refactor all components and isolated from ART dependency

lib/extractFill.js

@@ -0,0 +1,82 @@
+import rgba from './rgba';
+import extractBrush from './extractBrush';
+import {
+    ART
+} from 'react-native';
+
+let {
+    LinearGradient,
+    RadialGradient
+    } = ART;
+
+let fillPatterns = {};
+let fillReg = /^url\(#(\w+?)\)$/;
+
+function isGradient(obj) {
+    return obj instanceof LinearGradient || obj instanceof RadialGradient;
+}
+
+function set(id, pattern) {
+    fillPatterns[id] = pattern;
+}
+
+function remove(id) {
+    delete fillPatterns[id];
+}
+
+function fillFilter(props) {
+    let {fill} = props;
+
+    if (fill === 'none') {
+        return null;
+    } if (fill) {
+
+        if (isGradient(fill)) {
+            return fill;
+        }
+
+        let fillOpacity = +props.fillOpacity;
+        if (isNaN(fillOpacity)) {
+            fillOpacity = 1;
+        }
+
+        // 尝试匹配 fill="url(#pattern)"
+        let matched = fill.match(fillReg);
+
+        if (matched) {
+            let patternName = `${matched[1]}:${props.svgId}`;
+            let pattern = fillPatterns[patternName];
+            
+            if (pattern) {
+                if (pattern.length === 2) {
+                    let dimensions = this.getBoundingBox();
+                    return pattern(dimensions, fillOpacity);
+                } else {
+                    return pattern(fillOpacity);
+                }
+            }
+            return null;
+        }
+
+        return rgba(props.fill, fillOpacity).rgbaString();
+    } else if (props.fill === undefined) {
+        let fillOpacity = +props.fillOpacity;
+        if (isNaN(fillOpacity)) {
+            fillOpacity = 1;
+        }
+        return rgba('#000', fillOpacity).rgbaString();
+    } else {
+        return null;
+    }
+
+}
+
+export default function(props) {
+    let fill = fillFilter.call(this, props);
+    return extractBrush(fill, props);
+}
+
+export {
+    set,
+    remove
+}