"""Hello, and welcome to the source code of Gorillas.py. This program is meant to be very well documented so that a
novice programmer can follow along. This program was written by Al Sweigart as a companion for his free, Creative
Commons-licensed book "Invent Your Own Computer Games with Python", which is available in full at:

       http://inventwithpython.com

Feel free to email the author with any programming questions at [email protected]

This program seeks to replicate gorillas.bas, a Qbasic program that was popular in the 1990s. By reading
through the comments, you can learn how a simple Python game with the Pygame engine is put together.

The comments will generally come _after_ the lines of code they describe.

If you like this, then check out inventwithpython.com to read the book (which has similar game projects) for free!

The Pygame documentation is pretty good, and can be found at http://www.pygame.org/docs

Unfortunately there is no sound with this game.
"""

import pygame, sys, time, random, math
from pygame.locals import *
"""We'll import quite a few modules for this game. "pygame" has all the graphics & game-related functions that the
Pygame game engine provides. "sys" has the exit() function. "time" has the sleep() function. "random" has the randint()
function, and "math" contains the pi constant."""


"""All of the variables below in CAPS LETTERS are constants, that is, they are only supposed to be read and not
modified. (There's nothing to keep the program from modifying them, but it's just a convention programmers use.
The constants are a bit more descriptive than just using the numbers by themselves. And if you ever want to change
some value (such as the size of the explosions or the color of the gorillas), you only have to change it in one
place."""

SCR_WIDTH = 640
SCR_HEIGHT = 350
FPS = 30
GAME_CLOCK = pygame.time.Clock()
"""Here are several constants we will use in the game. The original Qbasic game had a screen size of 640x350, so we'll
use that as our screen size. We will use a single global Clock object to handle some of the timing stuff in all our
functions, and generally have FPS set to 30 (except when we want to set it to something else.

Constants are useful because you can just change the value in one place, and it will be used throughout the program.

Try experimenting with different values for these global constants."""

BUILDING_COLORS = ((173, 170, 173), (0, 170, 173), (173, 0, 0))
LIGHT_WINDOW = (255, 255, 82)
DARK_WINDOW = (82, 85, 82)
SKY_COLOR = (0, 0, 173)
GOR_COLOR = (255, 170, 82)
BAN_COLOR = (255, 255, 82)
EXPLOSION_COLOR = (255, 0, 0)
SUN_COLOR = (255, 255, 0)
DARK_RED_COLOR = (173, 0, 0)
BLACK_COLOR = (0, 0, 0)
WHITE_COLOR = (255, 255, 255)
GRAY_COLOR = (173, 170, 173)
"""Here are a bunch of colors. Pygame uses a tuple of three integers to specify a color. The integers are for the
amount of Red, Blue, and Green (in order) in the color. This is known as an RGB value.

BUILDING_COLORS will hold a tuple of these RGB tuples and represent the different colors the buildings can be."""

BUILD_EXPLOSION_SIZE = int(SCR_HEIGHT / 50)
GOR_EXPLOSION_SIZE = 30
"""BUILD_EXPLOSION_SIZE holds the size of an explosion when a banana hits a building, and GOR_EXPLOSION_SIZE is the size
when it hits a gorilla."""

SUN_X = 300
SUN_Y = 10
"""The position of the sun in the sky."""

pygame.init()
GAME_FONT = pygame.font.SysFont(None, 20)
"""The pygame.init() function needs to be called before calling any of the Pygame functions.
We will use the default system font at a size of 20 points."""

# orientation of the banana:
RIGHT = 0
UP = 1
LEFT = 2
DOWN = 3
"""Some constants for the direction the banana (or anything else) faces."""

# gorilla arms drawing types
BOTH_ARMS_DOWN = 0
LEFT_ARM_UP = 1
RIGHT_ARM_UP = 2
"""Some constants for which of the three gorilla sprites to use: both arms down, left arm up, or right arm up."""


"""The following multiline strings are used with the makeSurfaceFromASCII() function. It's basically a way of
generating Surfaces other than using the drawing functions or including graphic files along with this .py file.

Try experimenting by changing the strings. The first and last line are ignored (so you don't have to deal with
indentation issues in the string)."""

STAR_ASCII = """


  XX  XX
   XXXX
 XXXXXXXX
   XXXX
  XX  XX
"""

GOR_DOWN_ASCII = """

         XXXXXXXX
         XXXXXXXX
        XX      XX
        XXXXXXXXXX
        XXX  X  XX
         XXXXXXXX
         XXXXXXXX
          XXXXXX
     XXXXXXXXXXXXXXXX
  XXXXXXXXXXXXXXXXXXXXXX
 XXXXXXXXXXXX XXXXXXXXXXX
XXXXXXXXXXXXX XXXXXXXXXXXX
XXXXXXXXXXXX X XXXXXXXXXXX
XXXXX XXXXXX XXX XXXXX XXXXX
XXXXX XXX   XXXXX   XX XXXXX
XXXXX   XXXXXXXXXXXX   XXXXX
XXXXX  XXXXXXXXXXXX  XXXXX
XXXXX  XXXXXXXXXXXX  XXXXX
 XXXXX XXXXXXXXXXXX XXXXX
  XXXXXXXXXXXXXXXXXXXXXX
      XXXXXXXXXXXXX
    XXXXXX     XXXXXX
    XXXXX       XXXXX
   XXXXX         XXXXX
   XXXXX         XXXXX
   XXXXX         XXXXX
   XXXXX         XXXXX
   XXXXX         XXXXX
    XXXXX       XXXXX
"""

