##---------------------------------------------------------------------------##
##
## pyChing -- a Python program to cast and interpret I Ching hexagrams
##
## Copyright (C) 1999,2000 Stephen M. Gava
##
## This program is free software; you can redistribute it and/or modify
## it under the terms of the GNU General Public License as published by
## the Free Software Foundation; either version 2 of the License, or
## (at your option) any later version.
##
## This program is distributed in the hope that it will be of some
## interest to somebody, but WITHOUT ANY WARRANTY; without even the 
## implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
## See the GNU General Public License for more details.
##
## You should have received a copy of the GNU General Public License
## along with this program; see the file COPYING or COPYING.txt. If not, 
##  write to the Free Software Foundation, Inc.,
## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
## The license can also be found at the GNU/FSF website: http://www.gnu.org
##
## Stephen M. Gava
## <elguavas@users.sourceforge.net>
## http://pyching.sourgeforge.net
##
##---------------------------------------------------------------------------##
"""
engine module for pyching 
classes and utility functions
"""
#python library imports
import sys, os, string, whrandom, pickle, time

#
# classes
################

#private classes - should not be directly accessed from outside this module
class Hexagram: 
  """
  single Hexagram data structure template, private class
  
  should only be accessed as an attribute of an instance of the Hexagrams class (below)
  this class is defined at module level to enable pickling of Hexagrams instances
  """
  def __init__(self):
    self.number = ''
    self.name = ''
    self.lineValues = [0,0,0,0,0,0]
    self.infoSource = None

#public classes
class PychingAppDetails:
  """
  holds information about a running instance of the pyching application, public class
  """
  def __init__(self,createConfigDir=1):
    self.title = 'pyChing'
    self.version = '1.0.4'
    self.os = sys.platform
    self.osType = os.name
    self.execPath = os.path.abspath(sys.path[0]) + os.sep
    if os.path.expanduser('~') != '~': #platform supports unix-style home directories
      self.configPath = os.path.join(os.path.expanduser('~'), '.pyching') #user specific config storage
      if createConfigDir:#config dir should be created if it doesn't exist
        if not os.path.exists(self.configPath):
          try:  
            os.mkdir(self.configPath)#make the config dir if it doesn't exist yet
          except IOError:
            sys.stderr.write('warning - unable to create '+self.configPath+'!\n')
      self.savePath = self.configPath #default save path
    else: #platform does not support unix-style home directories
      self.configPath = self.execPath #config for all users is stored in data directory
      self.savePath = os.curdir #default save path is curent working directory
    self.configFile = os.path.join(self.configPath, 'pychingrc')
    self.saveFileExt = '.psv'
    self.internalImageExt = '.#@~'
    self.internalHtmlExt = '.~@#'
    self.saveFileID = ('pyching_save_file',self.version)
    self.emailAddress = 'elguavas@users.sourceforge.net'
    self.webAddress = 'http://pyching.sourceforge.net'

# create an instance of the app details for use throughout this module
#
pyching = PychingAppDetails()
#
#

class Hexagrams:
  """
  holds both Hexagrams for a reading, public class
  """
  def __init__(self, oracleType='coin'):
    """
    initialise self by setting oracle type
    defaults to coin, if specified must be a valid oracle type (coin or yarrow)
    """
    #public data attributes - should read but not written to from outside this module
    #any attributes that need to be modified from outside this module have a 'set_xxx'
    #method available below
    self.question = ''#use SetQuestion (below) to set this attribute from outside this module
    self.oracle = oracleType #oracle being used
    self.hex1 = Hexagram() #Hexagram 1 data structure
    self.hex2 = Hexagram() #Hexagram 2 data structure
    self.currentLine = 0 #current line being cast in Hex1
    self.currentOracleValues = [] #list of oracle values for current line

  def __GetHexDetails(self, hexKey):
    """
    lookup hex name and number, private method
    
