package pt.ist.fenixWebFramework.renderers;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;

import org.apache.commons.collections.Predicate;

import pt.ist.fenixWebFramework.renderers.components.HtmlComponent;
import pt.ist.fenixWebFramework.renderers.components.HtmlFormComponent;
import pt.ist.fenixWebFramework.renderers.components.HtmlHiddenField;
import pt.ist.fenixWebFramework.renderers.components.HtmlInlineContainer;
import pt.ist.fenixWebFramework.renderers.components.HtmlMenu;
import pt.ist.fenixWebFramework.renderers.components.HtmlMenuOption;
import pt.ist.fenixWebFramework.renderers.components.HtmlSimpleValueComponent;
import pt.ist.fenixWebFramework.renderers.components.HtmlTextInput;
import pt.ist.fenixWebFramework.renderers.contexts.InputContext;
import pt.ist.fenixWebFramework.renderers.converters.EnumConverter;
import pt.ist.fenixWebFramework.renderers.layouts.Layout;
import pt.ist.fenixWebFramework.renderers.model.MetaSlotKey;
import pt.ist.fenixWebFramework.renderers.utils.RenderUtils;
import pt.utl.ist.fenix.tools.util.Pair;

/**
 * This renderer presents an html menu with one option for each possible enum
 * value. Each option's label is searched in the bundle
 * <tt>ENUMERATION_RESOURCES</tt> using the enum's name.
 * 
 * <p>
 * Example:<br/> Choose a {@link java.lang.annotation.ElementType element type}:
 * <select> <option>Type</option> <option>Field</option>
 * <option>Parameter</option> <option>Constructor</option> <option>Local
 * Variable</option> <option>Annotation</option> <option>Package</option>
 * </select>
 * 
 * @author cfgi
 */
public class EnumInputRenderer extends InputRenderer {

    private String defaultText;

    private String defaultTextBundle;

    private boolean defaultOptionHidden = false;

    private String bundle;

    private boolean key;

    private String excludedValues;

    private String includedValues;

    private boolean sort;

    private boolean readOnly;

    private boolean disabled;

    public String getBundle() {
	return this.bundle;
    }

    /**
     * The bundle used if <code>key</code> is <code>true</code>
     * 
     * @property
     */
    public void setBundle(String bundle) {
	this.bundle = bundle;
    }

    public String getDefaultText() {
	return this.defaultText;
    }

    /**
     * The text or key of the default menu title.
     * 
     * @property
     */
    public void setDefaultText(String defaultText) {
	this.defaultText = defaultText;
    }

    public boolean isDefaultOptionHidden() {
	return defaultOptionHidden;
    }

    /**
     * Don't show the default option, that is, the options meaning no value
     * selected.
     * 
     * @property
     */
    public void setDefaultOptionHidden(boolean defaultOptionHidden) {
	this.defaultOptionHidden = defaultOptionHidden;
    }

    public String getExcludedValues() {
	return excludedValues;
    }

    /**
     * Excluded Values.
     * 
     * @property
     */
    public void setExcludedValues(String excludedValues) {
	this.excludedValues = excludedValues;
    }

    public String getIncludedValues() {
	return includedValues;
    }

    /**
     * Excluded Values.
     * 
     * @property
     */
    public void setIncludedValues(String includedValues) {
	this.includedValues = includedValues;
    }

    public boolean isKey() {
	return this.key;
    }

    /**
     * Indicates the the default text is a key to a resource bundle.
     * 
     * @property
     */
    public void setKey(boolean key) {
	this.key = key;
    }

    @Override
    protected Layout getLayout(Object object, Class type) {
	if (getReadOnly()) {
	    return new Layout() {
		@Override
		public HtmlComponent createComponent(Object targetObject, Class type) {
		    Enum enumerate = (Enum) targetObject;

		    HtmlInlineContainer container = new HtmlInlineContainer();
		    HtmlHiddenField value = new HtmlHiddenField();
		    value.setValue(enumerate.name());
		    value.setConverter(new EnumConverter());
		    container.addChild(value);
		    InputContext context = getInputContext();
		    ((HtmlFormComponent) value).setTargetSlot((MetaSlotKey) context.getMetaObject().getKey());

		    HtmlTextInput component = new HtmlTextInput();
		    component.setValue(RenderUtils.getEnumString(enumerate));
		    container.addChild(component);

		    return container;
		}

		@Override
		public void applyStyle(HtmlComponent component) {
		    HtmlInlineContainer block = (HtmlInlineContainer) component;
		    HtmlTextInput textInput = (HtmlTextInput) block.getChild(new Predicate() {
			@Override
			public boolean evaluate(Object elem) {
			    return !(elem instanceof HtmlHiddenField);
			}
		    });

		    super.applyStyle(textInput);
		    textInput.setReadOnly(true);
		    textInput.setDisabled(getDisabled());
		}
	    };
	}
	return new Layout() {

