#![cfg(target_os = "linux")]

use Api;
use BuilderAttribs;
use ContextError;
use CreationError;
use GlContext;
use PixelFormat;
use libc;

use api::osmesa::{self, OsMesaContext};

#[cfg(feature = "window")]
pub use self::api_dispatch::{Window, WindowProxy, MonitorID, get_available_monitors, get_primary_monitor};
#[cfg(feature = "window")]
pub use self::api_dispatch::{WaitEventsIterator, PollEventsIterator};
#[cfg(feature = "window")]
mod api_dispatch;

#[cfg(not(feature = "window"))]
pub type Window = ();       // TODO: hack to make things work
#[cfg(not(feature = "window"))]
pub type MonitorID = ();       // TODO: hack to make things work

pub struct HeadlessContext(OsMesaContext);

impl HeadlessContext {
    pub fn new(builder: BuilderAttribs) -> Result<HeadlessContext, CreationError> {
        match OsMesaContext::new(builder) {
            Ok(c) => return Ok(HeadlessContext(c)),
            Err(osmesa::OsMesaCreationError::NotSupported) => (),
            Err(osmesa::OsMesaCreationError::CreationError(e)) => return Err(e),
        };

        Err(CreationError::NotSupported)
    }
}

impl GlContext for HeadlessContext {
    #[inline]
    unsafe fn make_current(&self) -> Result<(), ContextError> {
        self.0.make_current()
    }

    #[inline]
    fn is_current(&self) -> bool {
        self.0.is_current()
    }

    #[inline]
    fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
        self.0.get_proc_address(addr)
    }

    #[inline]
    fn swap_buffers(&self) -> Result<(), ContextError> {
        self.0.swap_buffers()
    }

    #[inline]
    fn get_api(&self) -> Api {
        self.0.get_api()
    }

    #[inline]
    fn get_pixel_format(&self) -> PixelFormat {
        self.0.get_pixel_format()
    }
}