//---------------------------------------------------------------------
// <copyright file="StructuredTypeEmitter.cs" company="Microsoft">
//      Copyright (c) Microsoft Corporation.  All rights reserved.
// </copyright>
//
// @owner       Microsoft
// @backupOwner Microsoft
//---------------------------------------------------------------------
using System;
using System.Collections;
using System.Collections.Generic;
using System.CodeDom;
using System.Data;
using System.Data.EntityModel.SchemaObjectModel;
using Som = System.Data.EntityModel.SchemaObjectModel;
using System.Data.Entity.Design;
using System.Data.Metadata.Edm;
using System.Diagnostics;
using System.Reflection;
using System.Data.Objects.DataClasses;
using System.Data.Entity.Design.Common;
using System.Data.Entity.Design.SsdlGenerator;
 
 
namespace System.Data.EntityModel.Emitters
{
    /// <summary>
    /// Summary description for StructuredTypeEmitter.
    /// </summary>
    internal abstract class StructuredTypeEmitter : SchemaTypeEmitter
    {
        #region Public Methods
        private bool _usingStandardBaseClass = true;
 
 
 
        /// <summary>
        /// 
        /// </summary>
        /// <returns></returns>
        public override CodeTypeDeclarationCollection EmitApiClass()
        {
            Validate(); // emitter-specific validation
 
            CodeTypeReference baseType = this.GetBaseType();
 
            // raise the TypeGenerated event
            TypeGeneratedEventArgs eventArgs = new TypeGeneratedEventArgs(Item, baseType);
            this.Generator.RaiseTypeGeneratedEvent(eventArgs);
 
            // public [abstract] partial class ClassName
            CodeTypeDeclaration typeDecl = new CodeTypeDeclaration(Item.Name);
            typeDecl.IsPartial = true;
            typeDecl.TypeAttributes = System.Reflection.TypeAttributes.Class;
            if (Item.Abstract)
            {
                typeDecl.TypeAttributes |= System.Reflection.TypeAttributes.Abstract;
            }
 
            SetTypeVisibility(typeDecl);
 
            EmitTypeAttributes(Item.Name, typeDecl, eventArgs.AdditionalAttributes);
 
            // : baseclass
            AssignBaseType(typeDecl, baseType, eventArgs.BaseType);
 
            AddInterfaces(Item.Name, typeDecl, eventArgs.AdditionalInterfaces);
 
            CommentEmitter.EmitSummaryComments(Item, typeDecl.Comments);
 
            // Since abstract types cannot be instantiated, skip the factory method for abstract types
            if ( (typeDecl.TypeAttributes & System.Reflection.TypeAttributes.Abstract) == 0)
                EmitFactoryMethod(typeDecl);
 
            EmitProperties(typeDecl);
 
            // additional members, if provided by the event subscriber
            this.AddMembers(Item.Name, typeDecl, eventArgs.AdditionalMembers);
 
            CodeTypeDeclarationCollection typeDecls = new CodeTypeDeclarationCollection();
            typeDecls.Add(typeDecl);
            return typeDecls;
        }
 
        #endregion
 
        #region Protected Methods
 
        /// <summary>
        /// 
        /// </summary>
        /// <returns></returns>
        protected virtual CodeTypeReference GetBaseType()
        {
            if (Item.BaseType == null)
                return null;
 
            return Generator.GetLeastPossibleQualifiedTypeReference(Item.BaseType);
        }
 
        /// <summary>
        /// 
        /// </summary>
        /// <param name="generator"></param>
        /// <param name="structuredType"></param>
        protected StructuredTypeEmitter(ClientApiGenerator generator, StructuralType structuralType)
            : base(generator, structuralType)
        {
        }
 
        /// <summary>
        /// 
        /// </summary>
        /// <param name="typeDecl"></param>
        protected override void EmitTypeAttributes(CodeTypeDeclaration typeDecl)
        {
            Generator.AttributeEmitter.EmitTypeAttributes(this, typeDecl);
            base.EmitTypeAttributes(typeDecl);
        }
 
        /// <summary>
        /// 
        /// </summary>
        /// <param name="typeDecl"></param>
        protected virtual void EmitProperties(CodeTypeDeclaration typeDecl)
        {
 
            foreach (EdmProperty property in Item.GetDeclaredOnlyMembers<EdmProperty>())
            {
                PropertyEmitter propertyEmitter = new PropertyEmitter(Generator, property, _usingStandardBaseClass);
                propertyEmitter.Emit(typeDecl);
            }
        }
 
        protected abstract ReadOnlyMetadataCollection<EdmProperty> GetProperties();
    
        /// <summary>
        /// Emit static factory method which creates an instance of the class and initializes
        /// non-nullable properties (taken as arguments)
        /// </summary>
        /// <param name="typeDecl"></param>
        protected virtual void EmitFactoryMethod(CodeTypeDeclaration typeDecl)
        {
            
            
            // build list of non-nullable properties
            ReadOnlyMetadataCollection<EdmProperty> properties = GetProperties();
            List<EdmProperty> parameters = new List<EdmProperty>(properties.Count);
            foreach (EdmProperty property in properties)
            {
                bool include = IncludeFieldInFactoryMethod(property);
                if (include)
                {
                    parameters.Add(property);
                }
            }
 
            // if there are no parameters, we don't emit anything (1 is for the null element)
            // nor do we emit everything if this is the Ref propertied ctor and the parameter list is the same as the many parametered ctor
            if (parameters.Count < 1)
            {
                return;
            }
 