GOR_LEFT_ASCII = """
  XXXXX
 XXXXX   XXXXXXXX
XXXXX    XXXXXXXX
XXXXX   XX      XX
XXXXX    XXXXXXXXXX
XXXXX    XXX  X  XX
XXXXX     XXXXXXXX
XXXXX    XXXXXXXX
XXXXX     XXXXXX
 XXXXXXXXXXXXXXXXXXXX
  XXXXXXXXXXXXXXXXXXXXXX
     XXXXXXXX XXXXXXXXXXX
     XXXXXXXX XXXXXXXXXXXX
     XXXXXXX X XXXXXXXXXXX
     XXXXXX XXX XXXXX XXXXX
     XXX   XXXXX   XX XXXXX
       XXXXXXXXXXXX   XXXXX
       XXXXXXXXXXXX  XXXXX
       XXXXXXXXXXXX  XXXXX
       XXXXXXXXXXXX XXXXX
      XXXXXXXXXXXXXXXXXX
      XXXXXXXXXXXXX
    XXXXXX     XXXXXX
    XXXXX       XXXXX
   XXXXX         XXXXX
   XXXXX         XXXXX
   XXXXX         XXXXX
   XXXXX         XXXXX
   XXXXX         XXXXX
    XXXXX       XXXXX
"""

GOR_RIGHT_ASCII = """
                   XXXXX
         XXXXXXXX   XXXXX
         XXXXXXXX    XXXXX
        XX      XX   XXXXX
        XXXXXXXXXX    XXXXX
        XXX  X  XX    XXXXX
         XXXXXXXX     XXXXX
         XXXXXXXX    XXXXX
          XXXXXX     XXXXX
     XXXXXXXXXXXXXXXXXXXX
  XXXXXXXXXXXXXXXXXXXXXX
 XXXXXXXXXXXX XXXXXXX
XXXXXXXXXXXXX XXXXXXX
XXXXXXXXXXXX X XXXXXX
XXXXX XXXXXX XXX XXXXX
XXXXX XXX   XXXXX   XX
XXXXX   XXXXXXXXXXXX
XXXXX  XXXXXXXXXXXX
XXXXX  XXXXXXXXXXXX
 XXXXX XXXXXXXXXXXX
  XXXXXXXXXXXXXXXXX
      XXXXXXXXXXXXX
    XXXXXX     XXXXXX
    XXXXX       XXXXX
   XXXXX         XXXXX
   XXXXX         XXXXX
   XXXXX         XXXXX
   XXXXX         XXXXX
   XXXXX         XXXXX
    XXXXX       XXXXX
"""

BAN_RIGHT_ASCII = """
    XX
   XXX
  XXX
  XXX
  XXX
  XXX
  XXX
   XXX
    XX
"""

BAN_LEFT_ASCII = """
XX
XXX
XXX
XXX
XXX
XXX
XXX
XXX
XX
"""

BAN_UP_ASCII = """
XX     XX
XXXXXXXXX
XXXXXXX
 XXXXX
"""

BAN_DOWN_ASCII = """
 XXXXX
XXXXXXX
XXXXXXXXX
XX     XX
"""

SUN_NORMAL_ASCII = """
                   X
                   X
           X       X       X
            X      X      X
            X      X      X
    X        X     X     X        X
     X        X XXXXXXX X        X
      XX      XXXXXXXXXXX      XX
        X  XXXXXXXXXXXXXXXXX  X
         XXXXXXXXXXXXXXXXXXXXX
 X       XXXXXXXXXXXXXXXXXXXXX       X
  XXXX  XXXXXXXXXXXXXXXXXXXXXXX  XXXX
      XXXXXXXXXX XXXXX XXXXXXXXXX
       XXXXXXXX   XXX   XXXXXXXX
       XXXXXXXXX XXXXX XXXXXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
       XXXXXXXXXXXXXXXXXXXXXXXXX
       XXXXXXXXXXXXXXXXXXXXXXXXX
      XXXXXX XXXXXXXXXXXXX XXXXXX
  XXXX  XXXXX  XXXXXXXXX  XXXXX  XXXX
 X       XXXXXX  XXXXX  XXXXXX       X
         XXXXXXXX     XXXXXXXX
        X  XXXXXXXXXXXXXXXXX  X
      XX      XXXXXXXXXXX      XX
     X        X XXXXXXX X        X
    X        X     X     X        X
            X      X      X
            X      X      X
           X       X       X
                   X
                   X
"""

SUN_SHOCKED_ASCII = """
                   X
                   X
           X       X       X
            X      X      X
            X      X      X
    X        X     X     X        X
     X        X XXXXXXX X        X
      XX      XXXXXXXXXXX      XX
        X  XXXXXXXXXXXXXXXXX  X
         XXXXXXXXXXXXXXXXXXXXX
 X       XXXXXXXXXXXXXXXXXXXXX       X
  XXXX  XXXXXXXXXXXXXXXXXXXXXXX  XXXX
      XXXXXXXXXX XXXXX XXXXXXXXXX
       XXXXXXXX   XXX   XXXXXXXX
       XXXXXXXXX XXXXX XXXXXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
       XXXXXXXXXXXXXXXXXXXXXXXXX
       XXXXXXXXXXXXXXXXXXXXXXXXX
      XXXXXXXXXXXXXXXXXXXXXXXXXXX
  XXXX  XXXXXXXXX     XXXXXXXXX  XXXX
 X       XXXXXXX       XXXXXXX       X
         XXXXXXX       XXXXXXX
        X  XXXXXX     XXXXXX  X
      XX      XXXXXXXXXXX      XX
     X        X XXXXXXX X        X
    X        X     X     X        X
            X      X      X
            X      X      X
           X       X       X
                   X
                   X
"""

def terminate():
   """Calls both the pygame.quit() and sys.exit() functions, to end the program. (I found that not calling
   pygame.quit() before sys.exit() can mess up IDLE sometimes."""
   pygame.quit()
   sys.exit()

def makeSurfaceFromASCII(ascii, fgColor=(255,255,255), bgColor=(0,0,0)):
   """Returns a new pygame.Surface object that has the image drawn on it as specified by the ascii parameter.
   The first and last line in ascii are ignored. Otherwise, any X in ascii marks a pixel with the foreground color
   and any other letter marks a pixel of the background color. The Surface object has a width of the widest line
   in the ascii string, and is always rectangular."""

