package ch.ethz.globis.isk.ui;

import java.awt.Window;
import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Dimension;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.lang.reflect.Method;
import java.lang.reflect.ParameterizedType;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Vector;

import javax.swing.JFrame;
import javax.swing.ListModel;
import javax.swing.JDialog;
import javax.swing.BoxLayout;
import javax.swing.DefaultListModel;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.JSpinner;
import javax.swing.JTextField;
import javax.swing.SpinnerNumberModel;
import javax.swing.SwingUtilities;
import javax.swing.KeyStroke;
import javax.swing.AbstractAction;

import ch.ethz.globis.isk.DBManager;
import ch.ethz.globis.isk.domain.DomainObject;

public class ClassEditor extends JPanel{
    Object inst;
    ArrayList<Method> get = new ArrayList<Method>();
    ArrayList<Method> set = new ArrayList<Method>();
    ArrayList<Editor> editors = new ArrayList<Editor>();

    JButton save;

    public ClassEditor(Class view){
        this(view, null);
    }

    public ClassEditor(Object inst){
        this(inst.getClass(), inst);
    }

    public ClassEditor(Class view, Object inst){
        if(inst == null){
            try{
                inst = view.newInstance();
            }catch(Exception ex){
                // FIXME: bail
                ex.printStackTrace();
            }
        }

        this.inst = inst;
        ClassHelper.retrieveGetSet(view, get, set);
        
        setLayout(new GridBagLayout());

        int i=0;
        for(Method m : get){
            try{
                Class rettype = m.getReturnType();
                Object retvalue = m.invoke(inst);
                if(retvalue instanceof Integer){
                    addUIElement(new JLabel(m.getName().substring(3)), 0, i, 1, 0.0, 0.0);

                    IntegerEditor edit = new IntegerEditor((Integer)retvalue);
                    editors.add(edit);
                    addUIElement(edit, 1, i, 1, 1.0, 0.0);
                }else if(String.class.isAssignableFrom(rettype)){
                    addUIElement(new JLabel(m.getName().substring(3)), 0, i, 1, 0.0, 0.0);

                    StringEditor edit = new StringEditor((String)retvalue);
                    editors.add(edit);
                    addUIElement(edit, 1, i, 1, 1.0, 0.0);
                }else if(DomainObject.class.isAssignableFrom(rettype)){
                    addUIElement(new JLabel(m.getName().substring(3)), 0, i, 1, 0.0, 0.0);

                    InstanceChooser edit = new InstanceChooser(rettype, (DomainObject)retvalue);
                    editors.add(edit);
                    addUIElement(edit, 1, i, 1, 1.0, 0.0);
                }else if(Collection.class.isAssignableFrom(rettype)){
                    addUIElement(new JLabel(m.getName().substring(3)), 0, i, 2, 0.0, 0.0);

                    i++;
                    rettype = (Class)((ParameterizedType)m.getGenericReturnType()).getActualTypeArguments()[0];
                    CollectionEditor edit = new CollectionEditor(rettype, (Collection)retvalue);
                    editors.add(edit);
                    addUIElement(edit, 0, i, 2, 1.0, 0.5);
                }else{
                    throw new Exception("Unhandled value type: "+rettype);
                }
                i++;
            }catch(Exception ex){
                ex.printStackTrace();
            }
        }
        
        save = new JButton("Save");
        save.addActionListener((ev) -> save());
        addUIElement(save, 0, i, 2, 1.0, 0.0);
    }

    private void addUIElement(Container item, int x, int y, int w, double ww, double hh){
        GridBagConstraints c = new GridBagConstraints();
        c.fill = GridBagConstraints.BOTH;
        c.gridx = x; c.gridy = y;
        c.gridwidth = w; c.gridheight = 1;
        c.weightx = ww; c.weighty = hh;
        c.insets = new Insets(1, 1, 1, 1);
        add(item, c);
    }

    public void save(){
        try{
            DBManager.instance.beginTransaction();
            for(int i=0; i<editors.size(); i++){
                Editor e = editors.get(i);
                Method m = set.get(i);
                try{
                    System.out.println("Saving: "+inst.getClass().getSimpleName()+"."+m.getName()+"("+e.value()+")");
                    m.invoke(inst, e.value());
                }catch(Exception ex){
                    ex.printStackTrace();
                }
            }
            DBManager.instance.registerWithDatabase(inst);
            DBManager.instance.commitTransaction();
        }catch(Exception ex){
            ex.printStackTrace();
        }
    }

