"""Provides access to stored IDLE configuration information.

Refer to the comments at the beginning of config-main.def for a description of

the available configuration files and the design implemented to update user

configuration information.  In particular, user configuration choices which

duplicate the defaults will be removed from the user's configuration files,

and if a file becomes empty, it will be deleted.

The contents of the user files may be altered using the Options/Configure IDLE

menu to access the configuration GUI (configDialog.py), or manually.

Throughout this module there is an emphasis on returning useable defaults

when a problem occurs in returning a requested configuration value back to

idle. This is to allow IDLE to continue to function in spite of errors in

the retrieval of config information. When a default is returned instead of

a requested config value, a message is printed to stderr to aid in

configuration problem notification and resolution.

"""

import os

import sys

import string

import macosxSupport

from ConfigParser import ConfigParser, NoOptionError, NoSectionError

class InvalidConfigType(Exception): pass

class InvalidConfigSet(Exception): pass

class InvalidFgBg(Exception): pass

class InvalidTheme(Exception): pass

class IdleConfParser(ConfigParser):

    """

    A ConfigParser specialised for idle configuration file handling

    """

    def __init__(self, cfgFile, cfgDefaults=None):

        """

        cfgFile - string, fully specified configuration file name

        """

        self.file=cfgFile

        ConfigParser.__init__(self,defaults=cfgDefaults)

    def Get(self, section, option, type=None, default=None):

        """

        Get an option value for given section/option or return default.

        If type is specified, return as type.

        """

        if type=='bool':

            getVal=self.getboolean

        elif type=='int':

            getVal=self.getint

        else:

            getVal=self.get

        if self.has_option(section,option):

            #return getVal(section, option, raw, vars, default)

            return getVal(section, option)

        else:

            return default

    def GetOptionList(self,section):

        """

        Get an option list for given section

        """

        if self.has_section(section):

            return self.options(section)

        else:  #return a default value

            return []

    def Load(self):

        """

        Load the configuration file from disk

        """

        self.read(self.file)

class IdleUserConfParser(IdleConfParser):

    """

    IdleConfigParser specialised for user configuration handling.

    """

    def AddSection(self,section):

        """

        if section doesn't exist, add it

        """

        if not self.has_section(section):

            self.add_section(section)

    def RemoveEmptySections(self):

        """

        remove any sections that have no options

        """

        for section in self.sections():

            if not self.GetOptionList(section):

                self.remove_section(section)

    def IsEmpty(self):

        """

        Remove empty sections and then return 1 if parser has no sections

        left, else return 0.

        """

        self.RemoveEmptySections()

        if self.sections():

            return 0

        else:

            return 1

    def RemoveOption(self,section,option):

        """

        If section/option exists, remove it.

        Returns 1 if option was removed, 0 otherwise.

        """

        if self.has_section(section):

            return self.remove_option(section,option)

    def SetOption(self,section,option,value):

        """

        Sets option to value, adding section if required.

        Returns 1 if option was added or changed, otherwise 0.

        """

        if self.has_option(section,option):

            if self.get(section,option)==value:

                return 0

            else:

                self.set(section,option,value)

                return 1

        else:

            if not self.has_section(section):

                self.add_section(section)

            self.set(section,option,value)

            return 1

    def RemoveFile(self):

        """

        Removes the user config file from disk if it exists.

        """

        if os.path.exists(self.file):

            os.remove(self.file)

    def Save(self):

        """Update user configuration file.

        Remove empty sections. If resulting config isn't empty, write the file

        to disk. If config is empty, remove the file from disk if it exists.

        """

        if not self.IsEmpty():

            fname = self.file

            try:

                cfgFile = open(fname, 'w')

            except IOError:

                os.unlink(fname)

                cfgFile = open(fname, 'w')

            self.write(cfgFile)

        else:

            self.RemoveFile()

class IdleConf:

    """

    holds config parsers for all idle config files:

    default config files

        (idle install dir)/config-main.def

        (idle install dir)/config-extensions.def

        (idle install dir)/config-highlight.def

        (idle install dir)/config-keys.def

    user config  files

        (user home dir)/.idlerc/config-main.cfg

        (user home dir)/.idlerc/config-extensions.cfg

        (user home dir)/.idlerc/config-highlight.cfg

        (user home dir)/.idlerc/config-keys.cfg

    """

    def __init__(self):

        self.defaultCfg={}

        self.userCfg={}

        self.cfg={}

        self.CreateConfigHandlers()

        self.LoadCfgFiles()

