// Copyright (c) .NET Foundation and contributors. All rights reserved.
// Licensed under the MIT license. See LICENSE file in the project root for full license information.

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using Mono.Cecil;

namespace Mono.Linker
{
    public class AttributeInfo
    {
        public Dictionary<ICustomAttributeProvider, CustomAttribute[]> CustomAttributes { get; }

        public Dictionary<CustomAttribute, MessageOrigin> CustomAttributesOrigins { get; }

        public AttributeInfo()
        {
            CustomAttributes = new Dictionary<ICustomAttributeProvider, CustomAttribute[]>();
            CustomAttributesOrigins = new Dictionary<CustomAttribute, MessageOrigin>();
        }

        public void AddCustomAttributes(ICustomAttributeProvider provider, CustomAttribute[] customAttributes, MessageOrigin[] origins)
        {
            Debug.Assert(customAttributes.Length == origins.Length);

            AddCustomAttributes(provider, customAttributes);

            foreach (var (customAttribute, origin) in customAttributes.Zip(origins))
            {
                CustomAttributesOrigins.Add(customAttribute, origin);
            }
        }

        public void AddCustomAttributes(ICustomAttributeProvider provider, CustomAttribute[] customAttributes)
        {
            if (!CustomAttributes.TryGetValue(provider, out var existing))
            {
                CustomAttributes.Add(provider, customAttributes);
            }
            else
            {
                int existingLength = existing.Length;
                Array.Resize(ref existing, existingLength + customAttributes.Length);
                customAttributes.CopyTo(existing, existingLength);

                CustomAttributes[provider] = existing;
            }
        }
    }
}