#![allow(non_snake_case)]
use crate::errors::{ERR_getErrorCode, ERR_getErrorName, ERR_isError, ZstdErrorCode};
use std::os::raw::{c_char, c_uint};

pub const ZSTD_VERSION_MAJOR: u32 = 1;
pub const ZSTD_VERSION_MINOR: u32 = 5;
pub const ZSTD_VERSION_RELEASE: u32 = 7;
pub const ZSTD_VERSION_NUMBER: u32 =
    ZSTD_VERSION_MAJOR * 100 * 100 + ZSTD_VERSION_MINOR * 100 + ZSTD_VERSION_RELEASE;

#[no_mangle]
pub extern "C" fn ZSTD_versionNumber() -> c_uint {
    ZSTD_VERSION_NUMBER
}

#[no_mangle]
pub extern "C" fn ZSTD_versionString() -> *const c_char {
    c"1.5.7".as_ptr()
}

#[no_mangle]
pub extern "C" fn ZSTD_isError(code: usize) -> c_uint {
    ERR_isError(code) as c_uint
}

#[no_mangle]
pub extern "C" fn ZSTD_getErrorName(code: usize) -> *const c_char {
    ERR_getErrorName(code)
}

#[no_mangle]
pub extern "C" fn ZSTD_getErrorCode(code: usize) -> i32 {
    ERR_getErrorCode(code)
}

// ZSTD_getErrorString lives in errors.rs (also used as ERR_getErrorString).

/// Convenience re-export of the error enum for callers of the common module.
pub type ErrorCode = ZstdErrorCode;

#[cfg(test)]
mod tests {
    use super::*;
    use crate::errors::{ZstdErrorCode, ERROR};
    use std::ffi::CStr;

    #[test]
    fn version_exports_match_zstd_h() {
        assert_eq!(ZSTD_versionNumber(), 10_507);
        let version = unsafe { CStr::from_ptr(ZSTD_versionString()) };
        assert_eq!(version.to_bytes(), b"1.5.7");
    }

    #[test]
    fn public_error_exports_preserve_numeric_codes() {
        let error = ERROR(ZstdErrorCode::CorruptionDetected);
        assert_eq!(ZSTD_isError(error), 1);
        assert_eq!(ZSTD_getErrorCode(error), 20);
        assert_eq!(ZSTD_getErrorCode(usize::MAX - 1), 2);
        let name = unsafe { CStr::from_ptr(ZSTD_getErrorName(error)) };
        assert_eq!(name.to_bytes(), b"Data corruption detected");
    }
}