more refactoring

1 files changed, 351 insertions, 0 deletions

diff --git a/components/script/dom/htmlcanvaselement.rs.LOCAL.20237.rs b/components/script/dom/htmlcanvaselement.rs.LOCAL.20237.rs
new file mode 100644
index 00000000000..47126ed3dd0
--- /dev/null
+++ b/components/script/dom/htmlcanvaselement.rs.LOCAL.20237.rs
@@ -0,0 +1,351 @@
+/* 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 canvas_traits::{CanvasMsg, FromLayoutMsg};
+use dom::attr::Attr;
+use dom::bindings::cell::DOMRefCell;
+use dom::bindings::codegen::Bindings::CanvasRenderingContext2DBinding::CanvasRenderingContext2DMethods;
+use dom::bindings::codegen::Bindings::HTMLCanvasElementBinding;
+use dom::bindings::codegen::Bindings::HTMLCanvasElementBinding::HTMLCanvasElementMethods;
+use dom::bindings::codegen::Bindings::WebGLRenderingContextBinding::WebGLContextAttributes;
+use dom::bindings::codegen::UnionTypes::CanvasRenderingContext2DOrWebGLRenderingContext;
+use dom::bindings::conversions::Castable;
+use dom::bindings::error::{Error, Fallible};
+use dom::bindings::global::GlobalRef;
+use dom::bindings::js::{HeapGCValue, JS, LayoutJS, Root};
+use dom::bindings::num::Finite;
+use dom::bindings::utils::{Reflectable};
+use dom::canvasrenderingcontext2d::{CanvasRenderingContext2D, LayoutCanvasRenderingContext2DHelpers};
+use dom::document::Document;
+use dom::element::{AttributeMutation, Element};
+use dom::htmlelement::HTMLElement;
+use dom::node::{Node, window_from_node};
+use dom::virtualmethods::VirtualMethods;
+use dom::webglrenderingcontext::{LayoutCanvasWebGLRenderingContextHelpers, WebGLRenderingContext};
+use euclid::size::Size2D;
+use image::ColorType;
+use image::png::PNGEncoder;
+use ipc_channel::ipc::{self, IpcSender};
+use js::jsapi::{HandleValue, JSContext};
+use offscreen_gl_context::GLContextAttributes;
+use rustc_serialize::base64::{STANDARD, ToBase64};
+use std::cell::Cell;
+use std::iter::repeat;
+use util::str::{DOMString, parse_unsigned_integer};
+
+const DEFAULT_WIDTH: u32 = 300;
+const DEFAULT_HEIGHT: u32 = 150;
+
+#[must_root]
+#[derive(JSTraceable, Clone, HeapSizeOf)]
+pub enum CanvasContext {
+    Context2d(JS<CanvasRenderingContext2D>),
+    WebGL(JS<WebGLRenderingContext>),
+}
+
+impl HeapGCValue for CanvasContext {}
+
+#[dom_struct]
+pub struct HTMLCanvasElement {
+    htmlelement: HTMLElement,
+    context: DOMRefCell<Option<CanvasContext>>,
+    width: Cell<u32>,
+    height: Cell<u32>,
+}
+
+impl PartialEq for HTMLCanvasElement {
+    fn eq(&self, other: &HTMLCanvasElement) -> bool {
+        self as *const HTMLCanvasElement == &*other
+    }
+}
+
+impl HTMLCanvasElement {
+    fn new_inherited(localName: DOMString,
+                     prefix: Option<DOMString>,
+                     document: &Document) -> HTMLCanvasElement {
+        HTMLCanvasElement {
+            htmlelement: HTMLElement::new_inherited(localName, prefix, document),
+            context: DOMRefCell::new(None),
+            width: Cell::new(DEFAULT_WIDTH),
+            height: Cell::new(DEFAULT_HEIGHT),
+        }
+    }
+
+    #[allow(unrooted_must_root)]
+    pub fn new(localName: DOMString,
+               prefix: Option<DOMString>,
+               document: &Document) -> Root<HTMLCanvasElement> {
+        let element = HTMLCanvasElement::new_inherited(localName, prefix, document);
+        Node::reflect_node(box element, document, HTMLCanvasElementBinding::Wrap)
+    }
+
+    fn recreate_contexts(&self) {
+        let size = self.get_size();
+        if let Some(ref context) = *self.context.borrow() {
+            match *context {
+                CanvasContext::Context2d(ref context) => context.recreate(size),
+                CanvasContext::WebGL(ref context) => context.recreate(size),
+            }
+        }
+    }
+
+    pub fn get_size(&self) -> Size2D<i32> {
+        Size2D::new(self.width.get() as i32, self.height.get() as i32)
+    }
+}
+
+pub struct HTMLCanvasData {
+    pub renderer_id: Option<usize>,
+    pub ipc_renderer: Option<IpcSender<CanvasMsg>>,
+    pub width: u32,
+    pub height: u32,
+}
+
+pub trait LayoutHTMLCanvasElementHelpers {
+    fn data(&self) -> HTMLCanvasData;
+}
+
+impl LayoutHTMLCanvasElementHelpers for LayoutJS<HTMLCanvasElement> {
+    #[allow(unsafe_code)]
+    fn data(&self) -> HTMLCanvasData {
+        unsafe {
+            let canvas = &*self.unsafe_get();
+            let (renderer_id, ipc_renderer) = match canvas.context.borrow_for_layout().as_ref() {
