import os
import ecflow


class DefaultVariables(object):
    """Provide the setup variables for each suite"""

    def add_to(self, node):
        """Adds ECF_INCLUDE,ECF_HOME to the input node"""
        node.add_variable("ECF_INCLUDE", os.path.join(os.getenv("HOME"), "course"))
        node.add_variable("ECF_HOME", os.path.join(os.getenv("HOME"), "course"))


class BaseSuiteBuilder(object):
    """Abstract class. Add default variables to suite and enable job creation
    checking for any derived suite
    """

    def __init__(self, default_variables):
        self.defs = ecflow.Defs()
        # use derived class name as suite name
        self.suite = self.defs.add_suite(type(self).__name__)
        default_variables.add_to(self.suite)

    def _build_definition_hook(self):
        """Derived suite should override this function to build the suite
        Should not be called explicitly. How could we enforce this ?
        """
        pass

    def setup(self):
        """Template/skeleton function.
        Provides common algorithm for *all* derivatives
        Uses Hollywood principle.
        """

        # Build the suite
        self._build_definition_hook()

        # check job creation. Could use an assert
        job_check_result = self.defs.check_job_creation()
        if len(job_check_result) != 0:
            print("Job creation failed\n" + job_check_result)

        # Check trigger expressions and limit references
        print(self.defs.check())

        # Allows definition creation to be separated from the load
        # Use the class name as the name of the definition file
        self.defs.save_as_defs(type(self).__name__ + ".def")


class SuiteBuilder(BaseSuiteBuilder):
    """My example suite. Generates SuiteBuilder.def"""

    def __init__(self, default_variables):
        BaseSuiteBuilder.__init__(self, default_variables)

    def _build_definition_hook(self):
        f1 = self.suite.add_family("family")
        f1.add_task("task1")
        f1.add_task("task2")


class TestSuite(BaseSuiteBuilder):
    """My test suite. Generates TestSuite.def"""

    def __init__(self, default_variables):
        BaseSuiteBuilder.__init__(self, default_variables)

    def _build_definition_hook(self):
        self.suite.add_task("task1")


if __name__ == "__main__":

    my_suite = SuiteBuilder(DefaultVariables())
    my_suite.setup()

    my_test_suite = TestSuite(DefaultVariables())
    my_test_suite.setup()