zoi-core 1.25.4

use std::fs::{self, File};
use std::io::{self, Read, Write};
use std::path::PathBuf;

use serde::{Deserialize, Serialize};

/// Represents a package pinned to a specific version from a specific source.
#[derive(Serialize, Deserialize, Debug, Clone)]
pub struct PinnedPackage {
    /// The source of the package (e.g. its PURL or name).
    pub source: String,
    /// The specific version the package is pinned to.
    pub version: String
}

/// Returns the path to the `pinned.json` file in the user's Zoi directory.
fn get_pinned_json_path() -> Result<PathBuf, io::Error> {
    let home_dir = dirs::home_dir().ok_or_else(|| {
        io::Error::new(io::ErrorKind::NotFound, "Could not find home directory")
    })?;
    let zoi_dir = home_dir.join(".zoi");
    if !zoi_dir.exists() {
        fs::create_dir_all(&zoi_dir)?;
    }
    Ok(zoi_dir.join("pinned.json"))
}

/// Loads the list of pinned packages from `pinned.json`.
///
/// # Errors
///
/// Returns an `io::Error` if the home directory cannot be found, if creating
/// the `.zoi` directory fails, or if reading the `pinned.json` file fails.
pub fn get_pinned_packages() -> Result<Vec<PinnedPackage>, io::Error> {
    let path = get_pinned_json_path()?;
    if !path.exists() {
        return Ok(Vec::new());
    }

    let mut file = File::open(path)?;
    let mut contents = String::new();
    file.read_to_string(&mut contents)?;

    let packages: Vec<PinnedPackage> =
        serde_json::from_str(&contents).unwrap_or_else(|_| Vec::new());
    Ok(packages)
}

/// Saves the list of pinned packages to `pinned.json`.
///
/// # Errors
///
/// Returns an `io::Error` if the home directory cannot be found, if creating
/// the `.zoi` directory fails, or if writing to `pinned.json` fails.
pub fn write_pinned_packages(
    packages: &[PinnedPackage]
) -> Result<(), io::Error> {
    let path = get_pinned_json_path()?;
    let mut file = File::create(path)?;
    let contents = serde_json::to_string_pretty(packages)?;
    file.write_all(contents.as_bytes())?;
    Ok(())
}

/// Retrieves the pinned version for a given source, if it exists.
///
/// # Errors
///
/// Returns an `io::Error` if loading the pinned packages fails.
pub fn get_pinned_version(source: &str) -> Result<Option<String>, io::Error> {
    let pinned_packages = get_pinned_packages()?;
    Ok(pinned_packages
        .iter()
        .find(|p| p.source == source)
        .map(|p| p.version.clone()))
}

/// Checks if a source has a pinned version.
///
/// # Errors
///
/// Returns an `io::Error` if loading the pinned packages fails.
pub fn is_pinned(source: &str) -> Result<bool, io::Error> {
    let pinned_packages = get_pinned_packages()?;
    Ok(pinned_packages.iter().any(|p| p.source == source))
}