using System.Reflection;

using FastReport;
using FastReport.Data.JsonConnection;
using FastReport.Export.Html;
using FastReport.Export.PdfSimple;

class Program
{
	static int Main(string[] args)
	{
		var options = ParseArgs(args);

		// --version
		if (options.ContainsKey("version"))
		{
			PrintVersion();
			return 0;
		}

		// --help o sin argumentos
		if (options.ContainsKey("help") || options.Count == 0)
		{
			PrintHelp();
			return 0;
		}

		// Validación de obligatorios
		if (!options.TryGetValue("template", out var frxPath) ||
			!options.TryGetValue("data", out var jsonPath) ||
			!options.TryGetValue("output", out var outputPath))
		{
			Console.Error.WriteLine("❌ Missing required arguments.\n");
			PrintHelp();
			return 1;
		}

		var format = options.TryGetValue("format", out var f)
			? f.ToLowerInvariant()
			: "pdf";

		try
		{
			// Leer JSON en memoria
			string jsonData = File.ReadAllText(jsonPath);

			// 2) Busca la conexión JSON ya definida
			var builder = new JsonDataSourceConnectionStringBuilder();
			builder.Json = jsonData;

			JsonDataSourceConnection jsonConn = new JsonDataSourceConnection();

			using var report = new Report();

			// Cargar el informe
			report.Load(frxPath);


			foreach (var conn in report.Dictionary.Connections)
			{
				Console.WriteLine($"Connection found: {conn.ToString()} ({conn.GetType().Name})");
				if (conn is JsonDataSourceConnection jdc)
				{
					jsonConn = jdc;
					break;
				}
			}

			if (jsonConn == null)
			{
				throw new Exception("No JSON data connection found in report.");
			}

				

			// 3) Cambia la cadena de conexión para usar el JSON real
			jsonConn.ConnectionString = builder.ToString();

			// 4) Crea las tablas internas basadas en ese JSON
			jsonConn.CreateAllTables();

			// 5) Preparar el reporte
			report.Prepare();

			if (format == "pdf")
			{
				// Exportar a PDF
				using var pdfExport = new PDFSimpleExport();
				using var fs = new FileStream(outputPath, FileMode.Create);
				pdfExport.Export(report, fs);
				Console.WriteLine($"Generated PDF: {outputPath}");
			}
			else
			{
				// Exportar a HTML
				using var htmlExport = new HTMLExport
				{
					EmbedPictures = true,
					SinglePage = true,
					SubFolder = false
				};
				using var fs = new FileStream(outputPath, FileMode.Create);
				report.Export(htmlExport, fs);
				Console.WriteLine($"Generated HTML: {outputPath}");
			}

			report.Dispose();

			return 0;
		}
		catch (Exception ex)
		{
			Console.Error.WriteLine("Error generating report: " + ex.Message);
			return 2;
		}
	}


	// ----------------------------
	// Helpers
	// ----------------------------

	static Dictionary<string, string> ParseArgs(string[] args)
	{
		var dict = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);

		foreach (var arg in args)
		{
			if (!arg.StartsWith("--"))
				continue;

			var parts = arg.Substring(2).Split('=', 2);

			if (parts.Length == 1)
				dict[parts[0]] = "true"; // flags: --help, --version
			else
				dict[parts[0]] = parts[1];
		}

		return dict;
	}

	static void PrintVersion()
	{
		var version = Assembly.GetExecutingAssembly().GetName().Version;
		Console.WriteLine();
		Console.WriteLine($"FastReportCliGenerator version {version}");
	}

	static void PrintHelp()
	{
		PrintVersion();
		Console.WriteLine(@"
Usage:
  FastReportCliGenerator \
    --template=<file.frx> \
    --data=<data.json> \
    --output=<output.html|pdf> \
    [--format=html|pdf]

Options:
  --template   Path to FRX template (required)
  --data       Path to JSON data file (required)
  --output     Output file path (required)
  --format     html or pdf (default)
  --version    Show version and exit
  --help       Show this help

Examples:
  FastReportCliGenerator \
    --template=invoice.frx \
    --data=invoice.json \
    --output=invoice.html

  FastReportCliGenerator \
    --template=invoice.frx \
    --data=invoice.json \
    --output=invoice.pdf \
    --format=pdf
");
	}
}