# -------------------------------------------------------------------------
#
#  Copyright (c) 2007, Enthought, Inc.
#  All rights reserved.
#
#  This software is provided without warranty under the terms of the BSD
#  license included in LICENSE.txt and may be redistributed only
#  under the conditions described in the aforementioned license.  The license
#  is also available online at http://www.enthought.com/licenses/BSD.txt
#
#  Thanks for using Enthought open source!
#
#  Author: David C. Morrill
#  Date:   08/29/2007

# -------------------------------------------------------------------------

""" Defines an ArrayViewEditor for displaying 1-d or 2-d arrays of values.
"""

# -- Imports --------------------------------------------------------------


from traits.api import Instance, Property, List, Str, Bool

from ..api import View, Item, TabularEditor, BasicEditorFactory
from ..tabular_adapter import TabularAdapter
from ..toolkit import toolkit_object
from ..toolkit_traits import Font
from ..ui_editor import UIEditor

# -- Tabular Adapter Definition -------------------------------------------


class ArrayViewAdapter(TabularAdapter):

    #: Is the array 1D or 2D?
    is_2d = Bool(True)

    #: Should array rows and columns be transposed:
    transpose = Bool(False)

    alignment = "right"
    index_text = Property()

    def _get_index_text(self):
        return str(self.row)

    def _get_content(self):
        if self.is_2d:
            return self.item[self.column_id]

        return self.item

    def get_item(self, object, trait, row):
        """ Returns the value of the *object.trait[row]* item.
        """
        if self.is_2d:
            if self.transpose:
                return getattr(object, trait)[:, row]

            return super(ArrayViewAdapter, self).get_item(object, trait, row)

        return getattr(object, trait)[row]

    def len(self, object, trait):
        """ Returns the number of items in the specified *object.trait* list.
        """
        if self.transpose:
            return getattr(object, trait).shape[1]

        return super(ArrayViewAdapter, self).len(object, trait)


# Define the actual abstract Traits UI array view editor (each backend should
# implement its own editor that inherits from this class.


class _ArrayViewEditor(UIEditor):

    #: Indicate that the editor is scrollable/resizable:
    scrollable = True

    #: Should column titles be displayed:
    show_titles = Bool(False)

    #: The tabular adapter being used for the editor view:
    adapter = Instance(ArrayViewAdapter)

    # -- Private Methods ------------------------------------------------------

    def _array_view(self):
        """ Return the view used by the editor.
        """
        return View(
            Item(
                "object.object." + self.name,
                id="tabular_editor",
                show_label=False,
                editor=TabularEditor(
                    show_titles=self.show_titles,
                    editable=False,
                    adapter=self.adapter,
                ),
            ),
            id="array_view_editor",
            resizable=True,
        )

    def init_ui(self, parent):
        """ Creates the Traits UI for displaying the array.
        """
        # Make sure that the value is an array of the correct shape:
        shape = self.value.shape
        len_shape = len(shape)
        if (len_shape == 0) or (len_shape > 2):
            raise ValueError(
                "ArrayViewEditor can only display 1D or 2D " "arrays"
            )

        factory = self.factory
        cols = 1
        titles = factory.titles
        n = len(titles)
        self.show_titles = n > 0
        is_2d = len_shape == 2
        if is_2d:
            index = 1
            if factory.transpose:
                index = 0
            cols = shape[index]
            if self.show_titles:
                if n > cols:
                    titles = titles[:cols]
                elif n < cols:
                    if (cols % n) == 0:
                        titles, old_titles, i = [], titles, 0
                        while len(titles) < cols:
                            titles.extend(
                                "%s%d" % (title, i) for title in old_titles
                            )
                            i += 1
                    else:
                        titles.extend([""] * (cols - n))
            else:
                titles = ["Data %d" % i for i in range(cols)]

        columns = [(title, i) for i, title in enumerate(titles)]

        if factory.show_index:
            columns.insert(0, ("Index", "index"))

        self.adapter = ArrayViewAdapter(
            is_2d=is_2d,
            columns=columns,
            transpose=factory.transpose,
            format=factory.format,
            font=factory.font,
        )

        return self.edit_traits(
            view="_array_view", parent=parent, kind="subpanel"
        )


# Define the ArrayViewEditor class used by client code:


class ArrayViewEditor(BasicEditorFactory):

    #: The editor implementation class:
    klass = Property()

    #: Should an index column be displayed:
    show_index = Bool(True)

    #: List of (optional) column titles:
    titles = List(Str)

    #: Should the array be logically transposed:
    transpose = Bool(False)

    #: The format used to display each array element:
    format = Str("%s")

    #: The font to use for displaying each array element:
    font = Font("Courier 10")

    def _get_klass(self):
        """ The class used to construct editor objects.
        """
        return toolkit_object("array_view_editor:_ArrayViewEditor")
