auto merge of #1631 : recrack/servo/background-image, r=SimonSapin

for #777 #800

- support(http://www.w3.org/TR/CSS21/colors.html#background)
 - background: url(foo.png)
 - background: url(data:image/png;base64...)
 - background-image: url(foo.png)
 - background-image: url(data:image/png;base64...)

- not support(http://www.w3.org/TR/css3-background/)

11 files changed, 249 insertions, 28 deletions

diff --git a/src/components/main/layout/box_.rs b/src/components/main/layout/box_.rs
index bcbb0ccebd1..d50d76ccb0a 100644
--- a/src/components/main/layout/box_.rs
+++ b/src/components/main/layout/box_.rs
@@ -22,6 +22,7 @@ use servo_util::geometry::Au;
 use servo_util::geometry;
 use servo_util::range::*;
 use servo_util::namespace;
+
 use std::cast;
 use std::cell::RefCell;
 use std::cmp::ApproxEq;
@@ -937,6 +938,7 @@ impl Box {
     /// necessary.
     pub fn paint_background_if_applicable<E:ExtraDisplayListData>(
                                           &self,
+                                          builder: &DisplayListBuilder,
                                           index: uint,
                                           lists: &RefCell<DisplayListCollection<E>>,
                                           absolute_bounds: &Rect<Au>) {
@@ -959,6 +961,39 @@ impl Box {
                 lists.lists[index].append_item(SolidColorDisplayItemClass(solid_color_display_item))
             });
         }
+
+        // The background image is painted on top of the background color.
+        // Implements background image, per spec:
+        // http://www.w3.org/TR/CSS21/colors.html#background
+        match style.Background.get().background_image {
+            Some(ref image_url) => {
+                let mut holder = ImageHolder::new(image_url.clone(), builder.ctx.image_cache.clone());
+                match holder.get_image() {
+                    Some(image) => {
+                        debug!("(building display list) building background image");
+
+                        // Place the image into the display list.
+                        lists.with_mut(|lists| {
+                            let image_display_item = ~ImageDisplayItem {
+                                base: BaseDisplayItem {
+                                    bounds: *absolute_bounds,
+                                    extra: ExtraDisplayListData::new(self),
+                                },
+                                image: image.clone(),
+                            };
+                            lists.lists[index].append_item(ImageDisplayItemClass(image_display_item));
+                        });
+                    }
+                    None => {
+                        // No image data at all? Do nothing.
+                        //
+                        // TODO: Add some kind of placeholder background image.
+                        debug!("(building display list) no background image :(");
+                    }
+                }
+            }
+            None => {}
+        }
     }
 
     /// Adds the display items necessary to paint the borders of this box to a display list if
@@ -1052,7 +1087,7 @@ impl Box {
 
         self.paint_inline_background_border_if_applicable(index, lists, &absolute_box_bounds, &offset);
         // Add the background to the list, if applicable.
-        self.paint_background_if_applicable(index, lists, &absolute_box_bounds);
+        self.paint_background_if_applicable(builder, index, lists, &absolute_box_bounds);
 
         match self.specific {
             UnscannedTextBox(_) => fail!("Shouldn't see unscanned boxes here."),
@@ -1259,7 +1294,6 @@ impl Box {
         //
         // TODO: Outlines.
         self.paint_borders_if_applicable(index, lists, &absolute_box_bounds);
-
     }
 
     /// Returns the *minimum width* and *preferred width* of this box as defined by CSS 2.1.
diff --git a/src/components/script/dom/element.rs b/src/components/script/dom/element.rs
index 9ffb17c3254..2eb0553f2f6 100644
--- a/src/components/script/dom/element.rs
+++ b/src/components/script/dom/element.rs
@@ -221,7 +221,9 @@ impl Element {
 
