// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
 
using System;
using System.Collections.Immutable;
using System.Linq;
using System.Runtime.Serialization;
using Roslyn.Utilities;
 
namespace Microsoft.CodeAnalysis.InheritanceMargin
{
    [DataContract]
    internal readonly struct InheritanceMarginItem : IEquatable<InheritanceMarginItem>
    {
        /// <summary>
        /// Line number used to show the margin for the member.
        /// </summary>
        [DataMember(Order = 0)]
        public readonly int LineNumber;
 
        /// <summary>
        /// Special display text to show when showing the 'hover' tip for a margin item.  Used to override the default
        /// text we show that says "'X' is inherited".  Used currently for showing information about top-level-imports.
        /// </summary>
        [DataMember(Order = 1)]
        public readonly string? TopLevelDisplayText;
 
        /// <summary>
        /// Display texts for this member.
        /// </summary>
        [DataMember(Order = 2)]
        public readonly ImmutableArray<TaggedText> DisplayTexts;
 
        /// <summary>
        /// Member's glyph.
        /// </summary>
        [DataMember(Order = 3)]
        public readonly Glyph Glyph;
 
        /// <summary>
        /// An array of the implementing/implemented/overriding/overridden targets for this member.
        /// </summary>
        [DataMember(Order = 4)]
        public readonly ImmutableArray<InheritanceTargetItem> TargetItems;
 
        public InheritanceMarginItem(
            int lineNumber,
            string? topLevelDisplayText,
            ImmutableArray<TaggedText> displayTexts,
            Glyph glyph,
            ImmutableArray<InheritanceTargetItem> targetItems)
        {
            LineNumber = lineNumber;
            TopLevelDisplayText = topLevelDisplayText;
            DisplayTexts = displayTexts;
            Glyph = glyph;
            TargetItems = targetItems;
        }
 
        public override int GetHashCode()
            => throw ExceptionUtilities.Unreachable();
 
        public override bool Equals(object? obj)
            => obj is InheritanceMarginItem item && Equals(item);
 
        public bool Equals(InheritanceMarginItem other)
            => this.LineNumber == other.LineNumber &&
               this.TopLevelDisplayText == other.TopLevelDisplayText &&
               this.Glyph == other.Glyph &&
               this.DisplayTexts.SequenceEqual(other.DisplayTexts) &&
               this.TargetItems.SequenceEqual(other.TargetItems);
 
        public static InheritanceMarginItem? CreateOrdered(
            int lineNumber,
            string? topLevelDisplayText,
            ImmutableArray<TaggedText> displayTexts,
            Glyph glyph,
            ImmutableArray<InheritanceTargetItem> targetItems)
            => targetItems.IsEmpty ? null : new(lineNumber, topLevelDisplayText, displayTexts, glyph, Order(targetItems));
 
        public static ImmutableArray<InheritanceTargetItem> Order(ImmutableArray<InheritanceTargetItem> targetItems)
            => targetItems.OrderBy(t => t.DisplayName).ThenByDescending(t => t.LanguageGlyph).ThenBy(t => t.ProjectName ?? "").ToImmutableArray();
    }
}