from galaxy.web.base.controller import *

import pkg_resources
pkg_resources.require( "simplejson" )
import simplejson

from galaxy.web.framework.helpers import time_ago, iff, grids
from galaxy.tools.parameters import *
from galaxy.tools import DefaultToolState
from galaxy.tools.parameters.grouping import Repeat, Conditional
from galaxy.datatypes.data import Data
from galaxy.util.odict import odict
from galaxy.util.bunch import Bunch
from galaxy.util.sanitize_html import sanitize_html
from galaxy.util.topsort import topsort, topsort_levels, CycleError
from galaxy.workflow.modules import *
from galaxy import model
from galaxy.model.mapping import desc
from galaxy.model.orm import *
from galaxy.jobs.actions.post import *
from galaxy.item_attrs.ratings import UsesItemRatings

import urllib2

class StoredWorkflowListGrid( grids.Grid ):    
    class StepsColumn( grids.GridColumn ):
        def get_value(self, trans, grid, workflow):
            return len( workflow.latest_workflow.steps )
    
    # Grid definition
    use_panels = True
    title = "Saved Workflows"
    model_class = model.StoredWorkflow
    default_filter = { "name" : "All", "tags": "All" }
    default_sort_key = "-update_time"
    columns = [
        grids.TextColumn( "Name", key="name", model_class=model.StoredWorkflow, attach_popup=True, filterable="advanced" ),
        grids.IndividualTagsColumn( "Tags", "tags", model.StoredWorkflow, model.StoredWorkflowTagAssociation, filterable="advanced", grid_name="StoredWorkflowListGrid" ),
        StepsColumn( "Steps" ),
        grids.GridColumn( "Created", key="create_time", format=time_ago ),
        grids.GridColumn( "Last Updated", key="update_time", format=time_ago ),
    ]
    columns.append( 
        grids.MulticolFilterColumn(  
        "Search", 
        cols_to_filter=[ columns[0], columns[1] ], 
        key="free-text-search", visible=False, filterable="standard" )
                )
    operations = [
        grids.GridOperation( "Edit", allow_multiple=False, condition=( lambda item: not item.deleted ), async_compatible=False ),
        grids.GridOperation( "Run", condition=( lambda item: not item.deleted ), async_compatible=False ),
        grids.GridOperation( "Clone", condition=( lambda item: not item.deleted ), async_compatible=False  ),
        grids.GridOperation( "Rename", condition=( lambda item: not item.deleted ), async_compatible=False  ),
        grids.GridOperation( "Sharing", condition=( lambda item: not item.deleted ), async_compatible=False ),
        grids.GridOperation( "Delete", condition=( lambda item: item.deleted ), async_compatible=True ),
    ]
    def apply_query_filter( self, trans, query, **kwargs ):
        return query.filter_by( user=trans.user, deleted=False )

class StoredWorkflowAllPublishedGrid( grids.Grid ):
    title = "Published Workflows"
    model_class = model.StoredWorkflow
    default_sort_key = "-update_time"
    default_filter = dict( public_url="All", username="All", tags="All" )
    use_async = True
    columns = [
        grids.PublicURLColumn( "Name", key="name", model_class=model.StoredWorkflow, filterable="advanced" ),
        grids.OwnerAnnotationColumn( "Annotation", key="annotation", model_class=model.StoredWorkflow, model_annotation_association_class=model.StoredWorkflowAnnotationAssociation, filterable="advanced" ),
        grids.OwnerColumn( "Owner", key="username", model_class=model.User, filterable="advanced", sortable=False ), 
        grids.CommunityTagsColumn( "Community Tags", "tags", model.StoredWorkflow, model.StoredWorkflowTagAssociation, filterable="advanced", grid_name="PublicWorkflowListGrid" ),
        grids.GridColumn( "Last Updated", key="update_time", format=time_ago )
    ]
    columns.append( 
        grids.MulticolFilterColumn(  
        "Search", 
        cols_to_filter=[ columns[0], columns[1], columns[2] ], 
        key="free-text-search", visible=False, filterable="standard" )
                )
    operations = []
    def build_initial_query( self, trans, **kwargs ):
        # Join so that searching stored_workflow.user makes sense.
        return trans.sa_session.query( self.model_class ).join( model.User.table )
    def apply_query_filter( self, trans, query, **kwargs ):
        # A public workflow is published, has a slug, and is not deleted.
        return query.filter( self.model_class.published==True ).filter( self.model_class.slug != None ).filter( self.model_class.deleted == False )

class WorkflowController( BaseController, Sharable, UsesStoredWorkflow, UsesAnnotations, UsesItemRatings ):
    stored_list_grid = StoredWorkflowListGrid()
    published_list_grid = StoredWorkflowAllPublishedGrid()
    
    @web.expose
    def index( self, trans ):
        return self.list( trans )
        
    @web.expose
    @web.require_login( "use Galaxy workflows" )
    def list_grid( self, trans, **kwargs ):
        """ List user's stored workflows. """
        status = message = None
        if 'operation' in kwargs:
            operation = kwargs['operation'].lower()
            if operation == "rename":
                return self.rename( trans, **kwargs )
            history_ids = util.listify( kwargs.get( 'id', [] ) )
            if operation == "sharing":
                return self.sharing( trans, id=history_ids )
        return self.stored_list_grid( trans, **kwargs )
                                   