         match local_name.as_slice() {
             "style" => {
-                self.style_attribute = Some(style::parse_style_attribute(value))
+                let doc = self.node.owner_doc();
+                let base_url = doc.document().url.clone();
+                self.style_attribute = Some(style::parse_style_attribute(value, &base_url))
             }
             "id" if abstract_self.is_in_doc() => {
                 // XXX: this dual declaration are workaround to avoid the compile error:
diff --git a/src/components/script/html/hubbub_html_parser.rs b/src/components/script/html/hubbub_html_parser.rs
index 4ba46343817..9b66e4ecb1a 100644
--- a/src/components/script/html/hubbub_html_parser.rs
+++ b/src/components/script/html/hubbub_html_parser.rs
@@ -26,7 +26,6 @@ use servo_util::url::parse_url;
 use std::cast;
 use std::cell::RefCell;
 use std::comm::{Port, SharedChan};
-use std::from_str::FromStr;
 use std::str;
 use style::Stylesheet;
 
@@ -277,7 +276,8 @@ pub fn parse_html(cx: *JSContext,
 
     debug!("Fetched page; metadata is {:?}", load_response.metadata);
 
-    let url2 = load_response.metadata.final_url.clone();
+    let base_url = load_response.metadata.final_url.clone();
+    let url2 = base_url.clone();
     let url3 = url2.clone();
 
     // Store the final URL before we start parsing, so that DOM routines
@@ -485,7 +485,6 @@ pub fn parse_html(cx: *JSContext,
             // We've reached the end of a <style> so we can submit all the text to the parser.
             unsafe {
                 let style: AbstractNode = NodeWrapping::from_hubbub_node(style);
-                let url = FromStr::from_str("http://example.com/"); // FIXME
                 let mut data = ~[];
                 debug!("iterating over children {:?}", style.first_child());
                 for child in style.children() {
@@ -496,7 +495,7 @@ pub fn parse_html(cx: *JSContext,
                 }
 
                 debug!("style data = {:?}", data);
-                let provenance = InlineProvenance(url.unwrap(), data.concat());
+                let provenance = InlineProvenance(base_url.clone(), data.concat());
                 css_chan3.send(CSSTaskNewFile(provenance));
             }
         },
diff --git a/src/components/style/media_queries.rs b/src/components/style/media_queries.rs
index 06866736305..a7ed89e8230 100644
--- a/src/components/style/media_queries.rs
+++ b/src/components/style/media_queries.rs
@@ -9,6 +9,7 @@ use cssparser::ast::*;
 use errors::{ErrorLoggerIterator, log_css_error};
 use stylesheets::{CSSRule, CSSMediaRule, parse_style_rule, parse_nested_at_rule};
 use namespaces::NamespaceMap;
+use extra::url::Url;
 
 
 pub struct MediaRule {
@@ -48,7 +49,7 @@ pub struct Device {
 
 
 pub fn parse_media_rule(rule: AtRule, parent_rules: &mut ~[CSSRule],
-                        namespaces: &NamespaceMap) {
+                        namespaces: &NamespaceMap, base_url: &Url) {
     let media_queries = parse_media_query_list(rule.prelude);
     let block = match rule.block {
         Some(block) => block,
@@ -60,9 +61,9 @@ pub fn parse_media_rule(rule: AtRule, parent_rules: &mut ~[CSSRule],
     let mut rules = ~[];
     for rule in ErrorLoggerIterator(parse_rule_list(block.move_iter())) {
         match rule {
-            QualifiedRule(rule) => parse_style_rule(rule, &mut rules, namespaces),
+            QualifiedRule(rule) => parse_style_rule(rule, &mut rules, namespaces, base_url),
             AtRule(rule) => parse_nested_at_rule(
-                rule.name.to_ascii_lower(), rule, &mut rules, namespaces),
+                rule.name.to_ascii_lower(), rule, &mut rules, namespaces, base_url),
         }
     }
     parent_rules.push(CSSMediaRule(MediaRule {
diff --git a/src/components/style/properties.rs.mako b/src/components/style/properties.rs.mako
index be73277dd3d..bdd51a702a8 100644
--- a/src/components/style/properties.rs.mako
+++ b/src/components/style/properties.rs.mako
@@ -5,8 +5,11 @@
 // This file is a Mako template: http://www.makotemplates.org/
 
 use std::ascii::StrAsciiExt;
+pub use servo_util::url::parse_url;
 pub use extra::arc::Arc;
+pub use extra::url::Url;
 use servo_util::cowarc::CowArc;
+
 pub use cssparser::*;
 pub use cssparser::ast::*;
 
