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cli/README.md

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+# clap-wrapper CLI
+
+A command-line tool to wrap CLAP plugins into other plugin formats.
+
+At the moment, only thick wrappers for AUv2 and VST3 are supported.  
+These thick wrappers bundle the CLAP plugin inside them, so they don't require the CLAP plugin to be installed on the
+user's machine additionally.
+
+Support for thin wrappers (i.e. plugins that don't contain the CLAP and load it from the user's file system),
+as well as support for Standalone wrapping (which can only be implemented using thin wrapping on Windows and Linux) is
+planned.
+
+## Prerequisites
+
+Before using clap-wrapper CLI, ensure you have the following installed on your system:
+
+- CMake (version 3.15 or higher)
+
+## Usage
+
+The general usage of clap-wrapper CLI follows the pattern:
+
+```
+clap-wrapper-cli [options]
+```
+
+### Options
+
+| Option                                  | Description                               | Default                                                   |
+|-----------------------------------------|-------------------------------------------|-----------------------------------------------------------|
+| `-i, --input <path>`                    | Path to the input .clap file or directory | (Required)                                                |
+| `-o, --output_dir <path>`               | Output directory for wrapped plugins      | Current working directory                                 |
+| `-b, --build_dir <path>`                | Build directory for CMake                 | `wrap-build` in current working directory                 |
+| `--au`                                  | Build Audio Unit wrapper                  | Off                                                       |
+| `--vst3`                                | Build VST3 wrapper                        | Off                                                       |
+| `--au_manufacturer_code <code>`         | AU manufacturer code (4 letters)          | Read from `clap_plugin_info_as_auv2` extension if present |
+| `--au_manufacturer_name <name>`         | AU manufacturer display name              | Read from `clap_plugin_info_as_auv2` extension if present |
+| `-r, --clap_wrapper_github_repo <repo>` | GitHub repository for clap-wrapper        | "free-audio/clap-wrapper"                                 |
+| `-t, --clap_wrapper_git_tag <tag>`      | Git tag or branch for clap-wrapper        | "main"                                                    |
+| `--cmake <path>`                        | Path to CMake binary to use for wrapping  | "cmake"                                                   |
+
+Note: At least one of `--au` or `--vst3` must be specified.
+
+The AU manufacturer code and name are read from the CLAP plugin's `clap_plugin_info_as_auv2` extension if it's
+implemented. If the extension is not present, the CLI options `--au_manufacturer_code` and `--au_manufacturer_name`
+become mandatory for AU wrapping.
+
+Example usage:
+
+```shell
+clap-wrapper-cli -i /path/to/my/plugin.clap -o /output/directory --vst3 --au --au_manufacturer_code Abcd --au_manufacturer_name "My Company"
+```
+
+This command will wrap the CLAP plugin located at `/path/to/my/plugin.clap` into both VST3 and AU formats, placing the
+output in `/output/directory`. If the plugin implements the `clap_plugin_info_as_auv2` extension, the manufacturer code
+and name from the extension will be used unless overridden by the CLI options.
+
+## AU Wrapping
+
+Audio Unit (AU) wrapping is only supported on macOS.  
+When wrapping a CLAP plugin as an AU, information about the plugin
+manufacturer needs to be supplied.
+
+The clap-wrapper CLI handles manufacturer information as follows:
+
+- Command-line options:
+    - You can provide the manufacturer information using the `--au_manufacturer_code` and `--au_manufacturer_name`
+      options.
+    - The manufacturer code must be exactly 4 characters long, starting with an uppercase letter followed by lowercase
+      letters and/or numbers.
+    - If provided, these values will be used for the AU wrapper, regardless of whether the CLAP plugin implements the
+      `clap_plugin_info_as_auv2` extension.
+
+- The `clap_plugin_info_as_auv2` extension in the CLAP plugin:
+    - If the CLAP plugin implements this extension, it can provide the manufacturer code and name directly from the
+      plugin.
+    - These values will be used only if the corresponding command-line options are not provided.
+
+- If neither the command-line options nor the `clap_plugin_info_as_auv2` extension provide the manufacturer information,
+  the AU wrapping process will fail.
+
+Implementing the `clap_plugin_info_as_auv2` extension is recommended to provide default manufacturer information.
+This ensures that users can wrap the plugin as an AU without needing to specify the manufacturer details manually,
+but still allows for overriding if needed.
+
+## Installation
+
+Currently, there are no pre-built binaries available for download.
+To use clap-wrapper CLI, you'll need to build it from source.
+
+## Building from Source
+
+To compile this project yourself, follow these steps:
+
+1. Clone the repository:
+   ```
+   git clone https://github.com/free-audio/clap-wrapper.git
+   cd clap-wrapper
+   ```
+
+2. Create a build directory and navigate to it:
+   ```
+   mkdir build
+   cd build
+   ```
+
+3. Run CMake to configure the project and build the CLI:
+   ```
+   cmake ..
+   cmake --build . --target clap-wrapper-cli
+   ```
+
+After successful compilation, you should have the `clap-wrapper-cli` executable in the `cli` subfolder of your build
+directory.