#!/usr/bin/env python3
#
# This file is Copyright 2010 by the GPSD project
# SPDX-License-Identifier: BSD-2-clause
"""
usage: regress-builder [-r limit] [-s seed]

Test-compile gpsd with each of every possible combination of device-driver
options, excluding stub drivers we don't support yet.  This does a good
job of catching bugs after driver API changes.

The -r option sets Monte Carlo mode (random-walk through configuration space)
and limits the number of tests.  The -s, if given, sets a seed; the default is
to seed from the system time.

If no options are given, the script performs a sequential test of all
possibilities.  This requires time on the order of 2 ** n where n is
the count of options.

***IMPORTANT***:
Not only has this program not been updated for Python 3, but it hasn't been
touched in such a long time that it still expects to use make rather than
SCons to do builds (and probably has outdated notions of the drivers as well).
Although updating it for Python 3 doesn't look too difficult, it doesn't make
sense to do so without first restoring it to correct operation with Python 2,
since the former fixes would otherwise be untestable.
"""
import getopt
import os
import sys
import time

driver_names = (
    "aivdm",
    "ashtech",
    # "earthmate",
    "evermore",
    "fv18",
    "garmin",
    "garmintxt",
    "geostar",
    "gpsclock",
    "itrax",
    "mtk3301",
    "navcom",
    "nmea",
    "ntrip",
    "oncore",
    "rtcm104v2",
    # "rtcm104v3",
    "sirf",
    "superstar2",
    # "tnt",
    "tripmate",
    "tsip",
    "ubx",
    "timing",
    "clientdebug",
    "oldstyle",
    "ntpshm",
    "pps",
    "reconfigure",
    "controlsend",
)


cyclesize = 2 ** len(driver_names)


def Sequential():
    "Generate sequential test vectors for exhaustive search."
    for i in xrange(cyclesize):
        yield i
    return


def MonteCarlo(seed):
    "Generate a random shuffle of test vectors for Monte Carlo testing."
    # All the magic here is in the choice of modulus.  Any odd number will
    # be relatively prime to any power of two and thus be sufficient to step
    # around the cycle hitting each number exactly once. We'd like adjacent
    # stops to have a large distance from each other.  Number theory says the
    # best way to do this is to choose a modulus close to cyclesize / phi,
    # where phi is the golden ratio (1 + 5**0.5)/2.
    modulus = int(cyclesize / 1.618033980)
    if modulus % 2 == 0:
        modulus += 1
    for i in xrange(cyclesize):
        yield (seed + i * modulus) % cyclesize
    return


class TestFactory:
    "Manage compilation tests."
    Preamble = '''
env     X_LIBS="" \\
        CPPFLAGS="-I/usr/local/include " \\
        LDFLAGS=" -L/usr/local/lib -g" \\
        CFLAGS="-g -O2 -W -Wall" \\
./configure --prefix=/home/gpsd --disable-shared \\
'''

    def n2v(self, n):
        "Number to test-vector"
        v = [0] * len(driver_names)
        i = 0
        while n > 0:
            v[i] = n % 2
            i += 1
            n = n >> 1
        return v

    def test_header(self, vector):
        hdr = ""
        for (i, name) in enumerate(driver_names):
            hdr += "--" + ("disable", "enable")[vector[i]] + "-" + name + " "
        return hdr[:-1]

    def make(self, vector):
        if os.system("make 2>&1 > /dev/null"):
            print("FAILED:   ", self.test_header(vector))
        else:
            print("SUCCEEDED:", self.test_header(vector))

    def configure_build(self, vector):
        test = TestFactory.Preamble
        for (i, name) in enumerate(driver_names):
            test += ("        --" + ("disable", "enable")[vector[i]] +
                     "-" + name + " \\\n")
        test += "\n"
        if os.system("(" + test + ") >/dev/null"):
            print("configure FAILED:", self.test_header(vector))
        else:
            self.make(vector)

    def filter(self, vector):
        "Tell us whether this combination needs to be tested."
        # No drivers at all won't even configure
        if vector == [0] * len(driver_names):
            return False
        compiled_in = map(lambda e: e[1], filter(lambda e: e[0],
                          zip(vector, driver_names)))

        def on(name):
            return name in compiled_in

        def off(name):
            return name not in compiled_in
        # START OF FILTERS
        #
        # Some types require NMEA support and shouldn't be built without it.
        if off("nmea") and (on("fv18") or on("earthmate") or on("tripmate")):
            return False
        # Earthmate, FV-18 and TripMate code scopes don't overlap.
        if on("fv18") + on("earthmate") + on("tripmate") not in (0, 3):
            return False
        # SiRF has no overlapping code scopes with the DLE-led protocols
        # (TSIP, Garmin, Evermore) but the DLE-led protocols have
        # overlaps in the packet sniffer.
        if on("sirf") != (on("tsip") or on("garmin") or on("evermore")):
            return False
        #
        # END OF FILTERS
        return True

    def run(self, generator, limit=cyclesize):
        expect = 0
        for i in range(cyclesize):
            if self.filter(self.n2v(i)):
                expect += 1
        print("# Expect %d of %d tests." % (expect, cyclesize))
        starttime = time.time()
        included = 0
        excluded = 0
        for n in generator:
            if limit == 0:
                return
            vector = self.n2v(n)
            if not self.filter(vector):
                print("EXCLUDED:", self.test_header(vector))
                excluded += 1
            else:
                self.configure_build(vector)
                included += 1
                limit -= 1
        elapsed = int(time.time() - starttime)
        hours = elapsed/3600
        minutes = (elapsed - (hours * 3600)) / 60
        seconds = elapsed - (hours * 3600) - (minutes * 60)
        print("%d tests, %d excluded, in %dh%dm%ds" %
              (included, excluded, hours, minutes, seconds))


if __name__ == '__main__':
    try:
        (options, arguments) = getopt.getopt(sys.argv[1:], "n:r:")
    except getopt.GetoptError, msg:
        sys.exit("regress-builder: " + str(msg))
    montecarlo = False
    limit = cyclesize
    seed = int(time.time())
    for (switch, val) in options:
        if switch == '-r':
            montecarlo = True
            limit = int(val)
        elif switch == '-s':
            montecarlo = True
            seed = int(val)
    if montecarlo:
        print("Monte Carlo test seeded with %d" % seed)
        TestFactory().run(MonteCarlo(seed), limit)
    else:
        print("Sequential compilation test")
        TestFactory().run(Sequential())
# vim: set expandtab shiftwidth=4
