# pylint: disable-msg=C0111
# Copyright 2008 Google Inc. Released under the GPL v2

import warnings
with warnings.catch_warnings():
    # The 'compiler' module is gone in Python 3.0.  Let's not say
    # so in every log file.
    warnings.simplefilter("ignore", DeprecationWarning)
    import compiler
import logging, textwrap

from autotest_lib.client.common_lib import enum

REQUIRED_VARS = set(['author', 'doc', 'name', 'time', 'test_type'])
OBSOLETE_VARS = set(['experimental'])

CONTROL_TYPE = enum.Enum('Server', 'Client', start_value=1)
CONTROL_TYPE_NAMES =  enum.Enum(*CONTROL_TYPE.names, string_values=True)

_SUITE_ATTRIBUTE_PREFIX = 'suite:'

class ControlVariableException(Exception):
    pass

def _validate_control_file_fields(control_file_path, control_file_vars,
                                  raise_warnings):
    """Validate the given set of variables from a control file.

    @param control_file_path: string path of the control file these were
            loaded from.
    @param control_file_vars: dict of variables set in a control file.
    @param raise_warnings: True iff we should raise on invalid variables.

    """
    diff = REQUIRED_VARS - set(control_file_vars)
    if diff:
        warning = ('WARNING: Not all required control '
                   'variables were specified in %s.  Please define '
                   '%s.') % (control_file_path, ', '.join(diff))
        if raise_warnings:
            raise ControlVariableException(warning)
        print textwrap.wrap(warning, 80)

    obsolete = OBSOLETE_VARS & set(control_file_vars)
    if obsolete:
        warning = ('WARNING: Obsolete variables were '
                   'specified in %s.  Please remove '
                   '%s.') % (control_file_path, ', '.join(obsolete))
        if raise_warnings:
            raise ControlVariableException(warning)
        print textwrap.wrap(warning, 80)


class ControlData(object):
    # Available TIME settings in control file, the list must be in lower case
    # and in ascending order, test running faster comes first.
    TEST_TIME_LIST = ['fast', 'short', 'medium', 'long', 'lengthy']
    TEST_TIME = enum.Enum(*TEST_TIME_LIST, string_values=False)

    @staticmethod
    def get_test_time_index(time):
        """
        Get the order of estimated test time, based on the TIME setting in
        Control file. Faster test gets a lower index number.
        """
        try:
            return ControlData.TEST_TIME.get_value(time.lower())
        except AttributeError:
            # Raise exception if time value is not a valid TIME setting.
            error_msg = '%s is not a valid TIME.' % time
            logging.error(error_msg)
            raise ControlVariableException(error_msg)


    def __init__(self, vars, path, raise_warnings=False):
        # Defaults
        self.path = path
        self.dependencies = set()
        # TODO(jrbarnette): This should be removed once outside
        # code that uses can be changed.
        self.experimental = False
        self.run_verify = True
        self.sync_count = 1
        self.test_parameters = set()
        self.test_category = ''
        self.test_class = ''
        self.retries = 0
        self.job_retries = 0
        # Default to require server-side package. Unless require_ssp is
        # explicitly set to False, server-side package will be used for the
        # job. This can be overridden by global config
        # AUTOSERV/enable_ssp_container
        self.require_ssp = None
        self.attributes = set()

        _validate_control_file_fields(self.path, vars, raise_warnings)

        for key, val in vars.iteritems():
            try:
                self.set_attr(key, val, raise_warnings)
            except Exception, e:
                if raise_warnings:
                    raise
                print 'WARNING: %s; skipping' % e

        self._patch_up_suites_from_attributes()


    def set_attr(self, attr, val, raise_warnings=False):
        attr = attr.lower()
        try:
            set_fn = getattr(self, 'set_%s' % attr)
            set_fn(val)
        except AttributeError:
            # This must not be a variable we care about
            pass


    def _patch_up_suites_from_attributes(self):
        """Patch up the set of suites this test is part of.

        Legacy builds will not have an appropriate ATTRIBUTES field set.
        Take the union of suites specified via ATTRIBUTES and suites specified
        via SUITE.

        SUITE used to be its own variable, but now suites are taken only from
        the attributes.

        """

        suite_names = set()
        # Extract any suites we know ourselves to be in based on the SUITE
        # line.  This line is deprecated, but control files in old builds will
        # still have it.
        if hasattr(self, 'suite'):
            existing_suites = self.suite.split(',')
            existing_suites = [name.strip() for name in existing_suites]
            existing_suites = [name for name in existing_suites if name]
            suite_names.update(existing_suites)

        # Figure out if our attributes mention any suites.
        for attribute in self.attributes:
            if not attribute.startswith(_SUITE_ATTRIBUTE_PREFIX):
                continue
            suite_name = attribute[len(_SUITE_ATTRIBUTE_PREFIX):]
            suite_names.add(suite_name)

