/4.0/Source/Core/Utilities/GlobalScope.cs

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Dynamic;

using System.Linq.Expressions;

using PHP.Core.Reflection;

using PHP.Core.Binders;

using PHP.Core.Emit;

using System.Diagnostics;



namespace PHP.Core.Utilities

{

    #region BaseScope



    /// <summary>

    /// Base class for all the convenience dynamic objects for accessing global elements 

    /// </summary>

    public abstract class BaseScope : DynamicObject

    {

        private ScriptContext context;

        private string ns;

        private string nsSlash;



        protected const string ConstID = "const";

        protected const string NamespaceID = "namespace";

        protected const string ClassID = "class";



        public string Namespace

        {

            get { return ns; }

        }



        public bool UseNamespaces

        {

            get { return ns != null; }

        }



        public ScriptContext Context

        {

            get { return context; }

        }



        internal BaseScope(ScriptContext context)

        {

            this.context = context;

        }



        internal BaseScope(ScriptContext context, string namespaceName)

            :this(context)

        {

            this.ns = namespaceName;

            this.nsSlash = this.ns + QualifiedName.Separator;

        }



        /// <summary>

        /// Transforms given name to be full name including namespaces

        /// </summary>

        public string GetFullName(string name)

        {

            if (UseNamespaces)

                return nsSlash + name;



            return name;

        }



        /// <summary>

        /// Wrap all arguments to Phalanger objects only if the type is not primitive

        /// </summary>

        /// <param name="args"></param>

        /// <returns></returns>

        protected static object[] wrapArgs(Object[] args)

        {

            object[] wrappedArgs = new object[args.Length];



            for (int i = 0; i < args.Length; ++i)

            {

                Debug.Assert(!(args[i] is PhpReference));

                wrappedArgs[i] = ClrObject.WrapDynamic(args[i]);

            }

            return wrappedArgs;

        }

    }



    #endregion



    #region GlobalScope



    /// <summary>

    /// Convenience class for accessing global functions and global variables

    /// </summary>

    public class GlobalScope : BaseScope

    {

        private ClassesScope classes;

        private NamespaceScope namespaces;

        private ConstsScope consts;



        /// <summary>

        /// Gets ClassesScope dynamic object that represents types defined in global scope

        /// </summary>

        protected ClassesScope Classes

        {

            get

            {

                if (classes == null)

                {

                    if (UseNamespaces)

                        classes = new ClassesScope(this.Context, Namespace);

                    else

                        classes = new ClassesScope(this.Context);

                }



                return classes;

            }

        }



        /// <summary>

        /// Gets ConstsScope dynamic object that represents types defined in global scope

        /// </summary>

        protected ConstsScope Consts

        {

            get

            {

                if (consts == null)

                {

                    if (UseNamespaces)

                        consts = new ConstsScope(this.Context, Namespace);

                    else

                        consts = new ConstsScope(this.Context);

                }



                return consts;

            }

        }



        /// <summary>

        /// Gets NamespaceScope dynamic object that represents namespaces defined in global scope

        /// </summary>

        private NamespaceScope Namespaces

        {

            get

            {

                if (namespaces == null)

                    namespaces = new NamespaceScope(this.Context);



                return namespaces;

            }

        }



        /// <summary>

        /// Initialize GlobalScope object

        /// </summary>

        /// <param name="currentContext"></param>

        internal GlobalScope(ScriptContext currentContext)

            : base(currentContext)

        {

        }



        /// <summary>

        /// Initialize GlobalScope object with namespace specified

        /// </summary>

        /// <param name="currentContext"></param>

        /// <param name="namespaceName"></param>

        protected GlobalScope(ScriptContext currentContext, string namespaceName)

            : base(currentContext, namespaceName)

        {

        }





        #region DynamicObject



        /// <summary>

        /// Specifies dynamic behavior for invoke operation for global function

        /// </summary>

        public override bool TryInvokeMember(

            InvokeMemberBinder binder,

            Object[] args,

            out Object result

        )

        {

            return TryInvokeMember(binder.Name, args, out result);

        }



        /// <summary>

        /// Specifies dynamic behavior for get operation for global variable

        /// </summary>

        public override bool TryGetMember(

            GetMemberBinder binder,

            out Object result

        )

        {

            switch (binder.Name)

            {

                case ClassID:

                    result = Classes;

                    return true;



                case ConstID:

                    result = Consts;

                    return true;



                case NamespaceID:

                    result = Namespaces;

                    return true;

            }



            result = PhpVariable.Unwrap(Operators.GetVariable(Context, null, binder.Name));

            return true;

        }



        /// <summary>

        /// Specifies dynamic behavior for set operation for global function

        /// </summary>

        public override bool TrySetMember(

            SetMemberBinder binder,

            Object value

        )

        {

            return TrySetMember(binder.Name, value);

        }



        #endregion





        /// <summary>

        /// Specifies dynamic behavior for invoke operation for global function

        /// </summary>

        public bool TryInvokeMember(

            string memberName,

            Object[] args,

            out Object result

        )

        {

            result = PhpVariable.Unwrap(PhpVariable.Dereference(Context.Call(memberName, null, null, wrapArgs(args))));

            return true;

        }



        public bool TrySetMember(

            string memberName,

            Object value)

        {

            Operators.SetVariable(Context, null, memberName, ClrObject.WrapDynamic(value));

            return true;

        }



    }



    #endregion



    #region NamespaceScope



    /// <summary>

    /// Dynamic Obeject for representing PHP namespaces

    /// </summary>

    public class NamespaceScope : GlobalScope

    {



        internal NamespaceScope(ScriptContext context)

