//! One-file command-line harness for inspecting the actual lowering result.
use oa_core::{language, source_project::SourceBundle};
use std::{collections::BTreeMap, env, fs, process::ExitCode};

fn main() -> ExitCode {
    let args: Vec<_> = env::args().skip(1).collect();
    let rename = args.len() == 4 && args[0] == "--rename";
    if args.len() != 1 && !rename {
        eprintln!(
            "Usage: source-authoring-experiment B_SOURCE_FILE\n       source-authoring-experiment --rename B_SOURCE_FILE ALIAS NAME\nIncludes require the library's explicit SourceBundle API."
        );
        return ExitCode::FAILURE;
    }
    let result = fs::read_to_string(&args[usize::from(rename)])
        .map_err(|error| error.to_string())
        .and_then(|text| {
            let bundle = SourceBundle {
                entry: "project.arcadia".into(),
                files: BTreeMap::from([("project.arcadia".into(), text)]),
            };
            let project = source_authoring_experiment::compile(&bundle)?;
            if rename {
                let id = project
                    .identities()
                    .into_iter()
                    .find(|(_, alias)| *alias == args[2])
                    .map(|(id, _)| id)
                    .ok_or("Unknown declaration alias")?;
                let candidate = oa_core::execute_batch(
                    &project,
                    &[oa_core::Command::Rename(id, args[3].clone())],
                )
                .map_err(|error| error.to_string())?;
                let result =
                    source_authoring_experiment::writeback::writeback(&bundle, &candidate)?;
                Ok(result.files[&result.entry].clone())
            } else {
                Ok(language::format(&project))
            }
        });
    match result {
        Ok(text) => {
            print!("{text}");
            ExitCode::SUCCESS
        }
        Err(error) => {
            eprintln!("{error}");
            ExitCode::FAILURE
        }
    }
}