/* 
 * Copyright (c) 2008 Intel Corporation
 * All rights reserved.
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * -- Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * -- Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * -- Neither the name of the Intel Corporation nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
 * PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE INTEL OR ITS
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

using System;
using System.Collections.Generic;
using System.IO;
using System.Reflection;
using ExtensionLoader;
using ExtensionLoader.Config;
using OpenMetaverse;

namespace AssetServer
{
    public class AssetServer
    {
        public const string CONFIG_FILE = "AssetServer.ini";

        public HttpServer HttpServer;
        public IniConfigSource ConfigFile;

        public IStorageProvider StorageProvider;
        public IInventoryProvider InventoryProvider;
        public IAuthenticationProvider AuthenticationProvider;
        public IAuthorizationProvider AuthorizationProvider;
        public IMetricsProvider MetricsProvider;

        public AssetServer()
        {
        }

        public bool Start()
        {
            List<string> extensionList = null;
            List<string> listenPrefixes = null;

            try { ConfigFile = new IniConfigSource(CONFIG_FILE); }
            catch (Exception)
            {
                Logger.Log.Error("Failed to load the config file " + CONFIG_FILE);
                return false;
            }

            try
            {
                IConfig extensionConfig = ConfigFile.Configs["Config"];

                // Load the addresses to listen at
                string[] prefixes = extensionConfig.GetString("ListenAddress").Split(',');
                listenPrefixes = new List<string>(prefixes.Length);
                foreach (string prefix in prefixes)
                    listenPrefixes.Add(prefix.Trim());
            }
            catch (Exception)
            {
                Logger.Log.Error("Failed to load [Config] section from " + CONFIG_FILE);
                return false;
            }

            try
            {
                // Load the extension list (and ordering) from our config file
                IConfig extensionConfig = ConfigFile.Configs["Extensions"];
                extensionList = new List<string>(extensionConfig.GetKeys());
            }
            catch (Exception)
            {
                Logger.Log.Error("Failed to load [Extensions] section from " + CONFIG_FILE);
                return false;
            }

            try
            {
                // Create a reference list for C# extensions compiled at runtime
                List<string> references = new List<string>();
                references.Add("OpenMetaverseTypes.dll");
                references.Add("OpenMetaverse.dll");
                references.Add("ExtensionLoader.dll");
                references.Add("AssetServer.exe");

                // Get a list of all of the members of AssetServer that are interfaces
                List<FieldInfo> assignables = ExtensionLoader<AssetServer>.GetInterfaces(this);

                // Load all of the extensions
                ExtensionLoader<AssetServer>.LoadAllExtensions(
                    Assembly.GetExecutingAssembly(),
                    Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location),
                    extensionList,
                    references, 
                    "AssetServer.*.dll", 
                    "AssetServer.*.cs", 
                    this, 
                    assignables);
            }
            catch (ExtensionException ex)
            {
                Logger.Log.Error("Interface loading failed, shutting down: " + ex.Message);
                if (ex.InnerException != null)
                    Logger.Log.Error(ex.InnerException.Message, ex.InnerException);
                Stop();
                return false;
            }

            try
            {
                InitHttpServer(listenPrefixes);
            }
            catch (Exception ex)
            {
                Logger.Log.Error("Initializing the HTTP server failed, shutting down: " + ex.Message);
                Stop();
                return false;
            }

            // Start all of the extensions
            foreach (IExtension<AssetServer> extension in ExtensionLoader<AssetServer>.Extensions)
            {
                Logger.Log.Info("Starting extension " + extension.GetType().Name);
                extension.Start(this);
            }

            return true;
        }

        public void Stop()
        {
            foreach (IExtension<AssetServer> extension in ExtensionLoader<AssetServer>.Extensions)
            {
                Logger.Log.Debug("Stopping extension " + extension.GetType().Name);
                try { extension.Stop(); }
                catch (Exception ex)
                { Logger.Log.ErrorFormat("Failure shutting down extension {0}: {1}", extension.GetType().Name, ex.Message); }
            }

            if (HttpServer != null)
                HttpServer.Stop();
        }

        void InitHttpServer(List<string> listenPrefixes)
        {
            HttpServer = new HttpServer(listenPrefixes);
            HttpServer.Start();

            System.Text.StringBuilder output = new System.Text.StringBuilder("Asset server is listening at: ");
            for (int i = 0; i < listenPrefixes.Count; i++)
            {
                output.Append(listenPrefixes[i]);
                if (i != listenPrefixes.Count - 1) output.Append(", ");
            }

            Logger.Log.Info(output.ToString());
        }
    }
}