# -*- coding: utf8 -*-
 
from itertools import cycle
import random
import sys
 
import pygame #將pygame庫導入到python程序中
from pygame.locals import * #需要引入pygame中的所有常量。
 
 
FPS = 30
SCREENWIDTH = 288 #屏幕寬度
SCREENHEIGHT = 512 #屏幕高度
# amount by which base can maximum shift to left
PIPEGAPSIZE = 100 # gap between upper and lower part of pipe 管道上下之間的間隙
BASEY  = SCREENHEIGHT * 0.79 #base那個條條所在的高度 注意以左上角為坐標起始點 所以這個高度是往下為正
# image, sound and hitmask dicts
IMAGES, SOUNDS, HITMASKS = {}, {}, {} #圖像，聲音，撞擊的文件
 
# list of all possible players (tuple of 3 positions of flap) #三種小鳥造型
PLAYERS_LIST = (
 # red bird
 (
  'assets/sprites/redbird-upflap.png',
  'assets/sprites/redbird-midflap.png',
  'assets/sprites/redbird-downflap.png',
 ),
 # blue bird
 (
  # amount by which base can maximum shift to left
  'assets/sprites/bluebird-upflap.png',
  'assets/sprites/bluebird-midflap.png',
  'assets/sprites/bluebird-downflap.png',
 ),
 # yellow bird
 (
  'assets/sprites/yellowbird-upflap.png',
  'assets/sprites/yellowbird-midflap.png',
  'assets/sprites/yellowbird-downflap.png',
 ),
)
 
# list of backgrounds 兩種背景，一種白天，一種黑夜
BACKGROUNDS_LIST = (
 'assets/sprites/background-day.png',
 'assets/sprites/background-night.png',
)
 
# list of pipes 管道的兩種顏色，一種綠色，一種紅色
PIPES_LIST = (
 'assets/sprites/pipe-green.png',
 'assets/sprites/pipe-red.png',
)
 
 
try:
 xrange
except NameError:
 xrange = range
 
 
def main():
 global SCREEN, FPSCLOCK
 pygame.init() #經過初始化以后我們就可以盡情地使用pygame了。
 
 #使用Pygame時鐘之前，必須先創建Clock對象的一個實例，
 FPSCLOCK = pygame.time.Clock()#控制每個循環多長時間運行一次。這就像一個定時器在控制時間進程，指出“現在開始下一個循環”！現在開始下一個循環！……
 
 SCREEN = pygame.display.set_mode((SCREENWIDTH, SCREENHEIGHT))#通常來說我們需要先創建一個窗口，方便我們與程序的交互。
 pygame.display.set_caption('Flappy Bird')#設置窗口標題
 
 # numbers sprites for score display #加載并轉換圖像
 #在pygame中可以使用pygame.image.load（）函數來加載位圖 （支持jpg,png,gif,bmp,pcx,tif,tga等多種圖片格式）。
 #convert_alpha()方法會使用透明的方法繪制前景對象。
 # 因此在加載一個有alpha通道的素材時（比如PNG TGA），需要使用convert_alpha()方法，當然普通的圖片也是可以使用這個方法的，用了也不會有什么副作用。
 IMAGES['numbers'] = (
  pygame.image.load('assets/sprites/0.png').convert_alpha(),
  pygame.image.load('assets/sprites/1.png').convert_alpha(),
  pygame.image.load('assets/sprites/2.png').convert_alpha(),
  pygame.image.load('assets/sprites/3.png').convert_alpha(),
  pygame.image.load('assets/sprites/4.png').convert_alpha(),
  pygame.image.load('assets/sprites/5.png').convert_alpha(),
  pygame.image.load('assets/sprites/6.png').convert_alpha(),
  pygame.image.load('assets/sprites/7.png').convert_alpha(),
  pygame.image.load('assets/sprites/8.png').convert_alpha(),
  pygame.image.load('assets/sprites/9.png').convert_alpha()
 )
 
 # game over sprite 游戲結束顯示的圖像
 IMAGES['gameover'] = pygame.image.load('assets/sprites/gameover.png').convert_alpha()
 # message sprite for welcome screen 歡迎界面顯示的圖像
 IMAGES['message'] = pygame.image.load('assets/sprites/message.png').convert_alpha()
 # base (ground) sprite 始終顯示的base圖像
 IMAGES['base'] = pygame.image.load('assets/sprites/base.png').convert_alpha()
 
