#!/usr/bin/env python
#
# Copyright (C) 2011, 2012  Strahinja Val Markovic  <val@markovic.io>
#
# This file is part of YouCompleteMe.
#
# YouCompleteMe 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 3 of the License, or
# (at your option) any later version.
#
# YouCompleteMe is distributed in the hope that it will be useful,
# 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 YouCompleteMe.  If not, see <http://www.gnu.org/licenses/>.

import imp
import os
import vim
import ycm_core
from ycm import vimsupport
from ycm.completers.all.omni_completer import OmniCompleter
from ycm.completers.general.general_completer_store import GeneralCompleterStore


FILETYPE_SPECIFIC_COMPLETION_TO_DISABLE = vim.eval(
  'g:ycm_filetype_specific_completion_to_disable' )


class YouCompleteMe( object ):
  def __init__( self ):
    self.gencomp = GeneralCompleterStore()
    self.omnicomp = OmniCompleter()
    self.filetype_completers = {}


  def GetGeneralCompleter( self ):
    return self.gencomp


  def GetOmniCompleter( self ):
    return self.omnicomp


  def GetFiletypeCompleter( self ):
    filetypes = vimsupport.CurrentFiletypes()

    completers = [ self.GetFiletypeCompleterForFiletype( filetype )
                   for filetype in filetypes ]

    if not completers:
      return None

    # Try to find a native completer first
    for completer in completers:
      if completer and completer is not self.omnicomp:
        return completer

    # Return the omni completer for the first filetype
    return completers[0]


  def GetFiletypeCompleterForFiletype( self, filetype ):
    try:
      return self.filetype_completers[ filetype ]
    except KeyError:
      pass

    module_path = _PathToFiletypeCompleterPluginLoader( filetype )

    completer = None
    supported_filetypes = [ filetype ]
    if os.path.exists( module_path ):
      module = imp.load_source( filetype, module_path )
      completer = module.GetCompleter()
      if completer:
        supported_filetypes.extend( completer.SupportedFiletypes() )
    else:
      completer = self.omnicomp

    for supported_filetype in supported_filetypes:
      self.filetype_completers[ supported_filetype ] = completer
    return completer


  def ShouldUseGeneralCompleter( self, start_column ):
    return self.gencomp.ShouldUseNow( start_column )


  def ShouldUseFiletypeCompleter( self, start_column ):
    if self.FiletypeCompletionUsable():
      return self.GetFiletypeCompleter().ShouldUseNow(
        start_column )
    return False


  def NativeFiletypeCompletionAvailable( self ):
    completer = self.GetFiletypeCompleter()
    return bool( completer ) and completer is not self.omnicomp


  def FiletypeCompletionAvailable( self ):
    return bool( self.GetFiletypeCompleter() )


  def NativeFiletypeCompletionUsable( self ):
    return ( _CurrentFiletypeCompletionEnabled() and
             self.NativeFiletypeCompletionAvailable() )


  def FiletypeCompletionUsable( self ):
    return ( _CurrentFiletypeCompletionEnabled() and
             self.FiletypeCompletionAvailable() )


  def OnFileReadyToParse( self ):
    self.gencomp.OnFileReadyToParse()

    if self.FiletypeCompletionUsable():
      self.GetFiletypeCompleter().OnFileReadyToParse()


  def OnBufferUnload( self, deleted_buffer_file ):
    self.gencomp.OnBufferUnload( deleted_buffer_file )

    if self.FiletypeCompletionUsable():
      self.GetFiletypeCompleter().OnBufferUnload( deleted_buffer_file )


  def OnBufferVisit( self ):
    self.gencomp.OnBufferVisit()

    if self.FiletypeCompletionUsable():
      self.GetFiletypeCompleter().OnBufferVisit()


  def OnInsertLeave( self ):
    self.gencomp.OnInsertLeave()

    if self.FiletypeCompletionUsable():
      self.GetFiletypeCompleter().OnInsertLeave()


  def OnVimLeave( self ):
    self.gencomp.OnVimLeave()

    if self.FiletypeCompletionUsable():
      self.GetFiletypeCompleter().OnVimLeave()


  def DiagnosticsForCurrentFileReady( self ):
    if self.FiletypeCompletionUsable():
      return self.GetFiletypeCompleter().DiagnosticsForCurrentFileReady()
    return False


  def GetDiagnosticsForCurrentFile( self ):
    if self.FiletypeCompletionUsable():
      return self.GetFiletypeCompleter().GetDiagnosticsForCurrentFile()
    return []


  def ShowDetailedDiagnostic( self ):
    if self.FiletypeCompletionUsable():
      return self.GetFiletypeCompleter().ShowDetailedDiagnostic()


  def GettingCompletions( self ):
    if self.FiletypeCompletionUsable():
      return self.GetFiletypeCompleter().GettingCompletions()
    return False


  def OnCurrentIdentifierFinished( self ):
    self.gencomp.OnCurrentIdentifierFinished()

    if self.FiletypeCompletionUsable():
      self.GetFiletypeCompleter().OnCurrentIdentifierFinished()


  def DebugInfo( self ):
    completers = set( self.filetype_completers.values() )
    completers.add( self.gencomp )
    output = []
    for completer in completers:
      if not completer:
        continue
      debug = completer.DebugInfo()
      if debug:
        output.append( debug )

    has_clang_support = ycm_core.HasClangSupport()
    output.append( 'Has Clang support compiled in: {0}'.format(
      has_clang_support ) )

    if has_clang_support:
      output.append( ycm_core.ClangVersion() )

    return '\n'.join( output )


def _CurrentFiletypeCompletionEnabled():
  filetypes = vimsupport.CurrentFiletypes()
  return not all([ x in FILETYPE_SPECIFIC_COMPLETION_TO_DISABLE
                   for x in filetypes ])


def _PathToCompletersFolder():
  dir_of_current_script = os.path.dirname( os.path.abspath( __file__ ) )
  return os.path.join( dir_of_current_script, 'completers' )


def _PathToFiletypeCompleterPluginLoader( filetype ):
  return os.path.join( _PathToCompletersFolder(), filetype, 'hook.py' )