use myc::ast::compiler::CompilationResult;
use myc::ast::diagnostics::Diagnostics;
use myc::ast::environment::Environment;

// --- Diagnostics::format_errors() ---

#[test]
fn format_errors_empty() {
    let diag = Diagnostics::new();
    assert_eq!(diag.format_errors(), "");
}

#[test]
fn format_errors_single() {
    let mut diag = Diagnostics::new();
    diag.push_error("type mismatch", None);
    assert_eq!(diag.format_errors(), "type mismatch");
}

#[test]
fn format_errors_multiple_joined_with_newline() {
    let mut diag = Diagnostics::new();
    diag.push_error("first error", None);
    diag.push_error("second error", None);
    assert_eq!(diag.format_errors(), "first error\nsecond error");
}

#[test]
fn format_errors_ignores_warnings_and_hints() {
    let mut diag = Diagnostics::new();
    diag.push_warning("just a warning", None);
    diag.push_hint("a hint", None);
    diag.push_error("the real error", None);
    // Only the error should appear
    assert_eq!(diag.format_errors(), "the real error");
}

// --- CompilationResult ---

#[test]
fn compilation_result_error_into_err() {
    let result = CompilationResult::error("something went wrong");
    let err = result.into_result();
    assert!(err.is_err());
    assert_eq!(err.unwrap_err(), "something went wrong");
}

#[test]
fn compilation_result_success_into_ok() {
    // The success() constructor requires a TypedNode, which is produced by
    // the compiler. We verify the happy path via a minimal compile round-trip.
    let env = Environment::new();
    let result = env.compile("(+ 1 2)");
    assert!(!result.diagnostics.has_errors(), "unexpected errors: {}", result.diagnostics.format_errors());
    assert!(result.into_result().is_ok());
}