Initial implementation of wrapper CLI

This still has several flaws:
- completely untested on Windows
- Standalone doesn't work on macOS either
- uses CPM to get fmt when we already vendor it, cause otherwise the program doesn't link
- all the metadata going into AU needs to be removed once it's read from the CLAP. This should happen before this gets merged

Needs to be discussed:
- replace OS APIs with std::filesystem at the expense of bumping min macOS version to 10.15?

CMakeLists.txt

@@ -151,3 +151,5 @@ endif()
 if (${CLAP_WRAPPER_BUILD_TESTS})
     add_subdirectory(tests)
 endif()
+
+add_subdirectory(cli)

cli/CMakeLists.txt

@@ -0,0 +1,20 @@
+add_executable(clap-wrapper-cli
+        src/main.cpp
+)
+
+CPMAddPackage(NAME CL11
+        GITHUB_REPOSITORY CLIUtils/CLI11
+        GIT_TAG v2.4.2)
+
+# TODO: deduplicate this with the vendored fmt -
+#       for some reason, the cli won't link
+#       if we include the vendored version
+CPMAddPackage(
+        NAME fmt
+        GITHUB_REPOSITORY fmtlib/fmt
+        GIT_TAG 11.0.2
+        OPTIONS
+        "FMT_INSTALL ON"
+)
+
+target_link_libraries(clap-wrapper-cli PUBLIC CLI11::CLI11 fmt::fmt)

