use std::fs;
use std::path::PathBuf;

use clap::Parser;
use directories::ProjectDirs;
use itertools::Itertools;

use pep508_rs::Requirement;
use platform_host::Platform;
use puffin_client::RegistryClientBuilder;
use puffin_dispatch::BuildDispatch;
use puffin_interpreter::Virtualenv;
use puffin_traits::BuildContext;

#[derive(Parser)]
pub(crate) struct ResolveCliArgs {
    requirements: Vec<Requirement>,
    #[clap(long)]
    limit: Option<usize>,
    /// Path to the cache directory.
    #[arg(global = true, long, env = "PUFFIN_CACHE_DIR")]
    cache_dir: Option<PathBuf>,
    /// Don't build source distributions. This means resolving will not run arbitrary code. The
    /// cached wheels of already built source distributions will be reused.
    #[clap(long)]
    no_build: bool,
}

pub(crate) async fn resolve_cli(args: ResolveCliArgs) -> anyhow::Result<()> {
    let project_dirs = ProjectDirs::from("", "", "puffin");
    let cache = project_dirs
        .as_ref()
        .map(|project_dirs| project_dirs.cache_dir().to_path_buf())
        .or_else(|| Some(tempfile::tempdir().ok()?.into_path()))
        .unwrap_or_else(|| PathBuf::from(".puffin_cache"));

    let platform = Platform::current()?;
    let venv = Virtualenv::from_env(platform, Some(&cache))?;
    let build_dispatch = BuildDispatch::new(
        RegistryClientBuilder::default().cache(Some(&cache)).build(),
        cache.clone(),
        venv.interpreter_info().clone(),
        fs::canonicalize(venv.python_executable())?,
        args.no_build,
    );

    let mut resolution = build_dispatch.resolve(&args.requirements).await?;
    resolution.sort_unstable_by(|a, b| a.name.cmp(&b.name));
    // Concise format for dev
    println!("{}", resolution.iter().map(ToString::to_string).join(" "));

    Ok(())
}