package com.ecyrd.jspwiki.plugin.i3g;

import java.util.Map;

import javax.servlet.jsp.JspWriter;

import org.apache.log4j.Logger;

import com.ecyrd.jspwiki.TextUtil;
import com.ecyrd.jspwiki.WikiContext;
import com.ecyrd.jspwiki.WikiEngine;
import com.ecyrd.jspwiki.WikiPage;
import com.ecyrd.jspwiki.attachment.Attachment;
import com.ecyrd.jspwiki.plugin.PluginException;
import com.ecyrd.jspwiki.plugin.WikiPlugin;

/**
 * Base class for i3g plugins, provides basic services and is a place where 
 * utility methods should go
 * 
 * @author Christoph Sauer
 */
public abstract class I3gWikiPlugin implements WikiPlugin {
	private static Logger log = Logger.getLogger(I3gWikiPlugin.class);

	/**
	 * This method is used to clean away things like quotation marks which a
	 * malicious user could use to stop processing and insert javascript. Sets
	 * defval if parameter is not present. (corresponds to getCleanParameter in other plugins)
	 */
	static final String getParameter(Map params, String paramId,
			String defval, boolean reqired) throws PluginException {
		String paramString = (String) params.get(paramId);

		if (paramString == null) {
			paramString = defval;
		} else {
			TextUtil.replaceEntities(paramString);
		}

        if( paramString == null ) {
            throw new PluginException("Parameter '"+paramId+"' is required for plugin");
        }		
		 
		return paramString;
	}

	static final String getParameter(Map params, String paramId, String defval) 
		throws PluginException {
		
		return getParameter(params, paramId, defval, false);
		 
	}
	
	static final String getLink(String pageName, String title, WikiContext context) {
		return getLink(pageName, title, context, WikiContext.VIEW);
	}
	

	// Sourcode is directly copied and adapted from LinkToTag.java
	static final String getLink(String pageName, String title, WikiContext context, String mode) {
        WikiEngine engine   = context.getEngine();
        boolean    isattachment = false;
        String version = null; // TODO: find out what parameter does, pass as parameter
        String template = null; // TODO: find out what parameter does, pass as parameter
        int format = 0; //ANCHOR TODO: pass as parameter
        
        if( pageName == null )
        {
            WikiPage p = context.getPage();

            if( p != null )
            {
                pageName = p.getName();

                isattachment = (p instanceof Attachment);
            }
            else
            {
                return "";
            }
        }

        String url;
        String linkclass;

        if( isattachment )
        {
            url = context.getURL(WikiContext.ATTACH,pageName,
                                       (version != null) ? "version="+version : null );
            linkclass = "attachment";
        }
        else
        {
            StringBuffer params = new StringBuffer();
            if( version != null ) params.append( "version="+version );
            if( template != null ) params.append( (params.length()>0?"&":"") + "skin="+template );

            url = context.getURL( mode, pageName,
                                        params.toString() );
            linkclass = "wikipage";
        }

        String out = "";
        switch( format )
        {
          case 0:
            out += "<a class=\""+linkclass+"\" href=\""+url+"\">" + title + "</a>";
            break;
          case 1:
            out += url ;
            break;
        }

        return out;

	}
	
}