    public static void showCreator(Window parent, Class view){
        JDialog frame = new JDialog(parent, "Add a "+view.getSimpleName());
        frame.add(new ClassEditor(view), BorderLayout.CENTER);
        frame.setLocationRelativeTo(parent);
        frame.setPreferredSize(new Dimension(350, 500));
        frame.pack();
        frame.setVisible(true);
    }

    public static void showEditor(Window parent, Object view){
        JDialog frame = new JDialog(parent, "Edit "+view.getClass().getSimpleName());
        frame.add(new ClassEditor(view), BorderLayout.CENTER);
        frame.setLocationRelativeTo(parent);
        frame.setPreferredSize(new Dimension(350, 500));
        frame.pack();
        frame.setVisible(true);
    }
}

interface Editor{
    public Object value();
}

class IntegerEditor extends JPanel implements Editor{
    JSpinner value;
    public IntegerEditor(int value){
        super(new BorderLayout());
        this.value = new JSpinner(new SpinnerNumberModel(0, 0, null, 1));
        this.value.setValue(value);
        add(this.value, BorderLayout.CENTER);
    }

    public Object value(){
        return (Integer)value.getValue();
    }
}

class StringEditor extends JPanel implements Editor{
    JTextField value;
    public StringEditor(String value){
        super(new BorderLayout());
        this.value = new JTextField((value == null)?"":value);
        add(this.value, BorderLayout.CENTER);
    }

    public Object value(){
        return value.getText();
    }
}

class InstanceChooser extends JPanel implements Editor{
    JComboBox value;
    public InstanceChooser(Class view, DomainObject value){
        super(new BorderLayout());
        Collection instances = DBManager.instance.newQuery(view, "");
        this.value = new JComboBox(new Vector(instances));
        if(value != null) this.value.setSelectedItem(value);
        add(this.value, BorderLayout.CENTER);
    }

    public Object value(){
        return value.getSelectedItem();
    }
}

class CollectionEditor extends JPanel implements Editor{
    Class collectionClass;
    JList list;
    InstanceChooser chooser;
    public CollectionEditor(Class view, Collection value){
        super(new BorderLayout());
        collectionClass = value.getClass();
        DefaultListModel model = new DefaultListModel();
        for(Object o : value) model.addElement(o);
        list = new JList(model);
        chooser = new InstanceChooser(view, null);
        list.addMouseListener(new MouseAdapter(){
                public void mouseClicked(MouseEvent ev){
                    if(ev.getClickCount() == 2) editObject(list.getSelectedValue());
                }
            });
        list.getInputMap().put(KeyStroke.getKeyStroke("DELETE"), "deleteRow");
        list.getActionMap().put("deleteRow", new AbstractAction() {
                public void actionPerformed(ActionEvent ev){
                    removeObject(list.getSelectedValue());
                }
            });
        JPanel bottom = new JPanel();
        bottom.setLayout(new BoxLayout(bottom, BoxLayout.LINE_AXIS));
        JButton button = new JButton("+");
        button.addActionListener((ev) -> addNewObject(chooser.value()));
        bottom.add(chooser);
        bottom.add(button);
        add(list, BorderLayout.CENTER);
        add(bottom, BorderLayout.SOUTH);
    }

    private void removeObject(Object o){
        ((DefaultListModel)list.getModel()).removeElement(o);
    }

    private void editObject(Object o){
        ClassEditor.showEditor((Window)SwingUtilities.getWindowAncestor(this), o);
    }

    private void addNewObject(Object o){
        ((DefaultListModel)list.getModel()).addElement(o);
    }

    public Object value(){
        ListModel model = list.getModel();
        try{
            Collection result = (Collection) collectionClass.newInstance();
            
            for(int i=0; i < model.getSize(); i++){
                result.add(model.getElementAt(i));
            }
            
            return result;
        }catch(Exception ex){
            ex.printStackTrace();
            return null;
        }
    }
}