path: root/jsongen.py

#!/usr/bin/env python
#
# Never hand-hack what you can generate...
#
# This code generates template declarations for AIS-JSON parsing from a
# declarative specification of a JSON structure - and generates those
# declarative specification from the Python format strings for
# dumping the structures
#
import sys, getopt

#
# Here is the information that makes it all work - attribute, type, and
# defult information for all fields.  We can generate either a JSON
# parser template spec or the C code for the correspondong dump functio
# from this information. Doing it this way guarantees consistency.
#
ais_specs = (
    {
    "initname" : "json_ais1",
    "header": "\tAIS_HEADER,",
    "structname": "ais->type1",
    "fieldmap":(
        # fieldname   type        default
        ('status',   'uinteger', '0'),
        ('turn',     'integer',  'AIS_TURN_NOT_AVAILABLE'),
        ('speed',    'uinteger', 'AIS_SPEED_NOT_AVAILABLE'),
        ('accuracy', 'boolean',  'false'),
        ('lon',      'integer',  'AIS_LON_NOT_AVAILABLE'),
        ('lat',      'integer',  'AIS_LAT_NOT_AVAILABLE'),
        ('course',   'uinteger', 'AIS_COURSE_NOT_AVAILABLE'),
        ('heading',  'uinteger', 'AIS_HEADING_NOT_AVAILABLE'),
        ('second',   'uinteger', 'AIS_SEC_NOT_AVAILABLE'),
        ('maneuver', 'uinteger', 'AIS_SEC_INOPERATIVE'),
        ('raim',     'boolean',  'false'),
        ('radio',    'uinteger', '0'),
        ),
    },
    # Message types 2 and 3 duplicate 1
    {
    "initname" : "json_ais4",
    "header": "\tAIS_HEADER,",
    "structname": "ais->type4",
    "fieldmap":(
        # fieldname   type        default
        ('timestamp', 'string',   None),
        ('accuracy',  'boolean',  "true"),
        ('lon',       'integer',  "AIS_LON_NOT_AVAILABLE"),
        ('lat',       'integer',  "AIS_LAT_NOT_AVAILABLE"),
        ('epfd',      'uinteger', "0"),
        ('raim',      'boolean',  "false"),
        ('radio',     'uinteger', "0"),
        ),
    "stringbuffered":("timestamp",),
    },
    {
    "initname" : "json_ais5",
    "header": "\tAIS_HEADER,",
    "structname": "ais->type5",
    "fieldmap":(
        # fieldname        type            default
        ('imo',           'uinteger',      '0'),
        ('ais_version',   'uinteger',      '0'),
        ('callsign',      'string',        None),
        ('shipname',      'string',        None),
        ('shiptype',      'uinteger',      '0'),
        ('to_bow',        'uinteger',      '0'),
        ('to_stern',      'uinteger',      '0'),
        ('to_port',       'uinteger',      '0'),
        ('to_starboard',  'uinteger',      '0'),
        ('epfd',          'uinteger',      '0'),
        ('eta',           'string',        None),
        ('draught',       'uinteger',      '0'),
        ('destination',   'string',        None),
        ('dte',           'uinteger',      '1'),
        ),
    "stringbuffered":("eta",),
    },
    {
    "initname" : "json_ais6",
    "header": "\tAIS_HEADER,",
    "structname": "ais->type6",
    "fieldmap":(
        # fieldname       type             default
        ('seqno',         'uinteger',      '0'),
        ('dest_mmsi',     'uinteger',      '0'),
        ('retransmit',    'boolean',       'false'),
        ('app_id',        'uinteger',      '0'),
        ('data',          'string',        None),
        ),
    "stringbuffered":("data",),
    },
    {
    "initname" : "json_ais7",
    "header": "\tAIS_HEADER,",
    "structname": "ais->type7",
    "fieldmap":(
        # fieldname       type             default
        ('mmsi1',         'uinteger',      '0'),
        ('mmsi2',         'uinteger',      '0'),
        ('mmsi3',         'uinteger',      '0'),
        ('mmsi4',         'uinteger',      '0'),
        ),
    },
    {
    "initname" : "json_ais8",
    "header": "\tAIS_HEADER,",
    "structname": "ais->type8",
    "fieldmap":(
        # fieldname       type             default
        ('app_id',        'uinteger',      '0'),
        ('data',          'string',        None),
        ),
    "stringbuffered":("data",),
    },
    {
    "initname" : "json_ais9",
    "header": "\tAIS_HEADER,",
    "structname": "ais->type9",
    "fieldmap":(
        # fieldname       type             default
        ('alt',           'uinteger',      'AIS_ALT_NOT_AVAILABLE'),
        ('speed',         'uinteger',      'AIS_SPEED_NOT_AVAILABLE'),
        ('accuracy',      'boolean',       'false'),
