using Microsoft.EntityFrameworkCore.Migrations;

#nullable disable

namespace ZB.MOM.WW.ScadaBridge.ConfigurationDatabase.Migrations
{
    /// <summary>Review-remediation composite indexes on AuditLog (partition-aligned, raw SQL) and AuditLogEntries.</summary>
    public partial class ReviewRemediationIndexes : Migration
    {
        /// <inheritdoc />
        protected override void Up(MigrationBuilder migrationBuilder)
        {
            migrationBuilder.CreateIndex(
                name: "IX_AuditLogEntries_EntityType_Timestamp",
                table: "AuditLogEntries",
                columns: new[] { "EntityType", "Timestamp" },
                descending: new[] { false, true });

            migrationBuilder.CreateIndex(
                name: "IX_AuditLogEntries_Timestamp_Id",
                table: "AuditLogEntries",
                columns: new[] { "Timestamp", "Id" },
                descending: new bool[0]);

            migrationBuilder.CreateIndex(
                name: "IX_AuditLogEntries_User_Timestamp",
                table: "AuditLogEntries",
                columns: new[] { "User", "Timestamp" },
                descending: new[] { false, true });

            // AuditLog is monthly-partitioned (ps_AuditLog_Month) with a partition-switch
            // purge, so these two indexes MUST be partition-aligned. EF's CreateIndex cannot
            // express the ON ps_AuditLog_Month(OccurredAtUtc) clause -> raw SQL, exactly as
            // IX_AuditLog_Node_Occurred (AddAuditLogSourceNode). Kind is a PERSISTED computed
            // column, so it is indexable. On a large production AuditLog consider adding
            // WITH (ONLINE = ON) (Enterprise edition) to the generated script.
            migrationBuilder.Sql(@"
CREATE NONCLUSTERED INDEX IX_AuditLog_Kind_Occurred
ON dbo.AuditLog (Kind, OccurredAtUtc DESC)
ON ps_AuditLog_Month(OccurredAtUtc);");

            migrationBuilder.Sql(@"
CREATE NONCLUSTERED INDEX IX_AuditLog_Actor_Occurred
ON dbo.AuditLog (Actor, OccurredAtUtc DESC)
ON ps_AuditLog_Month(OccurredAtUtc);");
        }

        /// <inheritdoc />
        protected override void Down(MigrationBuilder migrationBuilder)
        {
            migrationBuilder.DropIndex(
                name: "IX_AuditLogEntries_EntityType_Timestamp",
                table: "AuditLogEntries");

            migrationBuilder.DropIndex(
                name: "IX_AuditLogEntries_Timestamp_Id",
                table: "AuditLogEntries");

            migrationBuilder.DropIndex(
                name: "IX_AuditLogEntries_User_Timestamp",
                table: "AuditLogEntries");

            migrationBuilder.Sql(@"
IF EXISTS (SELECT 1 FROM sys.indexes WHERE name = 'IX_AuditLog_Actor_Occurred' AND object_id = OBJECT_ID('dbo.AuditLog'))
    DROP INDEX IX_AuditLog_Actor_Occurred ON dbo.AuditLog;");

            migrationBuilder.Sql(@"
IF EXISTS (SELECT 1 FROM sys.indexes WHERE name = 'IX_AuditLog_Kind_Occurred' AND object_id = OBJECT_ID('dbo.AuditLog'))
    DROP INDEX IX_AuditLog_Kind_Occurred ON dbo.AuditLog;");
        }
    }
}