use std::{ffi::CString};
use libc::{c_void, c_int, c_char};


extern "C" {
    pub fn new_appender(name: *const c_char, attributes: *const c_char) -> c_int;
    pub fn delete_appender(app_id: c_int) -> c_void;
    pub fn write(app_id: c_int, level: c_int, log: *const c_char) -> c_void;
 }

/// 日志添加器
/// #[derive(Debug)]
pub struct Appender {
    app_id: c_int, // 日志添加器ID
}

impl Appender {
    pub fn new(name : &str, attributes : &str) -> Option<Appender> {
        unsafe {
            let name_ptr = CString::new(name).unwrap();
            let attributes_ptr = CString::new(attributes).unwrap();
            let appender = Appender {
                app_id:  new_appender(name_ptr.as_ptr(), attributes_ptr.as_ptr()),
            };
            return Some(appender);
        };        
    }

    pub fn verb(&mut self, log: &str) {
        self.write(1, log);
    }

    pub fn info(&mut self, log: &str) {
        self.write(2, log);
    }

    pub fn debug(&mut self, log: &str) {
        self.write(3, log);
    }

    pub fn warn(&mut self, log: &str) {
        self.write(4, log);
    }

    pub fn except(&mut self, log: &str) {
        self.write(5, log);
    }

    pub fn fail(&mut self, log: &str) {
        self.write(6, log);
    }

    pub fn fatal(&mut self, log: &str) {
        self.write(7, log);
    }

    fn write(&mut self, level : i32, log : &str) {
        unsafe {
            let log_ptr = CString::new(log).unwrap();
            write(self.app_id, level, log_ptr.as_ptr());
        }
    }
}

impl Drop for Appender {
    fn drop(&mut self) {
        unsafe {
            delete_appender(self.app_id);
        }
    }
}

#[cfg(test)]
mod tests {
    use super::Appender;

    #[test]
    fn test_new_appender1() {
        let mut app  = Appender::new("test", "console://;line=[%y%m%d-%H:%M:%S.%U];flush=true").unwrap();
        app.verb("verb log");
        app.info("info log");
        app.debug("debug log");
        app.warn("warn log");
        app.except("except log");
        app.fail("fail log");
        app.fatal("fatal log");
    }
}