using InvercargillSql.Orm.Projections;
using Invercargill.DataStructures;
using Invercargill;
using Invercargill.Expressions;

namespace Spry.Authentication {

	/**
	 * Read model over `spry_users` joined with the user's
	 * `spry_user_permissions` rows. {@link permissions} carries the user's
	 * permission patterns; {@link Spry.SpryAuth.login} copies them into the
	 * auth slot's public data.
	 */
	public class UserProjection : Object {

		public string username { get { return _username; } }
		public ImmutableLot<string> permissions { owned get { return _permissions.to_immutable_buffer(); } }

		public int64 id { get; set; }
		public string email { get; set; }
		public string forename { get; set; }
		public string surname { get; set; }
		public string password_hash { get; set; }
		public DateTime date_of_birth { get; set; }
		public DateTime created { get; set; }
		public DateTime modified { get; set; }
		public bool enabled { get; set; }

		/**
		 * SA-1/SA-14: held auth frames for this user must have been authored
		 * at or after this instant ({@link Spry.SpryAuth.revalidate}
		 * enforces it). `null` on rows written before M0002 — read it
		 * through {@link effective_sessions_valid_after}.
		 */
		public DateTime? sessions_valid_after { get; set; }

		/** {@link sessions_valid_after} with `null` resolved to the Unix epoch. */
		public DateTime effective_sessions_valid_after {
			get { return sessions_valid_after ?? UserEntity.EPOCH; }
		}

	private string _username;

	/**
	 * Starts empty (not null): a user with no joined permission rows
	 * never triggers {@link permissions}, so without this initialiser the
	 * getter would hand callers a null collection.
	 */
	private ImmutableBuffer<string> _permissions = new ImmutableBuffer<string>(new Series<string>());

		public static void projection_mapping(ProjectionBuilder<UserProjection> cfg) throws Error {
			cfg.source<UserEntity>("u")
				.select<int64?>("id", expr("u.id"), (o, v) => o.id = v)
				.select<string>("username", expr("u.username"), (o, v) => o._username = v)
				.select<string>("email", expr("u.email"), (o, v) => o.email = v)
				.select<string>("forename", expr("u.forename"), (o, v) => o.forename = v)
				.select<string>("surname", expr("u.surname"), (o, v) => o.surname = v)
				.select<string>("password_hash", expr("u.password_hash"), (o, v) => o.password_hash = v)
				.select<DateTime>("date_of_birth", expr("u.date_of_birth"), (o, v) => o.date_of_birth = v)
				.select<DateTime>("created", expr("u.created"), (o, v) => o.created = v)
				.select<DateTime>("modified", expr("u.modified"), (o, v) => o.modified = v)
				.select<bool>("enabled", expr("u.enabled"), (o, v) => o.enabled = v)
				.select<DateTime?>("sessions_valid_after", expr("u.sessions_valid_after"), (o, v) => o.sessions_valid_after = v)
				.join<UserPermissionEntity>("p", expr("p.user_id == u.id"))
				.select_many<string>("permissions", expr("p.permission"), (o, v) => o._permissions = v.to_immutable_buffer());
		}

	}

}