Js2/towers of honey

03week/towersOfHanoi.js

@@ -1,5 +1,5 @@
 'use strict';
-
+// assert libary is used for testing
 const assert = require('assert');
 const readline = require('readline');
 const rl = readline.createInterface({
@@ -19,23 +19,87 @@ function printStacks() {
   console.log("c: " + stacks.c);
 }
 
-function movePiece() {
-  // Your code here
 
-}
 
-function isLegal() {
-  // Your code here
+/** 
+This function takes in start Stack and end Stack,and moves the top piece
+*from the corresponding starting stack to the corresponding ending stack
+* @param {*} startStack the name of the starting stack to move the piece from
+* @param {*} endStack the name of the ending stack where the moved piece should land
+*
+*/
+
+function movePiece(startStack, endStack) {
+  // Need to first select a piece by removing it from the end of the stack... sTACKS[startStack] and removing from the end. utilizing pop()
+  let startingPiece =  stacks[startStack].pop();
+  // then need to push the piece into its its new stack. at end of stack.
+  stacks[endStack].push(startingPiece);
 
-}
 
-function checkForWin() {
-  // Your code here
+}
 
+/**
+ * This function takes in the startStack name  and endStack name
+ * and returns true only if the move is legal and valid
+ * otherwise it return false
+ * @param {*} startStack 
+ * @param {*} endStack
+ */
+
+function isLegal(startStack, endStack) {
+  // need to make sure program knows which inputs are usable
+  const onlyInputs = ["a", "b", "c"];
+
+  if(onlyInputs.includes(startStack) == false || onlyInputs.includes(endStack) == false){
+    return false;
+  } 
+
+  //if the move is into an empty stack move is legal
+  if(stacks[endStack].length == 0){
+
+    return true;
+    // if the the moving piece is moving to a larger piece the move is legal 
+
+  } else if(stacks[startStack].slice(-1) < stacks[endStack].slice(-1)){
+
+    return true;
+
+  } else {
+
+    return false;
+  }
+
+}
+/**
+ * This function returns true, if the board is in a "winning state"
+ * winning state means : you restacked on either stacks b or c, biggest to smallest
+ * 
+ */
+function checkForWin() {         
+  // if both B or C are full or there array length is 4 they have won else they lost
+  if (stacks.b.length == 4 || stacks.c.length == 4){
+    console.log("You've Won!!!")
+    return true;
+  } else {
+    return false;
+  } 
 }
 
+
+ /**
+  * This function should take in 2 inputs, the start stack and end stack and process that turn for the player
+  * @param {*} startStack the stack they want to move from 
+  * @param {*} endStack  the stack they want to move too
+  * check to see if move is legal first, if move is legal "move piece", then ckeck to see if it wins print WIN
+  * 
+  */
 function towersOfHanoi(startStack, endStack) {
-  // Your code here
+  if(isLegal(startStack,endStack) == true){
+    movePiece(startStack, endStack);
+  } else {
+    console.log("illegal move or entry");
+  }
+  checkForWin();
 
 }