+                Some(&CanvasContext::Context2d(ref context)) => {
+                    let context = context.to_layout();
+                    (Some(context.get_renderer_id()), Some(context.get_ipc_renderer()))
+                },
+                Some(&CanvasContext::WebGL(ref context)) => {
+                    let context = context.to_layout();
+                    (Some(context.get_renderer_id()), Some(context.get_ipc_renderer()))
+                },
+                None => (None, None),
+            };
+
+            HTMLCanvasData {
+                renderer_id: renderer_id,
+                ipc_renderer: ipc_renderer,
+                width: canvas.width.get(),
+                height: canvas.height.get(),
+            }
+        }
+    }
+}
+
+
+impl HTMLCanvasElement {
+    pub fn ipc_renderer(&self) -> Option<IpcSender<CanvasMsg>> {
+        self.context.borrow().as_ref().map(|context| {
+            match *context {
+                CanvasContext::Context2d(ref context) => context.ipc_renderer(),
+                CanvasContext::WebGL(ref context) => context.ipc_renderer(),
+            }
+        })
+    }
+
+    pub fn get_or_init_2d_context(&self) -> Option<Root<CanvasRenderingContext2D>> {
+        if self.context.borrow().is_none() {
+            let window = window_from_node(self);
+            let size = self.get_size();
+            let context = CanvasRenderingContext2D::new(GlobalRef::Window(window.r()), self, size);
+            *self.context.borrow_mut() = Some(CanvasContext::Context2d(JS::from_rooted(&context)));
+        }
+
+        match *self.context.borrow().as_ref().unwrap() {
+            CanvasContext::Context2d(ref context) => Some(context.root()),
+            _   => None,
+        }
+    }
+
+    pub fn get_or_init_webgl_context(&self,
+                                 cx: *mut JSContext,
+                                 attrs: Option<HandleValue>) -> Option<Root<WebGLRenderingContext>> {
+        if self.context.borrow().is_none() {
+            let window = window_from_node(self);
+            let size = self.get_size();
+
+            let attrs = if let Some(webgl_attributes) = attrs {
+                if let Ok(ref attrs) = WebGLContextAttributes::new(cx, webgl_attributes) {
+                    From::from(attrs)
+                } else {
+                    debug!("Unexpected error on conversion of WebGLContextAttributes");
+                    return None;
+                }
+            } else {
+                GLContextAttributes::default()
+            };
+
+            let maybe_ctx = WebGLRenderingContext::new(GlobalRef::Window(window.r()), self, size, attrs);
+
+            *self.context.borrow_mut() = maybe_ctx.map( |ctx| CanvasContext::WebGL(JS::from_rooted(&ctx)));
+        }
+
+        if let Some(CanvasContext::WebGL(ref context)) = *self.context.borrow() {
+            Some(context.root())
+        } else {
+            None
+        }
+    }
+
+    pub fn is_valid(&self) -> bool {
+        self.height.get() != 0 && self.width.get() != 0
+    }
+
+    pub fn fetch_all_data(&self) -> Option<(Vec<u8>, Size2D<i32>)> {
+        let size = self.get_size();
+
+        if size.width == 0 || size.height == 0 {
+            return None
+        }
+
+        let data = if let Some(renderer) = self.ipc_renderer() {
+            let (sender, receiver) = ipc::channel().unwrap();
+            let msg = CanvasMsg::FromLayout(FromLayoutMsg::SendPixelContents(sender));
+            renderer.send(msg).unwrap();
+
+            receiver.recv().unwrap().to_vec()
+        } else {
+            repeat(0xffu8).take((size.height as usize) * (size.width as usize) * 4).collect()
+        };
+
+        Some((data, size))
+    }
+}
+
+impl HTMLCanvasElementMethods for HTMLCanvasElement {
+    // https://html.spec.whatwg.org/multipage/#dom-canvas-width
+    fn Width(&self) -> u32 {
+        self.width.get()
+    }
+
+    // https://html.spec.whatwg.org/multipage/#dom-canvas-width
+    fn SetWidth(&self, width: u32) {
+        self.upcast::<Element>().set_uint_attribute(&atom!("width"), width)
+    }
+
+    // https://html.spec.whatwg.org/multipage/#dom-canvas-height
+    fn Height(&self) -> u32 {
+        self.height.get()
+    }
+
+    // https://html.spec.whatwg.org/multipage/#dom-canvas-height
+    fn SetHeight(&self, height: u32) {
+        self.upcast::<Element>().set_uint_attribute(&atom!("height"), height)
