using System.Globalization;
using ZB.MOM.WW.Auth.ApiKeys.Sqlite;

namespace ZB.MOM.WW.Auth.ApiKeys.SqlServer.Tests.Live;

/// <summary>
/// Live provisioning tests for <see cref="SqlServerApiKeyStoreMigrator"/>.
/// </summary>
/// <remarks>
/// Every test provisions its own throwaway schema — the concurrency case in particular needs a
/// virgin one, because the race the retry loop exists for only happens while the schema and tables
/// do not yet exist. All schemas created by the class are dropped in <see cref="DisposeAsync"/>.
/// </remarks>
[Collection("live-sqlserver")]
public sealed class SqlServerApiKeyStoreMigratorLiveTests : IAsyncLifetime
{
    private readonly List<string> _schemas = [];

    /// <inheritdoc />
    public Task InitializeAsync() => Task.CompletedTask;

    /// <inheritdoc />
    public async Task DisposeAsync()
    {
        foreach (string schema in _schemas)
        {
            await LiveSqlServer.DropSchemaAsync(schema);
        }
    }

    private string NewSchema()
    {
        string schema = LiveSqlServer.NewSchemaName();
        _schemas.Add(schema);
        return schema;
    }

    private static SqlServerApiKeyStoreMigrator MigratorFor(string schema) =>
        new(new AuthSqlServerConnectionFactory(LiveSqlServer.OptionsFor(schema)));

    [SkippableFact]
    public async Task Migrate_OnEmptyDatabase_CreatesSchemaTablesAndVersionRow()
    {
        Skip.IfNot(LiveSqlServer.IsEnabled, LiveSqlServer.SkipReason);

        string schema = NewSchema();

        await MigratorFor(schema).MigrateAsync(CancellationToken.None);

        Assert.Equal(
            1,
            Convert.ToInt32(
                await LiveSqlServer.ScalarAsync(
                    $"SELECT COUNT(*) FROM sys.schemas WHERE name = N'{schema}'"),
                CultureInfo.InvariantCulture));

        foreach (string table in new[]
        {
            SqlServerAuthSchema.SchemaVersionTable,
            SqlServerAuthSchema.ApiKeysTable,
            SqlServerAuthSchema.ApiKeyAuditTable,
        })
        {
            Assert.NotNull(
                await LiveSqlServer.ScalarAsync($"SELECT OBJECT_ID(N'[{schema}].[{table}]', N'U')"));
        }

        Assert.Equal(
            SqlServerAuthSchema.CurrentVersion,
            Convert.ToInt32(
                await LiveSqlServer.ScalarAsync(
                    $"SELECT version FROM [{schema}].[{SqlServerAuthSchema.SchemaVersionTable}] WHERE id = 1"),
                CultureInfo.InvariantCulture));
    }

    [SkippableFact]
    public async Task Migrate_Twice_IsIdempotent()
    {
        Skip.IfNot(LiveSqlServer.IsEnabled, LiveSqlServer.SkipReason);

        string schema = NewSchema();
        SqlServerApiKeyStoreMigrator migrator = MigratorFor(schema);

        await migrator.MigrateAsync(CancellationToken.None);
        await migrator.MigrateAsync(CancellationToken.None);

        Assert.Equal(
            1,
            Convert.ToInt32(
                await LiveSqlServer.ScalarAsync(
                    $"SELECT COUNT(*) FROM [{schema}].[{SqlServerAuthSchema.SchemaVersionTable}]"),
                CultureInfo.InvariantCulture));
        Assert.Equal(
            SqlServerAuthSchema.CurrentVersion,
            Convert.ToInt32(
                await LiveSqlServer.ScalarAsync(
                    $"SELECT version FROM [{schema}].[{SqlServerAuthSchema.SchemaVersionTable}] WHERE id = 1"),
                CultureInfo.InvariantCulture));
    }

    [SkippableFact]
    public async Task Migrate_Concurrently_FromEightTasks_AllSucceed()
    {
        Skip.IfNot(LiveSqlServer.IsEnabled, LiveSqlServer.SkipReason);

        // A virgin schema provisioned by eight nodes at once — the central-pair first boot, scaled
        // up. Each task gets its own factory (and therefore its own connection) so the DDL really
        // does run on eight sessions.
        string schema = NewSchema();

        await Task.WhenAll(Enumerable.Range(0, 8).Select(_ =>
            Task.Run(() => MigratorFor(schema).MigrateAsync(CancellationToken.None))));

        Assert.Equal(
            1,
            Convert.ToInt32(
                await LiveSqlServer.ScalarAsync(
                    $"SELECT COUNT(*) FROM [{schema}].[{SqlServerAuthSchema.SchemaVersionTable}]"),
                CultureInfo.InvariantCulture));
        Assert.Equal(
            SqlServerAuthSchema.CurrentVersion,
            Convert.ToInt32(
                await LiveSqlServer.ScalarAsync(
                    $"SELECT version FROM [{schema}].[{SqlServerAuthSchema.SchemaVersionTable}] WHERE id = 1"),
                CultureInfo.InvariantCulture));
    }

    [SkippableFact]
    public async Task Migrate_WhenStoredVersionIsNewer_Throws()
    {
        Skip.IfNot(LiveSqlServer.IsEnabled, LiveSqlServer.SkipReason);

        string schema = NewSchema();
        SqlServerApiKeyStoreMigrator migrator = MigratorFor(schema);

        await migrator.MigrateAsync(CancellationToken.None);
        await LiveSqlServer.ExecuteAsync(
            $"UPDATE [{schema}].[{SqlServerAuthSchema.SchemaVersionTable}] SET version = 99 WHERE id = 1");

        AuthStoreMigrationException exception = await Assert.ThrowsAsync<AuthStoreMigrationException>(
            () => migrator.MigrateAsync(CancellationToken.None));

        Assert.Contains("99", exception.Message, StringComparison.Ordinal);
    }
}