   """Try experimenting with this function so that you can specify more than two colors. (Pass a dict of
   ascii letters and RGB tuples, say."""
   ascii = ascii.split('\n')[1:-1]
   width = max([len(x) for x in ascii])
   height = len(ascii)
   surf = pygame.Surface((width, height))
   surf.fill(bgColor)

   pArr = pygame.PixelArray(surf)
   for y in range(height):
       for x in range(len(ascii[y])):
           if ascii[y][x] == 'X':
               pArr[x][y] = fgColor
   return surf

GOR_DOWN_SURF    = makeSurfaceFromASCII(GOR_DOWN_ASCII,    GOR_COLOR,      SKY_COLOR)
GOR_LEFT_SURF    = makeSurfaceFromASCII(GOR_LEFT_ASCII,    GOR_COLOR,      SKY_COLOR)
GOR_RIGHT_SURF   = makeSurfaceFromASCII(GOR_RIGHT_ASCII,   GOR_COLOR,      SKY_COLOR)
BAN_RIGHT_SURF   = makeSurfaceFromASCII(BAN_RIGHT_ASCII,   BAN_COLOR,      SKY_COLOR)
BAN_LEFT_SURF    = makeSurfaceFromASCII(BAN_LEFT_ASCII,    BAN_COLOR,      SKY_COLOR)
BAN_UP_SURF      = makeSurfaceFromASCII(BAN_UP_ASCII,      BAN_COLOR,      SKY_COLOR)
BAN_DOWN_SURF    = makeSurfaceFromASCII(BAN_DOWN_ASCII,    BAN_COLOR,      SKY_COLOR)
SUN_NORMAL_SURF  = makeSurfaceFromASCII(SUN_NORMAL_ASCII,  SUN_COLOR,      SKY_COLOR)
SUN_SHOCKED_SURF = makeSurfaceFromASCII(SUN_SHOCKED_ASCII, SUN_COLOR,      SKY_COLOR)
STAR_SURF        = makeSurfaceFromASCII(STAR_ASCII,        DARK_RED_COLOR, BLACK_COLOR)

assert GOR_DOWN_SURF.get_size() == GOR_LEFT_SURF.get_size() == GOR_RIGHT_SURF.get_size()
"""Create the pygame.Surface objects from the ASCII strings."""

sunRect = pygame.Rect(SUN_X, SUN_Y, SUN_NORMAL_SURF.get_width(), SUN_NORMAL_SURF.get_height())
"""sunRect will be a global value so we'll always know where the sun is."""

def drawText(text, surfObj, x, y, fgcol, bgcol, pos='left'):
   """A generic function to draw a string to a pygame.Surface object at a certain x,y location. This returns
   a pygame.Rect object which describes the area the string was drawn on.

   If the pos parameter is "left", then the x,y parameter specifies the top left corner of the text rectangle.
   If the pos parameter is "center", then the x,y parameter specifies the middle top point of the text rectangle."""

   textobj = GAME_FONT.render(text, 1, fgcol, bgcol) # creates the text in memory (it's not on a surface yet).
   textrect = textobj.get_rect()

   if pos == 'left':
       textrect.topleft = (x, y)
   elif pos == 'center':
       textrect.midtop = (x, y)
   surfObj.blit(textobj, textrect) # draws the text onto the surface
   """Remember that the text will only appear on the screen if you pass the pygame.Surface object that was
   returned from the call to pygame.display.set_mode(), and only after pygame.display.update() is called."""
   return textrect

def getModCase(s, mod):
   """Checks the state of the shift and caps lock keys, and switches the case of the s string if needed."""
   if bool(mod & KMOD_RSHIFT or mod & KMOD_LSHIFT) ^ bool(mod & KMOD_CAPS):
       return s.swapcase()
   else:
       return s

def inputMode(prompt, screenSurf, x, y, fgcol, bgcol, maxlen=12, allowed=None, pos='left', cursor='_', cursorBlink=False):
   """Takes control of the program when called. This function displays a prompt on the screen (the "prompt" string)
   parameter) on the screenSurf surface at the x, y coordinates. The text is in the fgcol color with a bgcol color
   background. You can optionally specify maxlen for a maximum length of the user's response. "allowed" is a string
   of allowed characters (if the player can only type numbers, say) and ignores all other keystrokes. The "pos"
   parameter can either be the string "left" (where the x, y coordinates refer to the top left corner of the text
   box) or "center" (where the x, y coordinates refer to the top center of the text box).

   "cursor" is an optional character that is used for a cursor to show where the next letter will go. If "cursorBlink"
   is True, then this cursor character will blink on and off.

   The returned value is a string of what the player typed in, or None if the player pressed the Esc key.

   Note that the player can only press Backspace to delete characters, they cannot use the arrow keys to move the
   cursor."""
   inputText = ''
   """inputText will store the text of what the player has typed in so far."""
   done = False
   cursorTimestamp = time.time()
   cursorShow = cursor
   while not done:
       """We will keep looping until the player has pressed the Esc or Enter key."""

       if cursor and cursorBlink and time.time() - 1.0 > cursorTimestamp:
           if cursorShow == cursor:
               cursorShow = '   '
           else:
               cursorShow = cursor
           cursorTimestamp = time.time()

       for event in pygame.event.get():
           if event.type == QUIT:
               terminate()
           elif event.type == KEYUP:
               if event.key == K_ESCAPE:
                   return None
               elif event.key == K_RETURN:
                   done = True
                   if cursorShow:
                       cursorShow = '   '
               elif event.key == K_BACKSPACE:
                   if len(inputText):
                       drawText(prompt + inputText + cursorShow, screenSurf, textrect.left, textrect.top, bgcol, bgcol, 'left')
                       inputText = inputText[:-1]
               else:
                   if len(inputText) >= maxlen or (allowed is not None and chr(event.key) not in allowed):
                       continue
                   if event.key >= 32 and event.key < 128:
                       inputText += getModCase(chr(event.key), event.mod)

       textrect = drawText(prompt + cursorShow, screenSurf, x, y, fgcol, bgcol, pos)
       drawText(prompt + inputText + cursorShow, screenSurf, textrect.left, textrect.top, fgcol, bgcol, 'left')
       pygame.display.update()
       GAME_CLOCK.tick(FPS)
   return inputText

