Port.py

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"""
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
"""
##@package grc_gnuradio.Port
#Flow graph block port (source or sink).
#@author Josh Blum

from grc.elements.Port import Port as _Port
from grc import Utils
from grc.Constants import MAX_NUM_PORTS

class Port(_Port):

        ##possible port types
        TYPES = ['complex', 'float', 'int', 'short', 'byte']

        def __init__(self, block, n):
                """
                Make a new port from nested data.
                @param block the parent element
                @param n the nested odict
                @return a new port
                """
                vlen = Utils.exists_or_else(n, 'vlen', '1')
                nports = Utils.exists_or_else(n, 'nports', '')
                optional = Utils.exists_or_else(n, 'optional', '')
                #build the port
                _Port.__init__(
                        self,
                        block=block,
                        n=n,
                )
                self._nports = nports
                self._vlen = vlen
                self._optional = bool(optional)

        def get_vlen(self):
                """
                Get the vector length.
                If the evaluation of vlen cannot be cast to an integer, return 1.
                @return the vector length or 1
                """
                vlen = self.get_parent().resolve_dependencies(self._vlen)
                try: return int(self.get_parent().get_parent().evaluate(vlen))
                except: return 1

        def get_nports(self):
                """
                Get the number of ports.
                If already blank, return a blank
                If the evaluation of nports cannot be cast to an integer, return 1.
                @return the number of ports or 1
                """
                nports = self.get_parent().resolve_dependencies(self._nports)
                #return blank if nports is blank
                if not nports: return ''
                try:
                        nports = int(self.get_parent().get_parent().evaluate(nports))
                        assert(0 < nports <= MAX_NUM_PORTS)
                        return nports
                except: return 1

        def get_optional(self): return bool(self._optional)

        def get_color(self):
                """
                Get the color that represents this port's type.
                Codes differ for ports where the vec length is 1 or greater than 1.
                @return a hex color code.
                """
                try:
                        if self.get_vlen() == 1:
                                return {#vlen is 1
                                        'complex': '#3399FF',
                                        'float': '#FF8C69',
                                        'int': '#00FF99',
                                        'short': '#FFFF66',
                                        'byte': '#FF66FF',
                                }[self.get_type()]
                        return {#vlen is non 1
                                'complex': '#3399AA',
                                'float': '#CC8C69',
                                'int': '#00CC99',
                                'short': '#CCCC33',
                                'byte': '#CC66CC',
                        }[self.get_type()]
                except: return _Port.get_color(self)

        def is_empty(self):
                """!
                Is this port empty?
                An empty port has no connections.
                Not empty of optional is set.
                @return true if empty
                """
                return not self.get_optional() and not self.get_connections()

class Source(Port):

        def __init__(self, block, n):
                self._n = n #save n
                #key is port index
                n['key'] = str(block._source_count)
                block._source_count = block._source_count + 1
                Port.__init__(self, block, n)

        def __del__(self):
                self.get_parent()._source_count = self.get_parent()._source_count - 1

class Sink(Port):

        def __init__(self, block, n):
                self._n = n #save n
                #key is port index
                n['key'] = str(block._sink_count)
                block._sink_count = block._sink_count + 1
                Port.__init__(self, block, n)

        def __del__(self):
                self.get_parent()._sink_count = self.get_parent()._sink_count - 1

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