using System;

using System.Collections.Generic;

using System.Xml.Linq;

using System.Xml.XPath;

using System.Xml;

using System.Linq;

using System.Text;



namespace LateBindingApi.CodeGenerator.VB

{

    class CustomMethodManager

    {

        VBGenerator _parent;

        XDocument _document;

        XDocument _derived;



        internal CustomMethodManager(VBGenerator parent, XDocument document)

        {

            _parent = parent;

            _document = document;

        }



        public void ScanForOptionalMethods()

        {

            _derived = new XDocument();

            _derived.Add(new XElement("Document"));



            ScanForDerived("DispatchInterfaces", "Interface", "Methods", "Method");

            ScanForDerived("Interfaces", "Interface", "Methods", "Method");

            ScanForDerived("DispatchInterfaces", "Interface", "Properties", "Property");

            ScanForDerived("Interfaces", "Interface", "Properties", "Property");

        }



        private XElement GetMethodOverload(XElement itemMethod, IEnumerable<XElement> listParameters, int paramsCount)

        {

            foreach (XElement itemParameters in itemMethod.Elements("Parameters"))

            {

                if (itemParameters.Elements("Parameter").Count() == paramsCount)

                    return itemParameters;

            }



            foreach (XElement itemParameters in listParameters)

            {

                if (itemParameters.Elements("Parameter").Count() == paramsCount)

                    return itemParameters;

            }

            return null;

        }



        private XElement CloneParametersNode(XElement itemParameters, int parametersCount)

        {

            XElement itemMethod = itemParameters.Parent;

            XElement newParameters = new XElement("Parameters", new XAttribute("IsCustom","true"));



            if (itemParameters.Element("ReturnValue") != null)

            {

                newParameters.Add(new XElement("ReturnValue"));

                foreach (XAttribute item in itemParameters.Element("ReturnValue").Attributes())

                    newParameters.Element("ReturnValue").Add(new XAttribute(item.Name, item.Value));

            }



            newParameters.Add(new XElement("RefLibraries"));

            foreach (XElement item in itemParameters.Element("RefLibraries").Elements("Ref"))

            {

                XElement newRef = new XElement(item.Name, item.Value);

                newRef.Add(new XAttribute("Key", item.Attribute("Key").Value));

                newParameters.Element("RefLibraries").Add(newRef);

            }



            int i = 1;

            foreach (XElement item in itemParameters.Elements("Parameter"))

            {

                if (i > parametersCount)

                    break;

                XElement newParameter = new XElement("Parameter");

                foreach (XAttribute itemAttribute in item.Attributes())

                    newParameter.Add(new XAttribute(itemAttribute.Name, itemAttribute.Value));

                newParameters.Add(newParameter);

                i++;

            }



            return newParameters;

        }



        private void ScanForDerived(string elements, string element, string enumsNode, string entity)

        {

            var interfaces = (from a in _document.Element("LateBindingApi.CodeGenerator.Document").Element("Solution").Element("Projects").Elements("Project").

                                 Elements(elements).Elements(element) select a);



            foreach (XElement itemFace in interfaces)

            {

                foreach (XElement itemMethod in itemFace.Element(enumsNode).Elements(entity))

                {

                    List<XElement> newParameters = new List<XElement>();

                    IEnumerable<XElement> listParameters = itemMethod.Elements("Parameters");

                    foreach (XElement itemParameters in listParameters)

                    {

                        IEnumerable<XElement> nonOptionalParamNodes = (from a in itemParameters.Elements("Parameter") where a.Attribute("IsOptional").Value.Equals("false", StringComparison.InvariantCultureIgnoreCase) select a);

                        int nonOptionalsCount = nonOptionalParamNodes.Count();



                        IEnumerable<XElement> optionalParamNodes = (from a in itemParameters.Elements("Parameter")

                                         where a.Attribute("IsOptional").Value.Equals("true", StringComparison.InvariantCultureIgnoreCase) select a);

                        int optionalsCount = optionalParamNodes.Count();



                        if (optionalsCount > 0)

                        {

                            for (int i = nonOptionalsCount; i < (nonOptionalsCount+optionalsCount); i++)

                            {

                                XElement existingMethodOverload = GetMethodOverload(itemMethod, newParameters, i);

                                if (null == existingMethodOverload)

                                {

                                    bool clone = true;

                                    if ((i == 0) && (IsDefaultItem(itemParameters)))

                                        clone = false;

                                    if (clone)

                                    { 

                                        XElement newParameter = CloneParametersNode(itemParameters, i);

                                        newParameters.Add(newParameter);

                                    }

                                }

                            }

                        }

                    }



                    foreach (XElement item in newParameters)

                        itemMethod.Add(item);

	            }

            }

        }



        private static bool IsDefaultItem(XElement itemParams)

        {

            XElement itemMethod = itemParams.Parent;



            XElement node = (from a in itemMethod.Element("DispIds").Elements("DispId")

                             where a.Attribute("Id").Value.Equals("0", StringComparison.InvariantCultureIgnoreCase)

                             select a).FirstOrDefault();



            return (node != null);

        }



        private XElement GetCountNode(XElement itemFace)