    @web.expose
    @web.require_login( "use Galaxy workflows", use_panels=True )
    def list( self, trans ):
        """
        Render workflow main page (management of existing workflows)
        """
        user = trans.get_user()
        workflows = trans.sa_session.query( model.StoredWorkflow ) \
            .filter_by( user=user, deleted=False ) \
            .order_by( desc( model.StoredWorkflow.table.c.update_time ) ) \
            .all()
        shared_by_others = trans.sa_session \
            .query( model.StoredWorkflowUserShareAssociation ) \
            .filter_by( user=user ) \
            .join( 'stored_workflow' ) \
            .filter( model.StoredWorkflow.deleted == False ) \
            .order_by( desc( model.StoredWorkflow.update_time ) ) \
            .all()
            
        # Legacy issue: all shared workflows must have slugs.
        slug_set = False
        for workflow_assoc in shared_by_others:
            slug_set = self.create_item_slug( trans.sa_session, workflow_assoc.stored_workflow )
        if slug_set:
            trans.sa_session.flush()

        return trans.fill_template( "workflow/list.mako",
                                    workflows = workflows,
                                    shared_by_others = shared_by_others )
    
    @web.expose
    @web.require_login( "use Galaxy workflows" )
    def list_for_run( self, trans ):
        """
        Render workflow list for analysis view (just allows running workflow
        or switching to management view)
        """
        user = trans.get_user()
        workflows = trans.sa_session.query( model.StoredWorkflow ) \
            .filter_by( user=user, deleted=False ) \
            .order_by( desc( model.StoredWorkflow.table.c.update_time ) ) \
            .all()
        shared_by_others = trans.sa_session \
            .query( model.StoredWorkflowUserShareAssociation ) \
            .filter_by( user=user ) \
            .filter( model.StoredWorkflow.deleted == False ) \
            .order_by( desc( model.StoredWorkflow.table.c.update_time ) ) \
            .all()
        return trans.fill_template( "workflow/list_for_run.mako",
                                    workflows = workflows,
                                    shared_by_others = shared_by_others )
                                    
    @web.expose
    def list_published( self, trans, **kwargs ):
        grid = self.published_list_grid( trans, **kwargs )
        if 'async' in kwargs:
            return grid
        else:
            # Render grid wrapped in panels
            return trans.fill_template( "workflow/list_published.mako", grid=grid )
                                    
    @web.expose
    def display_by_username_and_slug( self, trans, username, slug ):
        """ Display workflow based on a username and slug. """ 
        
        # Get workflow.
        session = trans.sa_session
        user = session.query( model.User ).filter_by( username=username ).first()
        stored_workflow = trans.sa_session.query( model.StoredWorkflow ).filter_by( user=user, slug=slug, deleted=False ).first()
        if stored_workflow is None:
           raise web.httpexceptions.HTTPNotFound()
        # Security check raises error if user cannot access workflow.
        self.security_check( trans.get_user(), stored_workflow, False, True)
        
        # Get data for workflow's steps.
        self.get_stored_workflow_steps( trans, stored_workflow )
        # Get annotations.
        stored_workflow.annotation = self.get_item_annotation_str( trans, stored_workflow.user, stored_workflow )
        for step in stored_workflow.latest_workflow.steps:
            step.annotation = self.get_item_annotation_str( trans, stored_workflow.user, step )

        # Get rating data.
        user_item_rating = 0
        if trans.get_user():
            user_item_rating = self.get_user_item_rating( trans, trans.get_user(), stored_workflow )
            if user_item_rating:
                user_item_rating = user_item_rating.rating
            else:
                user_item_rating = 0
        ave_item_rating, num_ratings = self.get_ave_item_rating_data( trans, stored_workflow )            
        return trans.fill_template_mako( "workflow/display.mako", item=stored_workflow, item_data=stored_workflow.latest_workflow.steps,
                                            user_item_rating = user_item_rating, ave_item_rating=ave_item_rating, num_ratings=num_ratings )

    @web.expose
    def get_item_content_async( self, trans, id ):
        """ Returns item content in HTML format. """
        
        stored = self.get_stored_workflow( trans, id, False, True )
        if stored is None:
            raise web.httpexceptions.HTTPNotFound()
            
        # Get data for workflow's steps.
        self.get_stored_workflow_steps( trans, stored )
        # Get annotations.
        stored.annotation = self.get_item_annotation_str( trans, stored.user, stored )
        for step in stored.latest_workflow.steps:
            step.annotation = self.get_item_annotation_str( trans, stored.user, step )
        return trans.stream_template_mako( "/workflow/item_content.mako", item = stored, item_data = stored.latest_workflow.steps )
                              
