# ==================================================================================================================== #
#            __     ___   _ ____  _     ____                                                                           #
#  _ __  _   \ \   / / | | |  _ \| |   |  _ \ __ _ _ __ ___  ___ _ __                                                  #
# | '_ \| | | \ \ / /| |_| | | | | |   | |_) / _` | '__/ __|/ _ \ '__|                                                 #
# | |_) | |_| |\ V / |  _  | |_| | |___|  __/ (_| | |  \__ \  __/ |                                                    #
# | .__/ \__, | \_/  |_| |_|____/|_____|_|   \__,_|_|  |___/\___|_|                                                    #
# |_|    |___/                                                                                                         #
# ==================================================================================================================== #
# Authors:                                                                                                             #
#   Patrick Lehmann                                                                                                    #
#                                                                                                                      #
# License:                                                                                                             #
# ==================================================================================================================== #
# Copyright 2017-2021 Patrick Lehmann - Boetzingen, Germany                                                            #
# Copyright 2016-2017 Patrick Lehmann - Dresden, Germany                                                               #
#                                                                                                                      #
# Licensed under the Apache License, Version 2.0 (the "License");                                                      #
# you may not use this file except in compliance with the License.                                                     #
# You may obtain a copy of the License at                                                                              #
#                                                                                                                      #
#   http://www.apache.org/licenses/LICENSE-2.0                                                                         #
#                                                                                                                      #
# Unless required by applicable law or agreed to in writing, software                                                  #
# distributed under the License is distributed on an "AS IS" BASIS,                                                    #
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.                                             #
# See the License for the specific language governing permissions and                                                  #
# limitations under the License.                                                                                       #
# ==================================================================================================================== #
#
from pyTooling.Decorators                   import export

from pyVHDLParser.Token                     import LinebreakToken, WordToken, SpaceToken, CommentToken, MultiLineCommentToken, IndentationToken
from pyVHDLParser.Token.Keywords            import PackageKeyword, IsKeyword, EndKeyword, BodyKeyword, FunctionKeyword, SignalKeyword
from pyVHDLParser.Token.Keywords            import BoundaryToken, IdentifierToken
from pyVHDLParser.Token.Keywords            import ConstantKeyword, SharedKeyword, ProcedureKeyword, FunctionKeyword, PureKeyword, ImpureKeyword
from pyVHDLParser.Blocks                    import BlockParserException, Block, CommentBlock, ParserState
from pyVHDLParser.Blocks.Common             import LinebreakBlock, IndentationBlock, WhitespaceBlock
from pyVHDLParser.Blocks.Generic            import SequentialDeclarativeRegion
from pyVHDLParser.Blocks.Generic1           import EndBlock as EndBlockBase


@export
class EndBlock(EndBlockBase):
	KEYWORD =             (PackageKeyword, BodyKeyword)
	KEYWORD_IS_OPTIONAL = True
	EXPECTED_NAME =       " ".join(kw.__KEYWORD__ for kw in KEYWORD)


@export
class DeclarativeRegion(SequentialDeclarativeRegion):
	END_BLOCK = EndBlock


@export
class NameBlock(Block):
	@classmethod
	def stateBodyKeyword(cls, parserState: ParserState):
		token = parserState.Token
		if isinstance(token, SpaceToken):
			parserState.NewToken =    BoundaryToken(token)
			parserState.NextState =   cls.stateWhitespace1
			return
		elif isinstance(token, (LinebreakToken, CommentToken)):
			block =                   LinebreakBlock if isinstance(token, LinebreakToken) else CommentBlock
			parserState.NewBlock =    cls(parserState.LastBlock, parserState.TokenMarker, endToken=token.PreviousToken, multiPart=True)
			_ =                       block(parserState.NewBlock, token)
			parserState.TokenMarker = None
			parserState.NextState =   cls.stateWhitespace1
			return

		raise BlockParserException("Expected whitespace after keyword ", token)