def nextBananaShape(orient):
   """Returns the next banana shape in the sequence of 0, 1, 2, 3, then 0 again. (These correspond to the RIGHT, UP,
   LEFT, and DOWN variables."""
   if orient + 1 == 4:
       return 0
   else:
       return orient + 1

def drawBanana(screenSurf, orient, x, y):
   """Draws the banana shape to the screenSurf surface with its top left corner at the x y coordinate provided.
   "orient" is one of the RIGHT, UP, LEFT, or DOWN values (which are the integers 0 to 3 respectively)"""
   if orient == DOWN:
       screenSurf.blit(BAN_DOWN_SURF, (x, y))
   elif orient == UP:
       screenSurf.blit(BAN_UP_SURF, (x, y))
   elif orient == LEFT:
       screenSurf.blit(BAN_LEFT_SURF, (x, y))
   elif orient == RIGHT:
       screenSurf.blit(BAN_RIGHT_SURF, (x, y))


def drawSun(screenSurf, shocked=False):
   """Draws the sun sprite onto the screenSurf surface. If shocked is True, then use the shocked-looking face,
   otherwise use the normal smiley face. This function does not call python.display.update()"""
   if shocked:
       screenSurf.blit(SUN_SHOCKED_SURF, (SUN_X, SUN_Y))
   else:
       screenSurf.blit(SUN_NORMAL_SURF, (SUN_X, SUN_Y))


def drawGorilla(screenSurf, x, y, arms=BOTH_ARMS_DOWN):
   """Draws the gorilla sprite onto the screenSurf surface at a specific x, y coordinate. The x,y coordinate
   is for the top left corner of the gorilla sprite. Note that all three gorilla surfaces are the same size."""

   if arms == BOTH_ARMS_DOWN:
       gorSurf = GOR_DOWN_SURF
   elif arms == LEFT_ARM_UP:
       gorSurf = GOR_LEFT_SURF
   elif arms == RIGHT_ARM_UP:
       gorSurf = GOR_RIGHT_SURF
   """Above we choose which surface object we will use to draw the gorilla, depending on the "arms" parameter.
   The call to screenSurf.blit() will draw the surface onto the screen (but it won't show up on the screen until
   pygame.display.update() is called."""

   screenSurf.blit(gorSurf, (x, y))

def makeCityScape():
   """This function creates and returns a new cityscape of various buildings on a pygame.Surface object and returns
   this surface object."""

   screenSurf = pygame.Surface((SCR_WIDTH, SCR_HEIGHT)) # first make the new surface the same size of the screen.
   screenSurf.fill(SKY_COLOR) # fill in the surface with the background sky color

   """We will choose an upward, downward, valley "v" curve, or hilly "^" curve for the slope of the buildings.
   Half of the time we will choose the valley slope shape, while the remaining three each have a 1/6 chance of
   being choosen. The slope also determines the height of the first building, which is stored in newHeight."""
   slope = random.randint(1, 6)
   if slope == 1:
       slope = 'upward'
       newHeight = 15
   elif slope == 2:
       slope = 'downward'
       newHeight = 130
   elif slope >= 3 and slope <= 5:
       slope = 'v'
       newHeight = 15
   else:
       slope = '^'
       newHeight = 130

   bottomLine = 335 # the bottom line of the buildings. We want some space for the wind arrow to go
   heightInc = 10 # a baseline for how much buildings grow or shrink compared to the last building
   defBuildWidth = 37 # default building width, also judges how wide buildings can be
   randomHeightDiff = 120 # about how much buildings grow or shrink
   windowWidth = 4 # the width of each window in pixels
   windowHeight = 7 # the height of each window in pixels
   windowSpacingX = 10 # how many pixels apart each window's left edge is
   windowSpacingY = 15 # how many pixels apart each window's top edge is
   gHeight = 25 # (I'm not sure what this suppoes to be in the original Qbasic code, but I copied it anyway)
   # (There also was a maxHeight variable in the original Qbasic, but I don't think it did anything so I left it out.)

   buildingCoords = [] # a list of (left, top) coords of each building, left to right

   x = 2 # x refers to the top left corner of the current building being drawn

   while x < SCR_WIDTH - heightInc:
       # In this loop we keep drawing new buildings until we run out of space on the screen.

       # First the slope type determines if the building should grow or shrink.
       if slope == 'upward':
           newHeight += heightInc
       elif slope == 'downward':
           newHeight -= heightInc
       elif slope == 'v':
           if x > SCR_WIDTH / 2:
               newHeight -= (2 * heightInc)
               # For valley slopes, buildings shrink on the left half of the screen...
           else:
               newHeight += (2 * heightInc)
               # ...and grow on the right half.
       else:
           if x > SCR_WIDTH / 2:
               newHeight += (2 * heightInc)
               # For hilley slopes, buildings grow on the left half of the screen...
           else:
               newHeight -= (2 * heightInc)
               # ...and shrink on the right half.

       # Get the new building's width.
       buildWidth = defBuildWidth + random.randint(0, defBuildWidth)
       if buildWidth + x > SCR_WIDTH:
           buildWidth = SCR_WIDTH - x -2

       # Get the new building's height
       buildHeight = random.randint(heightInc, randomHeightDiff) + newHeight

       # Check if the height is too high.
       if bottomLine - buildHeight <= gHeight:
           buildHeight = gHeight

       # Randomly select one of the building colors.
       buildingColor = BUILDING_COLORS[random.randint(0, len(BUILDING_COLORS)-1)]

       # Draw the building
       pygame.draw.rect(screenSurf, buildingColor, (x+1, bottomLine - (buildHeight+1), buildWidth-1, buildHeight-1))

       buildingCoords.append( (x, bottomLine - buildHeight) )