@@ -48,7 +51,9 @@ STYLE_STRUCTS = []
 THIS_STYLE_STRUCT = None
 LONGHANDS = []
 LONGHANDS_BY_NAME = {}
+LONGHANDS_WITH_URL = []
 SHORTHANDS = []
+SHORTHANDS_WITH_URL = []
 
 def new_style_struct(name, is_inherited):
     global THIS_STYLE_STRUCT
@@ -101,6 +106,32 @@ pub mod longhands {
         }
     </%def>
 
+    <%def name="url_longhand(name, no_super=False)">
+    <%
+        property = Longhand(name)
+        THIS_STYLE_STRUCT.longhands.append(property)
+        LONGHANDS_WITH_URL.append(property)
+        LONGHANDS_BY_NAME[name] = property
+    %>
+        pub mod ${property.ident} {
+            % if not no_super:
+                use super::*;
+            % endif
+            pub use self::computed_value::*;
+            ${caller.body()}
+
+            pub fn parse_declared(input: &[ComponentValue], base_url: &Url)
+                               -> Option<DeclaredValue<SpecifiedValue>> {
+                match CSSWideKeyword::parse(input) {
+                    Some(Some(keyword)) => Some(CSSWideKeyword(keyword)),
+                    Some(None) => Some(CSSWideKeyword(${
+                        "Inherit" if THIS_STYLE_STRUCT.inherited else "Initial"})),
+                    None => parse_specified(input, base_url),
+                }
+            }
+        }
+    </%def>
+
     <%def name="longhand(name, no_super=False)">
         <%self:raw_longhand name="${name}">
             ${caller.body()}
@@ -470,10 +501,44 @@ pub mod longhands {
     // CSS 2.1, Section 14 - Colors and Backgrounds
 
     ${new_style_struct("Background", is_inherited=False)}
-
     ${predefined_type("background-color", "CSSColor",
                       "RGBA(RGBA { red: 0., green: 0., blue: 0., alpha: 0. }) /* transparent */")}
 
+    <%self:url_longhand name="background-image">
+            // The computed value is the same as the specified value.
+            pub use to_computed_value = super::computed_as_specified;
+            pub mod computed_value {
+                pub use extra::url::Url;
+                pub type T = Option<Url>;
+            }
+            pub type SpecifiedValue = computed_value::T;
+            #[inline] pub fn get_initial_value() -> SpecifiedValue {
+                None
+            }
+            pub fn parse(input: &[ComponentValue], base_url: &Url) -> Option<SpecifiedValue> {
+                from_iter(input.skip_whitespace(), base_url)
+            }
+            pub fn from_iter<'a>(mut iter: SkipWhitespaceIterator<'a>, base_url: &Url) -> Option<SpecifiedValue> {
+                match iter.next() {
+                    Some(v) => from_component_value_with_url(v, base_url),
+                    _ => None
+                }
+            }
+            pub fn from_component_value_with_url(component_value: &ComponentValue, base_url: &Url) -> Option<SpecifiedValue> {
+                match component_value {
+                    &ast::URL(ref url) => {
+                        let image_url = parse_url(url.as_slice(), Some(base_url.clone()));
+                        Some(Some(image_url))
+                    },
+                    _ => None,
+                }
+            }
+            pub fn parse_specified(input: &[ComponentValue], base_url: &Url)
+                               -> Option<DeclaredValue<SpecifiedValue>> {
+                parse(input, base_url).map(super::SpecifiedValue)
+            }
+    </%self:url_longhand>
+
 
