/**
* putWordInSlot()
*
* <p>Puts each letter from the word it's passed into the slot it's passed, and marks the word
* USED. Also increments the positions in the letterUsage array corresponding to the slot to
* indicate that one more word is now using these letters.
*/
private void putWordInSlot(CrosswordWord w, CrosswordSpace slot) {
Point position = new Point(slot.getStart());
for (int i = 0; i < slot.getLength(); i++) {
// Put each letter from the word into this slot of
// the puzzle:
puzzle[position.x][position.y] = w.getWord().charAt(i);
// Record the fact that one more word is now using the
// letter at this position:
letterUsage[position.x][position.y]++;
// Advance to the next position in the slot:
position.x += slot.getDirection().x;
position.y += slot.getDirection().y;
}
// Mark the word as USED:
w.setUsed(true);
}
/**
* removeWordFromSlot()
*
* <p>Clears each position in the slot it's passed, but ONLY those positions containing letters
* NOT used by any other words according to the letterUsage array. Also marks the word that used
* to be in the slot as UNUSED.
*/
private void removeWordFromSlot(CrosswordWord w, CrosswordSpace slot) {
Point position = new Point(slot.getStart());
for (int i = 0; i < slot.getLength(); i++) {
// One fewer word is now using the letter at this position:
letterUsage[position.x][position.y]--;
// If no words are now using this letter, clear it:
if (letterUsage[position.x][position.y] == 0) {
puzzle[position.x][position.y] = BLANK;
}
// Advance to the next position in the slot:
position.x += slot.getDirection().x;
position.y += slot.getDirection().y;
}
// Mark the word as UNUSED -- ie., available to be placed
// elsewhere in the puzzle:
w.setUsed(false);
}
/**
* wordFitsInSlot()
*
* <p>Returns true if the word passed to it fits into the slot passed to it AND is unused,
* otherwise returns false.
*/
private boolean wordFitsInSlot(CrosswordWord w, CrosswordSpace slot) {
// If the length of the word doesn't match the length of the
// slot, or the word is already used, we can't put this word
// here and so we return false:
if (w.getWord().length() != slot.getLength() || w.isUsed()) {
return false;
}
// Otherwise we examine each position in the slot. If
// there are letters in the slot already, and those letters
// DON'T match the letters at the corresponding positions
// in our word, the word won't fit and we return false:
Point position = new Point(slot.getStart());
for (int i = 0; i < slot.getLength(); i++) {
if (puzzle[position.x][position.y] != BLANK
&& puzzle[position.x][position.y] != w.getWord().charAt(i)) {
return false;
}
// Advance to the next position in the slot:
position.x += slot.getDirection().x;
position.y += slot.getDirection().y;
}
// If we get here, it means the word is unused, the right
// length for the current slot, and its letters match any
// letters already in the slot:
return true;
}
