📝 Chore: Add README

README.md

@@ -0,0 +1,140 @@
+# Git Identity Manager
+
+Git Identity Manager is a command-line tool written in Rust that helps you
+manage multiple Git identities for your repositories. It allows you to add new
+identities, view stored identities, and apply an identity to the local Git
+repository (without affecting your global configuration).
+
+## Overview
+
+Git Identity Manager stores your Git identities (name and email) in a
+human-readable TOML configuration file located in an OS-appropriate directory:
+
+- **Linux/Unix:** `$XDG_CONFIG_HOME/git_identity_manager/git_identities.toml`
+  (or defaults to `$HOME/.config/git_identity_manager/git_identities.toml`)
+- **macOS:** `$HOME/Library/Application
+Support/git_identity_manager/git_identities.toml`
+- **Windows:** `%APPDATA%\git_identity_manager\git_identities.toml`
+
+When you run the tool inside a Git repository, it presents an interactive menu
+that allows you to:
+
+- **Select an Existing Identity:** Choose from a list of saved identities to
+  apply locally.
+- **Add a New Identity:** Input a new Git name and email. The name is used as
+  the display name, while a sanitized version (spaces replaced with underscores)
+  is used as the key in the configuration file.
+- **Quit:** Exit the program without making any changes.
+
+Once an identity is applied, the tool sets the local Git configuration (i.e.,
+`git config user.name` and `git config user.email`), overwriting any existing
+local settings.
+
+## Installation
+
+### Prerequisites
+
+- [Rust](https://www.rust-lang.org/tools/install) (latest stable release is
+  recommended)
+- A Git repository (to test local Git identity settings)
+
+### Build and Install
+
+1. **Clone the Repository:**
+
+   ```bash
+   git clone https://git.musselman.dev/Musselman/git-identity-manager
+   cd git-identity-manager
+   ```
+
+2. **Build the Project:**
+
+   Use Cargo to build the project:
+
+   `bash cargo build --release`
+
+   The compiled binary will be available in the `target/release` directory.
+
+3. **(Optional) Install the Binary:**
+
+   You can install the binary to your system (if you have Cargo's bin directory
+   in your PATH):
+
+   `bash cargo install --path .`
+
+## Usage
+
+Run the tool from within a Git repository directory using the appropriate binary:
+
+`./git-identity-manager` or `git-identity-manager.exe`
+
+Upon running, you will see a menu similar to this:
+
+```bash
+=== Git Identity Manager ===
+
+Available identities:
+1. James_Musselman: James Musselman <email@example.com>
+
+Options: [number] - Select and set that identity
+          a        - Add a new identity
+          q        - Quit
+
+Enter your choice:
+```
+
+### Options
+
+- **Selecting an Identity:** Enter the corresponding number to apply the
+  identity. The tool will run:
+
+  ```bash
+  git config user.name "James Musselman"
+  git config user.email "email@example.com"
+  ```
+
+  _Note:_ These commands will update your local repository's Git configuration.
+
+- **Adding a New Identity:** Type `a` and follow the prompts to enter a Git
+  name and email address.
+
+  - **Key Sanitization:** If your Git name contains spaces (e.g., "James
+    Musselman"), spaces will be replaced with underscores when saving as a key,
+    but the display and applied identity remain unchanged.
+  - After adding, the new identity is saved to the configuration file and
+    immediately applied locally.
+
+- **Quitting:** Enter `q` to exit without making any changes.
+
+## Configuration File
+
+The identities are stored in a TOML file in an OS-appropriate directory. A
+sample configuration file may look like:
+
+```toml
+[identities.James_Musselman]
+name  = "James Musselman"
+email = "email@example.com"
+
+[identities.Jane_Doe]
+name  = "Jane Doe"
+email = "jane.doe@example.com"
+```
+
+Each identity is stored under a key where spaces in the Git name are replaced
+with underscores.
+
+## Overwriting Behavior
+
+When applying an identity, the tool uses `git config` (without the `--global`
+flag) to set the identity in the local repository configuration. This will
+overwrite any existing local Git identity settings.
+
+## Contributing
+
+Contributions are welcome! Please fork the repository and submit a pull request
+with your changes.
+
+## License
+
+This project is licensed under the [MIT License](LICENSE).