//
// Author:
//   Jb Evain (jbevain@gmail.com)
//
// Copyright (c) 2008 - 2015 Jb Evain
// Copyright (c) 2008 - 2011 Novell, Inc.
//
// Licensed under the MIT/X11 license.
//

using MonoFN.Collections.Generic;
using System.Text;
using System.Threading;

namespace MonoFN.Cecil
{
    public sealed class PropertyDefinition : PropertyReference, IMemberDefinition, IConstantProvider
    {
        private bool? has_this;
        private ushort attributes;
        private Collection<CustomAttribute> custom_attributes;
        internal MethodDefinition get_method;
        internal MethodDefinition set_method;
        internal Collection<MethodDefinition> other_methods;
        private object constant = Mixin.NotResolved;
        public PropertyAttributes Attributes
        {
            get { return (PropertyAttributes)attributes; }
            set { attributes = (ushort)value; }
        }
        public bool HasThis
        {
            get
            {
                if (has_this.HasValue)
                    return has_this.Value;

                if (GetMethod != null)
                    return get_method.HasThis;

                if (SetMethod != null)
                    return set_method.HasThis;

                return false;
            }
            set { has_this = value; }
        }
        public bool HasCustomAttributes
        {
            get
            {
                if (custom_attributes != null)
                    return custom_attributes.Count > 0;

                return this.GetHasCustomAttributes(Module);
            }
        }
        public Collection<CustomAttribute> CustomAttributes
        {
            get { return custom_attributes ?? this.GetCustomAttributes(ref custom_attributes, Module); }
        }
        public MethodDefinition GetMethod
        {
            get
            {
                if (get_method != null)
                    return get_method;

                InitializeMethods();
                return get_method;
            }
            set { get_method = value; }
        }
        public MethodDefinition SetMethod
        {
            get
            {
                if (set_method != null)
                    return set_method;

                InitializeMethods();
                return set_method;
            }
            set { set_method = value; }
        }
        public bool HasOtherMethods
        {
            get
            {
                if (other_methods != null)
                    return other_methods.Count > 0;

                InitializeMethods();
                return !other_methods.IsNullOrEmpty();
            }
        }
        public Collection<MethodDefinition> OtherMethods
        {
            get
            {
                if (other_methods != null)
                    return other_methods;

                InitializeMethods();

                if (other_methods != null)
                    return other_methods;

                Interlocked.CompareExchange(ref other_methods, new(), null);
                return other_methods;
            }
        }
        public bool HasParameters
        {
            get
            {
                InitializeMethods();

                if (get_method != null)
                    return get_method.HasParameters;

                if (set_method != null)
                    return set_method.HasParameters && set_method.Parameters.Count > 1;

                return false;
            }
        }
        public override Collection<ParameterDefinition> Parameters
        {
            get
            {
                InitializeMethods();

                if (get_method != null)
                    return MirrorParameters(get_method, 0);

                if (set_method != null)
                    return MirrorParameters(set_method, 1);

                return new();
            }
        }

        private static Collection<ParameterDefinition> MirrorParameters(MethodDefinition method, int bound)
        {
            Collection<ParameterDefinition> parameters = new();
            if (!method.HasParameters)
                return parameters;

            Collection<ParameterDefinition> original_parameters = method.Parameters;
            int end = original_parameters.Count - bound;

            for (int i = 0; i < end; i++)
                parameters.Add(original_parameters[i]);

            return parameters;
        }

        public bool HasConstant
        {
            get
            {
                this.ResolveConstant(ref constant, Module);

                return constant != Mixin.NoValue;
            }
            set
            {
                if (!value)
                    constant = Mixin.NoValue;
            }
        }
        public object Constant
        {
            get { return HasConstant ? constant : null; }
            set { constant = value; }
        }

        #region PropertyAttributes
        public bool IsSpecialName
        {
            get { return attributes.GetAttributes((ushort)PropertyAttributes.SpecialName); }
            set { attributes = attributes.SetAttributes((ushort)PropertyAttributes.SpecialName, value); }
        }
        public bool IsRuntimeSpecialName
        {
            get { return attributes.GetAttributes((ushort)PropertyAttributes.RTSpecialName); }
            set { attributes = attributes.SetAttributes((ushort)PropertyAttributes.RTSpecialName, value); }
        }
        public bool HasDefault
        {
            get { return attributes.GetAttributes((ushort)PropertyAttributes.HasDefault); }
            set { attributes = attributes.SetAttributes((ushort)PropertyAttributes.HasDefault, value); }
        }
        #endregion

        public new TypeDefinition DeclaringType
        {
            get { return (TypeDefinition)base.DeclaringType; }
            set { base.DeclaringType = value; }
        }
        public override bool IsDefinition
        {
            get { return true; }
        }
        public override string FullName
        {
            get
            {
                StringBuilder builder = new();
                builder.Append(PropertyType.ToString());
                builder.Append(' ');
                builder.Append(MemberFullName());
                builder.Append('(');
                if (HasParameters)
                {
                    Collection<ParameterDefinition> parameters = Parameters;
                    for (int i = 0; i < parameters.Count; i++)
                    {
                        if (i > 0)
                            builder.Append(',');
                        builder.Append(parameters[i].ParameterType.FullName);
                    }
                }
                builder.Append(')');
                return builder.ToString();
            }
        }

        public PropertyDefinition(string name, PropertyAttributes attributes, TypeReference propertyType) : base(name, propertyType)
        {
            this.attributes = (ushort)attributes;
            token = new(TokenType.Property);
        }

        private void InitializeMethods()
        {
            ModuleDefinition module = Module;
            if (module == null)
                return;

            lock (module.SyncRoot)
            {
                if (get_method != null || set_method != null)
                    return;

                if (!module.HasImage())
                    return;

                module.Read(this, (property, reader) => reader.ReadMethods(property));
            }
        }

        public override PropertyDefinition Resolve()
        {
            return this;
        }
    }
}