using System.Diagnostics;

namespace CodePlay.Core.Services;

/// <summary>
/// 代码格式化服务
/// 支持 C#/Java/C++ 代码格式化
/// </summary>
public interface ICodeFormatter
{
    Task<string> FormatAsync(string code, string language, CancellationToken cancellationToken = default);
    bool IsFormatterAvailable(string language);
}

public class CodeFormatter : ICodeFormatter
{
    public async Task<string> FormatAsync(string code, string language, CancellationToken cancellationToken = default)
    {
        return language.ToLower() switch
        {
            "csharp" => await FormatCSharp(code, cancellationToken),
            "java" => await FormatJava(code, cancellationToken),
            "cpp" or "c++" => await FormatCpp(code, cancellationToken),
            _ => code
        };
    }

    public bool IsFormatterAvailable(string language)
    {
        return language.ToLower() switch
        {
            "csharp" => IsDotNetFormatAvailable(),
            "java" => IsJavaFormatAvailable(),
            "cpp" or "c++" => IsClangFormatAvailable(),
            _ => false
        };
    }

    private async Task<string> FormatCSharp(string code, CancellationToken ct)
    {
        if (!IsDotNetFormatAvailable())
            return code;

        try
        {
            var tempFile = Path.GetTempFileName() + ".cs";
            await File.WriteAllTextAsync(tempFile, code, ct);

            var startInfo = new ProcessStartInfo
            {
                FileName = "dotnet",
                Arguments = $"format \"{tempFile}\" --no-restore",
                RedirectStandardOutput = true,
                RedirectStandardError = true,
                UseShellExecute = false,
                CreateNoWindow = true
            };

            using var process = Process.Start(startInfo);
            if (process == null) return code;

            await process.WaitForExitAsync(ct);

            if (process.ExitCode == 0)
                return await File.ReadAllTextAsync(tempFile, ct);

            return code;
        }
        catch
        {
            return code;
        }
    }

    private async Task<string> FormatJava(string code, CancellationToken ct)
    {
        if (!IsJavaFormatAvailable())
            return code;

        try
        {
            var tempFile = Path.GetTempFileName() + ".java";
            await File.WriteAllTextAsync(tempFile, code, ct);

            var startInfo = new ProcessStartInfo
            {
                FileName = "google-java-format",
                Arguments = $"--replace \"{tempFile}\"",
                RedirectStandardOutput = true,
                RedirectStandardError = true,
                UseShellExecute = false,
                CreateNoWindow = true
            };

            using var process = Process.Start(startInfo);
            if (process == null) return code;

            await process.WaitForExitAsync(ct);

            if (process.ExitCode == 0)
                return await File.ReadAllTextAsync(tempFile, ct);

            return code;
        }
        catch
        {
            return code;
        }
    }

    private async Task<string> FormatCpp(string code, CancellationToken ct)
    {
        if (!IsClangFormatAvailable())
            return code;

        try
        {
            var tempFile = Path.GetTempFileName() + ".cpp";
            await File.WriteAllTextAsync(tempFile, code, ct);

            var startInfo = new ProcessStartInfo
            {
                FileName = "clang-format",
                Arguments = $"-i -style=file \"{tempFile}\"",
                RedirectStandardOutput = true,
                RedirectStandardError = true,
                UseShellExecute = false,
                CreateNoWindow = true
            };

            using var process = Process.Start(startInfo);
            if (process == null) return code;

            await process.WaitForExitAsync(ct);

            if (process.ExitCode == 0)
                return await File.ReadAllTextAsync(tempFile, ct);

            return code;
        }
        catch
        {
            return code;
        }
    }

    private bool IsDotNetFormatAvailable()
    {
        try
        {
            var startInfo = new ProcessStartInfo
            {
                FileName = "dotnet",
                Arguments = "tool list -g",
                RedirectStandardOutput = true,
                UseShellExecute = false,
                CreateNoWindow = true
            };

            using var process = Process.Start(startInfo);
            process?.WaitForExit(5000);
            var output = process?.StandardOutput.ReadToEnd();
            return output?.Contains("dotnet-format") == true;
        }
        catch
        {
            return false;
        }
    }

    private bool IsJavaFormatAvailable()
    {
        try
        {
            var startInfo = new ProcessStartInfo
            {
                FileName = "google-java-format",
                Arguments = "--version",
                RedirectStandardOutput = true,
                UseShellExecute = false,
                CreateNoWindow = true
            };

            using var process = Process.Start(startInfo);
            process?.WaitForExit(5000);
            return process?.ExitCode == 0;
        }
        catch
        {
            return false;
        }
    }

    private bool IsClangFormatAvailable()
    {
        try
        {
            var startInfo = new ProcessStartInfo
            {
                FileName = "clang-format",
                Arguments = "--version",
                RedirectStandardOutput = true,
                UseShellExecute = false,
                CreateNoWindow = true
            };

            using var process = Process.Start(startInfo);
            process?.WaitForExit(5000);
            return process?.ExitCode == 0;
        }
        catch
        {
            return false;
        }
    }
}