    hexKey value should be a list of the non-moving line numbers for the 
    Hexagram being enquired upon (Hex?.Key)
    returns a list of Hexagram details in the form [number, name]
    """
    if hexKey == [7,7,7,7,7,7]: return ('1', "Tch'ien")
    elif hexKey == [8,8,8,8,8,8]: return ('2', "Koun")
    elif hexKey == [7,8,8,8,7,8]: return ('3', "T'oun")
    elif hexKey == [8,7,8,8,8,7]: return ('4', "Mong")
    elif hexKey == [7,7,7,8,7,8]: return ('5', "Hsu")
    elif hexKey == [8,7,8,7,7,7]: return ('6', "Song")
    elif hexKey == [8,7,8,8,8,8]: return ('7', "Cheu")
    elif hexKey == [8,8,8,8,7,8]: return ('8', "Pi")
    elif hexKey == [7,7,7,8,7,7]: return ('9', "Siao Tch'ou")
    elif hexKey == [7,7,8,7,7,7]: return ('10', "Li")
    elif hexKey == [7,7,7,8,8,8]: return ('11', "T'ai")
    elif hexKey == [8,8,8,7,7,7]: return ('12', "P'i")
    elif hexKey == [7,8,7,7,7,7]: return ('13', "Tong Jen")
    elif hexKey == [7,7,7,7,8,7]: return ('14', "Ta You")
    elif hexKey == [8,8,7,8,8,8]: return ('15', "Tchien")
    elif hexKey == [8,8,8,7,8,8]: return ('16', "Yu")
    elif hexKey == [7,8,8,7,7,8]: return ('17', "Souei")
    elif hexKey == [8,7,7,8,8,7]: return ('18', "Kou")
    elif hexKey == [7,7,8,8,8,8]: return ('19', "Lin")
    elif hexKey == [8,8,8,8,7,7]: return ('20', "Kouan")
    elif hexKey == [7,8,8,7,8,7]: return ('21', "Che Ho")
    elif hexKey == [7,8,7,8,8,7]: return ('22', "Pi")
    elif hexKey == [8,8,8,8,8,7]: return ('23', "Po")
    elif hexKey == [7,8,8,8,8,8]: return ('24', "Fou")
    elif hexKey == [7,8,8,7,7,7]: return ('25', "Wou Wang")
    elif hexKey == [7,7,7,8,8,7]: return ('26', "Ta Tch'ou")
    elif hexKey == [7,8,8,8,8,7]: return ('27', "I")
    elif hexKey == [8,7,7,7,7,8]: return ('28', "Ta Kouo")
    elif hexKey == [8,7,8,8,7,8]: return ('29', "K'an")
    elif hexKey == [7,8,7,7,8,7]: return ('30', "Li")
    elif hexKey == [8,8,7,7,7,8]: return ('31', "Hsien")
    elif hexKey == [8,7,7,7,8,8]: return ('32', "Hong")
    elif hexKey == [8,8,7,7,7,7]: return ('33', "Toun")
    elif hexKey == [7,7,7,7,8,8]: return ('34', "Ta Tch'ouang")
    elif hexKey == [8,8,8,7,8,7]: return ('35', "Tchin")
    elif hexKey == [7,8,7,8,8,8]: return ('36', "Ming Yi")
    elif hexKey == [7,8,7,8,7,7]: return ('37', "Tchia Jen")
    elif hexKey == [7,7,8,7,8,7]: return ('38', "K'ouei")
    elif hexKey == [8,8,7,8,7,8]: return ('39', "Tch'ien")
    elif hexKey == [8,7,8,7,8,8]: return ('40', "Tchieh")
    elif hexKey == [7,7,8,8,8,7]: return ('41', "Soun")
    elif hexKey == [7,8,8,8,7,7]: return ('42', "Yi")
    elif hexKey == [7,7,7,7,7,8]: return ('43', "Kouai")
    elif hexKey == [8,7,7,7,7,7]: return ('44', "Keou")
    elif hexKey == [8,8,8,7,7,8]: return ('45', "Ts'ouei")
    elif hexKey == [8,7,7,8,8,8]: return ('46', "Cheng")
    elif hexKey == [8,7,8,7,7,8]: return ('47', "K'oun")
    elif hexKey == [8,7,7,8,7,8]: return ('48', "Tsing")
    elif hexKey == [7,8,7,7,7,8]: return ('49', "Keu")
    elif hexKey == [8,7,7,7,8,7]: return ('50', "Ting")
    elif hexKey == [7,8,8,7,8,8]: return ('51', "Tchen")
    elif hexKey == [8,8,7,8,8,7]: return ('52', "Ken")
    elif hexKey == [8,8,7,8,7,7]: return ('53', "Tchien")
    elif hexKey == [7,7,8,7,8,8]: return ('54', "Kouei Mei")
    elif hexKey == [7,8,7,7,8,8]: return ('55', "Fong")
    elif hexKey == [8,8,7,7,8,7]: return ('56', "Lu")
    elif hexKey == [8,7,7,8,7,7]: return ('57', "Hsuan")
    elif hexKey == [7,7,8,7,7,8]: return ('58', "Touei")
    elif hexKey == [8,7,8,8,7,7]: return ('59', "Houan")
    elif hexKey == [7,7,8,8,7,8]: return ('60', "Tchieh")
    elif hexKey == [7,7,8,8,7,7]: return ('61', "Tchong Fou")
    elif hexKey == [8,8,7,7,8,8]: return ('62', "Siao Kouo")
    elif hexKey == [7,8,7,8,7,8]: return ('63', "Tchi Tchi")
    elif hexKey == [8,7,8,7,8,7]: return ('64', "Wei Tchi")
    else: #raise an exception
      return (0, "lookup error")
      # pass

