:17" }, ties.Items.Select(item => item.Id));
        Assert.Empty((await GetAsync(db, q: PrivateContent)).Items);
        Assert.Empty(db.ChangeTracker.Entries());
    }

    [Fact]
    public async Task Tenant_joins_and_filters_exclude_foreign_documents_and_damaged_associations()
    {
        await using var database = await MariaDbDatabase.CreateAsync();
        await SeedAsync(database);
        await using var db = database.Context();
        var damaged = Variant(3, Owner, "Damaged association");
        damaged.JobApplicationId = 2;
        db.CvVariants.Add(damaged);
        db.EmailDrafts.Add(Draft(Owner, 2, "Foreign linked draft"));
        db.SubmittedApplicationPackages.Add(new() { OwnerUserId = Owner, JobApplicationId = 2, Version = 99, CvVariantName = "Foreign linked package" });
        db.CoverLetterVersions.Add(new() { OwnerUserId = Other, JobApplicationId = 1, Version = 99, Text = PrivateContent });
        await db.SaveChangesAsync();
        db.ChangeTracker.Clear();
        var before = await SnapshotAsync(database);
        var own = await GetAsync(db);
        Assert.Equal(8, own.Total);
        Assert.DoesNotContain(own.Items, item => item.Name.StartsWith("Foreign", StringComparison.Ordinal));
        Assert.DoesNotContain(own.Items, item => item.CompanyName == "Foreign company");
        var orphan = Assert.Single(own.Items, item => item.Id == "cv:3");
        Assert.Null(orphan.JobApplicationId);
        Assert.Null(orphan.CompanyName);
        Assert.Null(orphan.JobTitle);
        Assert.Equal(1, Assert.Single(own.Items, item => item.Type == "cover-letter").HistoryCount);
        Assert.Empty((await GetAsync(db, job: 2)).Items);
        Assert.Equal(7, (await GetAsync(db, job: 1)).Total);
        Assert.Equal(1, (await GetAsync(db, type: "cv", visibility: "public")).Total);
        Assert.Equal(4, (await GetAsync(db, state: "draft")).Total);
        var foreign = await GetAsync(db, owner: Other);
        Assert.Equal(7, foreign.Total);
        Assert.All(foreign.Items, item => Assert.Equal(2, item.JobApplicationId));
        Assert.Empty(db.ChangeTracker.Entries());
        Assert.Equal(before, await SnapshotAsync(database));
    }

    private static Task<DocumentsPageDto> GetAsync(JobTrackerContext db, int page = 1, int pageSize = 100,
        string? q = null, string type = "all", string state = "all", string visibility = "all", int? job = null, string owner = Owner)
        => new DocumentsIndexService(db).GetAsync(owner, page, pageSize, q, type, state, visibility, job, "name-asc", default);

    private static CvVariant Variant(int id, string owner, string name) => new()
    {
        Id = id, OwnerUserId = owner, Name = name, PublicSlug = $"documents-{id}", SettingsJson = PrivateContent,
        Version = 1, CreatedAtUtc = DateTimeOffset.Parse("2026-01-01T00:00:00Z"), UpdatedAtUtc = DateTimeOffset.Parse("2026-01-01T00:00:00Z"),
    };

    private static EmailDraft Draft(string owner, int job, string subject) => new()
    {
        Id = Guid.NewGuid(), OwnerUserId = owner, JobApplicationId = job, Subject = subject, Provider = "gmail",
        To = "private@example.test", BodyText = PrivateContent, ClientRequestId = Guid.NewGuid().ToString(),
        CreatedAtUtc = new DateTime(2026, 1, 1), UpdatedAtUtc = new DateTime(2026, 1, 1),
    };

    private static async Task SeedAsync(MariaDbDatabase database)
    {
        await using var db = database.Context();
        foreach (var (id, owner) in new[] { (1, Owner), (2, Other) })
        {
            db.Users.Add(new() { Id = owner, UserName = owner });
            db.Companies.Add(new() { Id = id, OwnerUserId = owner, Name = id == 1 ? "Nordlys" : "Foreign company" });
            db.JobApplications.Add(new()
            {
                Id = id, OwnerUserId = owner, CompanyId = id, JobTitle = id == 1 ? "Owned role" : "Foreign role",
                CoverLetterText = PrivateContent, TailoredCvText = PrivateContent, RecruiterMessageDraft = PrivateContent,
            });
            var cv = Variant(id, owner, id == 1 ? "Public CV" : "Foreign CV");
            cv.JobApplicationId = id;
            cv.IsPublic = true;
            db.CvVariants.Add(cv);
            db.CoverLetterVersions.Add(new() { OwnerUserId = owner, JobApplicationId = id, Version = 2, Text = PrivateContent, CreatedAtUtc = DateTimeOffset.Parse("2026-01-02T00:00:00Z") });
            db.Attachments.Add(new() { Id = id, JobApplicationId = id, FileName = "Portfolio.pdf", FilePath = PrivateContent, FileType = "application/pdf", FileSize = 41, UploadDate = new DateTime(2026, 1, 1) });
            db.SubmittedApplicationPackages.Add(new()
            {
                OwnerUserId = owner, JobApplicationId = id, Version = 1, CvVariantName = "Captured CV", CoverLetterText = PrivateContent,
                Attachments = [new() { FileName = "Captured.pdf", FilePath = PrivateContent, FileType = "application/pdf", Sha256 = new string('a', 64) }],
            });
            db.EmailDrafts.Add(Draft(owner, id, "Saved subject"));
        }
        await db.SaveChangesAsync();
    }

    private static async Task<string> SnapshotAsync(MariaDbDatabase database)
    {
        await using var db = database.Context();
        return JsonSerializer.Serialize(new
        {
            Jobs = await db.JobApplications.IgnoreQueryFilters().AsNoTracking().OrderBy(x => x.Id).ToListAsync(),
            Variants = await db.CvVariants.IgnoreQueryFilters().AsNoTracking().OrderBy(x => x.Id).ToListAsync(),
            Letters = await db.CoverLetterVersions.IgnoreQueryFilters().AsNoTracking().OrderBy(x => x.Id).ToListAsync(),
            Attachments = await db.Attachments.IgnoreQueryFilters().AsNoTracking().OrderBy(x => x.Id).ToListAsync(),
            Packages = await db.SubmittedApplicationPackages.IgnoreQueryFilters().AsNoTracking().OrderBy(x => x.Id).ToListAsync(),
            Archived = await db.SubmittedPackageAttachments.IgnoreQueryFilters().AsNoTracking().OrderBy(x => x.Id).ToListAsync(),
            Drafts = await db.EmailDrafts.IgnoreQueryFilters().AsNoTracking().OrderBy(x => x.Id).ToListAsync(),
        });
    }
}