import random

# Author:  James Tam
# Version: Fall, 2022

"""
 New learning objective:
 * Boundary checking using named constants.
 * Defining and using a Boolean function for boundary checking.
"""
SIZE = 4
FIELD = " "
FOREST = "^"
WATER = "W"
BURNT = "F"
ERROR = "!"

"""
   @ display()
   @ argument: 2D list of char(length 1 string), simulated game
     world
   @ return value: none
   @ 
   @ Shows the current state of the world
"""
def display(world):
   r = -1
   c = -1
   for r in range (0,SIZE,1):
      for c in range (0,SIZE,1):
         print(world[r][c], end="")
      print()
   print()

"""
   @ editLocation
   @ editLocation(int,int,2DList reference)
   @ returns(nothing)
   @ Changes the selected location to an exclaimation mark
 
"""
def editLocation(row,column,world):
   world[row][column] = "!"

"""
   @ generateElemement
   @ a random number argument (precondition 1<=number<=100)
   @ returns a string of length one (an element to populate
     world
"""
def generateElement(randomNumber):
    element = ERROR
    if ((randomNumber >= 1) and (randomNumber <= 50)):
        element = FIELD
    elif ((randomNumber >= 51) and (randomNumber <= 80)):
        element = FOREST
    elif ((randomNumber >= 81) and (randomNumber <= 100)):
        element = WATER
    else:
        element = ERROR
    return(element)

"""
   @ getLocation
   @ getLocation(nothing)
   @ returns(int,int)
   @ Prompts the user for a given location(row,column)
"""
def getLocation():
    outOfBounds = True
    row = -1
    column = -1
    while (outOfBounds == True):
       print("Enter location of square to change to a !")
       row = int(input("Enter a row (0-3): "))
       column = int(input("Enter a column (0-3): "))
       outside = isOut(row,column)
       if (outside == True):
          print("Row=%d, Col=%d" %(row,column), end = " ")
          print("is outside range of 0-" + str(SIZE) + "." )
       else:
          outOfBounds = False
    return(row,column)
  
def initialize():
    world = []
    r = -1
    c = -1
    randomNumber = -1
    newElement = ERROR
    for r in range (0,SIZE,1):
        randomNumber = random.randrange(1,101)
        element = generateElement(randomNumber)
        tempRow = [element] * SIZE
        world.append(tempRow)  # Add in new empty row
        print(tempRow)
    return(world)

"""
   @ isOut
   @ isOut(int,int)
   @ returns(Boolean)
   @for a given location(row,column) function determines if the location is within
    the list bounds. 
"""
def isOut(row,column):
    outside = False
    if ((row < 0) or \
        (row >= SIZE) or \
        (column < 0) or \
        (column >= SIZE)):
        outside = True
    return(outside)


# MAIN EXECUTION POINT
def start():
    stillRunning = True
    answer = ""
    row = -1
    column = -1
    world = initialize()
    while(stillRunning): #while(stillRunning == True):
        display(world)
        row,column = getLocation()
        editLocation(row,column,world)
        answer = input("Hit enter to continue,'q' to quit: ")
        if ((answer == "q") or (answer == "Q")):
            stillRunning = False

start()