# ------------------------------------------------------------------------------
#
#  Copyright (c) 2008, 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:   01/10/2006
#
# ------------------------------------------------------------------------------

""" Defines the array editor factory for all traits toolkit backends.
"""



import numpy

from traits.api import Bool, HasTraits, Int, Float, Instance, TraitError

from ..editor import Editor

from ..editor_factory import EditorFactory

# CIRCULAR IMPORT FIXME: Importing from the source rather than traits.ui.api
# to avoid circular imports, as this EditorFactory will be part of
# traits.ui.api as well.
from ..view import View

from ..group import Group

from ..item import Item

# -------------------------------------------------------------------------
#  'ToolkitEditorFactory' class:
# -------------------------------------------------------------------------


class ToolkitEditorFactory(EditorFactory):
    """ Editor factory for array editors.
    """

    # -------------------------------------------------------------------------
    #  Trait definitions:
    # -------------------------------------------------------------------------

    #: Width of the individual fields
    width = Int(-80)

    #: Is user input set on every keystroke?
    auto_set = Bool(True)

    #: Is user input set when the Enter key is pressed?
    enter_set = Bool(False)


class ArrayStructure(HasTraits):

    # -------------------------------------------------------------------------
    #  Trait definitions:
    # -------------------------------------------------------------------------

    #: Editor that this structure is linked to
    editor = Instance(Editor)

    #: The constructed View for the array
    view = Instance(View)

    def __init__(self, editor):
        """ Initializes the object.
        """
        # Save the reference to the editor:
        self.editor = editor

        # Set up the field width for each item:
        width = editor.factory.width

        # Set up the correct style for each filed:
        style = "simple"
        if editor.readonly:
            style = "readonly"

        # Get the array we are mirroring:
        object = editor.value

        # Determine the correct trait type to use for each element:
        trait = Float()

        if object.dtype.type == "i":
            trait = Int()

        if len(object.shape) == 1:
            self.view = self._one_dim_view(object, style, width, trait)
        elif len(object.shape) == 2:
            self.view = self._two_dim_view(object, style, width, trait)
        else:
            raise TraitError("Only 1D or 2D arrays supported")

    # -------------------------------------------------------------------------
    #  1D view:
    # -------------------------------------------------------------------------

    def _one_dim_view(self, object, style, width, trait):
        content = []
        shape = object.shape
        items = []
        format_func = self.editor.factory.format_func
        format_str = self.editor.factory.format_str
        for i in range(shape[0]):
            name = "f%d" % i
            self.add_trait(
                name,
                trait(
                    object[i],
                    event="field",
                    auto_set=self.editor.factory.auto_set,
                    enter_set=self.editor.factory.enter_set,
                ),
            )
            items.append(
                Item(
                    name=name,
                    style=style,
                    width=width,
                    format_func=format_func,
                    format_str=format_str,
                    padding=-3,
                )
            )

        group = Group(orientation="horizontal", show_labels=False, *items)
        content.append(group)

        return View(Group(show_labels=False, *content))

    # -------------------------------------------------------------------------
    #  2D view:
    # -------------------------------------------------------------------------

    def _two_dim_view(self, object, style, width, trait):
        content = []
        shape = object.shape
        format_func = self.editor.factory.format_func
        format_str = self.editor.factory.format_str
        for i in range(shape[0]):
            items = []
            for j in range(shape[1]):
                name = "f%d_%d" % (i, j)
                self.add_trait(
                    name,
                    trait(
                        object[i, j],
                        event="field",
                        auto_set=self.editor.factory.auto_set,
                        enter_set=self.editor.factory.enter_set,
                    ),
                )
                items.append(
                    Item(
                        name=name,
                        style=style,
                        width=width,
                        format_func=format_func,
                        format_str=format_str,
                        padding=-3,
                    )
                )

            group = Group(orientation="horizontal", show_labels=False, *items)
            content.append(group)

        return View(Group(show_labels=False, *content))

    def _field_changed(self):
        """ Updates the underlying array when any field changes value.
        """

        if not self.editor._busy:
            # Get the array we are mirroring:
            object = self.editor.value
            shape = object.shape
            value = numpy.zeros(shape, object.dtype)

            # 1D
            if len(shape) == 1:
                for i in range(shape[0]):
                    value[i] = getattr(self, "f%d" % i)
            # 2D
            elif len(shape) == 2:
                for i in range(shape[0]):
                    for j in range(shape[1]):
                        value[i, j] = getattr(self, "f%d_%d" % (i, j))

            self.editor.update_array(value)


# -------------------------------------------------------------------------
#  Toolkit-independent 'SimpleEditor' class:
# -------------------------------------------------------------------------


class SimpleEditor(Editor):
    """ Simple style of editor for arrays.
    """

    # -------------------------------------------------------------------------
    #  Trait definitions:
    # -------------------------------------------------------------------------

    # Is the editor read-only?
    readonly = Bool(False)

    def init(self, parent):
        """ Finishes initializing the editor by creating the underlying toolkit
            widget.
        """
        self._as = _as = ArrayStructure(self)
        ui = _as.view.ui(_as, parent, kind="subpanel")
        ui.parent = self.ui
        self.control = ui.control

    def update_editor(self):
        """ Updates the editor when the object trait changes externally to the
            editor.
        """

        if not self._busy:
            self._busy = True
            object = self.value
            shape = object.shape
            _as = self._as

            # 1D
            if len(shape) == 1:
                for i in range(shape[0]):
                    setattr(_as, "f%d" % i, object[i])
            # 2D
            elif len(shape) == 2:
                for i in range(shape[0]):
                    for j in range(shape[1]):
                        setattr(_as, "f%d_%d" % (i, j), object[i, j])

            self._busy = False

    def update_array(self, value):
        """ Updates the array value associated with the editor.
        """
        self._busy = True
        self.value = value
        self._busy = False


# Define the ArrayEditor class
ArrayEditor = ToolkitEditorFactory