    @web.expose
    @web.require_login( "use Galaxy workflows" )
    def share( self, trans, id, email="" ):
        msg = mtype = None
        # Load workflow from database
        stored = self.get_stored_workflow( trans, id )
        if email:
            other = trans.sa_session.query( model.User ) \
                                    .filter( and_( model.User.table.c.email==email,
                                                   model.User.table.c.deleted==False ) ) \
                                    .first()
            if not other:
                mtype = "error"
                msg = ( "User '%s' does not exist" % email )
            elif other == trans.get_user():
                mtype = "error"
                msg = ( "You cannot share a workflow with yourself" )
            elif trans.sa_session.query( model.StoredWorkflowUserShareAssociation ) \
                    .filter_by( user=other, stored_workflow=stored ).count() > 0:
                mtype = "error"
                msg = ( "Workflow already shared with '%s'" % email )
            else:
                share = model.StoredWorkflowUserShareAssociation()
                share.stored_workflow = stored
                share.user = other
                session = trans.sa_session
                session.add( share )
                self.create_item_slug( session, stored )
                session.flush()
                trans.set_message( "Workflow '%s' shared with user '%s'" % ( stored.name, other.email ) )
                return trans.response.send_redirect( url_for( controller='workflow', action='sharing', id=id ) )
        return trans.fill_template( "workflow/share.mako",
                                    message = msg,
                                    messagetype = mtype,
                                    stored=stored,
                                    email=email )
    
    @web.expose
    @web.require_login( "use Galaxy workflows" )
    def sharing( self, trans, id, **kwargs ):
        """ Handle workflow sharing. """
        
        # Get session and workflow.
        session = trans.sa_session
        stored = self.get_stored_workflow( trans, id )
        session.add( stored )
        
        # Do operation on workflow.
        if 'make_accessible_via_link' in kwargs:
            self._make_item_accessible( trans.sa_session, stored )
        elif 'make_accessible_and_publish' in kwargs:
            self._make_item_accessible( trans.sa_session, stored )
            stored.published = True
        elif 'publish' in kwargs:
            stored.published = True
        elif 'disable_link_access' in kwargs:
            stored.importable = False
        elif 'unpublish' in kwargs:
            stored.published = False
        elif 'disable_link_access_and_unpublish' in kwargs:
            stored.importable = stored.published = False
        elif 'unshare_user' in kwargs:
            user = session.query( model.User ).get( trans.security.decode_id( kwargs['unshare_user' ] ) )
            if not user:
                error( "User not found for provided id" )
            association = session.query( model.StoredWorkflowUserShareAssociation ) \
                                 .filter_by( user=user, stored_workflow=stored ).one()
            session.delete( association )
            
        # Legacy issue: workflows made accessible before recent updates may not have a slug. Create slug for any workflows that need them.
        if stored.importable and not stored.slug:
            self._make_item_accessible( trans.sa_session, stored )
            
        session.flush()
        
        return trans.fill_template( "/sharing_base.mako",
                                    item=stored )

    @web.expose
    @web.require_login( "to import a workflow", use_panels=True )
    def imp( self, trans, id, **kwargs ):
        # Set referer message.
        referer = trans.request.referer
        if referer is not "":
            referer_message = "<a href='%s'>return to the previous page</a>" % referer
        else:
            referer_message = "<a href='%s'>go to Galaxy's start page</a>" % url_for( '/' )
                    
        # Do import.
        session = trans.sa_session
        stored = self.get_stored_workflow( trans, id, check_ownership=False )
        if stored.importable == False:
            return trans.show_error_message( "The owner of this workflow has disabled imports via this link.<br>You can %s" % referer_message, use_panels=True )
        elif stored.user == trans.user:
            return trans.show_error_message( "You can't import this workflow because you own it.<br>You can %s" % referer_message, use_panels=True )
        elif stored.deleted:
            return trans.show_error_message( "You can't import this workflow because it has been deleted.<br>You can %s" % referer_message, use_panels=True )
        else:
            # Create imported workflow via copy.
            imported_stored = model.StoredWorkflow()
            imported_stored.name = "imported: " + stored.name
            imported_stored.latest_workflow = stored.latest_workflow
            imported_stored.user = trans.user
            # Save new workflow.
            session = trans.sa_session
            session.add( imported_stored )
            session.flush()
            
            # Redirect to load galaxy frames.
            return trans.show_ok_message(
                message="""Workflow "%s" has been imported. <br>You can <a href="%s">start using this workflow</a> or %s.""" 
                % ( stored.name, web.url_for( controller='workflow' ), referer_message ), use_panels=True )
            
    @web.expose
    @web.require_login( "use Galaxy workflows" )
    def edit_attributes( self, trans, id, **kwargs ):
        # Get workflow and do error checking.
        stored = self.get_stored_workflow( trans, id )
        if not stored:
            error( "You do not own this workflow or workflow ID is invalid." )
            
        # Update workflow attributes if new values submitted.
        if 'name' in kwargs:
            # Rename workflow.
            stored.name = kwargs[ 'name' ]
        if 'annotation' in kwargs:
            # Set workflow annotation; sanitize annotation before adding it.
            annotation = sanitize_html( kwargs[ 'annotation' ], 'utf-8', 'text/html' )
            self.add_item_annotation( trans, stored,  annotation )
        trans.sa_session.flush()
        
        return trans.fill_template( 'workflow/edit_attributes.mako', 
                                    stored=stored, 
                                    annotation=self.get_item_annotation_str( trans, trans.user, stored ) 
                                    )
    