        ('lon',           'integer',       'AIS_LON_NOT_AVAILABLE'),
        ('lat',           'integer',       'AIS_LAT_NOT_AVAILABLE'),
        ('course',        'uinteger',      'AIS_COURSE_NOT_AVAILABLE'),
        ('second',        'uinteger',      'AIS_SEC_NOT_AVAILABLE'),
        ('regional',      'uinteger',      '0'),
        ('dte',           'uinteger',      '1'),
        ('raim',          'boolean',       'false'),
        ('radio',         'uinteger',      '0'),
        ),
    },
    {
    "initname" : "json_ais10",
    "header": "\tAIS_HEADER,",
    "structname": "ais->type10",
    "fieldmap":(
        # fieldname       type             default
        ('dest_mmsi',     'uinteger',      '0'),
        ),
    },
    # Message type 11 duplicates 4
    {
    "initname" : "json_ais12",
    "header": "\tAIS_HEADER,",
    "structname": "ais->type12",
    "fieldmap":(
        # fieldname       type             default
        ('seqno',         'uinteger',      '0'),
        ('dest_mmsi',     'uinteger',      '0'),
        ('retransmit',    'boolean',       '0'),
        ('text',          'string',        None),
        ),
    },
    # Message type 13 duplicates 7 
    {
    "initname" : "json_ais14",
    "header": "\tAIS_HEADER,",
    "structname": "ais->type14",
    "fieldmap":(
        # fieldname       type             default
        ('text',          'string',        None),
        ),
    },
    {
    "initname" : "json_ais15",
    "header": "\tAIS_HEADER,",
    "structname": "ais->type15",
    "fieldmap":(
        # fieldname       type             default
        ('mmsi1',         'uinteger',      '0'),
        ('type1_1',       'uinteger',      '0'),
        ('offset1_1',     'uinteger',      '0'),
        ('type1_2',       'uinteger',      '0'),
        ('offset1_2',     'uinteger',      '0'),
        ('mmsi2',         'uinteger',      '0'),
        ('type2_1',       'uinteger',      '0'),
        ('offset2_1',     'uinteger',      '0'),
        ),
    },
    {
    "initname" : "json_ais16",
    "header": "\tAIS_HEADER,",
    "structname": "ais->type16",
    "fieldmap":(
        # fieldname       type             default
        ('mmsi1',         'uinteger',      '0'),
        ('offset1',       'uinteger',      '0'),
        ('increment1',    'uinteger',      '0'),
        ('mmsi2',         'uinteger',      '0'),
        ('offset2',       'uinteger',      '0'),
        ('increment2',    'uinteger',      '0'),
        ),
    },
    {
    "initname" : "json_ais17",
    "header": "\tAIS_HEADER,",
    "structname": "ais->type17",
    "fieldmap":(
        # fieldname       type             default
        ('lon',           'integer',       'AIS_GNS_LON_NOT_AVAILABLE'),
        ('lat',           'integer',       'AIS_GNS_LAT_NOT_AVAILABLE'),
        ('data',          'string',        None),
        ),
    "stringbuffered":("data",),
    },
    {
    "initname" : "json_ais18",
    "header": "\tAIS_HEADER,",
    "structname": "ais->type18",
    "fieldmap":(
        # fieldname       type             default
        ('reserved',      'uinteger',      '0'),
        ('speed',         'uinteger',      'AIS_SPEED_NOT_AVAILABLE'),
        ('accuracy',      'boolean',       'false'),
        ('lon',           'integer',       'AIS_LON_NOT_AVAILABLE'),
        ('lat',           'integer',       'AIS_LAT_NOT_AVAILABLE'),
        ('course',        'uinteger',      'AIS_COURSE_NOT_AVAILABLE'),
        ('heading',       'uinteger',      'AIS_HEADING_NOT_AVAILABLE'),
        ('second',        'uinteger',      'AIS_SEC_NOT_AVAILABLE'),
        ('regional',      'uinteger',      '0'),
        ('cs',            'boolean',       'false'),
        ('display',       'boolean',       'false'),
        ('dsc',           'boolean',       'false'),
        ('band',          'boolean',       'false'),
        ('msg22',         'boolean',       'false'),
        ('raim',          'boolean',       'false'),
        ('radio',         'uinteger',      '0'),
        ),
    },
    {
    "initname" : "json_ais19",
    "header": "\tAIS_HEADER,",
    "structname": "ais->type19",
    "fieldmap":(
        # fieldname       type             default
        ('reserved',      'uinteger',      '0'),
        ('speed',         'uinteger',      'AIS_SPEED_NOT_AVAILABLE'),
        ('accuracy',      'boolean',       'false'),
        ('lon',           'integer',       'AIS_LON_NOT_AVAILABLE'),
        ('lat',           'integer',       'AIS_LAT_NOT_AVAILABLE'),
