// 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.
 
#nullable disable
 
using System;
using System.Collections.Immutable;
using System.Linq;
 
namespace Microsoft.CodeAnalysis.Editor.UnitTests.Classification;
 
public class FormattedClassification
{
    private static readonly ImmutableDictionary<string, string> s_classificationPrefixToTestHelperMap = ImmutableDictionary<string, string>.Empty
        .Add("regex - ", "Regex.")
        .Add("json - ", "Json.")
        .Add("xml doc comment - ", "XmlDoc.")
        .Add("xml literal - ", "VBXml");
 
    public string ClassificationName { get; }
    public string Text { get; }
 
    private FormattedClassification() { }
 
    public FormattedClassification(string text, string classificationName)
    {
        Text = text ?? throw new ArgumentNullException(nameof(text));
        ClassificationName = classificationName ?? throw new ArgumentNullException(nameof(classificationName));
    }
 
    public override bool Equals(object obj)
    {
        if (obj is FormattedClassification other)
        {
            return this.ClassificationName == other.ClassificationName
                && this.Text == other.Text;
        }
 
        return false;
    }
 
    public override int GetHashCode()
        => ClassificationName.GetHashCode() ^ Text.GetHashCode();
 
    public override string ToString()
    {
        foreach (var kvp in s_classificationPrefixToTestHelperMap)
        {
            if (ClassificationName.StartsWith(kvp.Key))
            {
                var remainder = ClassificationName[kvp.Key.Length..];
                var parts = remainder.Split(' ');
                var type = string.Join("", parts.Select(Capitalize));
                return kvp.Value + $"{type}(\"{Text}\")";
            }
        }
 
        switch (ClassificationName)
        {
            case "punctuation":
                switch (Text)
                {
                    case "(":
                        return "Punctuation.OpenParen";
                    case ")":
                        return "Punctuation.CloseParen";
                    case "[":
                        return "Punctuation.OpenBracket";
                    case "]":
                        return "Punctuation.CloseBracket";
                    case "{":
                        return "Punctuation.OpenCurly";
                    case "}":
                        return "Punctuation.CloseCurly";
                    case ";":
                        return "Punctuation.Semicolon";
                    case ":":
                        return "Punctuation.Colon";
                    case ",":
                        return "Punctuation.Comma";
                    case "..":
                        return "Punctuation.DotDot";
                    case "<":
                        return "Punctuation.OpenAngle";
                    case ">":
                        return "Punctuation.CloseAngle";
                }
 
                goto default;
 
            case "operator":
            case "operator - overloaded":
                var operatorTypeName = ClassificationName switch
                {
                    "operator" => "Operators",
                    "operator - overloaded" => "OverloadedOperators",
                    _ => throw ExceptionUtilities.Unreachable(),
                };
 
                switch (Text)
                {
                    case "&&":
                        return $"{operatorTypeName}.AmpersandAmpersand";
                    case "&=":
                        return $"{operatorTypeName}.AmpersandEquals";
                    case "*":
                        return $"{operatorTypeName}.Asterisk";
                    case "*=":
                        return $"{operatorTypeName}.AsteriskEquals";
                    case "|":
                        return $"{operatorTypeName}.Bar";
                    case "||":
                        return $"{operatorTypeName}.BarBar";
                    case "|=":
                        return $"{operatorTypeName}.BarEquals";
                    case "^":
                        return $"{operatorTypeName}.Caret";
                    case "^=":
                        return $"{operatorTypeName}.CaretEquals";
                    case ":":
                        return $"{operatorTypeName}.Colon";
                    case "::":
                        return $"{operatorTypeName}.ColonColon";
                    case ":=":
                        return $"{operatorTypeName}.ColonEquals";
                    case ".":
                        return $"{operatorTypeName}.Dot";
                    case "=":
                        return $"{operatorTypeName}.Equals";
                    case "==":
                        return $"{operatorTypeName}.EqualsEquals";
                    case "=>":
                        return $"{operatorTypeName}.EqualsGreaterThan";
                    case "!":
                        return $"{operatorTypeName}.Exclamation";
                    case "!=":
                        return $"{operatorTypeName}.ExclamationEquals";
                    case ">":
                        return $"{operatorTypeName}.GreaterThan";
                    case ">=":
                        return $"{operatorTypeName}.GreaterThanEquals";
                    case ">>":
                        return $"{operatorTypeName}.GreaterThanGreaterThan";
                    case ">>>":
                        return $"{operatorTypeName}.GreaterThanGreaterThanGreaterThan";
                    case ">>=":
                        return $"{operatorTypeName}.GreaterThanGreaterThanEquals";
                    case ">>>=":
                        return $"{operatorTypeName}.GreaterThanGreaterThanGreaterThanEquals";
                    case "<":
                        return $"{operatorTypeName}.LessThan";
                    case "<=":
                        return $"{operatorTypeName}.LessThanEquals";
                    case "<>":
                        return $"{operatorTypeName}.LessThanGreaterThan";
                    case "<<":
                        return $"{operatorTypeName}.LessThanLessThan";
                    case "<<=":
                        return $"{operatorTypeName}.LessThanLessThanEquals";
                    case "-":
                        return $"{operatorTypeName}.Minus";
                    case "-=":
                        return $"{operatorTypeName}.MinusEquals";
                    case "->":
                        return $"{operatorTypeName}.MinusGreaterThan";
                    case "--":
                        return $"{operatorTypeName}.MinusMinus";
                    case "%":
                        return $"{operatorTypeName}.Percent";
                    case "%=":
                        return $"{operatorTypeName}.PercentEquals";
                    case "+":
                        return $"{operatorTypeName}.Plus";
                    case "+=":
                        return $"{operatorTypeName}.PlusEquals";
                    case "++":
                        return $"{operatorTypeName}.PlusPlus";
                    case "?":
                        return $"{operatorTypeName}.QuestionMark";
                    case "??=":
                        return $"{operatorTypeName}.QuestionQuestionEquals";
                    case "/":
                        return $"{operatorTypeName}.Slash";
                    case "/=":
                        return $"{operatorTypeName}.SlashEquals";
                    case "~":
                        return $"{operatorTypeName}.Tilde";
                }
 
                goto default;
 
            case "keyword - control":
                return $"ControlKeyword(\"{Text}\")";
 
            case "static symbol":
                return $"Static(\"{Text}\")";
 
            case "string - verbatim":
                return $"Verbatim(\"{Text}\")";
 
            case "string - escape character":
                return $"Escape(\"{Text}\")";
 
            default:
                var trimmedClassification = ClassificationName;
                if (trimmedClassification.EndsWith(" name"))
                {
                    trimmedClassification = trimmedClassification[..^" name".Length];
                }
 
                return $"{string.Join("", trimmedClassification.Split(' ').Select(Capitalize))}(\"{Text}\")";
        }
    }
 
    private static string Capitalize(string val)
        => char.ToUpperInvariant(val[0]) + val[1..];
}