import java.util.*;
import com.ecyrd.jspwiki.*;
import com.ecyrd.jspwiki.attachment.AttachmentManager;
import com.ecyrd.jspwiki.attachment.Attachment;
import com.ecyrd.jspwiki.plugin.*;
import com.ecyrd.jspwiki.providers.ProviderException;

public class IFramePlugin implements WikiPlugin
{
    public static final String PARAM_ATTACHMENT		= "attachment";
	public static final String PARAM_URL			= "url";
    public static final String PARAM_ALIGN    		= "align";
    public static final String PARAM_BORDER   		= "border";
    public static final String PARAM_WIDTH    		= "width";
    public static final String PARAM_HEIGHT   		= "height";
	public static final String PARAM_MARGINWIDTH	= "marginwidth";
	public static final String PARAM_MARGINHEIGHT	= "marginheight";
	public static final String PARAM_SCROLLING		= "scrolling";
	
    public String execute(WikiContext context, Map params) throws PluginException
    {
        WikiEngine engine = context.getEngine();
		
        String attachment	= getCleanParameter(params, PARAM_ATTACHMENT);
		String url 			= getCleanParameter(params, PARAM_URL);
        String align		= getCleanParameter(params, PARAM_ALIGN, "center").toLowerCase();
        String border		= getCleanParameter(params, PARAM_BORDER, "0");
        String width		= getCleanParameter(params, PARAM_WIDTH, "100%");
        String height		= getCleanParameter(params, PARAM_HEIGHT, "100%");
		String marginwidth  = getCleanParameter(params, PARAM_MARGINWIDTH, "10");
		String marginheight = getCleanParameter(params, PARAM_MARGINHEIGHT, "10");
		String scrolling 	= getCleanParameter(params, PARAM_SCROLLING, "auto");

        if (attachment == null && url == null)
        {
            throw new PluginException("Parameter 'attachment' or 'url' is required for the MediaPlugin to work");
        }
		
		String src = null;
		
		if (attachment != null)
		{
			try
			{
				AttachmentManager mgr = engine.getAttachmentManager();

				Attachment att = mgr.getAttachmentInfo(context, attachment);

				src = context.getURL(WikiContext.ATTACH, att.getName());
			}
			catch (ProviderException ex)
			{
				throw new PluginException("Could not resolve the attachment: " + ex.getMessage());
			}
		}
		else
		{
			if (url.startsWith("http"))
			{
				try
				{
					src = new java.net.URL(url).toExternalForm();
				}
				catch (java.net.MalformedURLException ex)
				{
					throw new PluginException("Could not resolve the url: " + ex.getMessage());
				}
			}
			else
			{
				src = url;
			}
		}

        StringBuffer result = new StringBuffer();
		
		result.append("<iframe src=\"" + src + "\" align=\"" + align + "\" frameborder=\"" + border + "\" width=\"" + width + "\" height=\"" + height + "\" marginwidth=\"" + marginwidth + "\" marginheight=\"" + marginheight + "\" scrolling=\"" + scrolling +"\">\n");
		result.append("    Your browser does not support inline frames.\n");
		result.append("</iframe>\n");

        return result.toString();
	}
	
	private static final String getCleanParameter(Map params, String paramId, String defaultValue)
	{
		String value = getCleanParameter(params, paramId);
		
		if (value == null)
		{
			value = defaultValue;
		}
		
		return value;
	}

    /**
     *  This method is used to clean away things like quotation marks which
     *  a malicious user could use to stop processing and insert javascript.
     */
    private static final String getCleanParameter(Map params, String paramId)
    {
        return TextUtil.replaceEntities((String) params.get(paramId));
    }
}