    @web.expose
    @web.require_login( "use Galaxy workflows" )
    def rename( self, trans, id, new_name=None, **kwargs ):
        stored = self.get_stored_workflow( trans, id )
        if new_name is not None:
            stored.name = new_name
            trans.sa_session.flush()
            # For current workflows grid:
            trans.set_message ( "Workflow renamed to '%s'." % new_name )
            return self.list( trans )
            # For new workflows grid:
            #message = "Workflow renamed to '%s'." % new_name
            #return self.list_grid( trans, message=message, status='done' )
        else:
            return form( url_for( action='rename', id=trans.security.encode_id(stored.id) ), "Rename workflow", submit_text="Rename" ) \
                .add_text( "new_name", "Workflow Name", value=stored.name )
                
    @web.expose
    @web.require_login( "use Galaxy workflows" )
    def rename_async( self, trans, id, new_name=None, **kwargs ):
        stored = self.get_stored_workflow( trans, id )
        if new_name:
            stored.name = new_name
            trans.sa_session.flush()
            return stored.name
            
    @web.expose
    @web.require_login( "use Galaxy workflows" )
    def annotate_async( self, trans, id, new_annotation=None, **kwargs ):
        stored = self.get_stored_workflow( trans, id )
        if new_annotation:
            # Sanitize annotation before adding it.
            new_annotation = sanitize_html( new_annotation, 'utf-8', 'text/html' )
            self.add_item_annotation( trans, stored, new_annotation )
            trans.sa_session.flush()
            return new_annotation
            
    @web.expose
    @web.require_login( "rate items" )
    @web.json
    def rate_async( self, trans, id, rating ):
        """ Rate a workflow asynchronously and return updated community data. """

        stored = self.get_stored_workflow( trans, id, check_ownership=False, check_accessible=True )
        if not stored:
            return trans.show_error_message( "The specified workflow does not exist." )

        # Rate workflow.
        stored_rating = self.rate_item( trans, trans.get_user(), stored, rating )

        return self.get_ave_item_rating_data( trans, stored )
            
    @web.expose
    @web.require_login( "use Galaxy workflows" )
    def set_accessible_async( self, trans, id=None, accessible=False ):
        """ Set workflow's importable attribute and slug. """
        stored = self.get_stored_workflow( trans, id )

        # Only set if importable value would change; this prevents a change in the update_time unless attribute really changed.
        importable = accessible in ['True', 'true', 't', 'T'];
        if stored and stored.importable != importable:
            if importable:
                self._make_item_accessible( trans.sa_session, stored )
            else:
                stored.importable = importable
            trans.sa_session.flush()
        return
        
    @web.expose
    @web.require_login( "modify Galaxy items" )
    def set_slug_async( self, trans, id, new_slug ):
        stored = self.get_stored_workflow( trans, id )
        if stored:
            stored.slug = new_slug
            trans.sa_session.flush()
            return stored.slug
            
    @web.expose
    def get_embed_html_async( self, trans, id ):
        """ Returns HTML for embedding a workflow in a page. """

        # TODO: user should be able to embed any item he has access to. see display_by_username_and_slug for security code.
        stored = self.get_stored_workflow( trans, id )
        if stored:
            return "Embedded Workflow '%s'" % stored.name
        
    @web.expose
    @web.json
    @web.require_login( "use Galaxy workflows" )
    def get_name_and_link_async( self, trans, id=None ):
        """ Returns workflow's name and link. """
        stored = self.get_stored_workflow( trans, id )

        if self.create_item_slug( trans.sa_session, stored ):
            trans.sa_session.flush()
        return_dict = { "name" : stored.name, "link" : url_for( action="display_by_username_and_slug", username=stored.user.username, slug=stored.slug ) }
        return return_dict
    
    @web.expose
    @web.require_login( "use Galaxy workflows" )
    def clone( self, trans, id ):
        stored = self.get_stored_workflow( trans, id, check_ownership=False )
        user = trans.get_user()
        if stored.user == user:
            owner = True
        else:
            if trans.sa_session.query( model.StoredWorkflowUserShareAssociation ) \
                    .filter_by( user=user, stored_workflow=stored ).count() == 0:
                error( "Workflow is not owned by or shared with current user" )
            owner = False
        new_stored = model.StoredWorkflow()
        new_stored.name = "Clone of '%s'" % stored.name
        new_stored.latest_workflow = stored.latest_workflow
        if not owner:
            new_stored.name += " shared by '%s'" % stored.user.email
        new_stored.user = user
        # Persist
        session = trans.sa_session
        session.add( new_stored )
        session.flush()
        # Display the management page
        trans.set_message( 'Clone created with name "%s"' % new_stored.name )
        return self.list( trans )
    
    @web.expose
    @web.require_login( "create workflows" )
    def create( self, trans, workflow_name=None, workflow_annotation="" ):
        """
        Create a new stored workflow with name `workflow_name`.
        """
        user = trans.get_user()
        if workflow_name is not None:
            # Create the new stored workflow
            stored_workflow = model.StoredWorkflow()
            stored_workflow.name = workflow_name
            stored_workflow.user = user
            # And the first (empty) workflow revision
            workflow = model.Workflow()
            workflow.name = workflow_name
            workflow.stored_workflow = stored_workflow
            stored_workflow.latest_workflow = workflow
            # Add annotation.
            workflow_annotation = sanitize_html( workflow_annotation, 'utf-8', 'text/html' )
            self.add_item_annotation( trans, stored_workflow, workflow_annotation )
            # Persist
            session = trans.sa_session
            session.add( stored_workflow )
            session.flush()
            # Display the management page
            trans.set_message( "Workflow '%s' created" % stored_workflow.name )
            return self.list( trans )
        else:
            return form( url_for(), "Create New Workflow", submit_text="Create" ) \
                    .add_text( "workflow_name", "Workflow Name", value="Unnamed workflow" ) \
                    .add_text( "workflow_annotation", "Workflow Annotation", value="", help="A description of the workflow; annotation is shown alongside shared or published workflows." )
    
