Add rules-aware lookup dice rolling

src/RolemasterDb.App/Data/RolemasterDbSchemaUpgrader.cs

@@ -1,3 +1,4 @@
+using System;
 using Microsoft.EntityFrameworkCore;
 
 namespace RolemasterDb.App.Data;
@@ -6,6 +7,8 @@ public static class RolemasterDbSchemaUpgrader
 {
     public static async Task EnsureLatestAsync(RolemasterDbContext dbContext, CancellationToken cancellationToken = default)
     {
+        await EnsureAttackTableFumbleColumnsAsync(dbContext, cancellationToken);
+
         await dbContext.Database.ExecuteSqlRawAsync(
             """
             CREATE TABLE IF NOT EXISTS "CriticalBranches" (
@@ -87,4 +90,65 @@ public static class RolemasterDbSchemaUpgrader
             """,
             cancellationToken);
     }
+
+    private static async Task EnsureAttackTableFumbleColumnsAsync(RolemasterDbContext dbContext, CancellationToken cancellationToken)
+    {
+        if (!await ColumnExistsAsync(dbContext, "AttackTables", "FumbleMinRoll", cancellationToken))
+        {
+            await dbContext.Database.ExecuteSqlRawAsync(
+                """
+                ALTER TABLE "AttackTables"
+                ADD COLUMN "FumbleMinRoll" INTEGER NULL;
+                """,
+                cancellationToken);
+        }
+
+        if (!await ColumnExistsAsync(dbContext, "AttackTables", "FumbleMaxRoll", cancellationToken))
+        {
+            await dbContext.Database.ExecuteSqlRawAsync(
+                """
+                ALTER TABLE "AttackTables"
+                ADD COLUMN "FumbleMaxRoll" INTEGER NULL;
+                """,
+                cancellationToken);
+        }
+    }
+
+    private static async Task<bool> ColumnExistsAsync(
+        RolemasterDbContext dbContext,
+        string tableName,
+        string columnName,
+        CancellationToken cancellationToken)
+    {
+        var connection = dbContext.Database.GetDbConnection();
+        var shouldClose = connection.State != System.Data.ConnectionState.Open;
+        if (shouldClose)
+        {
+            await connection.OpenAsync(cancellationToken);
+        }
+
+        try
+        {
+            await using var command = connection.CreateCommand();
+            command.CommandText = $"PRAGMA table_info(\"{tableName}\");";
+
+            await using var reader = await command.ExecuteReaderAsync(cancellationToken);
+            while (await reader.ReadAsync(cancellationToken))
+            {
+                if (string.Equals(reader["name"]?.ToString(), columnName, StringComparison.Ordinal))
+                {
+                    return true;
+                }
+            }
+
+            return false;
+        }
+        finally
+        {
+            if (shouldClose)
+            {
+                await connection.CloseAsync();
+            }
+        }
+    }
 }