Terminal.java

package kpc.common.computer;

import kpc.common.utils.INBTTaggable;
import net.minecraft.nbt.NBTTagCompound;

import java.util.Arrays;

public final class Terminal
implements INBTTaggable,
           kpc.api.computer.Terminal{
    public final int width;
    public final int height;

    private int cursorX;
    private int cursorY;
    private int bgColor;
    private int fgColor;
    private boolean cursorBlink;
    private String empty;
    private String[] lines;

    public Terminal(){
        this(60, 19);
    }

    public Terminal(int width, int height) {
        this.width = width;
        this.height = height;

        this.cursorX = 0;
        this.cursorY = 0;
        this.cursorBlink = false;
        this.fgColor = 0xFFFFFF;
        this.bgColor = 0x111111;
        this.lines = new String[this.height];

        this.buildEmpty();
    }

    public void clearLine(){
        this.lines[this.cursorY] = this.empty;
    }

    @Override
    public int getHeight() {
        return this.height;
    }

    @Override
    public int getWidth() {
        return this.width;
    }

    public int getBackgroundColor(){
        return this.bgColor;
    }

    public int getForegroundColor(){
        return this.fgColor;
    }

    public void setBackgroundColor(int bg){
        this.bgColor = bg;
    }

    public void setForegroundColor(int fg){
        this.fgColor = fg;
    }

    private void buildEmpty(){
        char[] spaces = new char[width];
        Arrays.fill(spaces, ' ');
        this.empty = new String(spaces);
        for (int i = 0; i < this.height; i++) {
            this.lines[i] = this.empty;
        }
    }

    public void setCursorPos(int x, int y){
        if((this.cursorX != x) || (this.cursorY != y)){
            this.cursorX = x;
            this.cursorY = y;

            if(this.cursorX < 0){
                this.cursorX = 0;
            } else if(this.cursorX > this.width){
                this.cursorX = this.width;
            }

            if(this.cursorY < 0){
                this.cursorY = 0;
            } else if(this.cursorY > this.height){
                this.cursorY = this.height;
            }
        }
    }

    public void setCursorBlink(boolean blink){
        if(this.cursorBlink != blink){
            this.cursorBlink = blink;
        }
    }

    public int getCursorX(){
        return this.cursorX;
    }

    public int getCursorY(){
        return this.cursorY;
    }

    public boolean getCursorBlink(){
        return this.cursorBlink;
    }

    public void backspace(){
        if(this.cursorX >= 1 && this.cursorY < this.height){
            this.lines[this.cursorY] = this.lines[this.cursorY].substring(0, this.cursorX - 1) + " " + this.lines[this.cursorY].substring(this.cursorX + 1);
        }
    }

    public void write(String line){
        try{
            if((this.cursorX >= 0 && this.cursorY < this.height)){
                int writeX = this.cursorX;
                int spaceLeft = this.width - this.cursorX;
                if(spaceLeft > this.width + line.length()){
                    return;
                }

                if(spaceLeft > this.width){
                    writeX = 0;
                    line = line.substring(spaceLeft - this.width);
                    spaceLeft = this.width;
                }

                line = line.replace("\t", " ");
                if(spaceLeft > 0){
                    String oldLine = this.lines[this.cursorY];
                    StringBuilder newLine = new StringBuilder();
                    newLine.append(oldLine.substring(0, writeX));

                    if(line.length() < spaceLeft){
                        newLine.append(line);
                        newLine.append(oldLine.substring(writeX + line.length()));
                    } else{
                        newLine.append(line.substring(0, spaceLeft));
                    }

                    this.lines[this.cursorY] = newLine.toString();
                }
            }
        } catch(Exception e){
            e.printStackTrace(System.err);
        }
    }

    public void scroll(int dY){
        String[] newLines = new String[this.height];
        for(int y = 0; y < this.height; y++){
            int oldY = y + dY;
            if((oldY >= 0) && (oldY < this.height)){
                newLines[y] = this.lines[oldY];
            } else{
                newLines[y] = this.empty;
            }
        }
        this.lines = newLines;
    }

    public void clear(){
        for(int y = 0; y < this.height; y++){
            if(!this.lines[y].equals(this.empty)){
                this.lines[y] = this.empty;
            }
        }
    }

    public String getLine(int y){
        if((y >= 0) && (y < this.height)){
            return this.lines[y];
        }

        return "<error>";
    }

    @Override
    public void readFromNBT(NBTTagCompound comp) {
        this.cursorX = comp.getInteger("cursorX");
        this.cursorY = comp.getInteger("cursorY");
        this.fgColor = comp.getInteger("fgColor");
        this.bgColor = comp.getInteger("bgColor");
        this.cursorBlink = comp.getBoolean("cursorBlink");
        for(int i = 0; i < this.height; i++){
            this.lines[i] = comp.getString("line_" + i);
        }
    }

    @Override
    public void writeToNBT(NBTTagCompound comp) {
        comp.setInteger("cursorX", this.cursorX);
        comp.setInteger("cursorY", this.cursorY);
        comp.setInteger("fgColor", this.fgColor);
        comp.setInteger("bgColor", this.bgColor);
        comp.setBoolean("cursorBlink", this.cursorBlink);
        for(int i = 0; i < this.height; i++){
            comp.setString("line_" + i, this.lines[i]);
        }
    }
}