#!/bin/bash

# Save the original working directory
ORIGINAL_DIR="$(pwd)"

# Function to detect the operating system
detect_os() {
    if [[ "$OSTYPE" == "darwin"* ]]; then
        echo "macos"
    elif [[ -f /etc/os-release ]]; then
        . /etc/os-release
        echo "$ID"
    else
        echo "unknown"
    fi
}

# Install fnm (Fast Node Manager) if it is not already installed
if command -v fnm &> /dev/null; then
    echo -e "fnm is already installed\n"
    fnm --version
else
    echo -e "Installing fnm (Fast Node Manager)\n"
    
    os=$(detect_os)
    
    case $os in
        macos)
            # Try homebrew first on macOS
            if command -v brew &> /dev/null; then
                echo "Installing fnm via Homebrew..."
                brew install fnm
            else
                echo "Installing fnm via official installer..."
                curl -fsSL https://git.miomio.moe/mio/easyzsh/raw/branch/master/install/fnm.sh | bash
            fi
            ;;
        ubuntu|debian)
            # Use the official installer for Linux
            echo "Installing fnm via official installer..."
            curl -fsSL https://git.miomio.moe/mio/easyzsh/raw/branch/master/install/fnm.sh | bash
            ;;
        fedora|centos|rhel)
            # Use the official installer for RHEL-based distros
            echo "Installing fnm via official installer..."
            curl -fsSL https://git.miomio.moe/mio/easyzsh/raw/branch/master/install/fnm.sh | bash
            ;;
        arch|manjaro)
            # Use the official installer for Arch-based distros
            echo "Installing fnm via official installer..."
            curl -fsSL https://git.miomio.moe/mio/easyzsh/raw/branch/master/install/fnm.sh | bash
            ;;
        *)
            echo "Using official installer for unknown OS..."
            curl -fsSL https://git.miomio.moe/mio/easyzsh/raw/branch/master/install/fnm.sh | bash
            ;;
    esac

    # Load fnm for the remainder of this script
    export PATH="$HOME/.local/share/fnm:$PATH"
    eval "$(fnm env --use-on-cd)"
fi

# OPTIONAL: Install the latest LTS version of Node.js
# Uncomment the following lines if you would like to automatically install it
# echo "Installing latest LTS Node.js version..."
# fnm install --lts
# fnm use lts-latest
# fnm default lts-latest

# Apply the fnm zsh configuration patch (downloads zshrc/fnm.zsh to ~/.config/zshrc/fnm.zsh)
curl -fsSL https://git.miomio.moe/mio/easyzsh/raw/branch/master/patch.sh | bash -s fnm

echo -e "\nfnm installation completed!"
echo -e "To start using fnm, restart your terminal or run: source ~/.zshrc"
echo -e "\nUseful fnm commands:"
echo -e "  fnm install --lts          # Install latest LTS Node.js"
echo -e "  fnm install 18              # Install Node.js v18"
echo -e "  fnm use 18                  # Use Node.js v18"
echo -e "  fnm default 18              # Set Node.js v18 as default"
echo -e "  fnm list                    # List installed versions"
echo -e "  fnm list-remote             # List available versions"

# Restore original working directory
cd "$ORIGINAL_DIR"