 # sounds
 # WAV版 OGG版是指游戲的音頻格式
 # WAV版是屬于游戲原版
 # OGG是大大們通過轉換器把音頻格式的WAV改成OGG，這樣游戲的配置提高要求使游戲本身的體積而縮小節省了空間。
 #可以看一下同一個音頻 ogg版的是比wav版的文件小很多
 if 'win' in sys.platform: #判斷當前系統平臺 來設置聲音文件后綴
  soundExt = '.wav'
 else:
  soundExt = '.ogg'
 
 # 音效:pygame.mixer
 # sound = pygame.mixer.Sound('/home/liumin/love.wav')使用指定文件名載入一個音頻文件，并創建一個Sound對象。 音頻文件可以是wav,ogg等格式。
 # 音頻文件的內容會被全部載入到內存中。
 SOUNDS['die'] = pygame.mixer.Sound('assets/audio/die' + soundExt)
 SOUNDS['hit'] = pygame.mixer.Sound('assets/audio/hit' + soundExt)
 SOUNDS['point'] = pygame.mixer.Sound('assets/audio/point' + soundExt)
 SOUNDS['swoosh'] = pygame.mixer.Sound('assets/audio/swoosh' + soundExt)
 SOUNDS['wing'] = pygame.mixer.Sound('assets/audio/wing' + soundExt)
 
 while True:
  # select random background sprites 加載隨機背景 （白天或者黑夜）
  randBg = random.randint(0, len(BACKGROUNDS_LIST) - 1)#隨機選擇0或者1
  IMAGES['background'] = pygame.image.load(BACKGROUNDS_LIST[randBg]).convert()#加載隨機背景
 
  # select random player sprites 加載隨機角色 （紅色、藍色、黃色小鳥）
  randPlayer = random.randint(0, len(PLAYERS_LIST) - 1)
  IMAGES['player'] = (
   pygame.image.load(PLAYERS_LIST[randPlayer][0]).convert_alpha(),
   pygame.image.load(PLAYERS_LIST[randPlayer][1]).convert_alpha(),
   pygame.image.load(PLAYERS_LIST[randPlayer][2]).convert_alpha(),
  )
 
  # select random pipe sprites 加載隨機管道樣式
  pipeindex = random.randint(0, len(PIPES_LIST) - 1)
  IMAGES['pipe'] = (
   pygame.transform.rotate(
    pygame.image.load(PIPES_LIST[pipeindex]).convert_alpha(), 180),#旋轉180度
   pygame.image.load(PIPES_LIST[pipeindex]).convert_alpha(),
  )#一個上面的管道 一個下面的管道
 
  # hismask for pipes #得到管道的邊界mask
  HITMASKS['pipe'] = (
   getHitmask(IMAGES['pipe'][0]),
   getHitmask(IMAGES['pipe'][1]),
  )
 
  # hitmask for player #得到player的邊界mask
  HITMASKS['player'] = (
   getHitmask(IMAGES['player'][0]),
   getHitmask(IMAGES['player'][1]),
   getHitmask(IMAGES['player'][2]),
  )
 
  movementInfo = showWelcomeAnimation()#返回'playery'（player所在位置）,'basex'（base圖像所在位置） 'playerIndexGen'（飛行姿勢index）
  crashInfo = mainGame(movementInfo)
  showGameOverScreen(crashInfo)
 
 
def showWelcomeAnimation():
 """Shows welcome screen animation of flappy bird"""
 # index of player to blit on screen
 playerIndex = 0
 playerIndexGen = cycle([0, 1, 2, 1])
 # iterator used to change playerIndex after every 5th iteration
 loopIter = 0
 
 #player所在位置
 playerx = int(SCREENWIDTH * 0.2)
 playery = int((SCREENHEIGHT - IMAGES['player'][0].get_height()) / 2)
 #歡迎圖像所在位置
 messagex = int((SCREENWIDTH - IMAGES['message'].get_width()) / 2)
 messagey = int(SCREENHEIGHT * 0.12)
 
 basex = 0
 # amount by which base can maximum shift to left 可以最大限度地向左移動的距離
 baseShift = IMAGES['base'].get_width() - IMAGES['background'].get_width()
 
 # player shm for up-down motion on welcome screen 角色在歡迎屏幕上進行上下移動
 playerShmVals = {'val': 0, 'dir': 1}
 
 while True:
  for event in pygame.event.get():#使用pygame.event.get()來處理所有的事件,
   if event.type == QUIT or (event.type == KEYDOWN and event.key == K_ESCAPE):#如果 quit 或者 按鍵之后又按下esc，就結束游戲
    pygame.quit()
    sys.exit()
   if event.type == KEYDOWN and (event.key == K_SPACE or event.key == K_UP):#如果按鍵之后點擊或者按下↑
    # make first flap sound and return values for mainGame
    SOUNDS['wing'].play()#播放飛的特效聲音
    return {#返回初始位置 進入maingame
     'playery': playery + playerShmVals['val'],
     'basex': basex,
     'playerIndexGen': playerIndexGen,
    }
 
