/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

use dom::bindings::codegen::WindowBinding;
use dom::bindings::utils::{Reflectable, Reflector, Traceable};
use dom::bindings::utils::{trace_option, trace_reflector};
use dom::bindings::utils::DOMString;
use dom::document::AbstractDocument;
use dom::eventtarget::{EventTarget, WindowTypeId};
use dom::node::AbstractNode;
use dom::location::Location;
use dom::navigator::Navigator;

use layout_interface::{ReflowForDisplay, DocumentDamageLevel};
use script_task::{ExitWindowMsg, FireTimerMsg, Page, ScriptChan};
use servo_msg::compositor_msg::ScriptListener;
use servo_net::image_cache_task::ImageCacheTask;

use js::glue::*;
use js::jsapi::{JSObject, JSContext, JS_DefineProperty};
use js::jsapi::{JSPropertyOp, JSStrictPropertyOp, JSTracer};
use js::{JSVAL_NULL, JSPROP_ENUMERATE};

use std::cell::Cell;
use std::comm;
use std::comm::SharedChan;
use std::hashmap::HashSet;
use std::ptr;
use std::int;
use std::rt::io::timer::Timer;
use std::task::spawn_with;
use js::jsapi::JSVal;

pub enum TimerControlMsg {
    TimerMessage_Fire(~TimerData),
    TimerMessage_Close,
    TimerMessage_TriggerExit //XXXjdm this is just a quick hack to talk to the script task
}

pub struct Window {
    eventtarget: EventTarget,
    page: @mut Page,
    script_chan: ScriptChan,
    compositor: @ScriptListener,
    timer_chan: SharedChan<TimerControlMsg>,
    location: Option<@mut Location>,
    navigator: Option<@mut Navigator>,
    image_cache_task: ImageCacheTask,
    active_timers: ~HashSet<i32>,
    next_timer_handle: i32,
}

impl Window {
    pub fn get_cx(&self) -> *JSObject {
        self.page.js_info.get_ref().js_compartment.cx.ptr
    }
}

#[unsafe_destructor]
impl Drop for Window {
    fn drop(&mut self) {
        self.timer_chan.send(TimerMessage_Close);
    }
}

// Holder for the various JS values associated with setTimeout
// (ie. function value to invoke and all arguments to pass
//      to the function when calling it)
pub struct TimerData {
    handle: i32,
    funval: JSVal,
    args: ~[JSVal],
}

impl Window {
    pub fn Alert(&self, s: DOMString) {
        // Right now, just print to the console
        println(format!("ALERT: {:s}", s));
    }

    pub fn Close(&self) {
        self.timer_chan.send(TimerMessage_TriggerExit);
    }

    pub fn Document(&self) -> AbstractDocument {
        self.page.frame.unwrap().document
    }

    pub fn Name(&self) -> DOMString {
        ~""
    }

    pub fn SetName(&self, _name: DOMString) {
    }

    pub fn Status(&self) -> DOMString {
        ~""
    }

    pub fn SetStatus(&self, _status: DOMString) {
    }

    pub fn Closed(&self) -> bool {
        false
    }

    pub fn Stop(&self) {
    }

    pub fn Focus(&self) {
    }

    pub fn Blur(&self) {
    }

    pub fn GetFrameElement(&self) -> Option<AbstractNode> {
        None
    }

    pub fn Location(&mut self) -> @mut Location {
        if self.location.is_none() {
            self.location = Some(Location::new(self, self.page));
        }
        self.location.unwrap()
    }

    pub fn Navigator(&mut self) -> @mut Navigator {
        if self.navigator.is_none() {
            self.navigator = Some(Navigator::new(self));
        }
        self.navigator.unwrap()
    }

    pub fn Confirm(&self, _message: DOMString) -> bool {
        false
    }

    pub fn Prompt(&self, _message: DOMString, _default: DOMString) -> Option<DOMString> {
        None
    }

