#!/usr/bin/python

from sys import exit, stderr, path
from optparse import OptionParser
from glob import glob
from os.path import join as path_join, isdir, exists as path_exists, basename, dirname, normpath
from os import mkdir, system, rename
import re
from shutil import rmtree
from difflib import context_diff

class RunTests:
    def __init__(self):
        self.test_dir = dirname(__file__)
        nuface_dir = normpath(path_join(self.test_dir, '..'))
        self.nupyf = path_join(nuface_dir, "scripts/scripts/nupyf")
        nupyf_module_dir = path_join(nuface_dir, "scripts/nupyf")
        path.insert(0, nupyf_module_dir)
        self.output_dir = "/tmp/nupyf-tests"
        self.iptables = "/sbin/iptables"

    def parseOptions(self):
        parser = OptionParser(usage="%prog [-hdc] [<testcase> [<testcase> ...]]")
        parser.add_option("-d", "--delete-output", help="Does not delete output files after failed test at %s." % self.output_dir,
            action="store_false", default=True)
        parser.add_option("-c", "--continue-mode", help="Continues the test procedure even if a test fails.",
            action="store_true", default=False)
        parser.add_option("--regenerate", help="Regenerate tests instead of testing",
            action="store_true", default=False)

        self.options, self.testcases = parser.parse_args()

    def compareFiles(self, expect_dir, f):
        expected = path_join(expect_dir, basename(f))
        try:
            text1 = open(expected).readlines()[2:]
            text2 = open(f).readlines()[2:]
            diff = list(context_diff(text1, text2))
            if not diff:
                return False
        except IOError:
            if self.options.regenerate:
                # Ignore IOError on regeneration
                pass
            else:
                raise
        if self.options.regenerate:
            rename(f, expected)
            print "%s regenerated" % expected
            return False
        else:
            print "Diff in file %s" % expected
            for line in diff:
                print line.rstrip()
            return True

    def compareDirectories(self, expect_dir):
        failure = False
        if self.options.regenerate:
            if not isdir(expect_dir):
                mkdir(expect_dir)
        failure = False
        for f in glob(path_join(self.output_dir, "*")):
            failure |= self.compareFiles(expect_dir, f)
        return failure

    def testFile(self, test_dir, acl):
        if path_exists(self.output_dir):
            if isdir(self.output_dir):
                rmtree(self.output_dir)
            else:
                 print >>stderr, "%s: file already exists but is not a directory." % self.output_dir
                 exit(1)
        mkdir(self.output_dir)
        o = self.output_dir

        print "* Testing %s" % basename(acl)
        cmd = self.nupyf
        cmd += " --debug"
        cmd += " -d %s" % path_join(o, "dispatch_rules")
        cmd += " -f %s" % path_join(o, "forward_rules")
        cmd += " -i %s" % path_join(o, "input_rules")
        cmd += " -o %s" % path_join(o, "output_rules")
        cmd += " -n %s" % path_join(o, "nat_rules")
        cmd += " -m %s" % path_join(o, "mangle_rules")
        cmd += " --ulog --sortid=1"
        cmd += " --nufw"
        cmd += " --same-iface"
        cmd += " --iptables=%s" % self.iptables
        cmd += " %s %s" % (path_join(test_dir, "desc.xml"), acl)
        exit_code = system(cmd)
        failure = True
        if exit_code == 0:
            expect_dir = re.sub("^(.*)/acls_(.*)\.xml$", r'\1/expect_\2', acl)
            failure = self.compareDirectories(expect_dir)
        if not failure and self.options.delete_output:
            rmtree(self.output_dir)
        if failure:
            print "[FAIL]"
            if not self.options.continue_mode:
                exit(1)
        else:
            print "[ OK ]"
        return failure

    def runTestCase(self, directory):
        print "------------------------------------------------------------------------------"
        print "ENTERING INTO %s TESTCASE" % directory
        test_dir = directory
        if not isdir(test_dir):
            print >>stderr, "%s: no such directory." % test_dir
            return False
        desc = path_join(test_dir, "desc.xml")
        if not path_exists(desc):
            print >>stderr, "%s: file not found." % desc
            return False
        ok = True
        for acl in glob(path_join(test_dir, "acls*.xml")):
            ok &= self.testFile(test_dir, acl)
        return ok

    def main(self):
        self.parseOptions()
        if not self.testcases:
            print self.test_dir
            self.testcases = glob(path_join(self.test_dir, "*"))
            self.testcases = filter(isdir, self.testcases)

        for testcase in self.testcases:
            self.runTestCase(testcase)
        print "------------------------------------------------------------------------------"

if __name__ == "__main__":
    RunTests().main()