        {

            XElement node = (from a in itemFace.Element("Properties").Elements("Property")

                             where a.Attribute("Name").Value.Equals("Count", StringComparison.InvariantCultureIgnoreCase)

                             select a).FirstOrDefault();

            if (null != node)

            {

                string type = (node.Element("Parameters").Element("ReturnValue").Attribute("Type").Value);

                if ("Int32" == type)

                    return node;

            }



            node = (from a in itemFace.Element("Methods").Elements("Method")

                    where a.Attribute("Name").Value.Equals("Count", StringComparison.InvariantCultureIgnoreCase)

                    select a).FirstOrDefault();

            if (null != node)

                return node;



            return null;

        }



        private XElement GetDefaultItemNode(XElement itemFace)

        {

            XElement node = null;



            foreach (XElement itemMethod in itemFace.Element("Properties").Elements("Property"))

            {

                node = (from a in itemMethod.Element("DispIds").Elements("DispId")

                        where a.Attribute("Id").Value.Equals("0", StringComparison.InvariantCultureIgnoreCase)

                        select a).FirstOrDefault();

                if (null != node)

                    return itemMethod;

            }



            foreach (XElement itemMethod in itemFace.Element("Methods").Elements("Method"))

            {

                node = (from a in itemMethod.Element("DispIds").Elements("DispId")

                        where a.Attribute("Id").Value.Equals("0", StringComparison.InvariantCultureIgnoreCase)

                        select a).FirstOrDefault();

                if (null != node)

                    return itemMethod;

            }



            return null;

        }



        private XElement GetEnumeratorNode(XElement itemFace)

        {

            XElement node = (from a in itemFace.Element("Properties").Elements("Property")

                             where a.Attribute("Name").Value.Equals("_NewEnum", StringComparison.InvariantCultureIgnoreCase)

                             select a).FirstOrDefault();

            if (null != node)

                return node;



            node = (from a in itemFace.Element("Methods").Elements("Method")

                    where a.Attribute("Name").Value.Equals("_NewEnum", StringComparison.InvariantCultureIgnoreCase)

                    select a).FirstOrDefault();

            if (null != node)

                return node;



            return null;

        }



        private void AddType(XElement type)

        {

            string id = type.Attribute("Key").Value;

            XElement node = (from a in _derived.Element("Document").Elements("Type")

                             where a.Attribute("Key").Value.Equals(id, StringComparison.InvariantCultureIgnoreCase)

                             select a).FirstOrDefault();

            if (null == node)

            {

                string name = type.Attribute("Name").Value;

                _derived.Element("Document").Add(new XElement("Type", new XAttribute("Name", name), new XAttribute("Key", id)));

            }

        }



        private XElement GetTypeByName(XElement projectNode, string name)

        {



            XElement node = (from a in projectNode.Element("DispatchInterfaces").Elements("Interface")

                             where a.Attribute("Name").Value.Equals(name, StringComparison.InvariantCultureIgnoreCase)

                             select a).FirstOrDefault();



            if (null != node)

                return node;



            node = (from a in projectNode.Element("Interfaces").Elements("Interface")

                    where a.Attribute("Name").Value.Equals(name, StringComparison.InvariantCultureIgnoreCase)

                    select a).FirstOrDefault();



            if (null != node)

                return node;



            node = (from a in projectNode.Element("CoClasses").Elements("CoClass")

                    where a.Attribute("Name").Value.Equals(name, StringComparison.InvariantCultureIgnoreCase)

                    select a).FirstOrDefault();



            if (null != node)

                return node;



            throw new Exception("name not found " + name);

        }

   

        private bool HasAttriute(XElement node, string attributeName)

        {

            foreach (XAttribute item in node.Attributes())

            {

                if (item.Name == attributeName)

                    return true;

            }



            return false;

        }



        private XElement GetProjectNode(XElement returnValue)

        {

            XElement projectNode = returnValue.Parent;

            while (projectNode.Name != "Project")

                projectNode = projectNode.Parent;



            return projectNode;

        }



        public bool IsDerivedReturnValue(XElement returnValue)

        {

            string typeKey = returnValue.Attribute("TypeKey").Value;

            if (string.IsNullOrEmpty(typeKey))

            {

                if (returnValue.Attribute("IsExternal").Value.Equals("true", StringComparison.InvariantCultureIgnoreCase))

                    return false;



                XElement projectNode = GetProjectNode(returnValue);

                XElement interfaceNode = GetTypeByName(projectNode, returnValue.Attribute("Type").Value as string);

                string id = interfaceNode.Attribute("Key").Value;

                return IsDerived(id);

            }

            else

            {

                XElement interfaceNode = VBGenerator.GetInterfaceOrClassFromKey(typeKey);

                string id = interfaceNode.Attribute("Key").Value;

                return IsDerived(id);

            }

        }



        public bool IsDerived(string id)

        {

            XElement node = (from a in _derived.Element("Document").Elements("Type")

                             where a.Attribute("Key").Value.Equals(id, StringComparison.InvariantCultureIgnoreCase)

                             select a).FirstOrDefault();

            return (node != null);

        }

    }

}