	    @Override
	    public HtmlComponent createComponent(Object targetObject, Class type) {
		Enum enumerate = (Enum) targetObject;

		if (!type.isEnum() && Enum.class.isAssignableFrom(type)) {
		    type = type.getEnclosingClass();
		}

		Collection<Object> constants = getIncludedEnumValues(type);
		Collection<Object> excludedValues = getExcludedEnumValues(type);
		List<Pair<Enum, String>> pairList = new ArrayList<Pair<Enum, String>>();

		for (Object object : constants) {
		    Enum oneEnum = (Enum) object;
		    pairList.add(new Pair<Enum, String>(oneEnum, RenderUtils.getEnumString(oneEnum, getBundle())));
		}

		if (isSort()) {
		    Collections.sort(pairList, new Comparator<Pair<Enum, String>>() {
			public int compare(Pair<Enum, String> o1, Pair<Enum, String> o2) {
			    return o1.getValue().compareTo(o2.getValue());
			}
		    });
		}

		HtmlSimpleValueComponent holderComponent = createInputContainerComponent(enumerate);

		for (Pair<Enum, String> pair : pairList) {

		    Enum oneEnum = pair.getKey();
		    String description = pair.getValue();

		    if (excludedValues.contains(oneEnum)) {
			continue;
		    }

		    addEnumElement(enumerate, holderComponent, oneEnum, description);
		}

		holderComponent.setConverter(new EnumConverter());
		holderComponent.setTargetSlot((MetaSlotKey) getInputContext().getMetaObject().getKey());

		return holderComponent;
	    }

	    @Override
	    public void applyStyle(HtmlComponent component) {
		super.applyStyle(component);

		HtmlSimpleValueComponent holderComponent = (HtmlSimpleValueComponent) component;
		holderComponent.setDisabled(getDisabled());
	    }

	};
    }

    protected void addEnumElement(Enum enumerate, HtmlSimpleValueComponent holder, Enum oneEnum, String description) {
	HtmlMenu menu = (HtmlMenu) holder;

	HtmlMenuOption option = menu.createOption(description);
	option.setValue(oneEnum.toString());

	if (enumerate != null && oneEnum.equals(enumerate)) {
	    option.setSelected(true);
	}
    }

    protected HtmlSimpleValueComponent createInputContainerComponent(Enum enumerate) {
	HtmlMenu menu = new HtmlMenu();

	if (!isDefaultOptionHidden()) {
	    String defaultOptionTitle = getDefaultTitle();
	    menu.createDefaultOption(defaultOptionTitle).setSelected(enumerate == null);
	}

	return menu;
    }

    // TODO: refactor this, probably mode to HtmlMenu, duplicate
    // id=menu.getDefaultTitle
    private String getDefaultTitle() {
	if (getDefaultText() == null) {
	    return RenderUtils.getResourceString("renderers.menu.default.title");
	} else {
	    if (isKey()) {
		return RenderUtils.getResourceString(getDefaultTextBundle(), getDefaultText());
	    } else {
		return getDefaultText();
	    }
	}
    }

    private Collection<Object> getIncludedEnumValues(Class type) {
	final String valuesString = getIncludedValues();

	if (valuesString == null || valuesString.length() == 0) {
	    Object[] constants = type.getEnumConstants();
	    if (constants == null) {
		constants = type.getDeclaringClass().getEnumConstants();
	    }

	    return Arrays.asList(constants);
	} else {
	    return getEnumValues(type, valuesString);
	}
    }

    private Collection<Object> getExcludedEnumValues(Class type) {
	final String valuesString = getExcludedValues();

	if (valuesString == null || valuesString.length() == 0) {
	    return Collections.emptyList();
	} else {
	    return getEnumValues(type, valuesString);
	}
    }

    private Collection<Object> getEnumValues(Class type, String valuesString) {
	ArrayList<Object> result = new ArrayList<Object>();
	for (String part : valuesString.split(",")) {
	    result.add(Enum.valueOf(type, part.trim()));
	}

	return result;
    }

    public boolean isSort() {
	return sort;
    }

    public void setSort(boolean sort) {
	this.sort = sort;
    }

    public boolean getDisabled() {
	return disabled;
    }

    public void setDisabled(boolean disabled) {
	this.disabled = disabled;
    }

    public boolean getReadOnly() {
	return readOnly;
    }

    public void setReadOnly(boolean readOnly) {
	this.readOnly = readOnly;
    }

    public String getDefaultTextBundle() {
	return defaultTextBundle;
    }

    public void setDefaultTextBundle(String defaultTextBundle) {
	this.defaultTextBundle = defaultTextBundle;
    }
}