''' This module contains generic utility and helper functions.
The comments give a basic idea of each function's purpose.
This module is mostly included in Skellington Plus.'''

import pygame
from pygame.locals import *
import os
import codecs
import datetime

from locals import *

import data

from sound import play_sound

from variables import Variables

from log import error_message, log_message

class Score:
  def __init__(self, score, life = PLAYER_LIFE, time = 0, levels = 0):
    self.score = score
    self.life = life
    self.time = time
    self.levels = levels
    return

class Util:

  pygame.font.init()
  smallfont = pygame.font.Font(data.filepath(os.path.join("/usr/share/fonts/truetype/dejavu", "DejaVuSans.ttf")), FONT_SIZE)
  cached_text_images = {}
  cached_images = {}
  cached_images["key_z"] = pygame.image.load(data.picpath("key", "z"))
  cached_images["key_p"] = pygame.image.load(data.picpath("key", "p"))
  cached_images["health_bar_fill"] = pygame.image.load(data.picpath("health_bar", "fill"))
  cached_images["health_bar_empty"] = pygame.image.load(data.picpath("health_bar", "empty"))
  fade_state = FADE_STATE_BLACK
  blackscreen = pygame.Surface((SCREEN_WIDTH, SCREEN_HEIGHT))

'''This function returns a path for saving config in the user's home directory.
It's compatible with both UNIX-likes (environment variable HOME)
and Windows (environment variable APPDATA).
Prints error messages if unsuccesful, and reverts to a "saves" directory
under the data directory instead.'''
def get_config_path():
  path_name = ""
  try:
    path_name = os.path.join(os.environ["HOME"], "." + GAME_NAME_SHORT)
  except:
    error_message("Couldn't find environment variable HOME, reverting to APPDATA. This is normal under Windows.")
    try:
      path_name = os.path.join(os.environ["APPDATA"], GAME_NAME_SHORT)
    except:
      error_message("Couldn't get environment variable for home directory, using data directory instead.")
      path_name = data.filepath("saves")
  if not os.path.exists(path_name):
    os.mkdir(path_name)
  return path_name

'''This parses a config file stored in the location given by get_config_path().
The parsed values are stored in the Variables class of the variables module.'''
def parse_config():
  for world in WORLDS:
    Variables.vdict["unlocked" + world] = 0
    Variables.vdict["hiscore" + world] = 0
    Variables.vdict["besttime" + world] = 0
  Variables.vdict["sound"] = True
  Variables.vdict["dialogue"] = True
  Variables.vdict["verbose"] = False
  Variables.vdict["fullscreen"] = False
  file_path = os.path.join(get_config_path(), "config.txt")
  try:
    conffile = codecs.open(file_path, "r", "utf_8")
    for line in conffile:
      if line.strip() != "":
        values = line.split("\t")

        if values[0] == "unlocked":
          try:
            Variables.vdict["unlocked" + values[1]] = int(values[2])
          except:
            Variables.vdict["unlocked" + WORLDS[0]] = int(values[1])  #Old style config file compatibility

        elif values[0] == "hiscore":
          try:
            Variables.vdict["hiscore" + values[1]] = int(values[2])
          except:
            Variables.vdict["hiscore" + WORLDS[0]] = int(values[1])  #Old style config file compatibility

        elif values[0] == "besttime":
          Variables.vdict["besttime" + values[1]] = int(values[2])

        elif values[0] == "sound":
          Variables.vdict["sound"] = str_to_bool(values[1])

        elif values[0] == "dialogue":
          Variables.vdict["dialogue"] = str_to_bool(values[1])

        elif values[0] == "fullscreen":
          Variables.vdict["fullscreen"] = str_to_bool(values[1])

  except:
    if write_config():
      log_message("Created configuration file to " + file_path)
  return

'''Writes the config stored in the Variables class to the configuration file.
Prints an error message if unsuccesful.'''
def write_config():
  file_path = os.path.join(get_config_path(), "config.txt")
  try:
    conffile = codecs.open(file_path, "w", "utf_8")
    for world in WORLDS:
      print >> conffile, "unlocked\t%(world)s\t%(unlocked)s" % {"world": world, "unlocked": Variables.vdict["unlocked" + world]}
      print >> conffile, "hiscore\t%(world)s\t%(hiscore)s" % {"world": world, "hiscore": Variables.vdict["hiscore" + world]}
      print >> conffile, "besttime\t%(world)s\t%(besttime)s" % {"world": world, "besttime": Variables.vdict["besttime" + world]}
    print >> conffile, "sound\t%s" % bool_to_str(Variables.vdict["sound"])
    print >> conffile, "dialogue\t%s" % bool_to_str(Variables.vdict["dialogue"])
    print >> conffile, "fullscreen\t%s" % bool_to_str(Variables.vdict["fullscreen"])
  except:
    error_message("Could not write configuration file to " + file_path)
    return False
  return True
  
#Writes the message log to disk.
def write_log():
  file_path = os.path.join(get_config_path(), "log.txt")
  old_log = ""
  if os.path.exists(file_path):
    conffile = open(file_path)
    count = 0
    for line in conffile:
      old_log = old_log + line
      count += 1
      if count > MAX_OLD_LOG_LINES:
        break
  if Variables.vdict.has_key("log"):
    try:
      conffile = codecs.open(file_path, "w", "utf_8")
      print >> conffile, "Log updated " + str(datetime.date.today())
      print >> conffile, Variables.vdict["log"]
      print >> conffile, ""
      print >> conffile, old_log
    except:
      error_message("Could not write log file to " + file_path)
      return False
  return True

def str_to_bool(string):
  string = string.strip()
  return (string == "true" or string == "True" or string == "1" or string == "on")

def bool_to_str(bool):
  if bool:
    return "on"
  else:
    return "off"

''' This function renders fancy-looking text and handles caching of text images
Returns a pygame surface containing the rendered text
The text is rendered with slight edges to make it look more readable on a
colorful background.

