// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using System.Diagnostics;
using Microsoft.Extensions.Logging;
 
namespace Aspire.Cli.Git;
 
/// <summary>
/// Provides Git repository operations.
/// </summary>
/// <param name="executionContext">The CLI execution context providing the working directory.</param>
/// <param name="logger">The logger for diagnostic output.</param>
internal sealed class GitRepository(CliExecutionContext executionContext, ILogger<GitRepository> logger) : IGitRepository
{
    /// <inheritdoc />
    public async Task<DirectoryInfo?> GetRootAsync(CancellationToken cancellationToken)
    {
        logger.LogDebug("Searching for Git repository root from working directory: {WorkingDirectory}", executionContext.WorkingDirectory.FullName);
 
        try
        {
            var startInfo = new ProcessStartInfo("git", "rev-parse --show-toplevel")
            {
                WorkingDirectory = executionContext.WorkingDirectory.FullName,
                RedirectStandardOutput = true,
                RedirectStandardError = true,
                UseShellExecute = false,
                CreateNoWindow = true
            };
 
            using var process = new Process { StartInfo = startInfo };
 
            process.Start();
 
            var outputTask = process.StandardOutput.ReadToEndAsync(cancellationToken);
            var errorTask = process.StandardError.ReadToEndAsync(cancellationToken);
 
            await process.WaitForExitAsync(cancellationToken).ConfigureAwait(false);
 
            if (process.ExitCode != 0)
            {
                var errorOutput = await errorTask.ConfigureAwait(false);
                logger.LogDebug("Git command returned non-zero exit code {ExitCode}: {Error}", process.ExitCode, errorOutput.Trim());
                return null;
            }
 
            var output = await outputTask.ConfigureAwait(false);
            var rootPath = output.Trim();
 
            if (string.IsNullOrEmpty(rootPath))
            {
                logger.LogDebug("Git command returned empty output");
                return null;
            }
 
            var directoryInfo = new DirectoryInfo(rootPath);
            if (directoryInfo.Exists)
            {
                logger.LogDebug("Found Git repository root: {GitRoot}", directoryInfo.FullName);
                return directoryInfo;
            }
 
            logger.LogDebug("Git repository root path does not exist: {GitRoot}", rootPath);
            return null;
        }
        catch (Exception ex) when (ex is InvalidOperationException or System.ComponentModel.Win32Exception)
        {
            logger.LogDebug(ex, "Git is not installed or not found in PATH");
            return null;
        }
    }
}