            CodeMemberMethod method = new CodeMemberMethod();
            Generator.AttributeEmitter.EmitGeneratedCodeAttribute(method);
 
            CodeTypeReference typeRef = TypeReference.FromString(Item.Name);
            UniqueIdentifierService uniqueIdentifierService = new UniqueIdentifierService(Generator.IsLanguageCaseSensitive, name => Utils.FixParameterName(name));
            string instanceName = uniqueIdentifierService.AdjustIdentifier(Item.Name);
 
            // public static Class CreateClass(...)
            method.Attributes = MemberAttributes.Static|MemberAttributes.Public;
            method.Name = "Create" + Item.Name;
            if (NavigationPropertyEmitter.IsNameAlreadyAMemberName(Item, method.Name, Generator.LanguageAppropriateStringComparer))
            {
                Generator.AddError(Strings.GeneratedFactoryMethodNameConflict(method.Name, Item.Name),
                    ModelBuilderErrorCode.GeneratedFactoryMethodNameConflict,
                    EdmSchemaErrorSeverity.Error, Item.FullName);
            }
 
            method.ReturnType = typeRef;
            
            // output method summary comments 
            CommentEmitter.EmitSummaryComments(Strings.FactoryMethodSummaryComment(Item.Name), method.Comments);
 
 
            // Class class = new Class();
            CodeVariableDeclarationStatement createNewInstance = new CodeVariableDeclarationStatement(
                typeRef, instanceName, new CodeObjectCreateExpression(typeRef));
            method.Statements.Add(createNewInstance);
            CodeVariableReferenceExpression instanceRef = new CodeVariableReferenceExpression(instanceName);
 
            // iterate over the properties figuring out which need included in the factory method
            foreach (EdmProperty property in parameters)
            {
                // CreateClass( ... , propType propName ...)
                PropertyEmitter propertyEmitter = new PropertyEmitter(Generator, property, UsingStandardBaseClass);
                CodeTypeReference propertyTypeReference = propertyEmitter.PropertyType;
                String parameterName = uniqueIdentifierService.AdjustIdentifier(propertyEmitter.PropertyName);
                CodeParameterDeclarationExpression paramDecl = new CodeParameterDeclarationExpression(
                    propertyTypeReference, parameterName);
                CodeArgumentReferenceExpression paramRef = new CodeArgumentReferenceExpression(paramDecl.Name);
                method.Parameters.Add(paramDecl);
 
                // add comment describing the parameter
                CommentEmitter.EmitParamComments(paramDecl, Strings.FactoryParamCommentGeneral(propertyEmitter.PropertyName), method.Comments);
 
                CodeExpression newPropertyValue;
                if (MetadataUtil.IsComplexType(propertyEmitter.Item.TypeUsage.EdmType))
                {
                    List<CodeExpression> complexVerifyParameters = new List<CodeExpression>();
                    complexVerifyParameters.Add(paramRef);
                    complexVerifyParameters.Add(new CodePrimitiveExpression(propertyEmitter.PropertyName));
                    
                    newPropertyValue =
                        new CodeMethodInvokeExpression(
                            PropertyEmitter.CreateEdmStructuralObjectRef(TypeReference),
                            Utils.VerifyComplexObjectIsNotNullName,
                            complexVerifyParameters.ToArray());
                }
                else
                {
                    newPropertyValue = paramRef;
                }
 
                // Scalar property:
                //     Property = param;
                // Complex property:
                //     Property = StructuralObject.VerifyComplexObjectIsNotNull(param, propertyName);
 
                method.Statements.Add(new CodeAssignStatement(new CodePropertyReferenceExpression(instanceRef, propertyEmitter.PropertyName), newPropertyValue));            
            }
 
            // return class;
            method.Statements.Add(new CodeMethodReturnStatement(instanceRef));
 
            // actually add the method to the class
            typeDecl.Members.Add(method);
        }
        
 
        #endregion
        
        #region Protected Properties
 
        internal new StructuralType Item
        {
            get
            {
                return base.Item as StructuralType;
            }
        }
 
        protected bool UsingStandardBaseClass
        {
            get { return _usingStandardBaseClass; }
        }
 
        #endregion
            
        #region Private Methods
 
        /// <summary>
        /// 
        /// </summary>
        /// <param name="property"></param>
        /// <returns></returns>
        private bool IncludeFieldInFactoryMethod(EdmProperty property)
        {
            if (property.Nullable)
            {
                return false;
            }
 
            if (PropertyEmitter.HasDefault(property))
            {
                return false;
            }
 
            if ((PropertyEmitter.GetGetterAccessibility(property) != MemberAttributes.Public &&
                PropertyEmitter.GetSetterAccessibility(property) != MemberAttributes.Public) ||
                // declared in a sub type, but not setter accessbile from this type
                (Item != property.DeclaringType && PropertyEmitter.GetSetterAccessibility(property) == MemberAttributes.Private)
               )
            {
                return false;
            }
 
            return true;
        }
 
        private void AssignBaseType(CodeTypeDeclaration typeDecl,
                                    CodeTypeReference baseType,
                                    CodeTypeReference eventReturnedBaseType)
        {
            if (eventReturnedBaseType != null && !eventReturnedBaseType.Equals(baseType))
            {
                _usingStandardBaseClass = false;
                typeDecl.BaseTypes.Add(eventReturnedBaseType);
            }
            else 
            {
                if (baseType != null)
                {
                    typeDecl.BaseTypes.Add(baseType);
                }
            }
        }
        #endregion
    }
}