  def NewLine(self):
    """
    builds next line in Hex1 and completes both Hexagrams after line 6, public method
    """
    if self.currentLine < 6: #build a new Hex1 line
      rc = whrandom.choice #returns a random value from the specified sequence 
      #handle each oracle type
      if self.oracle == 'coin':
        self.currentOracleValues = [rc([2,3]), rc([2,3]), rc([2,3])]
        #for item in self.currentOracleValues: #line value = sum of oracle values 
        # self.hex1.lineValues[self.currentLine] = self.hex1.lineValues[self.currentLine] + item
      self.hex1.lineValues[self.currentLine] = reduce(lambda x,y: x+y, self.currentOracleValues) #line value = sum of oracle values
      #elif self.oracle == 'yarrow':
      # self.oracleValues = [0, 0, 0] #dummy results
      # self.hex1.lineValues[CurrentLine] = 0 #dummy result
      self.currentLine = self.currentLine + 1 #next line is current
    if self.currentLine == 6: #Hex1 is all built
      hex1Key = [0,0,0,0,0,0] #Hex1's details lookup key
      i = 0 #used as a counter in the loop below
      for item in self.hex1.lineValues: #populate Hex1's details lookup key
        if item == 6: hex1Key[i] = 8 #revert to unmoving line number
        elif item == 9: hex1Key[i] = 7 #revert to unmoving line number
        else: hex1Key[i] = item #no change
        i = i + 1 #increment counter    
      [self.hex1.number, self.hex1.name] = self.__GetHexDetails(hex1Key) #lookup Hex1 details
      self.hex1.infoSource = 'pyching_inhtx_data.in'+self.hex1.number+'data()'
      if self.hex1.lineValues != hex1Key: #if there are some moving lines in Hex1
        i = 0 #used as a counter in the loop below
        for item in self.hex1.lineValues: #populate Hex2.lineValues
          if item == 6: self.hex2.lineValues[i] = 7 #move to new line number
          elif item == 9: self.hex2.lineValues[i] = 8 #move to new line number
          else: self.hex2.lineValues[i] = item #no change
          i = i + 1 #increment counter      
        [self.hex2.number, self.hex2.name] = self.__GetHexDetails(self.hex2.lineValues) #lookup Hex2 details
        self.hex2.infoSource = 'pyching_inhtx_data.in'+self.hex2.number+'data()'

  def SetQuestion(self, questionText):
    """
    used to set the Hexagrams.question attribute from outside this module, public method
    """
    self.question = questionText
  
  def __HexStorage(self, file, action):
    """
    store or load a Hexagrams instance to/from disk file using the utility routine
    Storage(), private method

