import os
import scipy
import gobject
import gtk
import fluents
import logger, dataset, plots, main

class Project:
    """A Project contains datasets, selections etc.
    The project, of which the application has only one at any given time,
    is the container for all datasets, plots and selections in use. The data
    in the project is organized in a gtk.TreeStrore that is displayed in the
    navigator.
    """

    def __init__(self, name="Testing"):
        self.data_tree = gtk.TreeStore(str,
                                       str,
                                       object, 
                                       str,
                                       str,
                                       gobject.TYPE_OBJECT, 
                                       float)

        self.name = name
        self.dim_names = []
        self._selection_observers = []
        self._dataset_observers = []
        self.current_data = []
        self.datasets = []
        self.sel_obj = dataset.Selection('Current Selection')
        self.selections = []
        self._last_selection = None
        self._dataset_iter_map = {}
        
    def add_selection_observer(self, observer):
        self._selection_observers.append(observer)
        observer.selection_changed(None, self.get_selection())

    def notify_selection_listeners(self, dim_name):
        """Notifies observers"""
        for observer in self._selection_observers:
            observer.selection_changed(dim_name, self.get_selection())

    def add_dataset_observer(self, observer):
        self._dataset_observers.append(observer)
        observer.dataset_changed()

    def notify_dataset_listeners(self):
        """Notifies observers when new datasets are added"""
        for observer in self._dataset_observers:
            observer.dataset_changed()
        
    def set_selection(self, dim_name, selection):
        """Sets a current selection and notify observers"""
        self.sel_obj[dim_name] = set(selection)
        self.notify_selection_listeners(dim_name)
        self._last_selection = selection

    def get_selection(self):
        """Returns the current selection object"""
        return self.sel_obj

    def delete_data(self, it):
        """Delete elements from the project."""
        child = self.data_tree.iter_children(it)
        while child != None:
            c = self.data_tree.iter_next(child)
            self.delete_data(child)
            child = c
        main.application.main_view.remove_view(self.data_tree.get(it, 2)[0])
        self.data_tree.remove(it)

    def add_data(self, parents, data, fun='Function'):
        """Adds a set of data and plots to the navigator.

        This method is usually called after a Function in a workflow
        has finished and returns its output."""
        
        if len(parents) > 0: 
            parent_iter = self._dataset_iter_map[parents[0]]
        else:
            parent_iter = None

        # Add the function node to the tree
        icon = fluents.icon_factory.get("folder_grey")
        it = self.data_tree_insert(parent_iter, fun, None, None, "black", icon)
        
        # Add all returned datasets/plots/selections
        for d in data:
            # Any kind of dataset
            if isinstance(d, dataset.Dataset):
                if isinstance(d, dataset.GraphDataset):
                    icon = fluents.icon_factory.get("graph_dataset")
                elif isinstance(d, dataset.CategoryDataset):
                    icon = fluents.icon_factory.get("category_dataset")
                else:
                    icon = fluents.icon_factory.get("dataset")

                self.add_dataset(d)
                self.data_tree_insert(it, d.get_name(), d, None, "black", icon) 

            # Any kind of plot
            elif isinstance(d, plots.Plot):
                icon = fluents.icon_factory.get("line_plot")
                self.data_tree_insert(it, d.get_title(), d, None, "black", icon)
                d.set_selection_listener(self.set_selection)
                self._selection_observers.append(d)

            # Selections are not added to the data tree
            elif isinstance(d, dataset.Selection):
                self.add_selection(d)

    def data_tree_insert(self, parent, text, data, bg, fg, icon, selected = 0):
        """Inserts data into the tree view.
        @param text: The title of the object.
        @param data: A dataset, plot or function object.
        @param bg: Background color.
        @param fg: Foreground (font) color.
        @param icon: Pixmap icon.
        """
        tree = self.data_tree
        it = tree.append(parent)
        tree[it] = [text, type(data), data, bg, fg, icon, selected]
        self._dataset_iter_map[data] = it
        return it

    def add_dataset(self, dataset):
        """Appends a new Dataset to the project."""
        logger.log('debug','Adding dataset: %s' %dataset.get_name())
        self.datasets.append(dataset)
        for dim_name in dataset.get_all_dims():
            if dim_name not in self.dim_names:
                self.dim_names.append(dim_name)
                self.sel_obj[dim_name] = set()
                self.notify_selection_listeners(dim_name)
        self.notify_dataset_listeners()

    def add_selection(self, selection):
        """Adds a new selection to the project."""
        self.selections.append(selection)
        self.notify_dataset_listeners()
        
    def object_at(self, path):
        """Returns the object at a given path in the tree."""
        it = self.get_iter(path)
        obj = self[it][2]
        if obj:
            obj.show()
        return obj

    def set_current_data(self, obj):
        self.current_data = obj