using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Mvc.Testing;
using Microsoft.Data.SqlClient;
using SQLInsight.Collectors.Instance;
using SQLInsight.Core.Data;
using SQLInsight.Core.Instances;
using SQLInsight.Repository;

namespace SQLInsight.IntegrationTests;

/// <summary>tempdb and the version store as the least-privilege agent reads them.</summary>
[Collection(SqlServerTestGroup.Name)]
[Trait("Category", "Integration")]
public class TempdbTests(SqlServerFixture sql)
{
    [Fact]
    public async Task Space_version_store_and_the_session_filling_tempdb_are_read()
    {
        await using var user = new SqlConnection(new SqlConnectionStringBuilder(sql.SaConnectionString) { ApplicationName = "Rapport" }.ConnectionString);
        await user.OpenAsync();
        await using (var fill = new SqlCommand("CREATE TABLE #big (Id int, Pad char(4000)); INSERT #big SELECT TOP (3000) 1, 'x' FROM sys.all_objects a CROSS JOIN sys.all_objects b;", user))
        {
            await fill.ExecuteNonQueryAsync();
        }

        await using var session = await AgentSession.OpenAsync(sql);
        var first = await session.CollectAsync<TempdbSnapshot>(new TempdbCollector(sessionMegabytes: 1));
        var second = await session.CollectAsync(new TempdbCollector(sessionMegabytes: 1), first);

        Assert.True(first.SizeMegabytes > 0);
        Assert.InRange(first.FreeMegabytes, 0, first.SizeMegabytes);
        Assert.True(first.VersionStoreMegabytes >= 0);
        var heavy = Assert.Single(first.TopSessions, s => s.ProgramName == "Rapport");
        Assert.True(heavy.UsedMegabytes >= 10);
        Assert.Equal(2, second.VersionStoreHistory.Count);
        Assert.Equal(first.HeavySessionsSince[heavy.Key], second.HeavySessionsSince[heavy.Key]); // the start is kept
    }

    [Fact]
    public async Task Instance_page_and_api_show_tempdb_with_logins_left_out()
    {
        var database = "SQLInsightTmp_" + Guid.NewGuid().ToString("N")[..8];
        await sql.ExecuteAsSaAsync($"CREATE DATABASE [{database}];");
        try
        {
            var repository = new InsightRepository(sql.DatabaseConnectionString(database));
            await repository.MigrateAsync();
            var now = DateTimeOffset.UtcNow;
            var id = await repository.UpsertInstanceAsync("prod-sql01", new InstanceInfo
            {
                ServerName = "SQL01", Version = SqlServerVersion.Parse("16.0.4135.4"), ProductLevel = "RTM", Edition = "Standard Edition", EngineEdition = EngineEdition.Standard,
            }, "SqlClient", false, now);
            await repository.SaveCollectedAsync(id, "tempdb", new TempdbSnapshot
            {
                CapturedAt = now, SizeMegabytes = 8192, FreeMegabytes = 1024, VersionStoreMegabytes = 2048,
                TopSessions = [new TempdbSession(70, now.AddHours(-1), 3000, @"KUNDE\anne", "SSMS", "PC01", "running")],
                VersionGenerators = [new VersionGenerator("AXDB", 1800)],
            });

            await using var factory = new WebApplicationFactory<Program>().WithWebHostBuilder(b =>
            {
                b.UseEnvironment("Development");
                b.UseSetting("SQLInsight:Repository:ConnectionString", sql.DatabaseConnectionString(database));
                b.UseSetting("SQLInsight:Web:Authentication", "None");
            });
            var client = factory.CreateClient();
            var page = await client.GetStringAsync("/instanser/prod-sql01");
            var api = await client.GetStringAsync("/api/v1/instances/prod-sql01/tempdb");

            Assert.Contains("tempdb lige nu", page, StringComparison.Ordinal);
            Assert.Contains("AXDB", page, StringComparison.Ordinal);
            Assert.Contains("Version store (MB)", page, StringComparison.Ordinal); // the graph with its explanation
            Assert.Contains("\"versionStoreMegabytes\":2048", api, StringComparison.Ordinal);
            Assert.DoesNotContain("anne", api, StringComparison.Ordinal);
            Assert.Single(await repository.GetMetricSamplesAsync(id, Metrics.VersionStoreMegabytes, now.AddMinutes(-5), now.AddMinutes(5)));
        }
        finally
        {
            await sql.ExecuteAsSaAsync($"ALTER DATABASE [{database}] SET SINGLE_USER WITH ROLLBACK IMMEDIATE; DROP DATABASE [{database}];");
        }
    }
}