extern crate gtk;
extern crate gtk_sys;
extern crate gio;
extern crate gdk;
extern crate gdk_sys;
extern crate glib;
extern crate cairo;
extern crate pango;
extern crate pangocairo;
extern crate neovim_lib;
extern crate phf;

mod nvim;
mod ui_model;
mod ui;
mod input;
mod settings;

use std::thread;
use std::env;
use gio::ApplicationExt;

const BIN_PATH_ARG: &'static str = "--nvim-bin-path";

fn main() {
    let app = gtk::Application::new(Some("org.gtk.neovim-gtk"), gio::ApplicationFlags::empty()).expect("Failed to initialize GTK application");

    app.connect_activate(activate);

    let args: Vec<String> = env::args().collect();
    let mut argv: Vec<&str> = args.iter().filter(|a| !a.starts_with(BIN_PATH_ARG)).map(String::as_str).collect();
    if open_arg().is_some() {
        argv.pop();
    }
    app.run(argv.len() as i32, &argv);
}

fn activate(app: &gtk::Application) {
    ui::UI.with(|ui_cell| {
        let mut ui = ui_cell.borrow_mut();
        ui.init(app);

        let path = nvim_bin_path(std::env::args());
        let open_arg = open_arg();
        nvim::initialize(&mut *ui, path.as_ref(), open_arg.as_ref()).expect("Can't start nvim instance");

        guard_dispatch_thread(&mut *ui);
    });
}

fn nvim_bin_path<I>(args: I) -> Option<String> 
    where I: Iterator<Item=String>
{
    args.skip_while(|a| !a.starts_with(BIN_PATH_ARG))
        .map(|p| p.split('=').nth(1).map(str::to_owned))
        .nth(0)
        .unwrap_or(None)
}

fn open_arg() -> Option<String> {
   open_arg_impl(std::env::args())
}

fn open_arg_impl<I>(args: I) -> Option<String> 
    where I: Iterator<Item=String>
{
    args.last().map(|a| {
        if !a.starts_with("-") {
            Some(a.to_owned())
        } else {
            None
        }
    }).unwrap_or(None)
}

fn guard_dispatch_thread(ui: &mut ui::Ui) {
    let guard = ui.nvim().session.take_dispatch_guard();
    thread::spawn(move || {
        guard.join().expect("Can't join dispatch thread");
        glib::idle_add(move || {
            ui::UI.with(|ui_cell| {
                ui_cell.borrow().destroy();
            });
            glib::Continue(false)
        });
    });
}

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

    #[test]
    fn test_bin_path_arg() {
        assert_eq!(Some("/test_path".to_string()), 
                   nvim_bin_path(vec!["neovim-gtk", "--nvim-bin-path=/test_path"].iter().map(|s| s.to_string())));
    }

    #[test]
    fn test_open_arg() {
        assert_eq!(Some("some_file.txt".to_string()), 
                   open_arg_impl(vec!["neovim-gtk", "--nvim-bin-path=/test_path", "some_file.txt"].iter().map(|s| s.to_string())));
    }
}