        ('course',        'uinteger',      'AIS_COURSE_NOT_AVAILABLE'),
        ('heading',       'uinteger',      'AIS_HEADING_NOT_AVAILABLE'),
        ('second',        'uinteger',      'AIS_SEC_NOT_AVAILABLE'),
        ('regional',      'uinteger',      '0'),
        ('shipname',      'string',        None),
        ('shiptype',      'uinteger',      '0'),
        ('to_bow',        'uinteger',      '0'),
        ('to_stern',      'uinteger',      '0'),
        ('to_port',       'uinteger',      '0'),
        ('to_starboard',  'uinteger',      '0'),
        ('epfd',          'uinteger',      '0'),
        ('raim',          'boolean',       'false'),
        ('dte',           'uinteger',      '1'),
        ('assigned',      'boolean',       'false'),
        ),
    },
    {
    "initname" : "json_ais20",
    "header": "\tAIS_HEADER,",
    "structname": "ais->type20",
    "fieldmap":(
        # fieldname       type             default
        ('offset1',       'uinteger',      '0'),
        ('number1',       'uinteger',      '0'),
        ('timeout1',      'uinteger',      '0'),
        ('increment1',    'uinteger',      '0'),
        ('offset2',       'uinteger',      '0'),
        ('number2',       'uinteger',      '0'),
        ('timeout2',      'uinteger',      '0'),
        ('increment2',    'uinteger',      '0'),
        ('offset3',       'uinteger',      '0'),
        ('number3',       'uinteger',      '0'),
        ('timeout3',      'uinteger',      '0'),
        ('increment3',    'uinteger',      '0'),
        ('offset4',       'uinteger',      '0'),
        ('number4',       'uinteger',      '0'),
        ('timeout4',      'uinteger',      '0'),
        ('increment4',    'uinteger',      '0'),
        ),
    },
    {
    "initname" : "json_ais21",
    "header": "\tAIS_HEADER,",
    "structname": "ais->type21",
    "fieldmap":(
        # fieldname       type             default
        ('type',          'uinteger',      '0'),
        ('name',          'string',        None),
        ('accuracy',      'boolean',       'false'),
        ('lon',           'integer',       'AIS_LON_NOT_AVAILABLE'),
        ('lat',           'integer',       'AIS_LAT_NOT_AVAILABLE'),
        ('to_bow',        'uinteger',      '0'),
        ('to_stern',      'uinteger',      '0'),
        ('to_port',       'uinteger',      '0'),
        ('to_starboard',  'uinteger',      '0'),
        ('epfd',          'uinteger',      '0'),
        ('second',        'uinteger',      '0'),
        ('regional',      'uinteger',      '0'),
        ('off_position',  'boolean',       'false'),
        ('raim',          'boolean',       'false'),
        ('virtual_aid',   'boolean',       'false'),
        ),
    },
    {
    "initname" : "json_ais22",
    "header": "\tAIS_HEADER,",
    "structname": "ais->type22",
    "fieldmap":(
        # fieldname       type             default
        ('channel_a',     'uinteger',      '0'),
        ('channel_b',     'uinteger',      '0'),
        ('mode',          'uinteger',      '0'),
        ('power',         'boolean',       'false'),
        ('ne_lon',        'integer',       'AIS_GNS_LON_NOT_AVAILABLE'),
        ('ne_lat',        'integer',       'AIS_GNS_LAT_NOT_AVAILABLE'),
        ('sw_lon',        'integer',       'AIS_GNS_LON_NOT_AVAILABLE'),
        ('sw_lat',        'integer',       'AIS_GNS_LAT_NOT_AVAILABLE'),
        ('addressed',     'boolean',       'false'),
        ('band_a',        'boolean',       'false'),
        ('band_b',        'boolean',       'false'),
        ('zonesize',      'uinteger',      '0'),
        ),
    },
    # Structure of mesage 23 is a mystery
    {
    "initname" : "json_ais24",
    "header": "\tAIS_HEADER,",
    "structname": "ais->type24",
    "fieldmap":(
        # fieldname             type             default
        ('part',                'uinteger',      '0'),
        ('a.shipname',          'string',        None),	# Part A
        ('b.shiptype',          'uinteger',      '0'),	# Part B
        ('b.vendorid',          'string',        None),	# Part B
        ('b.callsign',          'string',        None),	# Part B
        ('b.mothership_mmsi',   'uinteger',      '0'),	# Part B
        ('b.dim.to_bow',        'uinteger',      '0'),	# Part B
        ('b.dim.to_stern',      'uinteger',      '0'),	# Part B
        ('b.dim.to_port',       'uinteger',      '0'),	# Part B
        ('b.dim.to_starboard',  'uinteger',      '0'),	# Part B
        ),
    },
)


