use std::io::Write;
use std::path::Path;

use dever_backend_bridge::{Target, emit_object};
use dever_core::source::SourceMap;
use dever_runtime::config::Settings;

fn main() -> Result<(), String> {
    let arguments = std::env::args_os().skip(1).collect::<Vec<_>>();
    let (project, output, ir) = match arguments.as_slice() {
        [project, output] => (project, output, None),
        [project, output, ir] => (project, output, Some(ir)),
        _ => {
            return Err("usage: api-json-object <project> <new-object-file> [new-ir-file]".into());
        }
    };
    let project = Path::new(project);
    let sources =
        SourceMap::load(&project.join("module")).map_err(|errors| format!("{errors:?}"))?;
    let settings = Settings::load_project(project).map_err(|error| error.to_string())?;
    let program = dever_core::check_with_settings(&sources, &settings).map_err(|errors| {
        errors
            .iter()
            .map(|error| error.render(&sources))
            .collect::<String>()
    })?;
    let errors = program.application_errors()?;
    if !errors.is_empty() {
        return Err(errors
            .iter()
            .map(|error| error.render(&sources))
            .collect::<String>());
    }
    let module = dever_core::llvm::emit_executable(&program, &sources)?;
    if let Some(ir) = ir {
        let mut ir = std::fs::OpenOptions::new()
            .write(true)
            .create_new(true)
            .open(ir)
            .map_err(|error| error.to_string())?;
        ir.write_all(module.as_bytes())
            .map_err(|error| error.to_string())?;
    }
    let object = emit_object(&module, Target::LinuxX86_64)?;
    let mut output = std::fs::OpenOptions::new()
        .write(true)
        .create_new(true)
        .open(output)
        .map_err(|error| error.to_string())?;
    output.write_all(&object).map_err(|error| error.to_string())
}