    @web.expose
    def delete( self, trans, id=None ):
        """
        Mark a workflow as deleted
        """        
        # Load workflow from database
        stored = self.get_stored_workflow( trans, id )
        # Marke as deleted and save
        stored.deleted = True
        trans.sa_session.add( stored )
        trans.sa_session.flush()
        # Display the management page
        trans.set_message( "Workflow '%s' deleted" % stored.name )
        return self.list( trans )
        
    @web.expose
    @web.require_login( "edit workflows" )
    def editor( self, trans, id=None ):
        """
        Render the main workflow editor interface. The canvas is embedded as
        an iframe (necessary for scrolling to work properly), which is
        rendered by `editor_canvas`.
        """
        if not id:
            error( "Invalid workflow id" )
        stored = self.get_stored_workflow( trans, id )
        return trans.fill_template( "workflow/editor.mako", stored=stored, annotation=self.get_item_annotation_str( trans, trans.user, stored ) )
        
    @web.json
    def editor_form_post( self, trans, type='tool', tool_id=None, annotation=None, **incoming ):
        """
        Accepts a tool state and incoming values, and generates a new tool
        form and some additional information, packed into a json dictionary.
        This is used for the form shown in the right pane when a node
        is selected.
        """
        
        trans.workflow_building_mode = True
        module = module_factory.from_dict( trans, {
            'type': type,
            'tool_id': tool_id,
            'tool_state': incoming.pop("tool_state")
        } )
        module.update_state( incoming )
        
        if type=='tool':
            return {
                'tool_state': module.get_state(),
                'data_inputs': module.get_data_inputs(),
                'data_outputs': module.get_data_outputs(),
                'tool_errors': module.get_errors(),
                'form_html': module.get_config_form(),
                'annotation': annotation,
                'post_job_actions': module.get_post_job_actions()
            }
        else:
            return {
                'tool_state': module.get_state(),
                'data_inputs': module.get_data_inputs(),
                'data_outputs': module.get_data_outputs(),
                'tool_errors': module.get_errors(),
                'form_html': module.get_config_form(),
                'annotation': annotation
            }
        
    @web.json
    def get_new_module_info( self, trans, type, **kwargs ):
        """
        Get the info for a new instance of a module initialized with default
        parameters (any keyword arguments will be passed along to the module).
        Result includes data inputs and outputs, html representation
        of the initial form, and the initial tool state (with default values).
        This is called asynchronously whenever a new node is added.
        """
        trans.workflow_building_mode = True
        module = module_factory.new( trans, type, **kwargs )
        return {
            'type': module.type,
            'name':  module.get_name(),
            'tool_id': module.get_tool_id(),
            'tool_state': module.get_state(),
            'tooltip': module.get_tooltip(),
            'data_inputs': module.get_data_inputs(),
            'data_outputs': module.get_data_outputs(),
            'form_html': module.get_config_form(),
            'annotation': ""
        }

    @web.json
    def load_workflow( self, trans, id ):
        """
        Get the latest Workflow for the StoredWorkflow identified by `id` and
        encode it as a json string that can be read by the workflow editor
        web interface.
        """
        user = trans.get_user()
        id = trans.security.decode_id( id )
        trans.workflow_building_mode = True
        # Load encoded workflow from database
        stored = trans.sa_session.query( model.StoredWorkflow ).get( id )
        assert stored.user == user
        workflow = stored.latest_workflow
        # Pack workflow data into a dictionary and return
        data = {}
        data['name'] = workflow.name
        data['steps'] = {}
        data['upgrade_messages'] = {}
        # For each step, rebuild the form and encode the state
        for step in workflow.steps:
            # Load from database representation
            module = module_factory.from_workflow_step( trans, step )
            # Fix any missing parameters
            upgrade_message = module.check_and_update_state()
            if upgrade_message:
                # FIXME: Frontend should be able to handle workflow messages
                #        as a dictionary not just the values
                data['upgrade_messages'][step.order_index] = upgrade_message.values()
            # Get user annotation.
            step_annotation = self.get_item_annotation_obj ( trans, trans.user, step )
            annotation_str = ""
            if step_annotation:
                annotation_str = step_annotation.annotation
            # Pack attributes into plain dictionary
            step_dict = {
                'id': step.order_index,
                'type': module.type,
                'tool_id': module.get_tool_id(),
                'name': module.get_name(),
                'tool_state': module.get_state(),
                'tooltip': module.get_tooltip(),
                'tool_errors': module.get_errors(),
                'data_inputs': module.get_data_inputs(),
                'data_outputs': module.get_data_outputs(),
                'form_html': module.get_config_form(),
                'annotation' : annotation_str
            }
            # Connections
            input_connections = step.input_connections
            if step.type is None or step.type == 'tool':
                # Determine full (prefixed) names of valid input datasets
                data_input_names = {}
                def callback( input, value, prefixed_name, prefixed_label ):
                    if isinstance( input, DataToolParameter ):
                        data_input_names[ prefixed_name ] = True
                visit_input_values( module.tool.inputs, module.state.inputs, callback )
                # Filter
                # FIXME: this removes connection without displaying a message currently!
                input_connections = [ conn for conn in input_connections if conn.input_name in data_input_names ]
                # post_job_actions
                pja_dict = {}
                for pja in step.post_job_actions:
                    pja_dict[pja.action_type+pja.output_name] = dict(action_type = pja.action_type, 
                                            output_name = pja.output_name,
                                            action_arguments = pja.action_arguments)
                step_dict['post_job_actions'] = pja_dict
            # Encode input connections as dictionary
            input_conn_dict = {}
            for conn in input_connections:
                input_conn_dict[ conn.input_name ] = \
                    dict( id=conn.output_step.order_index, output_name=conn.output_name )
            step_dict['input_connections'] = input_conn_dict
            # Position
            step_dict['position'] = step.position
            # Add to return value
            data['steps'][step.order_index] = step_dict
        return data