       # Draw the windows
       for winx in range(3, buildWidth - windowSpacingX + windowWidth, windowSpacingX):
           for winy in range(3, buildHeight - windowSpacingY, windowSpacingY):
               if random.randint(1, 4) == 1:
                   winColor = DARK_WINDOW
               else:
                   winColor = LIGHT_WINDOW
               pygame.draw.rect(screenSurf, winColor, (x + 1 + winx, (bottomLine - buildHeight) + 1 + winy, windowWidth, windowHeight))

       x += buildWidth

   # We want to return both the surface object we've drawn the buildings on, and the coordinates of each building.
   return screenSurf, buildingCoords

def placeGorillas(buildCoords):
   """Using the buildingCoords value returned from makeCityScape(), we want to place the gorillas on the left and right
   side of the screen on the second or third building from the edge."""

   gorPos = [] # item 0 is for (left, top) of player one, item 1 is for player two.
   xAdj = int(GOR_DOWN_SURF.get_rect().width / 2)
   yAdj = GOR_DOWN_SURF.get_rect().height

   for i in range(0,2): # place first and then second player

       # place gorillas on second or third building from the edge.
       if i == 0:
           buildNum = random.randint(1,2)
       else:
           buildNum = random.randint(len(buildCoords)-3, len(buildCoords)-2)

       buildWidth = buildCoords[buildNum + 1][0] - buildCoords[buildNum][0]
       gorPos.append( (buildCoords[buildNum][0] + int(buildWidth / 2) - xAdj, buildCoords[buildNum][1] - yAdj - 1) )

   # The format of the gorPos list is [(p1 x, p1 y), (p2 x, p2 y)]
   return gorPos

def waitForPlayerToPressKey():
   """Calling this function will pause the program until the user presses a key. The key is returned."""
   while True:
       key = checkForKeyPress()
       if key:
           return key

def checkForKeyPress():
   """Calling this function will check if a key has recently been pressed. If so, the key is returned.
   If not, then False is returned. If the Esc key was pressed, then the program terminates."""
   for event in pygame.event.get():
       if event.type == QUIT:
           terminate()
       if event.type == KEYUP:
           if event.key == K_ESCAPE: # pressing escape quits
               terminate()
           return event.key
   return False

def showStartScreen(screenSurf):
   """Draws the starting introductory screen to screenSurf, with red stars rotating around the border. This screen
   remains until the user presses a key."""
   vertAdj = 0
   horAdj = 0
   while not checkForKeyPress():
       screenSurf.fill(BLACK_COLOR)

       drawStars(screenSurf, vertAdj, horAdj)
       vertAdj += 1
       if vertAdj == 4: vertAdj = 0
       horAdj += 12
       if horAdj == 84: horAdj = 0
       """The stars on the sides of the screen move 1 pixel each iteration through this loop and reset every 4
       pixels. The stars on the top and bottom of the screen move 12 pixels each iteration and reset every 84 pixels."""

       drawText('P  y  t  h  o  n     G  O  R  I  L  L  A  S', screenSurf, SCR_WIDTH / 2, 50, WHITE_COLOR, BLACK_COLOR, pos='center')
       drawText('Your mission is to hit your opponent with the exploding', screenSurf, SCR_WIDTH / 2, 110, GRAY_COLOR, BLACK_COLOR, pos='center')
       drawText('banana by varying the angle and power of your throw, taking', screenSurf, SCR_WIDTH / 2, 130, GRAY_COLOR, BLACK_COLOR, pos='center')
       drawText('into account wind speed, gravity, and the city skyline.', screenSurf, SCR_WIDTH / 2, 150, GRAY_COLOR, BLACK_COLOR, pos='center')
       drawText('The wind speed is shown by a directional arrow at the bottom', screenSurf, SCR_WIDTH / 2, 170, GRAY_COLOR, BLACK_COLOR, pos='center')
       drawText('of the playing field, its length relative to its strength.', screenSurf, SCR_WIDTH / 2, 190, GRAY_COLOR, BLACK_COLOR, pos='center')
       drawText('Press any key to continue', screenSurf, SCR_WIDTH / 2, 300, GRAY_COLOR, BLACK_COLOR, pos='center')

       pygame.display.update()
       GAME_CLOCK.tick(FPS)

def showGameOverScreen(screenSurf, p1name, p1score, p2name, p2score):
   """Draws the game over screen to screenSurf, showing the players' names and scores. This screen has rotating
   red stars too, and hangs around until the user presses a key."""
   p1score = str(p1score)
   p2score = str(p2score)
   vertAdj = 0
   horAdj = 0
   while not checkForKeyPress():
       screenSurf.fill(BLACK_COLOR)

       drawStars(screenSurf, vertAdj, horAdj)
       vertAdj += 1
       if vertAdj == 4: vertAdj = 0
       horAdj += 12
       if horAdj == 84: horAdj = 0
       """The stars on the sides of the screen move 1 pixel each iteration through this loop and reset every 4
       pixels. The stars on the top and bottom of the screen move 12 pixels each iteration and reset every 84 pixels."""

       drawText('GAME OVER!', screenSurf, SCR_WIDTH / 2, 120, GRAY_COLOR, BLACK_COLOR, pos='center')
       drawText('Score:', screenSurf, SCR_WIDTH / 2, 155, GRAY_COLOR, BLACK_COLOR, pos='center')
       drawText(p1name, screenSurf, 225, 170, GRAY_COLOR, BLACK_COLOR)
       drawText(p1score, screenSurf, 395, 170, GRAY_COLOR, BLACK_COLOR)
       drawText(p2name, screenSurf, 225, 185, GRAY_COLOR, BLACK_COLOR)
       drawText(p2score, screenSurf, 395, 185, GRAY_COLOR, BLACK_COLOR)
       drawText('Press any key to continue', screenSurf, SCR_WIDTH / 2, 298, GRAY_COLOR, BLACK_COLOR, pos='center')

       pygame.display.update()
       GAME_CLOCK.tick(FPS)

def drawStars(screenSurf, vertAdj, horAdj):
   """This function draws the red stars on the border of screenSurf."""
   for i in range(16):
       # draw top row of stars
       screenSurf.blit(STAR_SURF, (2 + (((3 - vertAdj) + i * 4) * STAR_SURF.get_width()), 3))
       # draw bottom row of stars
       screenSurf.blit(STAR_SURF, (2 + ((vertAdj + i * 4) * STAR_SURF.get_width()), SCR_HEIGHT - 7 - STAR_SURF.get_height()))

