use std::ffi::c_void;

use crate::bindings;
use crate::util;

pub struct Menu {
    ptr: *mut bindings::Menuwidget,
    data: *mut bindings::Menudata,
}

pub struct Data {
    items: Vec<Item>,
}

pub struct Item {
    text: String,
    hotkey: i32,
    func: Option<unsafe extern "C" fn(index: i32)>,
}

pub enum KeyResult {
    Handled, Ignored, Quit, Called,
}

impl Menu {
    pub fn new(lefttop: (u32, u32), data: Data) -> Menu {
        unsafe {
            let mdata = util::malloc::<bindings::Menudata>(1);
            let mitems = util::malloc::<bindings::Menuitem>(data.items.len());

            (*mdata).nitems = data.items.len() as i32;
            (*mdata).items = mitems;

            for i in 0..data.items.len() {
                (*mitems.add(i)).text = util::strdup(&data.items[i].text);
                (*mitems.add(i)).hotkey = data.items[i].hotkey;
                (*mitems.add(i)).func = data.items[i].func;
            }

            Menu {
                ptr: bindings::menu_make(
                         lefttop.0 as i32, lefttop.1 as i32,
                         mdata),
                data: mdata,
            }
        }
    }

    pub fn redraw(&self) {
        unsafe { bindings::menu_redraw(self.ptr); }
    }

    pub fn handle_key(&mut self, key: i32) -> KeyResult {
        match unsafe { bindings::menu_handlekey(self.ptr, key) } {
            bindings::Menukey_MENUKEY_HANDLED => KeyResult::Handled,
            bindings::Menukey_MENUKEY_IGNORED => KeyResult::Ignored,
            bindings::Menukey_MENUKEY_QUIT => KeyResult::Quit,
            bindings::Menukey_MENUKEY_CALLED => KeyResult::Called,
            _ => panic!("Invalid Menukey received from termio"),
        }
    }
}

impl Drop for Menu {
    fn drop(&mut self) {
        unsafe {
            bindings::menu_destroy(self.ptr);

            let nitems = (*self.data).nitems as usize;
            let mitems = (*self.data).items;

            for i in 0..nitems {
                libc::free((*mitems.add(i)).text as *mut c_void);
            }

            libc::free(mitems as *mut c_void);
            libc::free(self.data as *mut c_void);
        }
    }
}