    this private method should be called from the public load and save 
    routines below. action should be 'save' or 'load' .
    """
    if os.path.expanduser('~') != '~': #unix-style home directories
      if not os.path.exists(pyching.savePath): #failsafe if user deleted ~/.pyching while program running :-)
        os.mkdir(pyching.savePath)#make the save dir
    try:
      if action == 'save':
        hexData = (pyching.saveFileID, self.question, self.oracle, self.hex1, 
                self.hex2, self.currentLine, self.currentOracleValues)
        Storage(file, data=hexData)
      elif action == 'load': 
        hexData = Storage(file)
    except IOError: #pass the error back up the line
      raise #re-raise the exception
    else: #no exception, so proceed
      if action == 'load':
        saveFileID, self.question, self.oracle, self.hex1, self.hex2, \
                self.currentLine, self.currentOracleValues = hexData
        return saveFileID #to enable savefile verification and version checking

  def Save(self, file):
    """
    save instance data to disk file, public method

    this function should be called in a 
    try:
    except IOError:
    block, to handle potential disk IO errors
    """
    #fileName = time.strftime('%Y_%m_%d_%H_%M_%S.sav', time.localtime(time.time()))
    try:
      self.__HexStorage(file, 'save')
    except IOError: #pass the error back up the line
      raise #re-raise the exception

  def Load(self, file):
    """
    load instance data from disk file, public method, returns savefile version

    this function should be called in a 
    try:
    except IOError:
    block, to handle potential disk IO errors
    """
    try:
      version = self.__HexStorage(file, 'load')
    except IOError: #pass the error back up the line
      raise #re-raise the exception
    else:
      return version #to enable savefile version check if required
      
  def ReadingAsText(self):
    """
    create a multi-line text representation of the reading as a formatted string, public method,
    returns the string
    """
    #textReading = [] 
    
    lineStrings = {6:'---X---',7:'-------',8:'--- ---',9:'---O---',0:''}#the 0 takes care of an empty Hex2 
    linePositions = {1:'first',2:'second',3:'third',4:'fourth',5:'fifth',6:'topmost'}
    lineTypes = {6:'(6 moving yin)',7:'(7 yang)',8:'(8 yin)',9:'(9 moving yang)',0:''}#the 0 takes care of an empty Hex2 
    
    textReadingParts = []

    textReadingParts.append( '\n              '+string.ljust(self.hex1.number, 2)+\
            ' '+string.ljust(self.hex1.name, 30)+\
            ' '+string.ljust(self.hex2.number, 2)+' '+self.hex2.name+'\n\n' )
    
    for i in range(5,-1,-1):
      if i == 3: 
        if (6 in self.hex1.lineValues) or (9 in self.hex1.lineValues): #if there are moving lines
          separator = '  becomes  '
        else:
          separator = '  no moving lines'
      else:
          separator = '           '
      textReadingParts.append( ' '+string.rjust(linePositions[i +1], 9)+'   '+lineStrings[self.hex1.lineValues[i]]+\
              ' '+string.ljust(lineTypes[self.hex1.lineValues[i]], 15)+separator+\
              lineStrings[self.hex2.lineValues[i]]+' '+lineTypes[self.hex2.lineValues[i]]+'\n'  )
    
    textReadingParts.append('\n '+self.question+'\n\n')

    textReading = string.join(textReadingParts)

    return textReading

#
# utility routines 
######################

def Storage(file, data=None):
  """
  store or load data to/from file using pickler

  data should be a list of data items if storing, or None if loading
  returns an unpickled list of data items on successful load

  this function should be called in a 
  try:
  except IOError:
  except pychingPickleError:
  except pychingUnpickleError:
  block, to handle potential disk IO and pickle/unpickle errors
  """
  if data: openType = 'w'
  else: openType = 'r'
  try:
    pickleFile = open(file, openType)
  except IOError: 
    raise #re-raise the exception to pass it back up the line
  else: #no exception, so proceed
    try:
      try:
        if data: #pickle required data
          pickle.dump(data, pickleFile)
        else: #unpickle data
          pickleData = pickle.load(pickleFile)
          return pickleData
      except:
        if data: raise 'pychingPickleError' #raise an error indicating that the pickle failed
        else: raise 'pychingUnpickleError' #raise an error indicating that the unpickle failed      
    finally: pickleFile.close()