   for i in range(4):
       # draw left column of stars going down
       screenSurf.blit(STAR_SURF, (5, 6 + STAR_SURF.get_height() + (horAdj + i * 84)))
       # draw right column of stars going up
       screenSurf.blit(STAR_SURF, (SCR_WIDTH - 5 - STAR_SURF.get_width(), (SCR_HEIGHT - (6 + STAR_SURF.get_height() + (horAdj + i * 84)))))



def showSettingsScreen(screenSurf):
   """This is the screen that lets the user type in their name and settings for the game."""
   p1name = None
   p2name = None
   points = None
   gravity = None

   screenSurf.fill(BLACK_COLOR)

   while p1name is None:
       p1name = inputMode("Name of Player 1 (Default = 'Player 1'):  ", screenSurf, SCR_WIDTH / 2 - 146, 50, GRAY_COLOR, BLACK_COLOR, maxlen=10, pos='left', cursorBlink=True)
   if p1name == '':
       p1name = 'Player 1'

   while p2name is None:
       p2name = inputMode("Name of Player 2 (Default = 'Player 2'):  ", screenSurf, SCR_WIDTH / 2 - 146, 80, GRAY_COLOR, BLACK_COLOR, maxlen=10, pos='left', cursorBlink=True)
   if p2name == '':
       p2name = 'Player 2'

   while points is None:
       points = inputMode("Play to how many total points (Default = 3)?  ", screenSurf, SCR_WIDTH / 2 - 155, 110, GRAY_COLOR, BLACK_COLOR, maxlen=6, allowed='0123456789', pos='left', cursorBlink=True)
   if points == '':
       points = 3
   else:
       points = int(points)

   while gravity is None:
       gravity = inputMode("Gravity in Meters/Sec (Earth = 9.8)?  ", screenSurf, SCR_WIDTH / 2 - 150, 140, GRAY_COLOR, BLACK_COLOR, maxlen=6, allowed='0123456789.', pos='left', cursorBlink=True)
   if gravity == '':
       gravity = 9.8
   else:
       gravity = float(gravity)

   drawText('--------------', screenSurf, SCR_WIDTH / 2 -10, 170, GRAY_COLOR, BLACK_COLOR, pos='center')
   drawText('V = View Intro', screenSurf, SCR_WIDTH / 2 -10, 200, GRAY_COLOR, BLACK_COLOR, pos='center')
   drawText('P = Play Game', screenSurf, SCR_WIDTH / 2 -10, 230, GRAY_COLOR, BLACK_COLOR, pos='center')
   drawText('Your Choice?', screenSurf, SCR_WIDTH / 2 -10, 260, GRAY_COLOR, BLACK_COLOR, pos='center')
   pygame.display.update()

   key = waitForPlayerToPressKey()
   while chr(key) != 'v' and chr(key) != 'p':
       key = waitForPlayerToPressKey()

   return p1name, p2name, points, gravity, chr(key) # returns 'v' or 'p'

def showIntroScreen(screenSurf, p1name, p2name):
   """This is the screen that plays if the user selected "view intro" from the starting screen."""
   screenSurf.fill(SKY_COLOR)
   drawText('P  y  t  h  o  n     G  O  R  I  L  L  A  S', screenSurf, SCR_WIDTH / 2, 15, WHITE_COLOR, SKY_COLOR, pos='center')
   drawText('STARRING:', screenSurf, SCR_WIDTH / 2, 55, WHITE_COLOR, SKY_COLOR, pos='center')
   drawText('%s AND %s' % (p1name, p2name), screenSurf, SCR_WIDTH / 2, 115, WHITE_COLOR, SKY_COLOR, pos='center')

   x = 278
   y = 175

   for i in range(2):
       drawGorilla(screenSurf, x-13, y, RIGHT_ARM_UP)
       drawGorilla(screenSurf, x+47, y, LEFT_ARM_UP)
       pygame.display.update()

       time.sleep(2)

       drawGorilla(screenSurf, x-13, y, LEFT_ARM_UP)
       drawGorilla(screenSurf, x+47, y, RIGHT_ARM_UP)
       pygame.display.update()

       time.sleep(2)

   for i in range(4):
       drawGorilla(screenSurf, x-13, y, LEFT_ARM_UP)
       drawGorilla(screenSurf, x+47, y, RIGHT_ARM_UP)
       pygame.display.update()

       time.sleep(0.3)

       drawGorilla(screenSurf, x-13, y, RIGHT_ARM_UP)
       drawGorilla(screenSurf, x+47, y, LEFT_ARM_UP)
       pygame.display.update()

       time.sleep(0.3)


def getShot(screenSurf, p1name, p2name, playerNum):
   """getShot() is called when we want to get the angle and velocity from the player."""
   pygame.draw.rect(screenSurf, SKY_COLOR, (0, 0, 200, 50))
   pygame.draw.rect(screenSurf, SKY_COLOR, (550, 0, 00, 50))

   drawText(p1name, screenSurf, 2, 2, WHITE_COLOR, SKY_COLOR)
   drawText(p2name, screenSurf, 538, 2, WHITE_COLOR, SKY_COLOR)

   if playerNum == 1:
       x = 2
   else:
       x = 538

   angle = ''
   while angle == '':
       angle = inputMode('Angle:  ', screenSurf, x, 18, WHITE_COLOR, SKY_COLOR, maxlen=3, allowed='0123456789')
   if angle is None: terminate()
   angle = int(angle)

   velocity = ''
   while velocity == '':
       velocity = inputMode('Velocity:  ', screenSurf, x, 34, WHITE_COLOR, SKY_COLOR, maxlen=3, allowed='0123456789')
   if velocity is None: terminate()
   velocity = int(velocity)

