# encoding: utf-8

"""
Custom element classes for presentation-related XML elements.
"""

from __future__ import absolute_import, division, print_function, unicode_literals

from .simpletypes import ST_SlideId, ST_SlideSizeCoordinate, XsdString
from .xmlchemy import BaseOxmlElement, RequiredAttribute, ZeroOrOne, ZeroOrMore


class CT_Presentation(BaseOxmlElement):
    """
    ``<p:presentation>`` element, root of the Presentation part stored as
    ``/ppt/presentation.xml``.
    """

    sldMasterIdLst = ZeroOrOne(
        "p:sldMasterIdLst",
        successors=(
            "p:notesMasterIdLst",
            "p:handoutMasterIdLst",
            "p:sldIdLst",
            "p:sldSz",
            "p:notesSz",
        ),
    )
    sldIdLst = ZeroOrOne("p:sldIdLst", successors=("p:sldSz", "p:notesSz"))
    sldSz = ZeroOrOne("p:sldSz", successors=("p:notesSz",))


class CT_SlideId(BaseOxmlElement):
    """
    ``<p:sldId>`` element, direct child of <p:sldIdLst> that contains an rId
    reference to a slide in the presentation.
    """

    id = RequiredAttribute("id", ST_SlideId)
    rId = RequiredAttribute("r:id", XsdString)


class CT_SlideIdList(BaseOxmlElement):
    """
    ``<p:sldIdLst>`` element, direct child of <p:presentation> that contains
    a list of the slide parts in the presentation.
    """

    sldId = ZeroOrMore("p:sldId")

    def add_sldId(self, rId):
        """
        Return a reference to a newly created <p:sldId> child element having
        its r:id attribute set to *rId*.
        """
        return self._add_sldId(id=self._next_id, rId=rId)

    @property
    def _next_id(self):
        """
        Return the next available slide ID as an int. Valid slide IDs start
        at 256. The next integer value greater than the max value in use is
        chosen, which minimizes that chance of reusing the id of a deleted
        slide.
        """
        id_str_lst = self.xpath("./p:sldId/@id")
        return max([255] + [int(id_str) for id_str in id_str_lst]) + 1


class CT_SlideMasterIdList(BaseOxmlElement):
    """
    ``<p:sldMasterIdLst>`` element, child of ``<p:presentation>`` containing
    references to the slide masters that belong to the presentation.
    """

    sldMasterId = ZeroOrMore("p:sldMasterId")


class CT_SlideMasterIdListEntry(BaseOxmlElement):
    """
    ``<p:sldMasterId>`` element, child of ``<p:sldMasterIdLst>`` containing
    a reference to a slide master.
    """

    rId = RequiredAttribute("r:id", XsdString)


class CT_SlideSize(BaseOxmlElement):
    """
    ``<p:sldSz>`` element, direct child of <p:presentation> that contains the
    width and height of slides in the presentation.
    """

    cx = RequiredAttribute("cx", ST_SlideSizeCoordinate)
    cy = RequiredAttribute("cy", ST_SlideSizeCoordinate)