#[cfg(feature = "compare")]
use std::env;
#[cfg(feature = "compare")]
use std::fs::File;
#[cfg(feature = "compare")]
use std::io::Write;
#[cfg(feature = "compare")]
use std::path::Path;

#[cfg(feature = "compare")]
use walkdir::WalkDir;

#[cfg(feature = "compare")]
fn main() {
    let out_dir = env::var("OUT_DIR").unwrap();
    let destination = Path::new(&out_dir).join("tests.rs");
    let mut test_file = File::create(destination).unwrap();

    // Re-generate the tests if any org-mode files change
    println!("cargo:rerun-if-changed=org_mode_samples");

    let test_files = WalkDir::new("org_mode_samples")
        .into_iter()
        .filter(|e| match e {
            Ok(dir_entry) => {
                dir_entry.file_type().is_file()
                    && Path::new(dir_entry.file_name())
                        .extension()
                        .map(|ext| ext.to_ascii_lowercase() == "org")
                        .unwrap_or(false)
            }
            Err(_) => true,
        })
        .collect::<Result<Vec<_>, _>>()
        .unwrap();
    for test in test_files {
        write_test(&mut test_file, &test);
    }
}

#[cfg(not(feature = "compare"))]
fn main() {}

#[cfg(feature = "compare")]
fn write_test(test_file: &mut File, test: &walkdir::DirEntry) {
    let test_name = test
        .path()
        .strip_prefix("org_mode_samples/")
        .expect("Paths should be under org_mode_samples/")
        .to_string_lossy()
        .to_lowercase()
        .strip_suffix(".org")
        .expect("Should have .org extension")
        .replace('/', "_");

    write!(
        test_file,
        include_str!("./tests/test_template"),
        name = test_name,
        path = test.path().display(),
        expect_fail = is_expect_fail(test_name.as_str())
            .map(|_| "#[ignore]\n")
            .unwrap_or("")
    )
    .unwrap();
}

#[cfg(feature = "compare")]
fn is_expect_fail(_name: &str) -> Option<&str> {
    None
}