  # adjust playery, playerIndex, basex
  if (loopIter + 1) % 5 == 0:
   playerIndex = next(playerIndexGen)#獲得匹配元素集合中每個元素緊鄰的同胞元素 調整飛行姿勢圖片
  loopIter = (loopIter + 1) % 30
  basex = -((-basex + 4) % baseShift)
  playerShm(playerShmVals)
 
  # draw sprites
  #screen.blit(space, (0,0))可以繪制位圖 第一個參數是加載完成的位圖，第二個參數是繪制的起始坐標。
  SCREEN.blit(IMAGES['background'], (0,0))
  SCREEN.blit(IMAGES['player'][playerIndex],
     (playerx, playery + playerShmVals['val']))
  SCREEN.blit(IMAGES['message'], (messagex, messagey))
  SCREEN.blit(IMAGES['base'], (basex, BASEY))
 
  pygame.display.update()#更新整個窗口
  FPSCLOCK.tick(FPS)#循環應該多長時間運行一次
 
 
def mainGame(movementInfo):
 score = playerIndex = loopIter = 0#初始得分以及初始player的姿態以及迭代次數都為0
 playerIndexGen = movementInfo['playerIndexGen']#得到飛行姿勢
 playerx, playery = int(SCREENWIDTH * 0.2), movementInfo['playery']#player所在位置
 
 basex = movementInfo['basex']#base圖像所在位置
 baseShift = IMAGES['base'].get_width() - IMAGES['background'].get_width()
 
 # get 2 new pipes to add to upperPipes lowerPipes list
 newPipe1 = getRandomPipe()
 newPipe2 = getRandomPipe()
 
 # list of upper pipes
 upperPipes = [
  {'x': SCREENWIDTH + 200, 'y': newPipe1[0]['y']},
  {'x': SCREENWIDTH + 200 + (SCREENWIDTH / 2), 'y': newPipe2[0]['y']},
 ]
 
 # list of lowerpipe
 lowerPipes = [
  {'x': SCREENWIDTH + 200, 'y': newPipe1[1]['y']},
  {'x': SCREENWIDTH + 200 + (SCREENWIDTH / 2), 'y': newPipe2[1]['y']},
 ]
 
 pipeVelX = -4
 
 # player velocity, max velocity, downward accleration, accleration on flap 角色速度，最大速度，向下加速度，襟翼加速度
 playerVelY = -9 # player's velocity along Y, default same as playerFlapped
 playerMaxVelY = 10 # max vel along Y, max descend speed
 playerMinVelY = -8 # min vel along Y, max ascend speed
 playerAccY = 1 # players downward accleration
 playerRot  = 45 # player's rotation
 playerVelRot = 3 # angular speed
 playerRotThr = 20 # rotation threshold
 playerFlapAcc = -9 # players speed on flapping
 playerFlapped = False # True when player flaps
 
 
 while True:
  for event in pygame.event.get():
   if event.type == QUIT or (event.type == KEYDOWN and event.key == K_ESCAPE):
    pygame.quit()
    sys.exit()
   if event.type == KEYDOWN and (event.key == K_SPACE or event.key == K_UP):
    if playery > -2 * IMAGES['player'][0].get_height():#如果點擊
     playerVelY = playerFlapAcc#上升
     playerFlapped = True
     SOUNDS['wing'].play()#并播放飛行音效
 
  # check for crash here
  crashTest = checkCrash({'x': playerx, 'y': playery, 'index': playerIndex},
        upperPipes, lowerPipes)
  if crashTest[0]:#如果掉在地上或者撞擊到了管道，就返回結束游戲
   return {
    'y': playery,
    'groundCrash': crashTest[1],
    'basex': basex,
    'upperPipes': upperPipes,
    'lowerPipes': lowerPipes,
    'score': score,
    'playerVelY': playerVelY,
    'playerRot': playerRot
   }
 
  # check for score
  playerMidPos = playerx + IMAGES['player'][0].get_width() / 2
  for pipe in upperPipes:
   pipeMidPos = pipe['x'] + IMAGES['pipe'][0].get_width() / 2
   if pipeMidPos <= playerMidPos < pipeMidPos + 4:#當角色達到管道縫隙的中間+4時，score+1，并且在此時播放得分音效
    score += 1
    SOUNDS['point'].play()
 
