using System;
using System.IO;
using System.Text.Json;
using Xunit;
using XplorePlane.Services.Configuration;

namespace XplorePlane.Tests.Services
{
    public sealed class CameraConfigServiceTests : IDisposable
    {
        private readonly string _tempDirectory;
        private readonly string _configPath;

        public CameraConfigServiceTests()
        {
            _tempDirectory = Path.Combine(
                Path.GetTempPath(),
                "XplorePlane.CameraConfig.Tests",
                Guid.NewGuid().ToString("N"));
            Directory.CreateDirectory(_tempDirectory);
            _configPath = Path.Combine(_tempDirectory, "config.json");
        }

        [Fact]
        public void Load_WhenFileDoesNotExist_ReturnsDefaultConfig()
        {
            var service = new CameraConfigService(_configPath);

            var config = service.Load();

            Assert.Equal(CameraConfig.Default.CameraType, config.CameraType);
            Assert.Equal(CameraConfig.Default.CameraSimulatedImagePath, config.CameraSimulatedImagePath);
        }

        [Fact]
        public void SaveAndLoad_PreservesOtherConfigurationFields()
        {
            File.WriteAllText(_configPath, """
                {
                  "ExistingSetting": 42,
                  "CameraType": "Hikvision"
                }
                """);
            var service = new CameraConfigService(_configPath);

            service.Save(new CameraConfig("Simulated", @"C:\images\sample.png"));
            var config = service.Load();

            Assert.Equal("Simulated", config.CameraType);
            Assert.Equal(@"C:\images\sample.png", config.CameraSimulatedImagePath);
            using var document = JsonDocument.Parse(File.ReadAllText(_configPath));
            Assert.Equal(42, document.RootElement.GetProperty("ExistingSetting").GetInt32());
        }

        public void Dispose()
        {
            if (Directory.Exists(_tempDirectory))
                Directory.Delete(_tempDirectory, recursive: true);
        }
    }
}