    @web.json
    def save_workflow( self, trans, id, workflow_data ):
        """
        Save the workflow described by `workflow_data` with id `id`.
        """
        # Get the stored workflow
        stored = self.get_stored_workflow( trans, id )
        # Put parameters in workflow mode
        trans.workflow_building_mode = True
        # Convert incoming workflow data from json
        data = simplejson.loads( workflow_data )
        # Create new workflow from incoming data
        workflow = model.Workflow()
        # Just keep the last name (user can rename later)
        workflow.name = stored.name
        # Assume no errors until we find a step that has some
        workflow.has_errors = False
        # Create each step
        steps = []
        # The editor will provide ids for each step that we don't need to save,
        # but do need to use to make connections
        steps_by_external_id = {}
        # First pass to build step objects and populate basic values
        for key, step_dict in data['steps'].iteritems():
            # Create the model class for the step
            step = model.WorkflowStep()
            steps.append( step )
            steps_by_external_id[ step_dict['id' ] ] = step
            # FIXME: Position should be handled inside module
            step.position = step_dict['position']
            module = module_factory.from_dict( trans, step_dict )
            module.save_to_step( step )
            if step.tool_errors:
                workflow.has_errors = True
            # Stick this in the step temporarily
            step.temp_input_connections = step_dict['input_connections']
            # Save step annotation.
            annotation = step_dict[ 'annotation' ]
            if annotation:
                annotation = sanitize_html( annotation, 'utf-8', 'text/html' )
                self.add_item_annotation( trans, step, annotation )
        # Second pass to deal with connections between steps
        for step in steps:
            # Input connections
            for input_name, conn_dict in step.temp_input_connections.iteritems():
                if conn_dict:
                    conn = model.WorkflowStepConnection()
                    conn.input_step = step
                    conn.input_name = input_name
                    conn.output_name = conn_dict['output_name']
                    conn.output_step = steps_by_external_id[ conn_dict['id'] ]
            del step.temp_input_connections
        # Order the steps if possible
        attach_ordered_steps( workflow, steps )
        # Connect up
        workflow.stored_workflow = stored
        stored.latest_workflow = workflow
        # Persist
        trans.sa_session.flush()
        # Return something informative
        errors = []
        if workflow.has_errors:
            errors.append( "Some steps in this workflow have validation errors" )
        if workflow.has_cycles:
            errors.append( "This workflow contains cycles" )
        if errors:
            rval = dict( message="Workflow saved, but will not be runnable due to the following errors",
                         errors=errors )
        else:
            rval = dict( message="Workflow saved" )
        rval['name'] = workflow.name
        return rval

    @web.json_pretty
    def export_workflow( self, trans, id ):
        """
        Get the latest Workflow for the StoredWorkflow identified by `id` and
        encode it as a json string that can be imported back into Galaxy
        
        This has slightly different information than the above. In particular,
        it does not attempt to decode forms and build UIs, it just stores
        the raw state.
        """
        user = trans.get_user()
        id = trans.security.decode_id( id )
        trans.workflow_building_mode = True
        # Load encoded workflow from database
        stored = trans.sa_session.query( model.StoredWorkflow ).get( id )
        self.security_check( trans.get_user(), stored, False, True )
        workflow = stored.latest_workflow
        # Pack workflow data into a dictionary and return
        data = {}
        data['name'] = workflow.name
        data['steps'] = {}
        # For each step, rebuild the form and encode the state
        for step in workflow.steps:
            # Load from database representation
            module = module_factory.from_workflow_step( trans, step )
            # Get user annotation.
            step_annotation = self.get_item_annotation_obj( trans, trans.user, step )
            annotation_str = ""
            if step_annotation:
                annotation_str = step_annotation.annotation
            # Pack attributes into plain dictionary
            step_dict = {
                'id': step.order_index,
                'type': module.type,
                'tool_id': module.get_tool_id(),
                'name': module.get_name(),
                'tool_state': module.get_state( secure=False ),
                'tool_errors': module.get_errors(),
                ## 'data_inputs': module.get_data_inputs(),
                ## 'data_outputs': module.get_data_outputs(),
                'annotation' : annotation_str
            }
            # Connections
            input_connections = step.input_connections
            if step.type is None or step.type == 'tool':
                # Determine full (prefixed) names of valid input datasets
                data_input_names = {}
                def callback( input, value, prefixed_name, prefixed_label ):
                    if isinstance( input, DataToolParameter ):
                        data_input_names[ prefixed_name ] = True
                visit_input_values( module.tool.inputs, module.state.inputs, callback )
                # Filter
                # FIXME: this removes connection without displaying a message currently!
                input_connections = [ conn for conn in input_connections if conn.input_name in data_input_names ]
            # Encode input connections as dictionary
            input_conn_dict = {}
            for conn in input_connections:
                input_conn_dict[ conn.input_name ] = \
                    dict( id=conn.output_step.order_index, output_name=conn.output_name )
            step_dict['input_connections'] = input_conn_dict
            # Position
            step_dict['position'] = step.position
            # Add to return value
            data['steps'][step.order_index] = step_dict
        return data