            : base(context)

        {

        }



        private NamespaceScope(ScriptContext context, string namespaceName)

            : base(context, namespaceName)

        {

        }



        /// <summary>

        /// Specifies dynamic behavior for invoke operation for global function

        /// </summary>

        public override bool TryInvokeMember(

            InvokeMemberBinder binder,

            Object[] args,

            out Object result

        )

        {

            return TryInvokeMember(GetFullName(binder.Name), args, out result);

        }



        /// <summary>

        /// Specifies dynamic behavior for get operation for global variable in namespace

        /// </summary>

        public override bool TryGetMember(

            GetMemberBinder binder,

            out Object result

        )

        {

            switch (binder.Name)

            {

                case ClassID:

                    result = Classes;

                    return true;



                case ConstID:

                    result = Consts;

                    return true;

            }



            result = new NamespaceScope(Context, GetFullName(binder.Name));



            return true;

        }



        /// <summary>

        /// Specifies dynamic behavior for set operation for global function in namespace

        /// </summary>

        public override bool TrySetMember(

            SetMemberBinder binder,

            Object value

        )

        {

            TrySetMember(GetFullName(binder.Name),value);

            return true;

        }



    }



    #endregion



    #region ClassScope



    /// <summary>

    /// Dynamic scope for reprensenting static members of class

    /// </summary>

    public class ClassScope : BaseScope

    {

        private DTypeDesc type;



        internal ClassScope(ScriptContext context, DTypeDesc type)

            : base(context)

        {

            this.type = type;

        }





        /// <summary>

        /// Specifies dynamic behavior for invoke operation for static method

        /// </summary>

        public override bool TryInvokeMember(

            InvokeMemberBinder binder,

            Object[] args,

            out Object result

        )

        {

            Context.Stack.AddFrame(wrapArgs(args));

            result = PhpVariable.Unwrap(PhpVariable.Dereference(Operators.InvokeStaticMethod(type, binder.Name, null, null, Context)));

            return true;

        }



        /// <summary>

        /// Specifies dynamic behavior for get operation for static variable

        /// </summary>

        public override bool TryGetMember(

            GetMemberBinder binder,

            out Object result

        )

        {

            if (binder.Name == ConstID)

            {

                result = new ConstsScope(Context,type);

                return true;

            }



            result = PhpVariable.Unwrap(PhpVariable.Dereference(Operators.GetStaticProperty(type, binder.Name, null, Context, false)));

            return true;

        }





        /// <summary>

        /// Specifies dynamic behavior for set operation for static variable

        /// </summary>

        public override bool TrySetMember(

            SetMemberBinder binder,

            Object value

        )

        {

            Operators.SetStaticProperty(type, binder.Name, ClrObject.WrapDynamic(value), null, Context);

            return true;



        }

    }



    #endregion



    #region ClassesScope



    /// <summary>

    /// Dynamic Object for representing PHP classes

    /// </summary>

    public class ClassesScope : BaseScope

    {



        internal ClassesScope(ScriptContext context)

            : base(context)

        {

        }



        internal ClassesScope(ScriptContext context, string namespaceName)

            : base(context, namespaceName)

        {

        }



        private DTypeDesc ResolveType(string name)

        {

            return Context.ResolveType(GetFullName(name), null, null, null, ResolveTypeFlags.UseAutoload | ResolveTypeFlags.ThrowErrors);

        }



        /// <summary>

        /// Creates new instance of specified PHP class 

        /// </summary>

        public override bool TryInvokeMember(

            InvokeMemberBinder binder,

            Object[] args,

            out Object result

        )

        {

            Context.Stack.AddFrame(wrapArgs(args));

            DTypeDesc type = ResolveType(binder.Name);

            result = Operators.New(type, null, Context, null);

            return true;

        }



        /// <summary>

        /// Gets dynamic object representing classes

        /// </summary>

        public override bool TryGetMember(

            GetMemberBinder binder,

            out Object result

        )

        {

            DTypeDesc resType = ResolveType(binder.Name);

            result = new ClassScope(Context, resType);

            return true;

        }



    }



    #endregion



    #region ConstsScope



    /// <summary>

    /// Dynamic Object for representing PHP constants

    /// </summary>

    public class ConstsScope : BaseScope

    {

        private DTypeDesc type;



        internal ConstsScope(ScriptContext context)

            : base(context)

        {

        }



        internal ConstsScope(ScriptContext context, string namespaceName)

            : base(context, namespaceName)

        {

        }



        internal ConstsScope(ScriptContext context, DTypeDesc type)

            : base(context)

        {

            this.type = type;

        }



        /// <summary>

        /// Specifies dynamic behavior for get operation for a constant

        /// </summary>

        public override bool TryGetMember(

            GetMemberBinder binder,

            out Object result

        )

        {

            if (type != null)

            {

                result = Operators.GetClassConstant(type, binder.Name, null, Context);

                return true;

            }



            result = Context.GetConstantValue(GetFullName(binder.Name), false, false);

            return true;

        }



        /// <summary>

        /// Specifies dynamic behavior for set operation for a constant

        /// </summary>

        public override bool TrySetMember(

            SetMemberBinder binder,

            Object value

        )

        {

            if (type != null)

            {

                PhpException.Throw(PhpError.Error, String.Format( PHP.Core.Localizations.Strings.constant_redefined, type.MakeFullName() + Name.ClassMemberSeparator + binder.Name));

                return true;

            }



            Context.DefineConstant(GetFullName(binder.Name), value);

            return true;



        }



    }



    #endregion

}