from __future__ import unicode_literals

from django.db.models.signals import post_save
from django.utils.translation import ugettext_lazy as _

from common import (
    MayanAppConfig, menu_facet, menu_object, menu_secondary, menu_setup,
    menu_sidebar
)
from common.utils import encapsulate
from common.widgets import two_state_template
from documents.models import Document
from navigation import SourceColumn

from .handlers import launch_workflow
from .models import (
    Workflow, WorkflowInstance, WorkflowInstanceLogEntry, WorkflowState,
    WorkflowTransition
)
from .links import (
    link_document_workflow_instance_list, link_setup_workflow_document_types,
    link_setup_workflow_create, link_setup_workflow_delete,
    link_setup_workflow_edit, link_setup_workflow_list,
    link_setup_workflow_states, link_setup_workflow_state_create,
    link_setup_workflow_state_delete, link_setup_workflow_state_edit,
    link_setup_workflow_transitions, link_setup_workflow_transition_create,
    link_setup_workflow_transition_delete, link_setup_workflow_transition_edit,
    link_workflow_instance_detail, link_workflow_instance_transition
)


class DocumentStatesApp(MayanAppConfig):
    app_url = 'states'
    name = 'document_states'
    verbose_name = _('Document states')

    def ready(self):
        super(DocumentStatesApp, self).ready()

        SourceColumn(source=Workflow, label=_('Initial state'), attribute=encapsulate(lambda workflow: workflow.get_initial_state() or _('None')))

        SourceColumn(source=WorkflowInstance, label=_('Current state'), attribute='get_current_state')
        SourceColumn(source=WorkflowInstance, label=_('User'), attribute=encapsulate(lambda workflow: getattr(workflow.get_last_log_entry(), 'user', _('None'))))
        SourceColumn(source=WorkflowInstance, label=_('Last transition'), attribute='get_last_transition')
        SourceColumn(source=WorkflowInstance, label=_('Date and time'), attribute=encapsulate(lambda workflow: getattr(workflow.get_last_log_entry(), 'datetime', _('None'))))
        SourceColumn(source=WorkflowInstance, label=_('Completion'), attribute=encapsulate(lambda workflow: getattr(workflow.get_current_state(), 'completion', _('None'))))

        SourceColumn(source=WorkflowInstanceLogEntry, label=_('Date and time'), attribute='datetime')
        SourceColumn(source=WorkflowInstanceLogEntry, label=_('User'), attribute='user')
        SourceColumn(source=WorkflowInstanceLogEntry, label=_('Transition'), attribute='transition')
        SourceColumn(source=WorkflowInstanceLogEntry, label=_('Comment'), attribute='comment')

        SourceColumn(source=WorkflowState, label=_('Is initial state?'), attribute=encapsulate(lambda state: two_state_template(state.initial)))
        SourceColumn(source=WorkflowState, label=_('Completion'), attribute='completion')

        SourceColumn(source=WorkflowTransition, label=_('Origin state'), attribute='origin_state')
        SourceColumn(source=WorkflowTransition, label=_('Destination state'), attribute='destination_state')

        menu_facet.bind_links(links=[link_document_workflow_instance_list], sources=[Document])
        menu_object.bind_links(links=[link_setup_workflow_states, link_setup_workflow_transitions, link_setup_workflow_document_types, link_setup_workflow_edit, link_setup_workflow_delete], sources=[Workflow])
        menu_object.bind_links(links=[link_setup_workflow_state_edit, link_setup_workflow_state_delete], sources=[WorkflowState])
        menu_object.bind_links(links=[link_setup_workflow_transition_edit, link_setup_workflow_transition_delete], sources=[WorkflowTransition])
        menu_object.bind_links(links=[link_workflow_instance_detail, link_workflow_instance_transition], sources=[WorkflowInstance])
        menu_secondary.bind_links(links=[link_setup_workflow_list, link_setup_workflow_create], sources=[Workflow, 'document_states:setup_workflow_create', 'document_states:setup_workflow_list'])
        menu_setup.bind_links(links=[link_setup_workflow_list])
        menu_sidebar.bind_links(links=[link_setup_workflow_state_create, link_setup_workflow_transition_create], sources=[Workflow])

        post_save.connect(launch_workflow, dispatch_uid='launch_workflow', sender=Document)