        #self.LoadCfg()

    def CreateConfigHandlers(self):

        """

        set up a dictionary of config parsers for default and user

        configurations respectively

        """

        #build idle install path

        if __name__ != '__main__': # we were imported

            idleDir=os.path.dirname(__file__)

        else: # we were exec'ed (for testing only)

            idleDir=os.path.abspath(sys.path[0])

        userDir=self.GetUserCfgDir()

        configTypes=('main','extensions','highlight','keys')

        defCfgFiles={}

        usrCfgFiles={}

        for cfgType in configTypes: #build config file names

            defCfgFiles[cfgType]=os.path.join(idleDir,'config-'+cfgType+'.def')

            usrCfgFiles[cfgType]=os.path.join(userDir,'config-'+cfgType+'.cfg')

        for cfgType in configTypes: #create config parsers

            self.defaultCfg[cfgType]=IdleConfParser(defCfgFiles[cfgType])

            self.userCfg[cfgType]=IdleUserConfParser(usrCfgFiles[cfgType])

    def GetUserCfgDir(self):

        """

        Creates (if required) and returns a filesystem directory for storing

        user config files.

        """

        cfgDir = '.idlerc'

        userDir = os.path.expanduser('~')

        if userDir != '~': # expanduser() found user home dir

            if not os.path.exists(userDir):

                warn = ('\n Warning: os.path.expanduser("~") points to\n '+

                        userDir+',\n but the path does not exist.\n')

                sys.stderr.write(warn)

                userDir = '~'

        if userDir == "~": # still no path to home!

            # traditionally IDLE has defaulted to os.getcwd(), is this adequate?

            userDir = os.getcwd()

        userDir = os.path.join(userDir, cfgDir)

        if not os.path.exists(userDir):

            try:

                os.mkdir(userDir)

            except (OSError, IOError):

                warn = ('\n Warning: unable to create user config directory\n'+

                        userDir+'\n Check path and permissions.\n Exiting!\n\n')

                sys.stderr.write(warn)

                raise SystemExit

        return userDir

    def GetOption(self, configType, section, option, default=None, type=None,

                  warn_on_default=True):

        """

        Get an option value for given config type and given general

        configuration section/option or return a default. If type is specified,

        return as type. Firstly the user configuration is checked, with a

        fallback to the default configuration, and a final 'catch all'

        fallback to a useable passed-in default if the option isn't present in

        either the user or the default configuration.

        configType must be one of ('main','extensions','highlight','keys')

        If a default is returned, and warn_on_default is True, a warning is

        printed to stderr.

        """

        if self.userCfg[configType].has_option(section,option):

            return self.userCfg[configType].Get(section, option, type=type)

        elif self.defaultCfg[configType].has_option(section,option):

            return self.defaultCfg[configType].Get(section, option, type=type)

        else: #returning default, print warning

            if warn_on_default:

                warning = ('\n Warning: configHandler.py - IdleConf.GetOption -\n'

                           ' problem retrieving configration option %r\n'

                           ' from section %r.\n'

                           ' returning default value: %r\n' %

                           (option, section, default))

                sys.stderr.write(warning)

            return default

    def SetOption(self, configType, section, option, value):

        """In user's config file, set section's option to value.

        """

        self.userCfg[configType].SetOption(section, option, value)

    def GetSectionList(self, configSet, configType):

        """

        Get a list of sections from either the user or default config for

        the given config type.

        configSet must be either 'user' or 'default'

        configType must be one of ('main','extensions','highlight','keys')

        """

        if not (configType in ('main','extensions','highlight','keys')):

            raise InvalidConfigType, 'Invalid configType specified'

        if configSet == 'user':

            cfgParser=self.userCfg[configType]

        elif configSet == 'default':

            cfgParser=self.defaultCfg[configType]

        else:

            raise InvalidConfigSet, 'Invalid configSet specified'

        return cfgParser.sections()

    def GetHighlight(self, theme, element, fgBg=None):

        """

        return individual highlighting theme elements.

        fgBg - string ('fg'or'bg') or None, if None return a dictionary

        containing fg and bg colours (appropriate for passing to Tkinter in,

        e.g., a tag_config call), otherwise fg or bg colour only as specified.

