//! Platform-specific helpers for BELT.
//!
//! Provides OS detection and default Factorio installation path discovery.

use std::path::PathBuf;

/// Get all reasonable Factorio paths based on the user's operating system
pub fn get_default_factorio_paths() -> Vec<PathBuf> {
    let mut paths = Vec::new();

    if cfg!(target_os = "windows") {
        // Check all drives A: through Z: for Steam installation
        for drive_letter in b'A'..=b'Z' {
            let drive = char::from(drive_letter);

            // Steam
            paths.push(PathBuf::from(format!(
                r"{drive}:\Program Files (x86)\Steam\steamapps\common\Factorio\bin\x64\factorio.exe",
            )));

            // Standalone
            paths.push(PathBuf::from(format!(
                r"{drive}:\Program Files\Factorio\bin\x64\factorio.exe",
            )));
        }

        // User steam library (uncommon)
        if let Some(home) = dirs::home_dir() {
            paths.push(
                home.join(r"AppData\Local\Steam\steamapps\common\Factorio\bin\x64\factorio.exe"),
            );
        }
    } else if cfg!(target_os = "linux") {
        // User bin (symlinked, personally have this)
        if let Some(home) = dirs::home_dir() {
            paths.push(home.join(".local/bin/factorio"));
        }
        // System wide
        paths.push(PathBuf::from("/usr/local/bin/factorio"));
        paths.push(PathBuf::from("/usr/bin/factorio"));
        paths.push(PathBuf::from("/opt/factorio/bin/x64/factorio"));
        // Steam on Linux
        if let Some(home) = dirs::home_dir() {
            paths.push(home.join(".steam/steam/steamapps/common/Factorio/bin/x64/factorio"));
            paths.push(home.join(".local/share/Steam/steamapps/common/Factorio/bin/x64/factorio"));
        }
    } else if cfg!(target_os = "macos") {
        if let Some(home) = dirs::home_dir() {
            paths.push(home.join(
                "Library/Application Support/Steam/steamapps/common/Factorio/factorio.app/Contents/MacOS/factorio",
            ));
        }
        paths.push(PathBuf::from(
            "/Applications/factorio.app/Contents/MacOS/factorio",
        ));
    }

    paths
}
