using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Client.Framework;
using NHibernate;

namespace Example.Specs.Creators
{
    // Creator<T> provides an framework for defining streamlined, *test-only* factories for domain entities..
    // it mostly provides needed infrastructure that a test harness can hook into to make it possible to
    // create and persist Nhib entities in a test environment.
    public class Creator<T>
    {
        // the only thing worth knowing about ISessionProvider is that it wraps an NHib ISession
        ISessionProvider _sessionProvider;
        // This represents the various databases that the client has
        DatabaseName _db;

        // we keep an instance of the FluentFixtures ourselves as a member here so that a Creator
        // has access to New, the same as the test code shown in fluent_fixtures_example.cs
        FluentFixtures _fixtures;
        public FluentFixtures New { get { return _fixtures; } }

        public Creator(ISessionProvider sessionProvider, DatabaseName db,FluentFixtures fixtures)
        {
            _sessionProvider = sessionProvider;
            _db = db;
            _fixtures = fixtures;
        }

        public void Flush()
        {
            Session.Flush();
        }

        public void Evict()
        {
            Session.Evict(Creation);
        }

        public void Save()
        {
            Session.Save(Creation);
            // we're flushing left-and-right for convenience.. not performant at all and
            // obviously not aprop. for production use.
            Flush();
        }

        public K SimpleChange<K>(Action<T> input) where K: Creator<T>
        {
            input(Creation);
            Save();
            return (K)this;
        }

        public T Creation { get; set; }

        public ISession Session { get { return _sessionProvider.CurrentSessionOn(_db); } }

        public static implicit operator T (Creator<T> input)
        {
            return input.Creation;
        }
    }
}