        """

        if self.defaultCfg['highlight'].has_section(theme):

            themeDict=self.GetThemeDict('default',theme)

        else:

            themeDict=self.GetThemeDict('user',theme)

        fore=themeDict[element+'-foreground']

        if element=='cursor': #there is no config value for cursor bg

            back=themeDict['normal-background']

        else:

            back=themeDict[element+'-background']

        highlight={"foreground": fore,"background": back}

        if not fgBg: #return dict of both colours

            return highlight

        else: #return specified colour only

            if fgBg == 'fg':

                return highlight["foreground"]

            if fgBg == 'bg':

                return highlight["background"]

            else:

                raise InvalidFgBg, 'Invalid fgBg specified'

    def GetThemeDict(self,type,themeName):

        """

        type - string, 'default' or 'user' theme type

        themeName - string, theme name

        Returns a dictionary which holds {option:value} for each element

        in the specified theme. Values are loaded over a set of ultimate last

        fallback defaults to guarantee that all theme elements are present in

        a newly created theme.

        """

        if type == 'user':

            cfgParser=self.userCfg['highlight']

        elif type == 'default':

            cfgParser=self.defaultCfg['highlight']

        else:

            raise InvalidTheme, 'Invalid theme type specified'

        #foreground and background values are provded for each theme element

        #(apart from cursor) even though all these values are not yet used

        #by idle, to allow for their use in the future. Default values are

        #generally black and white.

        theme={ 'normal-foreground':'#000000',

                'normal-background':'#ffffff',

                'keyword-foreground':'#000000',

                'keyword-background':'#ffffff',

                'builtin-foreground':'#000000',

                'builtin-background':'#ffffff',

                'comment-foreground':'#000000',

                'comment-background':'#ffffff',

                'string-foreground':'#000000',

                'string-background':'#ffffff',

                'definition-foreground':'#000000',

                'definition-background':'#ffffff',

                'hilite-foreground':'#000000',

                'hilite-background':'gray',

                'break-foreground':'#ffffff',

                'break-background':'#000000',

                'hit-foreground':'#ffffff',

                'hit-background':'#000000',

                'error-foreground':'#ffffff',

                'error-background':'#000000',

                #cursor (only foreground can be set)

                'cursor-foreground':'#000000',

                #shell window

                'stdout-foreground':'#000000',

                'stdout-background':'#ffffff',

                'stderr-foreground':'#000000',

                'stderr-background':'#ffffff',

                'console-foreground':'#000000',

                'console-background':'#ffffff' }

        for element in theme.keys():

            if not cfgParser.has_option(themeName,element):

                #we are going to return a default, print warning

                warning=('\n Warning: configHandler.py - IdleConf.GetThemeDict'

                           ' -\n problem retrieving theme element %r'

                           '\n from theme %r.\n'

                           ' returning default value: %r\n' %

                           (element, themeName, theme[element]))

                sys.stderr.write(warning)

            colour=cfgParser.Get(themeName,element,default=theme[element])

            theme[element]=colour

        return theme

    def CurrentTheme(self):

        """

        Returns the name of the currently active theme

        """

        return self.GetOption('main','Theme','name',default='')

    def CurrentKeys(self):

        """

        Returns the name of the currently active key set

        """

        return self.GetOption('main','Keys','name',default='')

    def GetExtensions(self, active_only=True, editor_only=False, shell_only=False):

        """

        Gets a list of all idle extensions declared in the config files.

        active_only - boolean, if true only return active (enabled) extensions

        """

        extns=self.RemoveKeyBindNames(

                self.GetSectionList('default','extensions'))

        userExtns=self.RemoveKeyBindNames(

                self.GetSectionList('user','extensions'))

        for extn in userExtns:

            if extn not in extns: #user has added own extension

                extns.append(extn)

        if active_only:

            activeExtns=[]

            for extn in extns:

                if self.GetOption('extensions', extn, 'enable', default=True,

                                  type='bool'):

                    #the extension is enabled

                    if editor_only or shell_only:

                        if editor_only:

                            option = "enable_editor"

                        else:

                            option = "enable_shell"

                        if self.GetOption('extensions', extn,option,

                                          default=True, type='bool',

                                          warn_on_default=False):

                            activeExtns.append(extn)

                    else:

                        activeExtns.append(extn)

            return activeExtns

        else:

            return extns

    def RemoveKeyBindNames(self,extnNameList):