     ${new_style_struct("Color", is_inherited=True)}
 
@@ -782,6 +847,24 @@ pub mod shorthands {
         }
     </%def>
 
+    <%def name="url_shorthand(name, sub_properties)">
+    <%
+        shorthand = Shorthand(name, sub_properties.split())
+        SHORTHANDS_WITH_URL.append(shorthand)
+    %>
+        pub mod ${shorthand.ident} {
+            use super::*;
+
+            struct Longhands {
+                % for sub_property in shorthand.sub_properties:
+                    ${sub_property.ident}: Option<${sub_property.ident}::SpecifiedValue>,
+                % endfor
+            }
+            pub fn parse(input: &[ComponentValue], base_url: &Url) -> Option<Longhands> {
+                ${caller.body()}
+            }
+        }
+    </%def>
     <%def name="four_sides_shorthand(name, sub_property_pattern, parser_function)">
         <%self:shorthand name="${name}" sub_properties="${
                 ' '.join(sub_property_pattern % side
@@ -809,13 +892,31 @@ pub mod shorthands {
         </%self:shorthand>
     </%def>
 
-
     // TODO: other background-* properties
-    <%self:shorthand name="background" sub_properties="background-color">
-        one_component_value(input).and_then(specified::CSSColor::parse).map(|color| {
-            Longhands { background_color: Some(color) }
-        })
-    </%self:shorthand>
+    <%self:url_shorthand name="background" sub_properties="background-color background-image">
+                let mut color = None;
+                let mut image = None;
+                let mut any = false;
+
+                for component_value in input.skip_whitespace() {
+                    if color.is_none() {
+                        match background_color::from_component_value(component_value) {
+                            Some(v) => { color = Some(v); any = true; continue },
+                            None => ()
+                        }
+                    }
+
+                    if image.is_none() {
+                        match background_image::from_component_value_with_url(component_value, base_url) {
+                            Some(v) => { image = Some(v); any = true; continue },
+                            None => (),
+                        }
+                    }
+                    return None;
+                }
+                if any { Some(Longhands { background_color: color, background_image: image }) }
+                else { None }
+    </%self:url_shorthand>
 
     ${four_sides_shorthand("margin", "margin-%s", "margin_top::from_component_value")}
     ${four_sides_shorthand("padding", "padding-%s", "padding_top::from_component_value")}
@@ -973,12 +1074,12 @@ pub struct PropertyDeclarationBlock {
 }
 
 
-pub fn parse_style_attribute(input: &str) -> PropertyDeclarationBlock {
-    parse_property_declaration_list(tokenize(input))
+pub fn parse_style_attribute(input: &str, base_url: &Url) -> PropertyDeclarationBlock {
+    parse_property_declaration_list(tokenize(input), base_url)
 }
 
 
-pub fn parse_property_declaration_list<I: Iterator<Node>>(input: I) -> PropertyDeclarationBlock {
+pub fn parse_property_declaration_list<I: Iterator<Node>>(input: I, base_url: &Url) -> PropertyDeclarationBlock {
     let mut important = ~[];
     let mut normal = ~[];
     for item in ErrorLoggerIterator(parse_declaration_list(input)) {
@@ -988,7 +1089,7 @@ pub fn parse_property_declaration_list<I: Iterator<Node>>(input: I) -> PropertyD
             Declaration(Declaration{ location: l, name: n, value: v, important: i}) => {
                 // TODO: only keep the last valid declaration for a given name.
                 let list = if i { &mut important } else { &mut normal };
-                match PropertyDeclaration::parse(n, v, list) {
+                match PropertyDeclaration::parse(n, v, list, base_url) {
                     UnknownProperty => log_css_error(l, format!(
                         "Unsupported property: {}:{}", n, v.iter().to_css())),
                     InvalidValue => log_css_error(l, format!(
@@ -1036,6 +1137,9 @@ pub enum PropertyDeclaration {
     % for property in LONGHANDS:
         ${property.ident}_declaration(DeclaredValue<longhands::${property.ident}::SpecifiedValue>),
     % endfor
+    % for property in LONGHANDS_WITH_URL:
+        ${property.ident}_declaration(DeclaredValue<longhands::${property.ident}::SpecifiedValue>),
+    % endfor
 }
 
