/* built with Studio Sketchpad: 
 *   https://sketchpad.cc
 * 
 * observe the evolution of this sketch: 
 *   https://studio.sketchpad.cc/sp/pad/view/ro.s0xWbQ7L2BL/rev.31
 * 
 * authors: 
 *   GoToLoop

 * license (unless otherwise specified): 
 *   creative commons attribution-share alike 3.0 license.
 *   https://creativecommons.org/licenses/by-sa/3.0/ 
 */ 



/** 
 * TextBox Writer (v2.4)
 * by  Inarts (2013/Oct)
 * mod GoToLoop
 *
 * forum.processing.org/two/discussion/423/
 * how-to-write-a-class-for-text-area-without-using-any-library
 *
 * studio.processingtogether.com/sp/pad/export/ro.9Zo$UbIWYZEDR/latest
 */

static final int NUM = 2;
final TextBox[] tboxes = new TextBox[NUM];
int idx;

void setup() {
  size(640, 480);
  frameRate(20);
  smooth(4);

  rectMode(CORNER);
  textAlign(LEFT);
  strokeWeight(1.5);

  instantiateBoxes();
  tboxes[idx = 1].isFocused = true;
}

void draw() {
  background(#778C85);
  for (int i = 0; i != NUM; tboxes[i++].display());
}

void mouseClicked() {
  int i = idx = -1;
  while (++i != NUM)  if (tboxes[i].checkFocus())  idx = i;
}

void keyTyped() {
  final char k = key;
  if (k == CODED | idx < 0)  return;

  final TextBox tbox = tboxes[idx];
  final int len = tbox.txt.length();

  if (k == BACKSPACE)  tbox.txt = tbox.txt.substring(0, max(0, len-1));
  else if (len >= tbox.lim)  return;
  else if (k == ENTER | k == RETURN)     tbox.txt += "\n";
  else if (k == TAB & len < tbox.lim-3)  tbox.txt += "    ";
  else if (k == DELETE)  tbox.txt = "";
  else if (k >= ' ')     tbox.txt += str(k);
}

void keyPressed() {
  if (key != CODED | idx < 0)  return;
  final int k = keyCode;

  final TextBox tbox = tboxes[idx];
  final int len = tbox.txt.length();

  if (k == LEFT)  tbox.txt = tbox.txt.substring(0, max(0, len-1));
  else if (k == RIGHT & len < tbox.lim-3)  tbox.txt += "    ";
}

void instantiateBoxes() {
  tboxes[0] = new TextBox(
  width>>2, height/4 + height/16, // x, y
  width - width/2, height/2 - height/4 - height/8, // w, h
  215, // lim
  0300 << 030, color(-1, 040), // textC, baseC
  color(-1, 0100), color(#FF00FF, 0200)); // bordC, slctC

  tboxes[1] = new TextBox(
  width>>3, height/2 + height/8, // x, y
  width - width/4, height - height/2 - height/4, // w, h
  640, // lim
  0300 << 030, color(-1, 040), // textC, baseC
  color(-1, 0100), color(#FFFF00, 0200)); // bordC, slctC
}

class TextBox { // demands rectMode(CORNER)
  final color textC, baseC, bordC, slctC;
  final short x, y, w, h, xw, yh, lim;

  boolean isFocused;
  String txt = "";

  TextBox(int xx, int yy, int ww, int hh, int li, 
  color te, color ba, color bo, color se) {
    x = (short) xx;
    y = (short) yy;
    w = (short) ww;
    h = (short) hh;

    lim = (short) li;

    xw = (short) (xx + ww);
    yh = (short) (yy + hh);

    textC = te;
    baseC = ba;
    bordC = bo;
    slctC = se;
  }

  void display() {
    stroke(isFocused? slctC : bordC);
    fill(baseC);
    rect(x, y, w, h);

    fill(textC);
    text(txt + blinkChar(), x, y, w, h);
  }

  String blinkChar() {
    return isFocused && (frameCount>>2 & 1) == 0 ? "_" : "";
  }

  boolean checkFocus() {
    return isFocused = mouseX > x & mouseX < xw & mouseY > y & mouseY < yh;
  }
}