	@classmethod
	def stateWhitespace1(cls, parserState: ParserState):
		token = parserState.Token
		if isinstance(token, WordToken):
			parserState.NewToken =      IdentifierToken(token)
			parserState.NextState =     cls.statePackageName
			return
		elif isinstance(token, LinebreakToken):
			if (not (isinstance(parserState.LastBlock, CommentBlock) and isinstance(parserState.LastBlock.StartToken, MultiLineCommentToken))):
				parserState.NewBlock =    NameBlock(parserState.LastBlock, parserState.TokenMarker, endToken=token.PreviousToken, multiPart=True)
				_ =                       LinebreakBlock(parserState.NewBlock, token)
			else:
				parserState.NewBlock =    LinebreakBlock(parserState.LastBlock, token)
			parserState.TokenMarker =   None
			return
		elif isinstance(token, CommentToken):
			parserState.NewBlock =      cls(parserState.LastBlock, parserState.TokenMarker, endToken=token.PreviousToken, multiPart=True)
			_ =                         CommentBlock(parserState.NewBlock, token)
			parserState.TokenMarker =   None
			return
		elif (isinstance(token, SpaceToken) and (isinstance(parserState.LastBlock, CommentBlock) and isinstance(parserState.LastBlock.StartToken, MultiLineCommentToken))):
			parserState.NewToken =      BoundaryToken(token)
			parserState.NewBlock =      WhitespaceBlock(parserState.LastBlock, parserState.NewToken)
			parserState.TokenMarker =   None
			return

		raise BlockParserException("Expected package name (identifier).", token)

	@classmethod
	def statePackageName(cls, parserState: ParserState):
		token = parserState.Token
		if isinstance(token, SpaceToken):
			parserState.NewToken =    BoundaryToken(token)
			parserState.NextState =   cls.stateWhitespace2
			return
		elif isinstance(token, (LinebreakToken, CommentToken)):
			block =                   LinebreakBlock if isinstance(token, LinebreakToken) else CommentBlock
			parserState.NewBlock =    cls(parserState.LastBlock, parserState.TokenMarker, endToken=token.PreviousToken, multiPart=True)
			_ =                       block(parserState.NewBlock, token)
			parserState.TokenMarker = None
			parserState.NextState =   cls.stateWhitespace2
			return

		raise BlockParserException("Expected whitespace after package name.", token)

	@classmethod
	def stateWhitespace2(cls, parserState: ParserState):
		token = parserState.Token
		if (isinstance(token, WordToken) and (token <= "is")):
			parserState.NewToken =      IsKeyword(token)
			parserState.NewBlock =      NameBlock(parserState.LastBlock, parserState.TokenMarker, endToken=parserState.NewToken)
			parserState.TokenMarker =   None
			parserState.NextState =     DeclarativeRegion.stateDeclarativeRegion
			return
		elif isinstance(token, LinebreakToken):
			if (not (isinstance(parserState.LastBlock, CommentBlock) and isinstance(parserState.LastBlock.StartToken, MultiLineCommentToken))):
				parserState.NewBlock =    NameBlock(parserState.LastBlock, parserState.TokenMarker, endToken=token.PreviousToken, multiPart=True)
				_ =                       LinebreakBlock(parserState.NewBlock, token)
			else:
				parserState.NewBlock =    LinebreakBlock(parserState.LastBlock, token)
			parserState.TokenMarker =   None
			return
		elif isinstance(token, CommentToken):
			parserState.NewBlock =      cls(parserState.LastBlock, parserState.TokenMarker, endToken=token.PreviousToken, multiPart=True)
			_ =                         CommentBlock(parserState.NewBlock, token)
			parserState.TokenMarker =   None
			return
		elif (isinstance(token, SpaceToken) and (isinstance(parserState.LastBlock, CommentBlock) and isinstance(parserState.LastBlock.StartToken, MultiLineCommentToken))):
			parserState.NewToken =      BoundaryToken(token)
			parserState.NewBlock =      WhitespaceBlock(parserState.LastBlock, parserState.NewToken)
			parserState.TokenMarker =   None
			return

		raise BlockParserException("Expected keyword IS after package name.", token)