 
@@ -1045,9 +1149,11 @@ enum PropertyDeclarationParseResult {
     ValidDeclaration,
 }
 
+
 impl PropertyDeclaration {
     pub fn parse(name: &str, value: &[ComponentValue],
-                 result_list: &mut ~[PropertyDeclaration]) -> PropertyDeclarationParseResult {
+                 result_list: &mut ~[PropertyDeclaration],
+                 base_url: &Url) -> PropertyDeclarationParseResult {
         // FIXME: local variable to work around Rust #10683
         let name_lower = name.to_ascii_lower();
         match name_lower.as_slice() {
@@ -1059,6 +1165,14 @@ impl PropertyDeclaration {
                     }
                 )),
             % endfor
+            % for property in LONGHANDS_WITH_URL:
+                "${property.name}" => result_list.push(${property.ident}_declaration(
+                    match longhands::${property.ident}::parse_declared(value, base_url) {
+                        Some(value) => value,
+                        None => return InvalidValue,
+                    }
+                )),
+            % endfor
             % for shorthand in SHORTHANDS:
                 "${shorthand.name}" => match CSSWideKeyword::parse(value) {
                     Some(Some(keyword)) => {
@@ -1091,6 +1205,38 @@ impl PropertyDeclaration {
                     }
                 },
             % endfor
+            % for shorthand in SHORTHANDS_WITH_URL:
+                "${shorthand.name}" => match CSSWideKeyword::parse(value) {
+                    Some(Some(keyword)) => {
+                        % for sub_property in shorthand.sub_properties:
+                            result_list.push(${sub_property.ident}_declaration(
+                                CSSWideKeyword(keyword)
+                            ));
+                        % endfor
+                    },
+                    Some(None) => {
+                        % for sub_property in shorthand.sub_properties:
+                            result_list.push(${sub_property.ident}_declaration(
+                                CSSWideKeyword(${
+                                    "Inherit" if sub_property.style_struct.inherited else "Initial"})
+                            ));
+                        % endfor
+                    },
+                    None => match shorthands::${shorthand.ident}::parse(value, base_url) {
+                        Some(result) => {
+                            % for sub_property in shorthand.sub_properties:
+                                result_list.push(${sub_property.ident}_declaration(
+                                    match result.${sub_property.ident} {
+                                        Some(value) => SpecifiedValue(value),
+                                        None => CSSWideKeyword(Initial),
+                                    }
+                                ));
+                            % endfor
+                        },
+                        None => return InvalidValue,
+                    }
+                },
+            % endfor
             _ => return UnknownProperty,
         }
         ValidDeclaration
diff --git a/src/components/style/stylesheets.rs b/src/components/style/stylesheets.rs
index 0b5b1406457..6c66b707022 100644
--- a/src/components/style/stylesheets.rs
+++ b/src/components/style/stylesheets.rs
@@ -75,7 +75,7 @@ impl Stylesheet {
             match rule {
                 QualifiedRule(rule) => {
                     next_state = STATE_BODY;
-                    parse_style_rule(rule, &mut rules, &namespaces)
+                    parse_style_rule(rule, &mut rules, &namespaces, &base_url)
                 },
                 AtRule(rule) => {
                     let lower_name = rule.name.to_ascii_lower();
@@ -112,7 +112,7 @@ impl Stylesheet {
                         },
                         _ => {
                             next_state = STATE_BODY;
-                            parse_nested_at_rule(lower_name, rule, &mut rules, &namespaces)
+                            parse_nested_at_rule(lower_name, rule, &mut rules, &namespaces, &base_url)
                         },
                     }
                 },
@@ -125,14 +125,14 @@ impl Stylesheet {
 