cli/src/main.cpp

@@ -0,0 +1,267 @@
+#include <iostream>
+#include <string>
+#include <fstream>
+#include <stdexcept>
+#include <CLI/CLI.hpp>
+#include <fmt/format.h>
+
+// rationale against using std::filesystem is that
+// it requires macOS 10.15, but our min supported version is 10.13 atm
+#ifdef _WIN32
+#include <direct.h>
+#define CREATE_DIRECTORY(dir) _mkdir(dir)
+#define DIRECTORY_EXISTS (errno == EEXIST)
+#define PATH_SEPARATOR "\\"
+#define GET_CURRENT_DIR _getcwd
+#else
+#include <sys/stat.h>
+#include <unistd.h>
+#define CREATE_DIRECTORY(dir) mkdir(dir, 0777)
+#define DIRECTORY_EXISTS (errno == EEXIST)
+#define PATH_SEPARATOR "/"
+#define GET_CURRENT_DIR getcwd
+#endif
+
+std::string get_absolute_path(const std::string& path)
+{
+  if (path.empty())
+  {
+    return "";
+  }
+
+  if (path[0] == '/' || (path.length() > 1 && path[1] == ':'))
+  {
+    // Path is already absolute
+    return path;
+  }
+
+  char current_dir[1024];
+  if (GET_CURRENT_DIR(current_dir, sizeof(current_dir)) == nullptr)
+  {
+    throw std::runtime_error("Failed to get current directory");
+  }
+
+  return std::string(current_dir) + PATH_SEPARATOR + path;
+}
+
+/**
+ * Creates a directory if it doesn't exist.
+ * @param path Path of the directory to create.
+ */
+void create_directory(const std::string& path)
+{
+  if (CREATE_DIRECTORY(path.c_str()) != 0)
+  {
+    if (!DIRECTORY_EXISTS)
+    {
+      throw std::runtime_error("Failed to create directory: " + path +
+                               " Error: " + std::strerror(errno));
+    }
+  }
+}
+
+void write_cmakelists(const std::string& output_dir)
+{
+  std::string cmake_path = output_dir + "/CMakeLists.txt";
+  std::ofstream cmake_file(cmake_path);
+  if (!cmake_file)
+  {
+    throw std::runtime_error("Failed to create CMakeLists.txt");
+  }
+
+  const char* cmake_content = R"(
+cmake_minimum_required(VERSION 3.15)
+project(${PROJECT_NAME})
+
+set(CMAKE_CXX_STANDARD 17)
+if (APPLE)
+  enable_language(OBJC)
+  enable_language(OBJCXX)
+endif()
+
+# Download CPM.cmake
+file(
+  DOWNLOAD
+  https://github.com/cpm-cmake/CPM.cmake/releases/download/v0.40.2/CPM.cmake
+  ${CMAKE_CURRENT_BINARY_DIR}/cmake/CPM.cmake
+  EXPECTED_HASH SHA256=C8CDC32C03816538CE22781ED72964DC864B2A34A310D3B7104812A5CA2D835D
+)
+include(${CMAKE_CURRENT_BINARY_DIR}/cmake/CPM.cmake)
+
+# Add clap-wrapper as a dependency
+set(CLAP_WRAPPER_DOWNLOAD_DEPENDENCIES ON)
+CPMAddPackage(
+  NAME clap-wrapper
+  GITHUB_REPOSITORY free-audio/clap-wrapper
+  GIT_TAG main
+)
+
+if(BUILD_AU)
+  set(AUV2_TARGET ${PROJECT_NAME}_auv2)
+  add_library(${AUV2_TARGET} MODULE)
+  target_add_auv2_wrapper(
+      TARGET ${AUV2_TARGET}
+      MACOS_EMBEDDED_CLAP_LOCATION ${CLAP_PLUGIN_PATH}
+
+      # TODO: remove all the below once baconpaul reads it from the CLAP
+      OUTPUT_NAME "${PROJECT_NAME}"
+      BUNDLE_IDENTIFIER "com.yourcompany.${PROJECT_NAME}clap"
+      BUNDLE_VERSION "1.0"
+      MANUFACTURER_NAME "Your Company"
+      MANUFACTURER_CODE "YuCu"
+      SUBTYPE_CODE "${AU_SUBTYPE_CODE}"
+      INSTRUMENT_TYPE "aufx"
+  )
+
+  add_custom_command(TARGET ${AUV2_TARGET} POST_BUILD
+      COMMAND ${CMAKE_COMMAND} -E copy_directory
+          $<TARGET_BUNDLE_DIR:${AUV2_TARGET}>
+          "${OUTPUT_DIR}/${PROJECT_NAME}.component"
+  )
+endif()
+
+if(BUILD_VST3)
+  set(VST3_TARGET ${PROJECT_NAME}_vst3)
+  add_library(${VST3_TARGET} MODULE)
+  target_add_vst3_wrapper(
+      TARGET ${VST3_TARGET}
+      MACOS_EMBEDDED_CLAP_LOCATION ${CLAP_PLUGIN_PATH}
+      WINDOWS_FOLDER_VST3 ON
+      OUTPUT_NAME "${PROJECT_NAME}"
+  )
+
+  add_custom_command(TARGET ${VST3_TARGET} POST_BUILD
+      COMMAND ${CMAKE_COMMAND} -E copy_directory
+          $<TARGET_BUNDLE_DIR:${VST3_TARGET}>
+          "${OUTPUT_DIR}/${PROJECT_NAME}.vst3"
+  )
+endif()
+
+if(BUILD_STANDALONE)
+  set(STANDALONE_TARGET ${PROJECT_NAME}_standalone)
+  add_executable(${STANDALONE_TARGET})
+  target_add_standalone_wrapper(