        # Rebuild the suite field if necessary.
        if suite_names:
            self.set_suite(','.join(sorted(list(suite_names))))


    def _set_string(self, attr, val):
        val = str(val)
        setattr(self, attr, val)


    def _set_option(self, attr, val, options):
        val = str(val)
        if val.lower() not in [x.lower() for x in options]:
            raise ValueError("%s must be one of the following "
                             "options: %s" % (attr,
                             ', '.join(options)))
        setattr(self, attr, val)


    def _set_bool(self, attr, val):
        val = str(val).lower()
        if val == "false":
            val = False
        elif val == "true":
            val = True
        else:
            msg = "%s must be either true or false" % attr
            raise ValueError(msg)
        setattr(self, attr, val)


    def _set_int(self, attr, val, min=None, max=None):
        val = int(val)
        if min is not None and min > val:
            raise ValueError("%s is %d, which is below the "
                             "minimum of %d" % (attr, val, min))
        if max is not None and max < val:
            raise ValueError("%s is %d, which is above the "
                             "maximum of %d" % (attr, val, max))
        setattr(self, attr, val)


    def _set_set(self, attr, val):
        val = str(val)
        items = [x.strip() for x in val.split(',') if x.strip()]
        setattr(self, attr, set(items))


    def set_author(self, val):
        self._set_string('author', val)


    def set_dependencies(self, val):
        self._set_set('dependencies', val)


    def set_doc(self, val):
        self._set_string('doc', val)


    def set_name(self, val):
        self._set_string('name', val)


    def set_run_verify(self, val):
        self._set_bool('run_verify', val)


    def set_sync_count(self, val):
        self._set_int('sync_count', val, min=1)


    def set_suite(self, val):
        self._set_string('suite', val)


    def set_time(self, val):
        self._set_option('time', val, ControlData.TEST_TIME_LIST)


    def set_test_class(self, val):
        self._set_string('test_class', val.lower())


    def set_test_category(self, val):
        self._set_string('test_category', val.lower())


    def set_test_type(self, val):
        self._set_option('test_type', val, list(CONTROL_TYPE.names))


    def set_test_parameters(self, val):
        self._set_set('test_parameters', val)


    def set_retries(self, val):
        self._set_int('retries', val)


    def set_job_retries(self, val):
        self._set_int('job_retries', val)


    def set_bug_template(self, val):
        if type(val) == dict:
            setattr(self, 'bug_template', val)


    def set_require_ssp(self, val):
        self._set_bool('require_ssp', val)


    def set_build(self, val):
        self._set_string('build', val)


    def set_builds(self, val):
        if type(val) == dict:
            setattr(self, 'builds', val)

    def set_attributes(self, val):
        # Add subsystem:default if subsystem is not specified.
        self._set_set('attributes', val)
        if not any(a.startswith('subsystem') for a in self.attributes):
            self.attributes.add('subsystem:default')


def _extract_const(expr):
    assert(expr.__class__ == compiler.ast.Const)
    assert(expr.value.__class__ in (str, int, float, unicode))
    return str(expr.value).strip()


def _extract_dict(expr):
    assert(expr.__class__ == compiler.ast.Dict)
    assert(expr.items.__class__ == list)
    cf_dict = {}
    for key, value in expr.items:
        try:
            key = _extract_const(key)
            val = _extract_expression(value)
        except (AssertionError, ValueError):
            pass
        else:
            cf_dict[key] = val
    return cf_dict


def _extract_list(expr):
    assert(expr.__class__ == compiler.ast.List)
    list_values = []
    for value in expr.nodes:
        try:
            list_values.append(_extract_expression(value))
        except (AssertionError, ValueError):
            pass
    return list_values


def _extract_name(expr):
    assert(expr.__class__ == compiler.ast.Name)
    assert(expr.name in ('False', 'True', 'None'))
    return str(expr.name)


def _extract_expression(expr):
    if expr.__class__ == compiler.ast.Const:
        return _extract_const(expr)
    if expr.__class__ == compiler.ast.Name:
        return _extract_name(expr)
    if expr.__class__ == compiler.ast.Dict:
        return _extract_dict(expr)
    if expr.__class__ == compiler.ast.List:
        return _extract_list(expr)
    raise ValueError('Unknown rval %s' % expr)


def _extract_assignment(n):
    assert(n.__class__ == compiler.ast.Assign)
    assert(n.nodes.__class__ == list)
    assert(len(n.nodes) == 1)
    assert(n.nodes[0].__class__ == compiler.ast.AssName)
    assert(n.nodes[0].flags.__class__ == str)
    assert(n.nodes[0].name.__class__ == str)

    val = _extract_expression(n.expr)
    key = n.nodes[0].name.lower()

    return (key, val)


def parse_control_string(control, raise_warnings=False, path=''):
    """Parse a control file from a string.

    @param control: string containing the text of a control file.
    @param raise_warnings: True iff ControlData should raise an error on
            warnings about control file contents.
    @param path: string path to the control file.

    """
    try:
        mod = compiler.parse(control)
    except SyntaxError, e:
        raise ControlVariableException("Error parsing data because %s" % e)
    return finish_parse(mod, path, raise_warnings)


def parse_control(path, raise_warnings=False):
    try:
        mod = compiler.parseFile(path)
    except SyntaxError, e:
        raise ControlVariableException("Error parsing %s because %s" %
                                       (path, e))
    return finish_parse(mod, path, raise_warnings)


def finish_parse(mod, path, raise_warnings):
    assert(mod.__class__ == compiler.ast.Module)
    assert(mod.node.__class__ == compiler.ast.Stmt)
    assert(mod.node.nodes.__class__ == list)

    vars = {}
    for n in mod.node.nodes:
        try:
            key, val = _extract_assignment(n)
            vars[key] = val
        except (AssertionError, ValueError):
            pass
    return ControlData(vars, path, raise_warnings)