#!/usr/bin/env nu
# OS detection utilities
# Detect running OS and return structured results

use std

# Detect current OS type
export def detect [] {
    let os_info = (^uname -s | str trim)

    if $os_info == "Linux" {
        # Check for NixOS (most distinctive)
        if ("/etc/os-release" | path exists) {
            let release_info = (open /etc/os-release)
            if ($release_info | str contains "nixos" or $release_info | str contains "NixOS") {
                "nixos"
            } else if ($release_info | str contains "Ubuntu") {
                "ubuntu"
            } else if ($release_info | str contains "Debian") {
                "debian"
            } else if ($release_info | str contains "Alpine") {
                "alpine"
            } else {
                "linux-generic"
            }
        } else {
            "linux-generic"
        }
    } else if $os_info == "Darwin" {
        "macos"
    } else if ($os_info | str starts-with "MINGW") {
        "windows"
    } else {
        $"unknown($os_info)"
    }
}

# Detect CPU architecture
export def detect-arch [] {
    let arch_raw = (^uname -m | str trim)

    match $arch_raw {
        "x86_64" => { "x86_64" }
        "aarch64" | "arm64" => { "aarch64" }
        "armv7l" | "armv7" => { "armv7" }
        "i386" | "i686" => { "i386" }
        _ => { $arch_raw }
    }
}

# Get system information as record
export def info [] {
    {
        os: (detect),
        arch: (detect-arch),
        kernel: (^uname -s | str trim),
        release: (^uname -r | str trim),
    }
}

# Validate OS type is supported
export def is-supported [os_type: string] {
    $os_type in ["debian" "ubuntu" "nixos" "alpine" "linux-generic" "macos"]
}

# Check if running on NixOS
export def is-nixos [] {
    (detect) == "nixos"
}

# Check if running on Debian-based
export def is-debian-based [] {
    let current = (detect)
    $current in ["debian" "ubuntu"]
}

# Main: Print OS info
export def main [] {
    let system_info = (info)

    print $"OS: ($system_info.os)"
    print $"Architecture: ($system_info.arch)"
    print $"Kernel: ($system_info.kernel)"
    print $"Release: ($system_info.release)"
}