    pub fn Print(&self) {
    }

    pub fn ShowModalDialog(&self, _cx: *JSContext, _url: DOMString, _argument: JSVal) -> JSVal {
        JSVAL_NULL
    }
}

impl Reflectable for Window {
    fn reflector<'a>(&'a self) -> &'a Reflector {
        self.eventtarget.reflector()
    }

    fn mut_reflector<'a>(&'a mut self) -> &'a mut Reflector {
        self.eventtarget.mut_reflector()
    }
}

impl Window {
    pub fn SetTimeout(&mut self, _cx: *JSContext, callback: JSVal, timeout: i32) -> i32 {
        let timeout = int::max(0, timeout) as u64;
        let handle = self.next_timer_handle;
        self.next_timer_handle += 1;

        // Post a delayed message to the per-window timer task; it will dispatch it
        // to the relevant script handler that will deal with it.
        let tm = Cell::new(Timer::new().unwrap());
        let chan = self.timer_chan.clone();
        do spawn {
            let mut tm = tm.take();
            tm.sleep(timeout);
            chan.send(TimerMessage_Fire(~TimerData {
                handle: handle,
                funval: callback,
                args: ~[]
            }));
        }
        self.active_timers.insert(handle);
        handle
    }

    pub fn ClearTimeout(&mut self, handle: i32) {
        self.active_timers.remove(&handle);
    }

    pub fn damage_and_reflow(&self, damage: DocumentDamageLevel) {
        // FIXME This should probably be ReflowForQuery, not Display. All queries currently
        // currently rely on the display list, which means we can't destroy it by
        // doing a query reflow.
        self.page.damage(damage);
        self.page.reflow(ReflowForDisplay, self.script_chan.clone(), self.compositor);
    }

    pub fn wait_until_safe_to_modify_dom(&self) {
        // FIXME: This disables concurrent layout while we are modifying the DOM, since
        //        our current architecture is entirely unsafe in the presence of races.
        self.page.join_layout();
    }

    #[fixed_stack_segment]
    pub fn new(cx: *JSContext,
               page: @mut Page,
               script_chan: ScriptChan,
               compositor: @ScriptListener,
               image_cache_task: ImageCacheTask)
               -> @mut Window {
        let win = @mut Window {
            eventtarget: EventTarget::new_inherited(WindowTypeId),
            page: page,
            script_chan: script_chan.clone(),
            compositor: compositor,
            timer_chan: {
                let (timer_port, timer_chan) = comm::stream::<TimerControlMsg>();
                let id = page.id.clone();
                do spawn_with(script_chan) |script_chan| {
                    loop {
                        match timer_port.recv() {
                            TimerMessage_Close => break,
                            TimerMessage_Fire(td) => script_chan.send(FireTimerMsg(id, td)),
                            TimerMessage_TriggerExit => script_chan.send(ExitWindowMsg(id)),
                        }
                    }
                }
                SharedChan::new(timer_chan)
            },
            location: None,
            navigator: None,
            image_cache_task: image_cache_task,
            active_timers: ~HashSet::new(),
            next_timer_handle: 0
        };

        let global = WindowBinding::Wrap(cx, ptr::null(), win);
        unsafe {
            let fn_names = ["window","self"];
            for str in fn_names.iter() {
                do (*str).to_c_str().with_ref |name| {
                    JS_DefineProperty(cx, global,  name,
                                      RUST_OBJECT_TO_JSVAL(global),
                                      Some(GetJSClassHookStubPointer(PROPERTY_STUB) as JSPropertyOp),
                                      Some(GetJSClassHookStubPointer(STRICT_PROPERTY_STUB) as JSStrictPropertyOp),
                                      JSPROP_ENUMERATE);
                }

            }

        }
        win
    }
}

impl Traceable for Window {
    fn trace(&self, tracer: *mut JSTracer) {
        debug!("tracing window");

        self.page.frame.map(|frame| trace_reflector(tracer, "document", frame.document.reflector()));
        trace_option(tracer, "location", self.location);
        trace_option(tracer, "navigator", self.navigator);
    }
}