The constant colors can be found from locals.py.
'''
def render_text(string, color = COLOR_GUI, bgcolor = COLOR_GUI_BG):
  if Util.cached_text_images.has_key(string + str(color) + str(bgcolor)):
    final_image = Util.cached_text_images[string + str(color) + str(bgcolor)]
  else:
    text_image_bg = Util.smallfont.render(string, True, bgcolor)
    text_image_fg = Util.smallfont.render(string, True, color)
    rect = text_image_bg.get_rect()
    final_image = pygame.Surface((rect.width + 2, rect.height + 2)).convert_alpha()

    final_image.fill((0,0,0,0))

    final_image.blit(text_image_bg, rect)
    final_image.blit(text_image_bg, (1,0))
    final_image.blit(text_image_bg, (2,0))

    final_image.blit(text_image_bg, (0,2))
    final_image.blit(text_image_bg, (1,2))
    final_image.blit(text_image_bg, (2,2))

    final_image.blit(text_image_fg, (1,1))
    Util.cached_text_images[string + str(color) + str(bgcolor)] = final_image
  return final_image

'''This function renders text partially.
For fancy dialogue display.
The phase value is the amount of characters shown.
-1 phase means that the whole string is visible.
'''
def render_text_dialogue(screen, string, phase, key = "z"):
  if phase == -1:
    phase = len(string)

  rendered_string = string[0:phase]
  string_image = render_text(rendered_string)
  string_rect = string_image.get_rect()
  string_rect.centerx = SCREEN_WIDTH / 2
  string_rect.centery = SCREEN_HEIGHT / 2

  if key == "p":
    skip_image = Util.cached_images["key_p"]
  else:
    skip_image = Util.cached_images["key_z"]

  skip_rect = skip_image.get_rect()
  skip_rect.centerx = SCREEN_WIDTH / 2
  skip_rect.top = string_rect.bottom + 5

  bg_rect = pygame.Rect(string_rect.left - 10, string_rect.top - 5, string_rect.width + 20, string_rect.height + skip_rect.height + 15)
  bg_image = pygame.Surface((bg_rect.width, bg_rect.height))  
  bg_image.set_alpha(FADE_STATE_HALF)

  screen.blit(bg_image, bg_rect)

  screen.blit(string_image, string_rect)

  screen.blit(skip_image, skip_rect)

  if phase < len(string):
    phase += 1
    play_sound("click")
  else:
    return -1

  return phase

def cycle_clockwise(orientation):
  orientation += 1
  if orientation > 3:
    orientation = 0
  return orientation

def cycle_counter_clockwise(orientation):
  orientation -= 1
  if orientation < 0:
    orientation = 3
  return orientation

def get_direction(orientation):
  if orientation == RIGHT:
    return (1, 0)
  if orientation == LEFT:
    return (-1, 0)
  if orientation == UP:
    return (0, -1)
  if orientation == DOWN:
    return (0, 1)
  return (0, 0)

def dir_from_str(string):
  if string == "LEFT":
    return LEFT
  if string == "UP":
    return UP
  if string == "DOWN":
    return DOWN
  return RIGHT
  
def str_from_dir(direction):
  if direction == LEFT:
    return "LEFT"
  if direction == UP:
    return "UP"    
  if direction == DOWN:
    return "DOWN"
  return "RIGHT"

'''This function fades the screen to black.
Both fade-in and fade-out.
Returns true if the fading has finished.
fade_target should be an integer (0-255)
* 255 = FADE_STATE_BLACK : The display is all black
* 0 = FADE_STATE_NONE : The display is not faded at all'''
def fade_to_black(screen, fade_target):
  if Util.fade_state > fade_target:
    Util.fade_state += int(255 / (FPS * FADE_IN))
    if Util.fade_state < fade_target:
      Util.fade_state = fade_target
  if Util.fade_state < fade_target:
    Util.fade_state -= -int(255 / (FPS * FADE_OUT))
    if Util.fade_state > fade_target:
      Util.fade_state = fade_target
  if Util.fade_state > FADE_STATE_NONE:
    Util.blackscreen.set_alpha(Util.fade_state)
    screen.blit(Util.blackscreen, screen.get_rect())
  return (Util.fade_state == fade_target)

'''Applies the fullscreen setting stored in variables to the screen.
screen is a pygame standard surface.
Contents of the screen should not be affected.'''
def apply_fullscreen_setting(screen):
  mode = 0
  if Variables.vdict["fullscreen"]:
    mode ^= FULLSCREEN
  tmp = pygame.Surface((SCREEN_WIDTH,SCREEN_HEIGHT)).convert()
  tmp.blit(screen,(0,0))
  screen = pygame.display.set_mode((SCREEN_WIDTH,SCREEN_HEIGHT),mode)
  screen.blit(tmp,(0,0))
  pygame.display.flip()