NotEnoughItems/src/codechicken/nei/TextField.java

package codechicken.nei;

import net.minecraft.client.gui.GuiScreen;
import net.minecraft.util.ChatAllowedCharacters;
import org.lwjgl.input.Keyboard;

import static codechicken.lib.gui.GuiDraw.*;

public abstract class TextField extends Widget
{
    public TextField(String ident)
    {
        identifier = ident;
    }
    
    public int getTextColour()
    {
        return focused() ? 0xFFE0E0E0 : 0xFF909090;
    }
    
    public void drawBox()
    {
        drawRect(x, y, width, height, 0xffA0A0A0);
        drawRect(x + 1, y + 1, width - 2, height - 2, 0xFF000000);
    }

    @Override
    public void draw(int mousex, int mousey)
    {
        drawBox();
        
        String drawtext = text;
        
        if(text.length() > getMaxTextLength())
        {
            int startOffset = drawtext.length() - getMaxTextLength();
            if(startOffset < 0 || startOffset > drawtext.length())
                startOffset = 0;
            drawtext = drawtext.substring(startOffset);
        }
        
        if(focused() && (cursorCounter / 6) % 2 == 0)
            drawtext = drawtext + '_';
        
        int textWidth = getStringWidth(text);
        int textx = centered ? x+(width-textWidth)/2 : x + 4;
        int texty = y + (height + 1) / 2 - 3;
        
        drawString(drawtext, textx, texty, getTextColour());
    }

    @Override
    public void onGuiClick(int mousex, int mousey)
    {
        if(!contains(mousex, mousey))
            setFocus(false);
    }

    @Override
    public boolean handleClick(int mousex, int mousey, int button)
    {
        if(button == 1)
            setText("");
        setFocus(true);
        return true;
    }

    @Override
    public boolean handleKeyPress(int keyID, char keyChar)
    {
        if(!focused())
            return false;
        
        if(keyID == Keyboard.KEY_BACK)
        {
            if(text.length() > 0)
            {
                setText(text.substring(0, text.length() - 1));
                backdowntime = System.currentTimeMillis();
            }
        }
        else if(keyID == Keyboard.KEY_RETURN || keyID == Keyboard.KEY_ESCAPE)
        {
            setFocus(false);
            onExit();
        }    
        else if(keyChar == 22)//paste
        {
            String pastestring = GuiScreen.getClipboardString();
            if(pastestring == null) 
                pastestring = "";
            
            if(isValid(text + pastestring))
                setText(text + pastestring);
        }
        else if(isValid(text+keyChar)) 
            setText(text+keyChar);
        
        return true;
    }
    
    public void onExit()
    {
    }

    public abstract void onTextChange(String oldText);

    public boolean isValid(String string)
    {
        // Solve the problem that Minecraft can't post Chinese characters
        return ChatAllowedCharacters.isAllowedCharacter(string.charAt(string.length()-1));
    }

    @Override
    public void update()
    {
        cursorCounter++;
        if(backdowntime > 0)
        {
            if(Keyboard.isKeyDown(Keyboard.KEY_BACK) && text.length() > 0)
            {
                if(System.currentTimeMillis() - backdowntime > 200 / (1+backs * 0.3F))
                {
                    setText(text.substring(0, text.length() - 1));
                    backdowntime = System.currentTimeMillis();
                    backs++;
                }
            }
            else
            {
                backdowntime = 0;
                backs = 0;
            }
        }
    }
    
    public void setText(String s)
    {
        String oldText = text;
        text = filterText(s);
        onTextChange(oldText);
    }
    
    public String filterText(String s)
    {
        return s;
    }
    
    private int getMaxTextLength()
    {
        return width / 6 - 2;
    }
    
    public void setFocus(boolean focus)
    {
        if(focus)
        {
            LayoutManager.setInputFocused(this);
        }
        else if(focused())
        {
            LayoutManager.setInputFocused(null);
        }
    }
    
    public boolean focused()
    {
        return LayoutManager.getInputFocused() == this;
    }
    
    public String text()
    {
        return text;
    }

    private String text = "";
    public boolean centered;
    public long backdowntime;
    public int backs;
    public String identifier;
    public int cursorCounter;
}