  # playerIndex basex change
  if (loopIter + 1) % 3 == 0:
   playerIndex = next(playerIndexGen)
  loopIter = (loopIter + 1) % 30
  basex = -((-basex + 100) % baseShift)
 
  # rotate the player
  if playerRot > -90:
   playerRot -= playerVelRot
 
  # player's movement
  if playerVelY < playerMaxVelY and not playerFlapped:
   playerVelY += playerAccY
  if playerFlapped:
   playerFlapped = False
 
   # more rotation to cover the threshold (calculated in visible rotation)
   playerRot = 45
 
  playerHeight = IMAGES['player'][playerIndex].get_height()
  playery += min(playerVelY, BASEY - playery - playerHeight)
 
  # move pipes to left
  for uPipe, lPipe in zip(upperPipes, lowerPipes):
   uPipe['x'] += pipeVelX #管道移動
   lPipe['x'] += pipeVelX
 
  # add new pipe when first pipe is about to touch left of screen
  if 0 < upperPipes[0]['x'] < 5:#當第一個管道移動到屏幕左側邊緣時，生成下一個管道
   newPipe = getRandomPipe()
   upperPipes.append(newPipe[0])
   lowerPipes.append(newPipe[1])
 
  # remove first pipe if its out of the screen
  if upperPipes[0]['x'] < -IMAGES['pipe'][0].get_width(): #當管道移動到屏幕外側后，刪除它
   upperPipes.pop(0)
   lowerPipes.pop(0)
 
  # draw sprites
  SCREEN.blit(IMAGES['background'], (0,0))
 
  for uPipe, lPipe in zip(upperPipes, lowerPipes):
   SCREEN.blit(IMAGES['pipe'][0], (uPipe['x'], uPipe['y']))
   SCREEN.blit(IMAGES['pipe'][1], (lPipe['x'], lPipe['y']))
 
  SCREEN.blit(IMAGES['base'], (basex, BASEY))
  # print score so player overlaps the score
  showScore(score) #顯示得分
 
  # Player rotation has a threshold
  visibleRot = playerRotThr
  if playerRot <= playerRotThr:
   visibleRot = playerRot
  
  playerSurface = pygame.transform.rotate(IMAGES['player'][playerIndex], visibleRot)#旋轉角色
  SCREEN.blit(playerSurface, (playerx, playery))#顯示旋轉后的角色
 
  pygame.display.update()#更新窗口
  FPSCLOCK.tick(FPS)#循環應該多長時間運行一次
 
 
def showGameOverScreen(crashInfo):
 """crashes the player down ans shows gameover image"""
 score = crashInfo['score']#獲取得分
 playerx = SCREENWIDTH * 0.2
 playery = crashInfo['y']
 playerHeight = IMAGES['player'][0].get_height()
 playerVelY = crashInfo['playerVelY']
 playerAccY = 2
 playerRot = crashInfo['playerRot']
 playerVelRot = 7
 
 basex = crashInfo['basex']
 
 upperPipes, lowerPipes = crashInfo['upperPipes'], crashInfo['lowerPipes']
 
 # play hit and die sounds
 SOUNDS['hit'].play()
 if not crashInfo['groundCrash']:#如果沒有撞擊到地面，就播放die音效就可以了
  SOUNDS['die'].play()
 
 while True:
  for event in pygame.event.get():
   if event.type == QUIT or (event.type == KEYDOWN and event.key == K_ESCAPE):
    pygame.quit()
    sys.exit()
   if event.type == KEYDOWN and (event.key == K_SPACE or event.key == K_UP):
    if playery + playerHeight >= BASEY - 1:
     return
 
  # player y shift
  if playery + playerHeight < BASEY - 1:
   playery += min(playerVelY, BASEY - playery - playerHeight)
 
  # player velocity change
  if playerVelY < 15:
   playerVelY += playerAccY
 
  # rotate only when it's a pipe crash
  if not crashInfo['groundCrash']:
   if playerRot > -90:
    playerRot -= playerVelRot
 
  # draw sprites
  SCREEN.blit(IMAGES['background'], (0,0))
 
  for uPipe, lPipe in zip(upperPipes, lowerPipes):
   SCREEN.blit(IMAGES['pipe'][0], (uPipe['x'], uPipe['y']))
   SCREEN.blit(IMAGES['pipe'][1], (lPipe['x'], lPipe['y']))
 
