Working on this data setup logic

Database/IdentitySystem/Setup.cs

@@ -0,0 +1,115 @@
+using System;
+using System.Data;
+using System.Threading.Tasks;
+
+namespace Database.Tenants
+{
+    public class DbSetup
+    {
+        private readonly IDbConnection _db;
+
+        public DbSetup(IDbConnection db)
+        {
+            _db = db ?? throw new ArgumentNullException(nameof(db));
+        }
+
+        /// <summary>
+        /// Creates the users table in the ptmain schema.
+        /// </summary>
+        public void CreateUsersTable()
+        {
+            ExecuteInTransaction(@"
+                CREATE TABLE IF NOT EXISTS ptmain.users (
+                    id SERIAL PRIMARY KEY,
+                    email VARCHAR(256) NOT NULL UNIQUE,
+                    password_hash VARCHAR(256) NOT NULL,
+                    security_stamp VARCHAR(36) NOT NULL,
+                    email_confirmed BOOLEAN NOT NULL DEFAULT FALSE,
+                    access_failed_count INTEGER NOT NULL DEFAULT 0,
+                    lockout_enabled BOOLEAN NOT NULL DEFAULT TRUE,
+                    lockout_end TIMESTAMPTZ NULL,
+                    is_active BOOLEAN NOT NULL DEFAULT TRUE,
+                    created_at TIMESTAMPTZ NOT NULL DEFAULT CURRENT_TIMESTAMP,
+                    last_login_at TIMESTAMPTZ NULL
+                );");
+        }
+
+        /// <summary>
+        /// Creates the tenants table in the ptmain schema.
+        /// </summary>
+        public void CreateTenantsTable()
+        {
+            ExecuteInTransaction(@"
+                CREATE TABLE IF NOT EXISTS ptmain.tenants (
+                    id SERIAL PRIMARY KEY,
+                    connection_string VARCHAR(500) NOT NULL,
+                    is_active BOOLEAN NOT NULL DEFAULT TRUE,
+                    created_by INTEGER NOT NULL REFERENCES ptmain.users(id),
+                    created_at TIMESTAMPTZ NOT NULL DEFAULT CURRENT_TIMESTAMP
+                );");
+        }
+
+        /// <summary>
+        /// Creates the user_tenants table in the ptmain schema.
+        /// </summary>
+        public void CreateUserTenantsTable()
+        {
+            ExecuteInTransaction(@"
+                CREATE TABLE IF NOT EXISTS ptmain.user_tenants (
+                    user_id INTEGER NOT NULL REFERENCES ptmain.users(id),
+                    tenant_id INTEGER NOT NULL REFERENCES ptmain.tenants(id),
+                    pin_code VARCHAR(10) NULL,
+                    created_at TIMESTAMPTZ NOT NULL DEFAULT CURRENT_TIMESTAMP,
+                    PRIMARY KEY (user_id, tenant_id)
+                );");
+        }
+
+        /// <summary>
+        /// Sets up Row Level Security (RLS) for the tenants and user_tenants tables.
+        /// </summary>
+        public void SetupRLS()
+        {
+            ExecuteInTransaction(
+                "ALTER TABLE ptmain.tenants ENABLE ROW LEVEL SECURITY;",
+                "ALTER TABLE ptmain.user_tenants ENABLE ROW LEVEL SECURITY;",
+                "DROP POLICY IF EXISTS tenant_access ON ptmain.tenants;",
+                @"
+                CREATE POLICY tenant_access ON ptmain.tenants
+                    USING (id IN (
+                        SELECT tenant_id 
+                        FROM ptmain.user_tenants 
+                        WHERE user_id = current_setting('app.user_id', TRUE)::INTEGER
+                    ));",
+                "DROP POLICY IF EXISTS user_tenant_access ON ptmain.user_tenants;",
+                @"
+                CREATE POLICY user_tenant_access ON ptmain.user_tenants
+                    USING (user_id = current_setting('app.user_id', TRUE)::INTEGER);"
+            );
+        }
+
+        /// <summary>
+        /// Executes one or more SQL commands within a transaction.
+        /// </summary>
+        /// <param name="sqlCommands">The SQL commands to execute.</param>
+        private void ExecuteInTransaction(params string[] sqlCommands)
+        {
+            if (_db.State != ConnectionState.Open)
+                _db.Open();
+
+            using var transaction = _db.BeginTransaction();
+            try
+            {
+                foreach (var sql in sqlCommands)
+                {
+                    _db.ExecuteSql(sql, transaction: transaction);
+                }
+                transaction.Commit();
+            }
+            catch (Exception ex)
+            {
+                transaction.Rollback();
+                throw new InvalidOperationException("Failed to execute SQL commands in transaction.", ex);
+            }
+        }
+    }
+}