Combres - WebForm & MVC Client-side Resource Combine Library

#region License
// Copyright 2009 Buu Nguyen (http://www.buunguyen.net/blog)
// 
// Licensed under the Apache License, Version 2.0 (the "License"); 
// you may not use this file except in compliance with the License. 
// You may obtain a copy of the License at 
// 
// http://www.apache.org/licenses/LICENSE-2.0 
// 
// Unless required by applicable law or agreed to in writing, software 
// distributed under the License is distributed on an "AS IS" BASIS, 
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
// See the License for the specific language governing permissions and 
// limitations under the License.
// 
// The latest version of this file can be found at http://combres.codeplex.com
#endregion

using System;
using System.Collections;
using System.Collections.Generic;
using System.Xml;
using System.Xml.Schema;

namespace Combres
{
    /// <summary>
    /// Represents a group of resource files.
    /// </summary>
    public class ResourceSet : IEnumerable<Resource>
    {
        /// <summary>
        /// The name of the resource group.  This is to be referred to when generating
        /// links or URLs to the group.
        /// </summary>
        public string Name { get; private set; }

        /// <summary>
        /// Version of this resource group.
        /// </summary>
        public string Version { get; private set; }

        /// <summary>
        /// Duration of this resource group.  Specify how long the generated result
        /// should be cached at both client and server.
        /// </summary>
        public TimeSpan DurationInDays { get; private set; }

        /// <summary>
        /// The type of resource (JavaScript or CSS).
        /// </summary>
        public ResourceType Type { get; private set; }

        /// <summary>
        /// If true, items in this resource set won't be cached, compressed and minimized 
        /// to facilitate debugging.
        /// </summary>
        public bool DebugEnabled { get; private set; }

        /// <summary>
        /// The child resources.
        /// </summary>
        private List<Resource> resources = new List<Resource>();

        /// <summary>
        /// List of child resources.
        /// </summary>
        public List<Resource> Resources { get { return resources;} }

        internal ResourceSet(Settings parent, XmlElement section)
        {
            Name = section.GetAttribute(NodeConstants.SetName);
            InitializeDuration(section, parent);
            InitializeVersion(section, parent);
            InitializeCategory(section);
            InitializeDebugEnabled(section, parent);
            foreach (var node in section.ChildNodes)
            {
                if (node is XmlElement)
                {
                    resources.Add(new Resource(node as XmlElement, this));
                }
            }
        }

        private void InitializeVersion(XmlElement section, Settings parent)
        {
            var version = section.GetAttribute(NodeConstants.SetVersion);
            if (string.IsNullOrEmpty(version))
            {
                if (parent.DefaultVersion == null)
                    throw new XmlSchemaException(NodeConstants.SettingDefaultVersion + " must be available if not specified in resourceSet");
                Version = parent.DefaultVersion;
            }
            else
            {
                Version = version;
            }
        }

        private void InitializeDuration(XmlElement section, Settings parent)
        {
            var duration = section.GetAttribute(NodeConstants.SetDuration);
            if (string.IsNullOrEmpty(duration))
            {
                if (parent.DefaultDuration == null)
                    throw new XmlSchemaException(NodeConstants.SettingDefaultDuration + " must be available if not specified in resourceSet");
                DurationInDays = TimeSpan.FromDays(parent.DefaultDuration.Value);
            }
            else
            {
                DurationInDays = TimeSpan.FromDays(int.Parse(duration));
            }
        }

        private void InitializeCategory(XmlElement section)
        {
            Type = (ResourceType)Enum.Parse(typeof(ResourceType),
                                        section.GetAttribute(NodeConstants.SetType).ToUpperInvariant());
        }

        private void InitializeDebugEnabled(XmlElement section, Settings parent)
        {
            var debugEnabled = section.GetAttribute(NodeConstants.DebugEnabled);
            DebugEnabled = string.IsNullOrEmpty(debugEnabled) 
                ? parent.DefaultDebugEnabled 
                : bool.Parse(debugEnabled);
        }

        IEnumerator<Resource> IEnumerable<Resource>.GetEnumerator()
        {
            foreach (var resource in resources)
            {
                yield return resource;
            }
        }

        IEnumerator IEnumerable.GetEnumerator()
        {
            return ((IEnumerable<Resource>)this).GetEnumerator();
        }

        public override bool Equals(object obj)
        {
            if (obj == this)
                return true;
            if (!(obj is ResourceSet))
                return false;
            return Name.Equals(((ResourceSet)obj).Name);
        }

        public override int GetHashCode()
        {
            return Name.GetHashCode();
        } 
    }
}