  SCREEN.blit(IMAGES['base'], (basex, BASEY))
  showScore(score)
 
  playerSurface = pygame.transform.rotate(IMAGES['player'][1], playerRot)
  SCREEN.blit(playerSurface, (playerx,playery))
 
  FPSCLOCK.tick(FPS)
  pygame.display.update()
 
 
def playerShm(playerShm):
 """oscillates the value of playerShm['val'] between 8 and -8"""
 if abs(playerShm['val']) == 8:
  playerShm['dir'] *= -1
 
 if playerShm['dir'] == 1:
   playerShm['val'] += 1
 else:
  playerShm['val'] -= 1
 
 
def getRandomPipe():#隨機生成隨機高度的管道 ？？？？？？？？還需要看細節
 """returns a randomly generated pipe"""
 # y of gap between upper and lower pipe
 gapY = random.randrange(0, int(BASEY * 0.6 - PIPEGAPSIZE))
 gapY += int(BASEY * 0.2)
 pipeHeight = IMAGES['pipe'][0].get_height()
 pipeX = SCREENWIDTH + 10
 
 return [
  {'x': pipeX, 'y': gapY - pipeHeight}, # upper pipe
  {'x': pipeX, 'y': gapY + PIPEGAPSIZE}, # lower pipe
 ]
 
 
def showScore(score):
 """displays score in center of screen"""
 scoreDigits = [int(x) for x in list(str(score))]
 totalWidth = 0 # total width of all numbers to be printed
 
 for digit in scoreDigits:
  totalWidth += IMAGES['numbers'][digit].get_width()
 
 Xoffset = (SCREENWIDTH - totalWidth) / 2
 
 for digit in scoreDigits:
  SCREEN.blit(IMAGES['numbers'][digit], (Xoffset, SCREENHEIGHT * 0.1))#顯示得分
  Xoffset += IMAGES['numbers'][digit].get_width()
 
 
def checkCrash(player, upperPipes, lowerPipes):
 """returns True if player collders with base or pipes."""
 pi = player['index']#飛行姿勢
 player['w'] = IMAGES['player'][0].get_width()
 player['h'] = IMAGES['player'][0].get_height()
 
 # if player crashes into ground 掉在地上
 if player['y'] + player['h'] >= BASEY - 1:
  return [True, True] #返回
 else:
 
  playerRect = pygame.Rect(player['x'], player['y'],
      player['w'], player['h'])
  pipeW = IMAGES['pipe'][0].get_width()
  pipeH = IMAGES['pipe'][0].get_height()
 
  for uPipe, lPipe in zip(upperPipes, lowerPipes):
   # upper and lower pipe rects
   uPipeRect = pygame.Rect(uPipe['x'], uPipe['y'], pipeW, pipeH)
   lPipeRect = pygame.Rect(lPipe['x'], lPipe['y'], pipeW, pipeH)
 
   # player and upper/lower pipe hitmasks
   pHitMask = HITMASKS['player'][pi]
   uHitmask = HITMASKS['pipe'][0]
   lHitmask = HITMASKS['pipe'][1]
 
   # if bird collided with upipe or lpipe
   uCollide = pixelCollision(playerRect, uPipeRect, pHitMask, uHitmask)
   lCollide = pixelCollision(playerRect, lPipeRect, pHitMask, lHitmask)
 
   if uCollide or lCollide:#如果撞擊到了上管道或者下管道 返回
    return [True, False]
 
 return [False, False]
 
def pixelCollision(rect1, rect2, hitmask1, hitmask2):
 """Checks if two objects collide and not just their rects"""
 rect = rect1.clip(rect2)#角色和管道之間重合的情況
 
 if rect.width == 0 or rect.height == 0:#沒重合就是沒撞擊到
  return False
 
 x1, y1 = rect.x - rect1.x, rect.y - rect1.y
 x2, y2 = rect.x - rect2.x, rect.y - rect2.y
 
 for x in xrange(rect.width):
  for y in xrange(rect.height):
   if hitmask1[x1+x][y1+y] and hitmask2[x2+x][y2+y]:#撞擊到了
    return True
 return False
 
def getHitmask(image):
 """returns a hitmask using an image's alpha."""
 #得到撞擊mask
 mask = []
 for x in xrange(image.get_width()):
  mask.append([])
  for y in xrange(image.get_height()):
   mask[x].append(bool(image.get_at((x,y))[3]))
 return mask
 
if __name__ == '__main__':
 main()