;Set up graphics mode
Graphics 800,600

;Seed the random generator (make random numbers actually random)
SeedRnd(MilliSecs())

;Create a back buffer
SetBuffer BackBuffer()
;Set the handle to the center of images
AutoMidHandle True 


Const HUMAN_SPEED = 7 ;The human;s max speed
Const COMPUTER_SPEED = 6 ;The computer;s max speed
Const X_RANDOM_FACTOR = 2 ;The variance of the x speed after colliding with something
Const Y_RANDOM_FACTOR = 1 ;The variance of the y speed after colliding with something
;The ball;s speed at the beginning of a level
Const LEVEL_START_XV_MIN = 3
Const LEVEL_START_XV_MAX = 6
Const LEVEL_START_YV_MIN = -8
Const LEVEL_START_YV_MAX = 8

;TYPES
;The player type: both the human and the opponent
Type Tplayer
   Field y# ;The vertical position of the player
   Field score#
End Type   

;The ball type: for the ball
Type Tball
   Field x#
   Field y#
;xv and yv are the velocity variables
   Field xv#
   Field yv#   
End Type

;IMAGES
;The picture of the human player
Global player1image = LoadImage("player1.bmp")   

;The picture of the computer player
Global player2image = LoadImage("player2.bmp")

;The picture of the ball
Global ballimage = LoadImage("ball.bmp") ;Load the ball image


;TYPE INITIALIZATION

;Create a ball
Global ball.Tball = New Tball
;Create the human
Global player1.Tplayer = New Tplayer
;Create the computer
Global player2.Tplayer = New Tplayer 



;INITIALIZATION
Locate 400,300
Print "Ready...Set";Wait for one second
Flip
Delay(1000)
Locate 420,330
Print "GO!!!"
Flip
;Delay for 1/5 of a second
Delay(200)

;Initialize the level
InitializeLevel()


;Set inital scores
player1\score = 0
player2\score = 0

;MAIN LOOP
While Not KeyHit(1)

;Clear the screen
Cls

;Draw the ball
DrawImage (ballimage,ball\x,ball\y)
;Draw the human
DrawImage (player1image, 60, player1\y)
;Draw the computer
DrawImage (player2image, 740, player2\y)

;Test what user pressed
TestKeyboard()
TestKeyboard2()
;What should AI do?
TestAI()
;Draw the HUD
DrawScore()

Flip

Delay 20

Wend ;END OF MAIN LOOP

;FUNCTIONS
;INITIALIZELEVEL()
;Sets up starting values
Function InitializeLevel()

;Put ball in center of the screen
ball\x = 400
ball\y = 300

;Make the ball move in a random direction
ball\xv = Rand(LEVEL_START_XV_MIN, LEVEL_START_XV_MAX)
ball\yv = Rand(LEVEL_START_YV_MIN, LEVEL_START_YV_MAX)

;Place the players in their correct position
player2\y = 300
player1\y = 300
End Function


;DRAWSCORE()
;Draws the HUD in the top right
Function DrawScore()
;Write the human score
Locate 700, 0
Print "Player 1: " + player1\score
;Write the computer;s score
Locate 700, 30
Print "Player 2: " + player2\score
End Function

;TESTKEYBOARD()
;Moves player up and down based on keyboard
Function TestKeyboard()

;If player presses up, move him up
If KeyDown(200) ; Pfeiltaste hoch
   player1\y = player1\y - HUMAN_SPEED
EndIf

;If player presses down, move him down
If KeyDown(208) ; Pfeiltaste runter
   player1\y = player1\y + HUMAN_SPEED
End If

;if player presses Pause, pause the game
If KeyHit(25) ; P
   ;make screen blank
   Cls
   
   Locate 400,300
   Print "Press 'P' to Unpause Game"   
   Flip
   
   ;wait for player to unpause
   While Not KeyHit(25) ; P
   Wend

EndIf

End Function


Function TestKeyboard2() ; player 2


;If player presses up, move him up
If KeyDown(17) ; W
   player1\y = player2\y - HUMAN_SPEED
EndIf

;If player presses down, move him down
If KeyDown(31) ; S
   player1\y = player2\y + HUMAN_SPEED
EndIf

End Function





;TESTAI()
;Updates ball and score and enemy
Function TestAI()
 

If player1\y <= 0 Then player1\y = 0
   
If player1\y >= 600 Then player1\y = 600   
   
If player2\y <= 0 Then player2\y = 0
   
If player2\y >= 600 Then player2\y = 600         
   
;If ball hits human player, reflect it away from him and vary its velocity and direction
If ImagesCollide(ballimage,ball\x,ball\y,0,player1image,60,player1\y,0)
   ball\xv = -ball\xv + Rand(-X_RANDOM_FACTOR,X_RANDOM_FACTOR)
   ball\yv = ball\yv + Rand(-Y_RANDOM_FACTOR,Y_RANDOM_FACTOR)
   
;If ball hits computer, reflect it away from computer and vary its velocity and direction
ElseIf ImagesCollide(ballimage,ball\x,ball\y,0,player2image,740,player2\y,0)
   ball\xv = -ball\xv + Rand(-X_RANDOM_FACTOR,X_RANDOM_FACTOR)
   ball\yv = ball\yv + Rand(-Y_RANDOM_FACTOR,Y_RANDOM_FACTOR)
   
;If ball hits top wall, reflect it downward
ElseIf ball\y <= 0 
   ball\xv = ball\xv + Rand (-X_RANDOM_FACTOR,X_RANDOM_FACTOR)
   ball\yv = -ball\yv + Rand (-Y_RANDOM_FACTOR,Y_RANDOM_FACTOR) 
   
;If ball hits bottom wall, reflect it upward
ElseIf ball\y >= 600
   ball\xv = ball\xv + Rand (-X_RANDOM_FACTOR,X_RANDOM_FACTOR) 
   ball\yv = -ball\yv + Rand (-Y_RANDOM_FACTOR,Y_RANDOM_FACTOR)
   
;if ball hits left wall, computer has scored so computer gets one more point
ElseIf ball\x <= 0 
   player2\score = player2\score + 1   ;computer scores
   Locate 400,300
   Print "Player 2 Scores!!!"
   Flip
   ;wait two seconds
   Delay(2000)
   
   ;reset level
   InitializeLevel()
   
;If ball hits right wall, human scored so give him a point
ElseIf ball\x >= 800
   player1\score = player1\score + 1   ;human scores
   Locate 400, 300
   Print "Player 1 Scores!!!"
   Flip
   ;wait 2 secs
   Delay(2000)
   ;reset level
   InitializeLevel()
EndIf
   
   ;update ball;s position on screen
   ball\x = ball\x + ball\xv
   ball\y = ball\y + ball\yv
   
End Function