using System;
using System.IO;
using Xunit;

namespace GitConverter.TestsApp.ConsoleApp
{
    /// <summary>
    /// Tests for logging configuration in Program.cs. 
    /// Validates that logging initialization handles various edge cases gracefully.
    /// </summary>
    [Collection("Logging")]
    public class LoggingTests : IDisposable
    {
        private readonly TextWriter _originalOut;
        private readonly TextWriter _originalErr;
        private readonly StringWriter _outWriter;
        private readonly StringWriter _errWriter;
        private readonly string _tempRoot;

        public LoggingTests()
        {
            _originalOut = Console.Out;
            _originalErr = Console.Error;
            _outWriter = new StringWriter();
            _errWriter = new StringWriter();
            Console.SetOut(_outWriter);
            Console.SetError(_errWriter);

            _tempRoot = Path.Combine(Path.GetTempPath(), "GitConverter.LogTests", Guid.NewGuid().ToString("N"));
            Directory.CreateDirectory(_tempRoot);
        }

        public void Dispose()
        {
            Console.SetOut(_originalOut);
            Console.SetError(_originalErr);
            _outWriter.Dispose();
            _errWriter.Dispose();
            try { if (Directory.Exists(_tempRoot)) Directory.Delete(_tempRoot, true); } catch { }
        }

        [Fact(DisplayName = "Logging with valid path and level creates log file")]
        public void Run_WithValidLogPath_CreatesLogFile()
        {
            var dummyInput = Path.Combine(_tempRoot, "dummy.csv");
            File.WriteAllText(dummyInput, "x,y\n1,2");

            var logPath = Path.Combine(_tempRoot, "test.log");
            var outDir = Path.Combine(_tempRoot, "out");
            var tempDir = Path.Combine(_tempRoot, "temp");

            var args = new[]
            {
                "gis_convert",
                dummyInput,
                "Csv",
                outDir,
                tempDir,
                "Log",
                logPath,
                "DEBUG"
            };

            var exit = GitConverter.ConsoleApp.Program.Run(args);

            Assert.True(File.Exists(logPath) || _errWriter.ToString().Contains("warning: logging disabled"),
                $"Expected log file at {logPath} or a warning about logging failure");
        }

        [Fact(DisplayName = "Logging with invalid path prints warning to stderr")]
        public void Run_WithInvalidLogPath_PrintsWarningToStderr()
        {
            var dummyInput = Path.Combine(_tempRoot, "dummy.csv");
            File.WriteAllText(dummyInput, "x,y\n1,2");

            var invalidLogPath = Path.Combine(_tempRoot, "nonexistent", "subdir", "test.log");
            var outDir = Path.Combine(_tempRoot, "out");
            var tempDir = Path.Combine(_tempRoot, "temp");

            var args = new[]
            {
                "gis_convert",
                dummyInput,
                "Csv",
                outDir,
                tempDir,
                "Log",
                invalidLogPath
            };

            _errWriter.GetStringBuilder().Clear();
            var exit = GitConverter.ConsoleApp.Program.Run(args);

            var stderr = _errWriter.ToString();
            Assert.Contains("warning: logging disabled", stderr.ToLowerInvariant());
        }

        [Fact(DisplayName = "Logging without Log keyword ignores subsequent tokens")]
        public void Run_WithoutLogKeyword_IgnoresLogPath()
        {
            var dummyInput = Path.Combine(_tempRoot, "dummy.csv");
            File.WriteAllText(dummyInput, "x,y\n1,2");

            var outDir = Path.Combine(_tempRoot, "out");
            var tempDir = Path.Combine(_tempRoot, "temp");

            var args = new[]
            {
                "gis_convert",
                dummyInput,
                "Csv",
                outDir,
                tempDir,
                "some_random_token",
                "random_path.log"
            };

            var exit = GitConverter.ConsoleApp.Program.Run(args);

            var stderr = _errWriter.ToString();
            Assert.DoesNotContain("warning: logging disabled", stderr.ToLowerInvariant());
        }

        [Fact(DisplayName = "Log level parsing is case-insensitive")]
        public void Run_LogLevelCaseInsensitive_AcceptsAnyCase()
        {
            var dummyInput = Path.Combine(_tempRoot, "dummy.csv");
            File.WriteAllText(dummyInput, "x,y\n1,2");

            var logPath = Path.Combine(_tempRoot, "test_case.log");
            var outDir = Path.Combine(_tempRoot, "out");
            var tempDir = Path.Combine(_tempRoot, "temp");

            var args = new[]
            {
                "gis_convert",
                dummyInput,
                "Csv",
                outDir,
                tempDir,
                "Log",
                logPath,
                "debug"
            };

            var exit = GitConverter.ConsoleApp.Program.Run(args);

            var stderr = _errWriter.ToString();
            Assert.DoesNotContain("unknown", stderr.ToLowerInvariant());
        }

        [Fact(DisplayName = "Log path with spaces is parsed correctly")]
        public void Run_LogPathWithSpaces_ParsedCorrectly()
        {
            var dummyInput = Path.Combine(_tempRoot, "dummy.csv");
            File.WriteAllText(dummyInput, "x,y\n1,2");

            var logDir = Path.Combine(_tempRoot, "log folder with spaces");
            Directory.CreateDirectory(logDir);
            var logPath = Path.Combine(logDir, "test.log");
            
            var outDir = Path.Combine(_tempRoot, "out");
            var tempDir = Path.Combine(_tempRoot, "temp");

            var args = new[]
            {
                "gis_convert",
                dummyInput,
                "Csv",
                outDir,
                tempDir,
                "Log",
                logPath,
                "INFO"
            };

            var exit = GitConverter.ConsoleApp.Program.Run(args);

            Assert.True(File.Exists(logPath) || _errWriter.ToString().Contains("warning"),
                "Expected log file to be created when path contains spaces");
        }
    }
}