using System;
using JD.Kernel.StaticHelpers;
using JD.Kernel.Structs;
using JD.LogService;
using JD.Serializers.Xml;

namespace JD.TeaBoxAddinSystem.Addins.Management
{
    /// <summary>
    /// Helper class used to deserialize an addin or other addin objects from xml.
    /// </summary>
    public abstract class AddinXmlSerializer
    {
        #region Constants

        #region Nodes and attributes

        internal const string IdAttribute = "id";
        internal const string NameAttribute = "name";
        internal const string DeprecatedAttribute = "deprecated";
        internal const string VersionAttribute = "version";
        internal const string AuthorAttribute = "author";
        internal const string UrlAttribute = "url";
        internal const string DescriptionAttribute = "description";
        internal const string CategoryAttribute = "category";
        internal const string X86OnlyAttribute = "x86_only";

        internal const string FilesNode = "Files";
        internal const string ImportNode = "Import";
        internal const string AssemblyAttribute = "assembly";
        internal const string ResourceAttribute = "resource";
        internal const string FileAttribute = "file";

        internal const string DependenciesNode = "Dependencies";
        internal const string AddinNode = "Addin";

        internal const string ExtensionNode = "Extension";
        internal const string ExtensionPointNode = "ExtensionPoint";
        internal const string PathAttribute = "path";

        internal const string ModuleNode = "Module";
        internal const string IncludeNode = "Include";

        internal const string ExtensionNodeSetNode = "ExtensionNodeSet";
        internal const string ExtensionNodeNode = "ExtensionNode";
        internal const string DescriptionNode = "Description";
        internal const string TypeAttribute = "type";
        internal const string ObjectTypeAttribute = "object";

        internal const string ConditionNodeNode = "ConditionNode";
        internal const string ConditionPrefix = "If";
        internal const string AndNode = "And";
        internal const string OrNode = "Or";
        internal const string XorNode = "Xor";
        internal const string NotNode = "Not";
        internal const string TrueNode = "True";
        internal const string FalseNode = "False";
        internal const string TargetAttribute = "target";

        #endregion

        #region Messages

        internal const string InvalidOrMissingAttribute = "Invalid or missing \"{0}\" attribute in \"{1}\" element";
        internal const string ElementMustBeEmpty = "\"{0}\" elements must be empty";
        internal const string UnexpectedXmlElement = "Unexpected xml element \"{0}\"";

        #endregion

        #endregion

        #region Variables

        /// <summary>
        /// Logger.
        /// </summary>
        protected readonly ILogger m_logger;

        #endregion

        #region Constructor

        internal AddinXmlSerializer(ILogger logger)
        {
            Throw.IfNull(logger, "logger");
            m_logger = logger;
        }

        #endregion

        #region Properties

        /// <summary>
        /// Current File Location.
        /// </summary>
        protected abstract FileLocation CurrentFileLocation
        {
            get;
        }

        #endregion

        #region Methods

        #region Static Methods

        /// <summary>
        /// Reads an addin from the given <paramref name="reader"/>.
        /// </summary>
        /// <param name="reader"></param>
        /// <param name="logger"></param>
        /// <returns></returns>
        public static Addin ReadAddin(XmlSerializerReader reader, ILogger logger)
        {
            return new AddinXmlSerializerReaderSerializer(reader, logger).Serialize();
        }

        #endregion        

        /// <summary>
        /// Serializes the addin.
        /// </summary>
        /// <returns></returns>
        protected abstract Addin Serialize();

        /// <summary>
        /// Parses a version from a string.
        /// </summary>
        /// <param name="version"></param>
        /// <returns></returns>
        protected Version ParseVersion(string version)
        {
            if (string.IsNullOrEmpty(version))
            {
                return null;
            }

            try
            {
                return new Version(version);
            }
            catch (Exception e)
            {
                LogError($"Cannot convert '{version}' to a version: {e.Message}");
                return null;
            }
        }

        /// <summary>
        /// Logs a message.
        /// </summary>
        /// <param name="message"></param>
        /// <param name="importance"></param>
        protected void LogMessage(string message, MessageImportance importance)
        {
            m_logger.Log(new Message(message) { Importance = importance });
        }

        /// <summary>
        /// Logs a warning.
        /// </summary>
        /// <param name="message"></param>
        protected void LogWarning(string message)
        {
            m_logger.Log(new Error(LogCategory.Warning, message) { Origin = CurrentFileLocation });
        }

        /// <summary>
        /// Logs an error.
        /// </summary>
        /// <param name="message"></param>
        protected void LogError(string message)
        {
            m_logger.Log(new Error(LogCategory.Error, message) { Origin = CurrentFileLocation });
        }        

        /// <summary>
        /// Logs an unexpected xml node.
        /// </summary>
        /// <param name="actualNode"></param>
        protected void LogUnexpectedXmlElement(string actualNode)
        {
            LogError(string.Format(UnexpectedXmlElement, actualNode));
        }

        /// <summary>
        /// Logs an invalid attribute node.
        /// </summary>
        /// <param name="attribute"></param>
        /// <param name="node"></param>
        protected void LogInvalidAttributeElement(string attribute, string node)
        {
            LogError(string.Format(InvalidOrMissingAttribute, attribute, node));
        }

        /// <summary>
        /// Logs a duplicate node.
        /// </summary>
        /// <param name="nodeType"></param>
        /// <param name="nodeName"></param>
        /// <param name="existingLocation"></param>
        protected void LogDuplicateElement(string nodeType, string nodeName, FileLocation? existingLocation)
        {
            System.Diagnostics.Debug.Assert(!string.IsNullOrEmpty(nodeType));
            System.Diagnostics.Debug.Assert(!string.IsNullOrEmpty(nodeName));

            LogError($"Another {nodeType} named \"{nodeName}\" was already defined earlier in this context at {existingLocation}");
        }

        /// <summary>
        /// Logs an already defined description.
        /// </summary>
        /// <param name="name"></param>
        /// <param name="existingLocation"></param>
        protected void LogDescriptionAlreadyDefined(string name, FileLocation? existingLocation)
        {
            System.Diagnostics.Debug.Assert(!string.IsNullOrEmpty(name));            

            LogWarning($"Description of \"{name}\" will be ignored because it was already defined earlier at {existingLocation}");
        }

        #endregion
    }
}