Files
AstralRinth/theseus/src/modpack/mod.rs
2021-11-20 12:02:46 -08:00

69 lines
2.3 KiB
Rust

//! Provides utilties for downloading and parsing modpacks
use std::{convert::TryFrom, io, path::Path};
use fs_extra::dir::CopyOptions;
use tokio::fs;
use self::manifest::Manifest;
mod manifest;
pub const MANIFEST_PATH: &'static str = "index.json";
pub const OVERRIDES_PATH: &'static str = "overrides/";
#[derive(thiserror::Error, Debug)]
pub enum ModpackError {
#[error("I/O error while reading modpack: {0}")]
IOError(#[from] io::Error),
#[error("I/O error while reading modpack: {0}")]
FSExtraError(#[from] fs_extra::error::Error),
#[error("Invalid output directory: {0}")]
InvalidDirectory(String),
#[error("Error parsing manifest: {0}")]
ManifestError(String),
#[error("Daedalus error: {0}")]
DaedalusError(#[from] daedalus::Error),
#[error("Error parsing json: {0}")]
JsonError(#[from] serde_json::Error),
#[error("Error joining futures: {0}")]
JoinError(#[from] tokio::task::JoinError),
}
/// Realise a given modpack into an instance
pub async fn realise_modpack(dir: &Path, dest: &Path, side: &manifest::ModpackSide) -> Result<(), ModpackError> {
if dest.is_file() {
return Err(ModpackError::InvalidDirectory(String::from("Output is not a directory")));
}
if dest.exists() && std::fs::read_dir(dest).map_or(false, |it| it.count() != 0) {
return Err(ModpackError::InvalidDirectory(String::from("Output directory is non-empty")));
}
if !dest.exists() {
fs::create_dir_all(dest).await?;
}
// Copy overrides
let overrides = Some(dir.join(OVERRIDES_PATH)).filter(|it| it.exists() && it.is_dir());
if let Some(overrides) = overrides {
fs_extra::dir::copy(overrides, dest, &CopyOptions::new())?;
}
// Parse manifest
// NOTE: I'm using standard files here, since Serde does not support async readers
let manifest_path = Some(dir.join(MANIFEST_PATH))
.filter(|it| it.exists() && it.is_file())
.ok_or(ModpackError::ManifestError(String::from("Manifest missing or is not a file")))?;
let manifest_file = std::fs::File::open(manifest_path)?;
let manifest_json: serde_json::Value = serde_json::from_reader(io::BufReader::new(manifest_file))?;
let manifest = Manifest::try_from(manifest_json)?;
// Realise manifest
manifest.download_files(dest, side).await?;
Ok(())
}