"""
Copyright 2008 Free Software Foundation, Inc.
This file is part of GNU Radio

GNU Radio Companion 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.

GNU Radio Companion 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 this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
"""

import os
import subprocess
from Cheetah.Template import Template
from utils import expr_utils
from Constants import \
	TOP_BLOCK_FILE_MODE, HIER_BLOCK_FILE_MODE, \
	HIER_BLOCKS_LIB_DIR, PYEXEC, \
	FLOW_GRAPH_TEMPLATE
from utils import convert_hier

class Generator(object):

	def __init__(self, flow_graph, file_path):
		"""
		Initialize the generator object.
		Determine the file to generate.
		@param flow_graph the flow graph object
		@param file_path the path to write the file to
		"""
		self._flow_graph = flow_graph
		self._generate_options = self._flow_graph.get_option('generate_options')
		if self._generate_options == 'hb':
			self._mode = HIER_BLOCK_FILE_MODE
			dirname = HIER_BLOCKS_LIB_DIR
		else:
			self._mode = TOP_BLOCK_FILE_MODE
			dirname = os.path.dirname(file_path)
		filename = self._flow_graph.get_option('id') + '.py'
		self._file_path = os.path.join(dirname, filename)

	def get_file_path(self): return self._file_path

	def write(self):
		#generate
		open(self.get_file_path(), 'w').write(str(self))
		if self._generate_options == 'hb':
			#convert hier block to xml wrapper
			convert_hier.convert_hier(self._flow_graph, self.get_file_path())
		os.chmod(self.get_file_path(), self._mode)

	def get_popen(self):
		"""
		Execute this python flow graph.
		@return a popen object
		"""
		#execute
		cmds = [PYEXEC, '-u', self.get_file_path()] #-u is unbuffered stdio
		if self._generate_options == 'no_gui':
			cmds = ['xterm', '-e'] + cmds
		p = subprocess.Popen(args=cmds, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, shell=False, universal_newlines=True)
		return p

	def __str__(self):
		"""
		Convert the flow graph to python code.
		@return a string of python code
		"""
		imports = self._flow_graph.get_imports()
		variables = self._flow_graph.get_variables()
		parameters = self._flow_graph.get_parameters()
		#list of variables with controls
		controls = filter(lambda v: v.get_key().startswith('variable_'), variables)
		#list of blocks not including variables and imports and parameters and disabled
		blocks = sorted(self._flow_graph.get_enabled_blocks(), lambda x, y: cmp(x.get_id(), y.get_id()))
		probes = filter(lambda b: b.get_key().startswith('probe_'), blocks) #ensure probes are last in the block list
		blocks = filter(lambda b: b not in (imports + parameters + variables + probes), blocks) + probes
		#list of connections where each endpoint is enabled
		connections = self._flow_graph.get_enabled_connections()
		#list of variable names
		var_ids = [var.get_id() for var in parameters + variables]
		#list of callbacks (prepend self.)
		callbacks = [
			expr_utils.expr_prepend(cb, var_ids, 'self.')
			for cb in sum([block.get_callbacks() for block in self._flow_graph.get_enabled_blocks()], [])
		]
		#map var id to the expression (prepend self.)
		var_id2expr = dict(
			[(var.get_id(), expr_utils.expr_prepend(var.get_make().split('\n')[0], var_ids, 'self.'))
			for var in parameters + variables]
		)
		#create graph structure for variables
		variable_graph = expr_utils.get_graph(var_id2expr)
		#map var id to direct dependents
		#for each var id, make a list of all 2nd order edges
		#use all edges of that id that are not also 2nd order edges
		#meaning: list variables the ONLY depend directly on this variable
		#and not variables that also depend indirectly on this variable
		var_id2deps = dict(
			[(var_id, filter(lambda e: e not in sum([list(variable_graph.get_edges(edge))
				for edge in variable_graph.get_edges(var_id)], []), variable_graph.get_edges(var_id)
				)
			)
			for var_id in var_ids]
		)
		#map var id to callbacks
		var_id2cbs = dict(
			[(var_id, filter(lambda c: var_id in expr_utils.expr_split(c), callbacks))
			for var_id in var_ids]
		)
		#load the namespace
		namespace = {
			'imports': imports,
			'flow_graph': self._flow_graph,
			'variables': variables,
			'controls': controls,
			'parameters': parameters,
			'blocks': blocks,
			'connections': connections,
			'generate_options': self._generate_options,
			'var_id2expr': var_id2expr,
			'var_id2deps': var_id2deps,
			'var_id2cbs': var_id2cbs,
		}
		#build the template
		t = Template(open(FLOW_GRAPH_TEMPLATE, 'r').read(), namespace)
		return str(t)