 
 pub fn parse_style_rule(rule: QualifiedRule, parent_rules: &mut ~[CSSRule],
-                        namespaces: &NamespaceMap) {
+                        namespaces: &NamespaceMap, base_url: &Url) {
     let QualifiedRule{location: location, prelude: prelude, block: block} = rule;
     // FIXME: avoid doing this for valid selectors
     let serialized = prelude.iter().to_css();
     match selectors::parse_selector_list(prelude, namespaces) {
         Some(selectors) => parent_rules.push(CSSStyleRule(StyleRule{
             selectors: selectors,
-            declarations: properties::parse_property_declaration_list(block.move_iter())
+            declarations: properties::parse_property_declaration_list(block.move_iter(), base_url)
         })),
         None => log_css_error(location, format!(
             "Invalid/unsupported selector: {}", serialized)),
@@ -142,9 +142,9 @@ pub fn parse_style_rule(rule: QualifiedRule, parent_rules: &mut ~[CSSRule],
 
 // lower_name is passed explicitly to avoid computing it twice.
 pub fn parse_nested_at_rule(lower_name: &str, rule: AtRule,
-                            parent_rules: &mut ~[CSSRule], namespaces: &NamespaceMap) {
+                            parent_rules: &mut ~[CSSRule], namespaces: &NamespaceMap, base_url: &Url) {
     match lower_name {
-        "media" => parse_media_rule(rule, parent_rules, namespaces),
+        "media" => parse_media_rule(rule, parent_rules, namespaces, base_url),
         _ => log_css_error(rule.location, format!("Unsupported at-rule: @{:s}", lower_name))
     }
 }
diff --git a/src/test/html/background.html b/src/test/html/background.html
new file mode 100644
index 00000000000..c3bb0df99ab
--- /dev/null
+++ b/src/test/html/background.html
@@ -0,0 +1,20 @@
+<!DOCTYPE html>
+<html>
+	<head>
+		<title></title>
+	</head>
+	<style>
+		.test { background: url(rust-0.png) gray; }
+	</style>
+	<body>
+	    <div class="test" style="width:200px; height:200px; color:red;">
+	        background: url(rust-0.png) gray; width:200px; height:200px;
+	    </div>
+	    <div class="test" style="background-image: url(rust-45.png); width:200px; height:200px; color:red;">
+	        background-image: url(rust-45.png); width:200px; height:200px;
+	    </div>
+	    <div style="background: url(rust-90.png) yellow; width:200px; height:200px; border: 5px solid #000; color:blue;">
+	        background: url(rust-90.png) yellow; width:200px; height:200px; border: 5px solid #000;
+	    </div>
+	</body>
+</html>
diff --git a/src/test/ref/background_a.html b/src/test/ref/background_a.html
new file mode 100644
index 00000000000..28bc8f6b21d
--- /dev/null
+++ b/src/test/ref/background_a.html
@@ -0,0 +1,9 @@
+<!DOCTYPE html>
+<html>
+<head>
+<title></title>
+</head>
+<body>
+<div class="test" style="background: url(rust-0.png); width:200px; height:200px;"></div>
+</body>
+</html>
diff --git a/src/test/ref/background_b.html b/src/test/ref/background_b.html
new file mode 100644
index 00000000000..11faa177fb7
--- /dev/null
+++ b/src/test/ref/background_b.html
@@ -0,0 +1,9 @@
+<!DOCTYPE html>
+<html>
+<head>
+<title></title>
+</head>
+<body>
+<img class="test" src="rust-0.png" style="width:200px; height:200px;" />
+</body>
+</html>
diff --git a/src/test/ref/basic.list b/src/test/ref/basic.list
index 290a00741ca..bfd262afecb 100644
--- a/src/test/ref/basic.list
+++ b/src/test/ref/basic.list
@@ -29,3 +29,4 @@
 == position_relative_a.html position_relative_b.html
 == attr_exists_selector.html attr_exists_selector_ref.html
 == data_img_a.html data_img_b.html
+== background_a.html background_b.html
diff --git a/src/test/ref/rust-0.png b/src/test/ref/rust-0.png
new file mode 100644
index 00000000000..20d93badf5e
--- /dev/null
+++ b/src/test/ref/rust-0.png