# Give this global the string spec you need to convert with -g
# We do it this mildly odd way only because passing Python multiline
# string literals on the command line is inconvenient.
stringspec = ""

# You should not need to modify anything below this line.

def generate(spec):
    global outboard
    for (attr, itype, default) in spec["fieldmap"]:
        if attr in spec.get("stringbuffered", []):
            if attr not in outboard:
                print "    char %s[JSON_VAL_MAX+1];" % attr
                outboard.append(attr)
    print "    const struct json_attr_t %s[] = {" % spec["initname"]
    if "header" in spec:
        print spec["header"]
    for (attr, itype, default) in spec["fieldmap"]:
        structname = spec["structname"]
        if itype == "string":
            deref = ""
        else:
            deref = "&"
        if attr in spec.get("stringbuffered", []):
            target = attr
        else:
            target = structname + "." + attr
        if "." in attr:
            attr = attr[attr.rfind(".")+1:]
        print '\t{"%s",%s%s,%s.addr.%s = %s%s,' % \
               (attr, " "*(12-len(attr)), itype, " "*(10-len(itype)), itype, deref, target)
        leader = " " * 35
        if itype == "string":
            print leader + ".len = sizeof(%s)}," % target
        else:
            print leader + ".dflt.%s = %s}," % (itype, default)

    print """\
	{NULL},
    };
"""

# No code for gernerating dump functions yet.
# When we do this, remembeer that we have to suppress dump function
# generation from any spec with a union dot in the field names;
# those will have to be coded by hand.

def string_to_specifier(strspec):
    "Compile a Python-style format string to an attribute-type fieldmap."
    # Map C and Python-type format letters to JSON parser datatypes 
    fmtmap = {
        "d": "integer",
        "u": "uinteger",
        "f": "real",
        "s": "boolean",	# Only booleans print as unquoted strings
        "\"": "string",
        }
    dftmap = {
        "integer":  "0",
        "uinteger": "0",
        "real":     "0.0",
        "string":   None,
        "boolean":  "false"
        }
    strspec = strspec.strip()
    if strspec[-1] == "}":
        strspec = strspec[:-1]
    else:
        print "Missing terminating }"
        sys.exit(1)
    print '    "fieldmap":('
    for item in strspec.split(","):
        itype = fmtmap[item[-1]]
        attr = item[:item.find(":")]
        if attr[0] == '"':
            attr = attr[1:]
        if attr[-1] == '"':
            attr = attr[:-1]
        dflt = dftmap[itype]
        if dflt is not None:
            dflt = `dflt`
        print "        ('%s',%s'%s',%s%s)," % (attr, " "*(14-len(attr)), itype, " "*(14-len(itype)), dflt)
    print "        )"


if __name__ == '__main__':
    try:
        # The --ais and --target= options are (required) placeho;lders.
        # In the future, this script will generate more different kinds
        # of code.
        (options, arguments) = getopt.getopt(sys.argv[1:], "g", ["ais", "target="])
    except getopt.GetoptError, msg:
        print "jsongen.py: " + str(msg)
        raise SystemExit, 1

    specify = False
    spec = None
    target = None
    for (switch, val) in options:
        if switch == '-g':
            specify = True
        elif switch == '--ais':
            spec = ais_specs
        elif switch == '--target':
            target = val

    if not specify and (not target or not spec):
        print "jsongen.py: must specify type and target."
        sys,exit(1)


    if specify:
        string_to_specifier(stringspec)
    else:
        print """/*
 * This is code generated by jsongen.py. Do not hand-hack it!
 */
"""
        outboard = []
        for description in spec:
            generate(description)
        print "/* Generated code ends. */"