+    }
+
+    // https://html.spec.whatwg.org/multipage/#dom-canvas-getcontext
+    fn GetContext(&self,
+                  cx: *mut JSContext,
+                  id: DOMString,
+                  attributes: Vec<HandleValue>)
+        -> Option<CanvasRenderingContext2DOrWebGLRenderingContext> {
+        match &*id {
+            "2d" => {
+                self.get_or_init_2d_context()
+                    .map(CanvasRenderingContext2DOrWebGLRenderingContext::eCanvasRenderingContext2D)
+            }
+            "webgl" | "experimental-webgl" => {
+                self.get_or_init_webgl_context(cx, attributes.get(0).map(|p| *p))
+                    .map(CanvasRenderingContext2DOrWebGLRenderingContext::eWebGLRenderingContext)
+            }
+            _ => None
+        }
+    }
+
+    // https://html.spec.whatwg.org/multipage/#dom-canvas-todataurl
+    fn ToDataURL(&self,
+                 _context: *mut JSContext,
+                 _mime_type: Option<DOMString>,
+                 _arguments: Vec<HandleValue>) -> Fallible<DOMString> {
+
+        // Step 1: Check the origin-clean flag (should be set in fillText/strokeText
+        // and currently unimplemented)
+
+        // Step 2.
+        if self.Width() == 0 || self.Height() == 0 {
+            return Ok("data:,".to_owned());
+        }
+
+        // Step 3.
+        if let Some(CanvasContext::Context2d(ref context)) = *self.context.borrow() {
+            let window = window_from_node(self);
+            let image_data = try!(context.GetImageData(Finite::wrap(0f64), Finite::wrap(0f64),
+                                                       Finite::wrap(self.Width() as f64),
+                                                       Finite::wrap(self.Height() as f64)));
+            let raw_data = image_data.get_data_array(&GlobalRef::Window(window.r()));
+
+            // Only handle image/png for now.
+            let mime_type = "image/png";
+
+            let mut encoded = Vec::new();
+            {
+                let encoder: PNGEncoder<&mut Vec<u8>> = PNGEncoder::new(&mut encoded);
+                encoder.encode(&raw_data, self.Width(), self.Height(), ColorType::RGBA(8)).unwrap();
+            }
+
+            let encoded = encoded.to_base64(STANDARD);
+            Ok(format!("data:{};base64,{}", mime_type, encoded))
+        } else {
+            Err(Error::NotSupported)
+        }
+    }
+}
+
+impl VirtualMethods for HTMLCanvasElement {
+    fn super_type(&self) -> Option<&VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    }
+
+    fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
+        self.super_type().unwrap().attribute_mutated(attr, mutation);
+        let recreate = match attr.local_name() {
+            &atom!(width) => {
+                let width = mutation.new_value(attr).and_then(|value| {
+                    parse_unsigned_integer(value.chars())
+                });
+                self.width.set(width.unwrap_or(DEFAULT_WIDTH));
+                true
+            },
+            &atom!(height) => {
+                let height = mutation.new_value(attr).and_then(|value| {
+                    parse_unsigned_integer(value.chars())
+                });
+                self.height.set(height.unwrap_or(DEFAULT_HEIGHT));
+                true
+            },
+            _ => false,
+        };
+        if recreate {
+            self.recreate_contexts();
+        }
+    }
+}
+
+impl<'a> From<&'a WebGLContextAttributes> for GLContextAttributes {
+    fn from(attrs: &'a WebGLContextAttributes) -> GLContextAttributes {
+        GLContextAttributes {
+            alpha: attrs.alpha,
+            depth: attrs.depth,
+            stencil: attrs.stencil,
+            antialias: attrs.antialias,
+            premultiplied_alpha: attrs.premultipliedAlpha,
+            preserve_drawing_buffer: attrs.preserveDrawingBuffer,
+        }
+    }
+}
+
+pub mod utils {
+    use dom::window::Window;
+    use ipc_channel::ipc;
+    use net_traits::image_cache_task::{ImageCacheChan, ImageResponse};
+    use url::Url;
+
+    pub fn request_image_from_cache(window: &Window, url: Url) -> ImageResponse {
+        let image_cache = window.image_cache_task();
+        let (response_chan, response_port) = ipc::channel().unwrap();
+        image_cache.request_image(url, ImageCacheChan(response_chan), None);
+        let result = response_port.recv().unwrap();
+        result.image_response
+    }
+}