using System;
using System.IO;

namespace R0PatchGenerator
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("========================================");
            Console.WriteLine("  R0对战平台 增量包生成器");
            Console.WriteLine("========================================");
            Console.WriteLine();

            if (args.Length < 3)
            {
                PrintUsage();
                return;
            }

            string oldVersionPath = args[0];
            string newVersionPath = args[1];
            string outputPath = args[2];

            // 可选参数：版本号
            string fromVersion = args.Length > 3 ? args[3] : "unknown";
            string toVersion = args.Length > 4 ? args[4] : "unknown";

            Console.WriteLine("源版本目录: " + oldVersionPath);
            Console.WriteLine("目标版本目录: " + newVersionPath);
            Console.WriteLine("输出路径: " + outputPath);
            Console.WriteLine("从版本: " + fromVersion);
            Console.WriteLine("到版本: " + toVersion);
            Console.WriteLine();

            if (!Directory.Exists(oldVersionPath))
            {
                Console.WriteLine("错误: 源版本目录不存在!");
                return;
            }

            if (!Directory.Exists(newVersionPath))
            {
                Console.WriteLine("错误: 目标版本目录不存在!");
                return;
            }

            try
            {
                PatchGenerator generator = new PatchGenerator();
                bool success = generator.GeneratePatch(oldVersionPath, newVersionPath, outputPath, fromVersion, toVersion);
                
                if (success)
                {
                    Console.WriteLine();
                    Console.WriteLine("增量包生成成功!");
                    Console.WriteLine("输出文件: " + outputPath);

                    FileInfo fi = new FileInfo(outputPath);
                    Console.WriteLine("文件大小: " + FormatFileSize(fi.Length));
                }
                else
                {
                    Console.WriteLine();
                    Console.WriteLine("增量包生成失败!");
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine("错误: " + ex.Message);
                Console.WriteLine(ex.StackTrace);
            }
        }

        static void PrintUsage()
        {
            Console.WriteLine("用法:");
            Console.WriteLine("  R0PatchGenerator.exe <旧版本目录> <新版本目录> <输出文件.zip> [从版本] [到版本]");
            Console.WriteLine();
            Console.WriteLine("示例:");
            Console.WriteLine("  R0PatchGenerator.exe \"C:\\versions\\1.0.0\" \"C:\\versions\\1.0.1\" \"patch_1.0.0_to_1.0.1.zip\" 1.0.0 1.0.1");
            Console.WriteLine();
            Console.WriteLine("说明:");
            Console.WriteLine("  - 旧版本目录: 包含旧版本完整文件的目录");
            Console.WriteLine("  - 新版本目录: 包含新版本完整文件的目录");
            Console.WriteLine("  - 输出文件: 生成的增量包文件路径（.zip格式）");
            Console.WriteLine("  - 从版本/到版本: 可选，用于生成版本信息");
            Console.WriteLine();
            Console.WriteLine("增量包内容:");
            Console.WriteLine("  - patch.json: 更新清单文件");
            Console.WriteLine("  - patches/: 差异文件目录（使用HDiffPatch格式）");
            Console.WriteLine("  - new/: 新增文件目录");
            Console.WriteLine();
            Console.WriteLine("注意: 需要将 hdiffz.exe 放在同一目录下");
        }

        static string FormatFileSize(long bytes)
        {
            if (bytes >= 1073741824)
                return String.Format("{0:F2} GB", bytes / 1073741824.0);
            if (bytes >= 1048576)
                return String.Format("{0:F2} MB", bytes / 1048576.0);
            if (bytes >= 1024)
                return String.Format("{0:F2} KB", bytes / 1024.0);
            return String.Format("{0} B", bytes);
        }
    }
}