        #get rid of keybinding section names

        names=extnNameList

        kbNameIndicies=[]

        for name in names:

            if name.endswith(('_bindings', '_cfgBindings')):

                kbNameIndicies.append(names.index(name))

        kbNameIndicies.sort()

        kbNameIndicies.reverse()

        for index in kbNameIndicies: #delete each keybinding section name

            del(names[index])

        return names

    def GetExtnNameForEvent(self,virtualEvent):

        """

        Returns the name of the extension that virtualEvent is bound in, or

        None if not bound in any extension.

        virtualEvent - string, name of the virtual event to test for, without

                       the enclosing '<< >>'

        """

        extName=None

        vEvent='<<'+virtualEvent+'>>'

        for extn in self.GetExtensions(active_only=0):

            for event in self.GetExtensionKeys(extn).keys():

                if event == vEvent:

                    extName=extn

        return extName

    def GetExtensionKeys(self,extensionName):

        """

        returns a dictionary of the configurable keybindings for a particular

        extension,as they exist in the dictionary returned by GetCurrentKeySet;

        that is, where previously used bindings are disabled.

        """

        keysName=extensionName+'_cfgBindings'

        activeKeys=self.GetCurrentKeySet()

        extKeys={}

        if self.defaultCfg['extensions'].has_section(keysName):

            eventNames=self.defaultCfg['extensions'].GetOptionList(keysName)

            for eventName in eventNames:

                event='<<'+eventName+'>>'

                binding=activeKeys[event]

                extKeys[event]=binding

        return extKeys

    def __GetRawExtensionKeys(self,extensionName):

        """

        returns a dictionary of the configurable keybindings for a particular

        extension, as defined in the configuration files, or an empty dictionary

        if no bindings are found

        """

        keysName=extensionName+'_cfgBindings'

        extKeys={}

        if self.defaultCfg['extensions'].has_section(keysName):

            eventNames=self.defaultCfg['extensions'].GetOptionList(keysName)

            for eventName in eventNames:

                binding=self.GetOption('extensions',keysName,

                        eventName,default='').split()

                event='<<'+eventName+'>>'

                extKeys[event]=binding

        return extKeys

    def GetExtensionBindings(self,extensionName):

        """

        Returns a dictionary of all the event bindings for a particular

        extension. The configurable keybindings are returned as they exist in

        the dictionary returned by GetCurrentKeySet; that is, where re-used

        keybindings are disabled.

        """

        bindsName=extensionName+'_bindings'

        extBinds=self.GetExtensionKeys(extensionName)

        #add the non-configurable bindings

        if self.defaultCfg['extensions'].has_section(bindsName):

            eventNames=self.defaultCfg['extensions'].GetOptionList(bindsName)

            for eventName in eventNames:

                binding=self.GetOption('extensions',bindsName,

                        eventName,default='').split()

                event='<<'+eventName+'>>'

                extBinds[event]=binding

        return extBinds

    def GetKeyBinding(self, keySetName, eventStr):

        """

        returns the keybinding for a specific event.

        keySetName - string, name of key binding set

        eventStr - string, the virtual event we want the binding for,

                   represented as a string, eg. '<<event>>'

        """

        eventName=eventStr[2:-2] #trim off the angle brackets

        binding=self.GetOption('keys',keySetName,eventName,default='').split()

        return binding

    def GetCurrentKeySet(self):

        result = self.GetKeySet(self.CurrentKeys())

        if macosxSupport.runningAsOSXApp():

            # We're using AquaTk, replace all keybingings that use the

            # Alt key by ones that use the Option key because the former

            # don't work reliably.

            for k, v in result.items():

                v2 = [ x.replace('<Alt-', '<Option-') for x in v ]

                if v != v2:

                    result[k] = v2

        return result

    def GetKeySet(self,keySetName):

        """

        Returns a dictionary of: all requested core keybindings, plus the

        keybindings for all currently active extensions. If a binding defined

        in an extension is already in use, that binding is disabled.

        """

        keySet=self.GetCoreKeys(keySetName)

        activeExtns=self.GetExtensions(active_only=1)

        for extn in activeExtns:

            extKeys=self.__GetRawExtensionKeys(extn)

            if extKeys: #the extension defines keybindings

                for event in extKeys.keys():

                    if extKeys[event] in keySet.values():