"""Workflow for applicants.
"""
import grok
from datetime import datetime
from hurry.workflow.workflow import Transition, WorkflowState, NullCondition
from hurry.workflow.interfaces import IWorkflowState, IWorkflowTransitionEvent
from waeup.sirp.applicants.interfaces import IApplicantBaseData
from waeup.sirp.interfaces import IObjectHistory, IWAeUPWorkflowInfo
from waeup.sirp.workflow import (
    WAeUPWorkflow, WAeUPWorkflowInfo, NULL_TRANSITION)

INITIALIZED = 'initialized'
STARTED = 'started'
SUBMITTED = 'submitted'
ADMITTED = 'admitted'
NOT_ADMITTED = 'not admitted'
CREATED = 'created'

APPLICATION_TRANSISIONS = (
    NULL_TRANSITION,

    Transition(
        transition_id = 'init',
        title = 'Initialize application',
        source = None,
        condition = NullCondition,
        msg = 'application process initialized',
        destination = INITIALIZED),

    Transition(
        transition_id = 'start',
        title = 'Start application',
        msg = 'application process started',
        source = INITIALIZED,
        destination = STARTED),

    Transition(
        transition_id = 'submit',
        title = 'Submit application',
        msg = 'application record submitted',
        source = STARTED,
        destination = SUBMITTED),

    Transition(
        transition_id = 'admit',
        title = 'Admit applicant',
        msg = 'applicant admitted',
        source = SUBMITTED,
        destination = ADMITTED),

    Transition(
        transition_id = 'refuse1',
        title = 'Refuse application',
        msg = 'application refused',
        source = SUBMITTED,
        destination = NOT_ADMITTED),

    Transition(
        transition_id = 'refuse2',
        title = 'Refuse application',
        msg = 'application refused',
        source = ADMITTED,
        destination = NOT_ADMITTED),

    Transition(
        transition_id = 'create',
        title = 'Create student record',
        msg = 'student record created',
        source = ADMITTED,
        destination = CREATED),

    Transition(
        transition_id = 'reset1',
        title = 'Reset application',
        msg = 'application record reset',
        source = SUBMITTED,
        destination = STARTED),

    Transition(
        transition_id = 'reset2',
        title = 'Reset application',
        msg = 'application record reset',
        source = ADMITTED,
        destination = STARTED),

    Transition(
        transition_id = 'reset3',
        title = 'Reset application',
        msg = 'application record reset',
        source = NOT_ADMITTED,
        destination = STARTED),

    Transition(
        transition_id = 'reset4',
        title = 'Reset application',
        msg = 'application record reset',
        source = CREATED,
        destination = STARTED),
    )

application_workflow = WAeUPWorkflow(APPLICATION_TRANSISIONS)

class ApplicationWorkflowState(WorkflowState, grok.Adapter):
    """An adapter to adapt Applicant objects to workflow states.
    """
    grok.context(IApplicantBaseData)
    grok.provides(IWorkflowState)

    state_key = 'wf.application.state'
    state_id = 'wf.application.id'

class ApplicationWorkflowInfo(WAeUPWorkflowInfo, grok.Adapter):
    """Adapter to adapt Applicant objects to workflow info objects.
    """
    grok.context(IApplicantBaseData)
    grok.provides(IWAeUPWorkflowInfo)

    def __init__(self, context):
        self.context = context
        self.wf = application_workflow

@grok.subscribe(IApplicantBaseData, IWorkflowTransitionEvent)
def handle_applicant_transition_event(obj, event):
    """Append message to applicant when transition happened.
    """
    timestamp = datetime.now().strftime("%d/%m/%Y %H:%M:%S")
    msg = '%s - %s (new state: %s)' % (
        timestamp, event.transition.user_data['msg'], event.destination)
    history = IObjectHistory(obj)
    history.addMessage(msg)
    return