    @web.expose
    def import_workflow( self, trans, workflow_text=None, url=None ):
        if workflow_text is None and url is None:
            return form( url_for(), "Import Workflow", submit_text="Import" ) \
                    .add_text( "url", "URL to load workflow from", "" ) \
                    .add_input( "textarea", "Encoded workflow (as generated by export workflow)", "workflow_text", "" )
        if url:
            # Load workflow from external URL
            # NOTE: blocks the web thread. 
            try:
                workflow_data = urllib2.urlopen( url ).read()
            except Exception, e:
                return trans.show_error_message( "Failed to open URL %s<br><br>Message: %s" % ( url, str( e ) ) )
        else:
            workflow_data = workflow_text
        # Convert incoming workflow data from json
        try:
            data = simplejson.loads( workflow_data )
        except Exception, e:
            return trans.show_error_message( "Data at '%s' does not appear to be a Galaxy workflow<br><br>Message: %s" % ( url, str( e ) ) )
        # Put parameters in workflow mode
        trans.workflow_building_mode = True
        # Create new workflow from incoming data
        workflow = model.Workflow()
        # Just keep the last name (user can rename later)
        workflow.name = data['name']
        # Assume no errors until we find a step that has some
        workflow.has_errors = False
        # Create each step
        steps = []
        # The editor will provide ids for each step that we don't need to save,
        # but do need to use to make connections
        steps_by_external_id = {}
        # First pass to build step objects and populate basic values
        for key, step_dict in data['steps'].iteritems():
            # Create the model class for the step
            step = model.WorkflowStep()
            steps.append( step )
            steps_by_external_id[ step_dict['id' ] ] = step
            # FIXME: Position should be handled inside module
            step.position = step_dict['position']
            module = module_factory.from_dict( trans, step_dict, secure=False )
            module.save_to_step( step )
            if step.tool_errors:
                workflow.has_errors = True
            # Stick this in the step temporarily
            step.temp_input_connections = step_dict['input_connections']
            # Save step annotation.
            annotation = step_dict[ 'annotation' ]
            if annotation:
                annotation = sanitize_html( annotation, 'utf-8', 'text/html' )
                self.add_item_annotation( trans, step, annotation )
        # Second pass to deal with connections between steps
        for step in steps:
            # Input connections
            for input_name, conn_dict in step.temp_input_connections.iteritems():
                if conn_dict:
                    conn = model.WorkflowStepConnection()
                    conn.input_step = step
                    conn.input_name = input_name
                    conn.output_name = conn_dict['output_name']
                    conn.output_step = steps_by_external_id[ conn_dict['id'] ]
            del step.temp_input_connections
        # Order the steps if possible
        attach_ordered_steps( workflow, steps )
        # Connect up
        stored = model.StoredWorkflow()
        stored.name = workflow.name
        workflow.stored_workflow = stored
        stored.latest_workflow = workflow
        stored.user = trans.user
        # Persist
        trans.sa_session.add( stored )
        trans.sa_session.flush()
        # Return something informative
        errors = []
        if workflow.has_errors:
            return trans.show_warn_message( "Imported, but some steps in this workflow have validation errors" )
        if workflow.has_cycles:
            return trans.show_warn_message( "Imported, but this workflow contains cycles" )
        else:
            return trans.show_message( "Workflow '%s' imported" % workflow.name )
        
    @web.json
    def get_datatypes( self, trans ):
        ext_to_class_name = dict()
        classes = []
        for k, v in trans.app.datatypes_registry.datatypes_by_extension.iteritems():
            c = v.__class__
            ext_to_class_name[k] = c.__module__ + "." + c.__name__
            classes.append( c )
        class_to_classes = dict()
        def visit_bases( types, cls ):
            for base in cls.__bases__:
                if issubclass( base, Data ):
                    types.add( base.__module__ + "." + base.__name__ )
                visit_bases( types, base )
        for c in classes:      
            n =  c.__module__ + "." + c.__name__
            types = set( [ n ] )
            visit_bases( types, c )
            class_to_classes[ n ] = dict( ( t, True ) for t in types )
        return dict( ext_to_class_name=ext_to_class_name, class_to_classes=class_to_classes )
    