   # Erase the user's input
   drawText('Angle:   ' + str(angle), screenSurf, x, 2, SKY_COLOR, SKY_COLOR)
   drawText('Velocity:   ' + str(angle), screenSurf, x, 2, SKY_COLOR, SKY_COLOR)
   pygame.display.update()

   if playerNum == 2:
       angle = 180 - angle

   return (angle, velocity)

def displayScore(screenSurf, oneScore, twoScore):
   """Draws the score on the screenSurf surface."""
   drawText(str(oneScore) + '>Score<' + str(twoScore), screenSurf, 270, 310, WHITE_COLOR, SKY_COLOR, pos='left')

def plotShot(screenSurf, skylineSurf, angle, velocity, playerNum, wind, gravity, gor1, gor2):
   # startx and starty is the upper left corner of the gorilla.
   angle = angle / 180.0 * math.pi
   initXVel = math.cos(angle) * velocity
   initYVel = math.sin(angle) * velocity
   gorWidth, gorHeight = GOR_DOWN_SURF.get_size()
   gor1rect = pygame.Rect(gor1[0], gor1[1], gorWidth, gorHeight)
   gor2rect = pygame.Rect(gor2[0], gor2[1], gorWidth, gorHeight)


   if playerNum == 1:
       gorImg = LEFT_ARM_UP
   else:
       gorImg = RIGHT_ARM_UP
   """The player 1 gorilla on the left uses his left arm to throw, the player 2 gorilla on the right uses his
   right arm to throw."""

   if playerNum == 1:
       startx = gor1[0]
       starty = gor1[1]
   elif playerNum == 2:
       startx = gor2[0]
       starty = gor2[1]

   drawGorilla(screenSurf, startx, starty, gorImg)
   pygame.display.update()
   time.sleep(0.3)
   drawGorilla(screenSurf, startx, starty, BOTH_ARMS_DOWN)
   pygame.display.update()
   """Draw the gorilla throwing the banana."""

   bananaShape = UP

   if playerNum == 2:
       startx += GOR_DOWN_SURF.get_size()[0]

   starty -= getBananaRect(0, 0, bananaShape).height + BAN_UP_SURF.get_size()[1]

   impact = False
   bananaInPlay = True

   t = 1.0
   sunHit = False

   while not impact and bananaInPlay:
       x = startx + (initXVel * t) + (0.5 * (wind / 5) * t**2)
       y = starty + ((-1 * (initYVel * t)) + (0.5 * gravity * t**2))
       """This is basically the equation that describes the banana's arc."""

       if x >= SCR_WIDTH - 10 or x <= 3 or y >= SCR_HEIGHT:
           bananaInPlay = False

       bananaRect = getBananaRect(x, y, bananaShape)
       if bananaShape == UP:
           bananaSurf = BAN_UP_SURF
           bananaRect.left -= 2
           bananaRect.top += 2
       elif bananaShape == DOWN:
           bananaSurf = BAN_DOWN_SURF
           bananaRect.left -= 2
           bananaRect.top += 2
       elif bananaShape == LEFT:
           bananaSurf = BAN_LEFT_SURF
       elif bananaShape == RIGHT:
           bananaSurf = BAN_RIGHT_SURF

       bananaShape = nextBananaShape(bananaShape)

       srcPixArray = pygame.PixelArray(skylineSurf)
       if bananaInPlay and y > 0:

           if sunRect.collidepoint(x, y):
               # banana has hit the sun, so draw the "shocked" face.
               sunHit = True

           # draw the appropriate sun face
           drawSun(screenSurf, shocked=sunHit)

           if bananaRect.colliderect(gor1rect):
               # banana has hit player 1

               """Note that we draw the explosion on the screen (on screenSurf) and on the separate skyline surface (on skylineSurf).
               This is done so that bananas won't hit the sun or any text and accidentally think they've hit something. We also want
               the skylineSurf surface object to keep track of what chunks of the buildings are left."""
               doExplosion(screenSurf, skylineSurf, bananaRect.centerx, bananaRect.centery, explosionSize=int(GOR_EXPLOSION_SIZE*2/3), speed=0.005)
               doExplosion(screenSurf, skylineSurf, bananaRect.centerx, bananaRect.centery, explosionSize=GOR_EXPLOSION_SIZE, speed=0.005)
               drawSun(screenSurf)
               return 'gorilla1'
           elif bananaRect.colliderect(gor2rect):
               # banana has hit player 2
               doExplosion(screenSurf, skylineSurf, bananaRect.centerx, bananaRect.centery, explosionSize=int(GOR_EXPLOSION_SIZE*2/3), speed=0.005)
               doExplosion(screenSurf, skylineSurf, bananaRect.centerx, bananaRect.centery, explosionSize=GOR_EXPLOSION_SIZE, speed=0.005)
               screenSurf.fill(SKY_COLOR, bananaRect) # erase banana
               drawSun(screenSurf)
               return 'gorilla2'
           elif collideWithNonColor(srcPixArray, screenSurf, bananaRect, SKY_COLOR):
               # banana has hit a building
               doExplosion(screenSurf, skylineSurf, bananaRect.centerx, bananaRect.centery)
               screenSurf.fill(SKY_COLOR, bananaRect) # erase banana
               drawSun(screenSurf)
               return 'building'

       del srcPixArray
       """Pygame doesn't let us blit a surface while there is a pixel array of it existing, so we delete it."""

