﻿namespace Caliburn.Micro.Coroutines
{
    using System;
    using System.Collections.Generic;
    using System.ComponentModel.Composition;
    using System.ComponentModel.Composition.Hosting;
    using System.ComponentModel.Composition.Primitives;
    using System.Linq;
    using System.Windows;

    public class CoroutinesBootstrapper : BootstrapperBase
    {
        private CompositionContainer container;

        public CoroutinesBootstrapper()
        {
            Start();
        }

        protected override void Configure()
        {
            var catalog = new AggregateCatalog(AssemblySource.Instance.Select(x => new AssemblyCatalog(x)).OfType<ComposablePartCatalog>());
            container = CompositionHost.Initialize(catalog);

            var batch = new CompositionBatch();

            batch.AddExportedValue<IWindowManager>(new WindowManager());
            batch.AddExportedValue<IEventAggregator>(new EventAggregator());
            batch.AddExportedValue(container);
            batch.AddExportedValue(catalog);

            container.Compose(batch);

            Coroutine.Completed += (s, e) => {
                if (e.Error != null)
                    MessageBox.Show(e.Error.Message);
            };
        }

        protected override object GetInstance(Type serviceType, string key)
        {
            string contract = string.IsNullOrEmpty(key) ? AttributedModelServices.GetContractName(serviceType) : key;
            var exports = container.GetExportedValues<object>(contract);

            if (exports.Any())
                return exports.First();

            throw new Exception(string.Format("Could not locate any instances of contract {0}.", contract));
        }

        protected override IEnumerable<object> GetAllInstances(Type serviceType)
        {
            return container.GetExportedValues<object>(AttributedModelServices.GetContractName(serviceType));
        }

        protected override void BuildUp(object instance)
        {
            container.SatisfyImportsOnce(instance);
        }

        protected override void OnStartup(object sender, StartupEventArgs e)
        {
            DisplayRootViewFor<IShell>();
        }
    }
}