+      TARGET ${STANDALONE_TARGET}
+      MACOS_EMBEDDED_CLAP_LOCATION ${CLAP_PLUGIN_PATH}
+      OUTPUT_NAME "${PROJECT_NAME}"
+  )
+
+  if(APPLE)
+    set_target_properties(${STANDALONE_TARGET} PROPERTIES
+        MACOSX_BUNDLE TRUE
+        MACOSX_BUNDLE_GUI_IDENTIFIER "com.yourcompany.${PROJECT_NAME}standalone"
+        MACOSX_BUNDLE_BUNDLE_NAME "${PROJECT_NAME}"
+    )
+    add_custom_command(TARGET ${STANDALONE_TARGET} POST_BUILD
+        COMMAND ${CMAKE_COMMAND} -E copy_directory
+            $<TARGET_BUNDLE_DIR:${STANDALONE_TARGET}>
+            "${OUTPUT_DIR}/${PROJECT_NAME}.app"
+    )
+  elseif(WIN32)
+    add_custom_command(TARGET ${STANDALONE_TARGET} POST_BUILD
+        COMMAND ${CMAKE_COMMAND} -E copy
+            $<TARGET_FILE:${STANDALONE_TARGET}>
+            "${OUTPUT_DIR}/${PROJECT_NAME}.exe"
+    )
+  else()
+    add_custom_command(TARGET ${STANDALONE_TARGET} POST_BUILD
+        COMMAND ${CMAKE_COMMAND} -E copy
+            $<TARGET_FILE:${STANDALONE_TARGET}>
+            "${OUTPUT_DIR}/${PROJECT_NAME}"
+    )
+  endif()
+endif()
+)";
+
+  cmake_file << cmake_content;
+  cmake_file.close();
+}
+
+int main(int argc, char** argv)
+{
+  CLI::App app{"CLAP Wrapper CLI"};
+
+  std::string input_path;
+  std::string output_dir = ".";
+  std::string build_dir = "";
+  bool build_au = false;
+  bool build_vst3 = false;
+  bool build_standalone = false;
+
+  app.add_option("-i,--input", input_path, "Input .clap file or directory")->required();
+  app.add_option("-o,--outputDir", output_dir, "Output directory");
+  app.add_option("-b,--buildDir", build_dir, "Build directory for CMake");
+  app.add_flag("--au", build_au, "Build Audio Unit wrapper");
+  app.add_flag("--vst3", build_vst3, "Build VST3 wrapper");
+  app.add_flag("--standalone", build_standalone, "Build standalone application");
+
+  CLI11_PARSE(app, argc, argv);
+
+  if (!build_au && !build_vst3 && !build_standalone)
+  {
+    throw std::runtime_error("At least one output format must be specified");
+  }
+
+
+  // resolve paths to absolute
+  input_path = get_absolute_path(input_path);
+  output_dir = get_absolute_path(output_dir);
+
+  if (build_dir.empty())
+  {
+    // default to adding a build dir in the working directory
+    build_dir = get_absolute_path("wrap-build");
+  }
+  else
+  {
+    build_dir = get_absolute_path(build_dir);
+  }
+
+  try
+  {
+    // create the output directory if it doesn't exist
+    create_directory(output_dir);
+
+    // create build directory
+    create_directory(build_dir);
+
+    // write CMakeLists.txt
+    write_cmakelists(build_dir);
+
+    // extract project name from input path
+    std::string::size_type pos = input_path.find_last_of("/\\");
+    std::string clap_filename = (pos == std::string::npos) ? input_path : input_path.substr(pos + 1);
+    std::string project_name = clap_filename.substr(0, clap_filename.find_last_of('.'));
+
+    // construct cmake command with variables supplied
+    std::string cmake_cmd = fmt::format(
+        "cmake . "
+        "-DPROJECT_NAME=\"{}\" "
+        "-DCLAP_PLUGIN_PATH=\"{}\" "
+        "-DOUTPUT_DIR=\"{}\" "
+        "-DBUILD_AU={} "
+        "-DBUILD_VST3={} "
+        "-DBUILD_STANDALONE={} "
+        "-DAU_SUBTYPE_CODE=\"{}\"",
+        project_name, input_path, output_dir, build_au ? "ON" : "OFF", build_vst3 ? "ON" : "OFF",
+        build_standalone ? "ON" : "OFF", project_name.substr(0, 4));
+
+    // run CMake
+    cmake_cmd = fmt::format("cd \"{}\" && {} && cmake --build . --config Release", build_dir, cmake_cmd);
+
+    int result = std::system(cmake_cmd.c_str());
+    if (result != 0)
+    {
+      throw std::runtime_error("CMake build failed");
+    }
+
+    std::cout << "Wrapping completed successfully. Output files are in: " << output_dir << std::endl;
+  }
+  catch (const std::exception& e)
+  {
+    std::cerr << "Error during wrapping: " << e.what() << std::endl;
+    return 1;
+  }
+
+  return 0;
+}