       screenSurf.blit(bananaSurf, (bananaRect.topleft))
       pygame.display.update()
       time.sleep(0.02)

       screenSurf.fill(SKY_COLOR, bananaRect) # erase banana

       t += 0.1 # go forward in the plot.
   drawSun(screenSurf)
   return 'miss'

def victoryDance(screenSurf, x, y):
   """Given the x,y coordinates of the topleft corner of the gorilla sprite, this goes through
   the victory dance routine of the gorilla where they start waving their arms in the air."""
   for i in range(4):
       screenSurf.blit(GOR_LEFT_SURF, (x, y))
       pygame.display.update()
       time.sleep(0.3)
       screenSurf.blit(GOR_RIGHT_SURF, (x, y))
       pygame.display.update()
       time.sleep(0.3)


def collideWithNonColor(pixArr, surfObj, rect, color):
   """This checks the area (described by "rect") on pixArr (a pixel array derived from the surfObj surface object)
   if it has any pixels that are not the color specified by the "color" parameter. This function is used to detect
   if the banana has hit any non-sky colored parts (which means a gorilla or a building)."""
   rightSide = min(rect.right, SCR_WIDTH)
   bottomSide = min(rect.bottom, SCR_HEIGHT)

   for x in range(rect.left, rightSide):
       for y in range(rect.top, bottomSide):
           if surfObj.unmap_rgb(pixArr[x][y]) != color:
               return True
   return False


def getBananaRect(x, y, shape):
   if shape == UP:
       return pygame.Rect((x, y), BAN_UP_SURF.get_size())
   if shape == DOWN:
       return pygame.Rect((x, y), BAN_DOWN_SURF.get_size())
   if shape == LEFT:
       return pygame.Rect((x, y), BAN_LEFT_SURF.get_size())
   if shape == RIGHT:
       return pygame.Rect((x, y), BAN_RIGHT_SURF.get_size())

def getWind():
   """Randomly determine what the wind speed and direction should be for this game."""
   wind = random.randint(5, 15)
   if random.randint(0, 1):
       wind *= -1
   return wind

def drawWind(screenSurf, wind):
   """Draws the wind arrow on the screenSurf object at the bottom of the screen. The "wind" parameter comes from
   a call to getWind()."""
   if wind != 0:
       wind *= 3
       pygame.draw.line(screenSurf, EXPLOSION_COLOR, (int(SCR_WIDTH / 2), SCR_HEIGHT - 5), (int(SCR_WIDTH / 2) + wind, SCR_HEIGHT - 5))
       # draw the arrow end
       if wind > 0: arrowDir = -2
       else:        arrowDir = 2
       pygame.draw.line(screenSurf, EXPLOSION_COLOR, (int(SCR_WIDTH / 2) + wind, SCR_HEIGHT - 5), (int(SCR_WIDTH / 2) + wind + arrowDir, SCR_HEIGHT - 5 - 2))
       pygame.draw.line(screenSurf, EXPLOSION_COLOR, (int(SCR_WIDTH / 2) + wind, SCR_HEIGHT - 5), (int(SCR_WIDTH / 2) + wind + arrowDir, SCR_HEIGHT - 5 + 2))

def doExplosion(screenSurf, skylineSurf, x, y, explosionSize=BUILD_EXPLOSION_SIZE, speed=0.05):
   for r in range(1, explosionSize):
       pygame.draw.circle(screenSurf, EXPLOSION_COLOR, (x, y), r)
       pygame.draw.circle(skylineSurf, EXPLOSION_COLOR, (x, y), r)
       pygame.display.update()
       time.sleep(speed)
   for r in range(explosionSize, 1, -1):
       pygame.draw.circle(screenSurf, SKY_COLOR, (x, y), explosionSize)
       pygame.draw.circle(skylineSurf, SKY_COLOR, (x, y), explosionSize)
       pygame.draw.circle(screenSurf, EXPLOSION_COLOR, (x, y), r)
       pygame.draw.circle(skylineSurf, EXPLOSION_COLOR, (x, y), r)
       pygame.display.update()
       time.sleep(speed)
   pygame.draw.circle(screenSurf, SKY_COLOR, (x, y), 2)
   pygame.draw.circle(skylineSurf, SKY_COLOR, (x, y), 2)
   pygame.display.update()


def main():
   winSurface = pygame.display.set_mode((SCR_WIDTH, SCR_HEIGHT), 0, 32)
   """winSurface, being the surface object returned by pygame.display.set_mode(), will be drawn to the screen
   every time pygame.display.update() is called."""

   # Uncomment either of the following lines to put the game into full screen mode.
   ##winSurface = pygame.display.set_mode((SCR_WIDTH, SCR_HEIGHT), pygame.FULLSCREEN, 32)
   ##pygame.display.toggle_fullscreen()
   pygame.display.set_caption('Gorillas.py')

   showStartScreen(winSurface)

   while True:
       # start a new game
       p1name, p2name, winPoints, gravity, nextScreen = showSettingsScreen(winSurface)
       if nextScreen == 'v':
           showIntroScreen(winSurface, p1name, p2name)

       # Reset the score and make it the first player's turn.
       p1score = 0
       p2score = 0
       turn = 1

       newRound = True
       while p1score < winPoints and p2score < winPoints:
           if newRound:
               # At the start of a new round, make a new city scape, place the gorillas, and get the wind speed.
               skylineSurf, buildCoords = makeCityScape() # Note that the city skyline goes on skylineSurf, not winSurface.
               gorPos = placeGorillas(buildCoords)
               wind = getWind()
               newRound = False

           # Do all the drawing.
           winSurface.blit(skylineSurf, (0,0))
           drawGorilla(winSurface, gorPos[0][0], gorPos[0][1], 0)
           drawGorilla(winSurface, gorPos[1][0], gorPos[1][1], 0)
           drawWind(winSurface, wind)
           drawSun(winSurface)
           displayScore(winSurface, p1score, p2score)

           pygame.display.update()

           angle, velocity = getShot(winSurface, p1name, p2name, turn)
           if turn == 1:
               gorx, gory = gorPos[0][0], gorPos[0][1]
           elif turn == 2:
               gorx, gory = gorPos[1][0], gorPos[1][1]
           result = plotShot(winSurface, skylineSurf, angle, velocity, turn, wind, 9.8, gorPos[0], gorPos[1])

           if result == 'gorilla1':
               victoryDance(winSurface, gorPos[1][0], gorPos[1][1])
               p2score += 1
               newRound = True
           elif result == 'gorilla2':
               victoryDance(winSurface, gorPos[0][0], gorPos[0][1])
               p1score += 1
               newRound = True

           if turn == 1:
               turn = 2
           else:
               turn = 1

       showGameOverScreen(winSurface, p1name, p1score, p2name, p2score)

if __name__ == '__main__':
   main()