StyleMap.java

/**
 * Copyright (C) 2012 alanhay <alanhay99@hotmail.com>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *         http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package uk.co.certait.htmlexporter.css;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.apache.commons.lang.StringUtils;
import org.jsoup.nodes.Element;

import com.osbcp.cssparser.CSSParser;
import com.osbcp.cssparser.Rule;

/**
 * 
 * @author alanhay
 * 
 */
public class StyleMap {
	private static final String CLASS_PREFIX = ".";

	Map<String, Style> styles;
	private StyleGenerator generator;

	public StyleMap(Map<String, Style> styles) {
		this.styles = styles != null ? styles : new HashMap<String, Style>();
		generator = new StyleGenerator();
	}

	public Style getStyleForElement(Element element) {
		Style style = new Style();

		if (getStyleForTag(element) != null) {
			style = StyleMerger.mergeStyles(style, getStyleForTag(element));
		}

		if (!getStylesForClass(element).isEmpty()) {
			List<Style> classStyles = getStylesForClass(element);

			for (Style classStyle : classStyles) {
				style = StyleMerger.mergeStyles(style, classStyle);
			}
		}

		if (getInlineStyle(element) != null) {
			style = StyleMerger.mergeStyles(style, getInlineStyle(element));
		}

		return style;
	}

	private Style getStyleForTag(Element element) {
		return styles.get(element.tagName());
	}

	private List<Style> getStylesForClass(Element element) {
		List<Style> classStyles = new ArrayList<Style>();

		if (StringUtils.isNotEmpty(element.className())) {
			String[] classNames = element.className().split(" ");

			for (String className : classNames) {
				String qualifiedClassName = CLASS_PREFIX + className.trim();

				if (styles.containsKey(qualifiedClassName)) {
					classStyles.add(styles.get(qualifiedClassName));
				}
			}
		}

		return classStyles;
	}

	private Style getInlineStyle(Element element) {
		Style style = null;

		if (element.hasAttr("style")) {
			List<Rule> inlineRules;
			try {
				String inlineStyle = element.attr("style").endsWith(";") ? element.attr("style") : element
						.attr("style") + ";";
				inlineRules = CSSParser.parse("x{" + inlineStyle + "}");
			} catch (Exception e) {
				throw new RuntimeException("Error parsing inline style for element " + element.tagName());
			}

			style = generator.createStyle(inlineRules.get(0), inlineRules.get(0).getSelectors().get(0));
		}

		return style;
	}
}