using CodePlay.Core.Interfaces;
using CodePlay.Core.Models;
using CodePlay.Core.Common;
using CodePlay.Core.Parsers;

namespace CodePlay.Core.Converters;

/// <summary>
/// C# 到 Java 代码转换器
/// </summary>
public class CSharpToJavaConverter : IConverter
{
    private readonly CSharpToJavaStrategy _strategy;
    private readonly ICodeGenerator _codeGenerator;
    
    public CSharpToJavaConverter()
    {
        _strategy = new CSharpToJavaStrategy();
        _codeGenerator = new JavaCodeGenerator();
    }
    
    /// <summary>
    /// 转换语法树
    /// </summary>
    public async Task<ConversionResult> ConvertAsync(
        Interfaces.SyntaxTree syntaxTree, 
        LanguageType targetLanguage, 
        ConversionOptions? options = null, 
        CancellationToken cancellationToken = default)
    {
        var result = new ConversionResult
        {
            Success = false,
            Warnings = new List<ConversionWarning>(),
            Report = new ConversionReport()
        };
        
        if (targetLanguage != LanguageType.Java)
        {
            result.ErrorMessage = "This converter only supports C# to Java conversion";
            return result;
        }
        
        try
        {
            var context = new ConversionContext
            {
                SourceLanguage = LanguageType.CSharp,
                TargetLanguage = LanguageType.Java,
                Options = options
            };
            
            // 转换根节点
            var convertedRoot = _strategy.ConvertNode(syntaxTree.Root, context);
            
            // 创建新的语法树
            var convertedTree = new Interfaces.SyntaxTree
            {
                Language = LanguageType.Java,
                Root = convertedRoot,
                SourceCode = syntaxTree.SourceCode
            };
            
            // 保留注释
            if (options?.KeepComments == true)
            {
                convertedTree.Documentation = syntaxTree.Documentation
                    .Select(d => new SyntaxDocumentation
                    {
                        ElementName = d.ElementName,
                        Content = ConvertDocumentation(d.Content),
                        Format = DocFormat.JavaDoc
                    }).ToList();
            }
            
            // 生成 Java 代码
            var generatedCode = _codeGenerator.Generate(convertedTree);
            
            result.TransformedCode = generatedCode;
            result.Success = true;
            
            // 生成报告
            if (result.Report != null)
            {
                result.Report.LinesConverted = syntaxTree.SourceCode?.Split('\n').Length ?? 0;
                result.Report.ClassesConverted = CountClasses(syntaxTree.Root);
                result.Report.MethodsConverted = CountMethods(syntaxTree.Root);
                result.Report.TodoItems = context.TodoItems;
                result.Report.Issues = context.Issues.Select(i => new IssueInfo { Description = i.Description, Severity = i.Severity, Line = i.Line, Suggestion = i.Suggestion }).ToList();
                result.Report.TransformationLog = context.Logs.Select(l => new TransformationLogEntry { Timestamp = l.Timestamp, Operation = l.Operation, Details = l.Details, Level = l.Level.ToString() }).ToList();
            }
            
            context.Logs.Add(new TransformationLog
            {
                Timestamp = DateTime.UtcNow,
                Operation = "Conversion",
                Details = "C# to Java conversion completed",
                Level = LogLevel.Info
            });
        }
        catch (Exception ex)
        {
            result.ErrorMessage = ex.Message;
            result.Success = false;
        }
        
        return await Task.FromResult(result);
    }
    
    private string ConvertDocumentation(string xmlDocContent)
    {
        // 简单的 XML Doc 到 JavaDoc 转换
        return xmlDocContent
            .Replace("///", " *")
            .Replace("<summary>", "")
            .Replace("</summary>", "")
            .Replace("<param name=", "@param ")
            .Replace("<returns>", "@return")
            .Replace("</returns>", "")
            .Replace("<exception cref=", "@throws ");
    }
    
    private int CountClasses(Interfaces.SyntaxNode node)
    {
        int count = 0;
        if (node.Type == SyntaxNodeType.Class) count++;
        count += node.Children.Sum(CountClasses);
        return count;
    }
    
    private int CountMethods(Interfaces.SyntaxNode node)
    {
        int count = 0;
        if (node.Type == SyntaxNodeType.Method) count++;
        count += node.Children.Sum(CountMethods);
        return count;
    }
}