/* $This file is distributed under the terms of the license in LICENSE$ */

package freemarker.ext.dump;

import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import freemarker.core.Environment;
import freemarker.template.SimpleScalar;
import freemarker.template.TemplateDirectiveBody;
import freemarker.template.TemplateException;
import freemarker.template.TemplateModel;
import freemarker.template.TemplateModelException;

public class DumpDirective extends BaseDumpDirective {

    @SuppressWarnings("unused")
    private static final Log log = LogFactory.getLog(DumpDirective.class);

    @SuppressWarnings("rawtypes")
    @Override
    public void execute(Environment env, Map params, TemplateModel[] loopVars,
            TemplateDirectiveBody body) throws TemplateException, IOException {

        if (loopVars.length != 0) {
            throw new TemplateModelException(
                "The dump directive doesn't allow loop variables.");
        }
        if (body != null) {
            throw new TemplateModelException(
                "The dump directive doesn't allow nested content.");
        }

        Object o = params.get("var");

        if ( o == null) {
            throw new TemplateModelException(
                "Must specify 'var' argument.");
        }

        if ( !(o instanceof SimpleScalar)) {
            throw new TemplateModelException(
               "Value of parameter 'var' must be a string.");
        }

        String varName = o.toString(); //((SimpleScalar)o).getAsString();
        Map<String, Object> map = getTemplateVariableDump(varName, env);
        String title = "Template variable dump";
        dump(map, env, title);
    }

    @Override
    public Map<String, Object> help(String name) {
        Map<String, Object> map = new LinkedHashMap<String, Object>();

        map.put("effect", "Dumps the contents of a template variable.");

        Map<String, String> params = new HashMap<String, String>();
        params.put("var", "name of variable to dump");
        map.put("parameters", params);

        List<String> examples = new ArrayList<String>();
        examples.add("<@" + name + " var=\"urls\" />");
        map.put("examples", examples);

        return map;

    }
}