    @web.expose
    def build_from_current_history( self, trans, job_ids=None, dataset_ids=None, workflow_name=None ):
        user = trans.get_user()
        history = trans.get_history()
        if not user:
            return trans.show_error_message( "Must be logged in to create workflows" )
        if ( job_ids is None and dataset_ids is None ) or workflow_name is None:
            jobs, warnings = get_job_dict( trans )
            # Render
            return trans.fill_template(
                        "workflow/build_from_current_history.mako", 
                        jobs=jobs,
                        warnings=warnings,
                        history=history )
        else:
            # Ensure job_ids and dataset_ids are lists (possibly empty)
            if job_ids is None:
                job_ids = []
            elif type( job_ids ) is not list:
                job_ids = [ job_ids ]
            if dataset_ids is None:
                dataset_ids = []
            elif type( dataset_ids ) is not list:
                dataset_ids = [ dataset_ids ]
            # Convert both sets of ids to integers
            job_ids = [ int( id ) for id in job_ids ]
            dataset_ids = [ int( id ) for id in dataset_ids ]
            # Find each job, for security we (implicately) check that they are
            # associated witha job in the current history. 
            jobs, warnings = get_job_dict( trans )
            jobs_by_id = dict( ( job.id, job ) for job in jobs.keys() )
            steps = []
            steps_by_job_id = {}
            hid_to_output_pair = {}
            # Input dataset steps
            for hid in dataset_ids:
                step = model.WorkflowStep()
                step.type = 'data_input'
                hid_to_output_pair[ hid ] = ( step, 'output' )
                steps.append( step )
            # Tool steps
            for job_id in job_ids:
                assert job_id in jobs_by_id, "Attempt to create workflow with job not connected to current history"
                job = jobs_by_id[ job_id ]
                tool = trans.app.toolbox.tools_by_id[ job.tool_id ]
                param_values = job.get_param_values( trans.app )
                associations = cleanup_param_values( tool.inputs, param_values )
                step = model.WorkflowStep()
                step.type = 'tool'
                step.tool_id = job.tool_id
                step.tool_inputs = tool.params_to_strings( param_values, trans.app )
                # NOTE: We shouldn't need to do two passes here since only
                #       an earlier job can be used as an input to a later
                #       job.
                for other_hid, input_name in associations:
                    if other_hid in hid_to_output_pair:
                        other_step, other_name = hid_to_output_pair[ other_hid ]
                        conn = model.WorkflowStepConnection()
                        conn.input_step = step
                        conn.input_name = input_name
                        # Should always be connected to an earlier step
                        conn.output_step = other_step
                        conn.output_name = other_name
                steps.append( step )
                steps_by_job_id[ job_id ] = step                
                # Store created dataset hids
                for assoc in job.output_datasets:
                    hid_to_output_pair[ assoc.dataset.hid ] = ( step, assoc.name )
            # Workflow to populate
            workflow = model.Workflow()
            workflow.name = workflow_name
            # Order the steps if possible
            attach_ordered_steps( workflow, steps )
            # And let's try to set up some reasonable locations on the canvas
            # (these are pretty arbitrary values)
            levorder = order_workflow_steps_with_levels( steps )
            base_pos = 10
            for i, steps_at_level in enumerate( levorder ):
                for j, index in enumerate( steps_at_level ):
                    step = steps[ index ]
                    step.position = dict( top = ( base_pos + 120 * j ),
                                          left = ( base_pos + 220 * i ) )
            # Store it
            stored = model.StoredWorkflow()
            stored.user = user
            stored.name = workflow_name
            workflow.stored_workflow = stored
            stored.latest_workflow = workflow
            trans.sa_session.add( stored )
            trans.sa_session.flush()
            # Index page with message
            return trans.show_message( "Workflow '%s' created from current history." % workflow_name )
            ## return trans.show_ok_message( "<p>Workflow '%s' created.</p><p><a target='_top' href='%s'>Click to load in workflow editor</a></p>"
            ##     % ( workflow_name, web.url_for( action='editor', id=trans.security.encode_id(stored.id) ) ) )       
        
    @web.expose
    def run( self, trans, id, check_user=True, **kwargs ):
        stored = self.get_stored_workflow( trans, id, check_ownership=False )
        if check_user:
            user = trans.get_user()
            if stored.user != user:
                if trans.sa_session.query( model.StoredWorkflowUserShareAssociation ) \
                        .filter_by( user=user, stored_workflow=stored ).count() == 0:
                    error( "Workflow is not owned by or shared with current user" )
        # Get the latest revision
        workflow = stored.latest_workflow
        # It is possible for a workflow to have 0 steps
        if len( workflow.steps ) == 0:
            error( "Workflow cannot be run because it does not have any steps" )
        #workflow = Workflow.from_simple( simplejson.loads( stored.encoded_value ), trans.app )
        if workflow.has_cycles:
            error( "Workflow cannot be run because it contains cycles" )
        if workflow.has_errors:
            error( "Workflow cannot be run because of validation errors in some steps" )
        # Build the state for each step
        errors = {}
        has_upgrade_messages = False
        has_errors = False
        if kwargs:
            # If kwargs were provided, the states for each step should have
            # been POSTed
            for step in workflow.steps:
                step.upgrade_messages = {}
                # Connections by input name
                step.input_connections_by_name = \
                    dict( ( conn.input_name, conn ) for conn in step.input_connections ) 
                # Extract just the arguments for this step by prefix
                p = "%s|" % step.id
                l = len(p)…