# -*- coding: utf-8 -*-

##########################################################################
# OpenLP - Open Source Lyrics Projection                                 #
# ---------------------------------------------------------------------- #
# Copyright (c) 2008-2022 OpenLP Developers                              #
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# This program is free software: you can redistribute it and/or modify   #
# it under the terms of the GNU General Public License as published by   #
# the Free Software Foundation, either version 3 of the License, or      #
# (at your option) any later version.                                    #
#                                                                        #
# This program is distributed in the hope that it will be useful,        #
# but WITHOUT ANY WARRANTY; without even the implied warranty of         #
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the          #
# GNU General Public License for more details.                           #
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# along with this program.  If not, see <https://www.gnu.org/licenses/>. #
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"""
This module is for controlling powerpoint. PPT API documentation:
`http://msdn.microsoft.com/en-us/library/aa269321(office.10).aspx`_
2010: https://msdn.microsoft.com/en-us/library/office/ff743835%28v=office.14%29.aspx
2013: https://msdn.microsoft.com/en-us/library/office/ff743835.aspx
"""
import logging

from openlp.core.common import trace_error_handler
from openlp.core.common.i18n import UiStrings
from openlp.core.common.platform import is_win
from openlp.core.common.registry import Registry
from openlp.core.display.screens import ScreenList
from openlp.core.lib.ui import critical_error_message_box, translate
from openlp.plugins.presentations.lib.presentationcontroller import PresentationController, PresentationDocument


if is_win():
    from win32com.client import Dispatch
    import win32con
    import win32gui
    import win32ui
    import winreg
    import pywintypes

log = logging.getLogger(__name__)


class PowerpointController(PresentationController):
    """
    Class to control interactions with PowerPoint Presentations. It creates the runtime Environment , Loads the and
    Closes the Presentation. As well as triggering the correct activities based on the users input.
    """
    log.info('PowerpointController loaded')

    def __init__(self, plugin):
        """
        Initialise the class
        """
        log.debug('Initialising')
        super(PowerpointController, self).__init__(plugin, 'Powerpoint', PowerpointDocument)
        self.supports = ['ppt', 'pps', 'pptx', 'ppsx', 'pptm']
        self.process = None

    def check_available(self):
        """
        PowerPoint is able to run on this machine.
        """
        log.debug('check_available')
        if is_win():
            try:
                winreg.OpenKey(winreg.HKEY_CLASSES_ROOT, 'PowerPoint.Application').Close()
                try:
                    # Try to detect if the version is 12 (2007) or above, and if so add 'odp' as a support filetype
                    version_key = winreg.OpenKey(winreg.HKEY_CLASSES_ROOT, 'PowerPoint.Application\\CurVer')
                    tmp1, app_version_string, tmp2 = winreg.EnumValue(version_key, 0)
                    version_key.Close()
                    app_version = int(app_version_string[-2:])
                    if app_version >= 12:
                        self.also_supports = ['odp']
                except (OSError, ValueError):
                    log.exception('Detection of powerpoint version using registry failed.')
                return True
            except OSError:
                pass
        return False

    if is_win():
        def start_process(self):
            """
            Loads PowerPoint process.
            """
            log.debug('start_process')
            if not self.process:
                self.process = Dispatch('PowerPoint.Application')

        def kill(self):
            """
            Called at system exit to clean up any running presentations.
            """
            log.debug('Kill powerpoint')
            while self.docs:
                self.docs[0].close_presentation()
            if self.process is None:
                return
            try:
                if self.process.Presentations.Count > 0:
                    return
                self.process.Quit()
            except (AttributeError, pywintypes.com_error):
                log.exception('Exception caught while killing powerpoint process')
                trace_error_handler(log)
            self.process = None


class PowerpointDocument(PresentationDocument):
    """
    Class which holds information and controls a single presentation.
    """

    def __init__(self, controller, document_path):
        """
        Constructor, store information about the file and initialise.

        :param controller:
        :param pathlib.Path document_path: Path to the document to load
        :rtype: None
        """
        log.debug('Init Presentation Powerpoint')
        super().__init__(controller, document_path)
        self.presentation = None
        self.index_map = {}
        self.slide_count = 0
        self.blank_slide = 1
        self.blank_click = None
        self.presentation_hwnd = None

    def load_presentation(self):
        """
        Called when a presentation is added to the SlideController. Opens the PowerPoint file using the process created
        earlier.
        """
        log.debug('load_presentation')
        try:
            if not self.controller.process:
                self.controller.start_process()
            self.presentation = self.controller.process.Presentations.Open(str(self.file_path), False, False, False)
            log.debug('Loaded presentation %s' % self.presentation.FullName)
            self.create_thumbnails()
            self.create_titles_and_notes()
            # Make sure powerpoint doesn't steal focus, unless we're on a single screen setup
            if len(ScreenList()) > 1:
                Registry().get('main_window').activateWindow()
            return True
        except (AttributeError, pywintypes.com_error):
            log.exception('Exception caught while loading Powerpoint presentation')
            trace_error_handler(log)
            return False

    def check_thumbnails(self):
        """
        This is an overwritten method of the method in the PresentationDocument class. It adds a check for content
        in self.index_map.

        :return: If the thumbnail is valid
        :rtype: bool
        """
        return super().check_thumbnails() and bool(self.index_map)

    def create_thumbnails(self):
        """
        Create the thumbnail images for the current presentation.

        Note an alternative and quicker method would be do::

            self.presentation.Slides[n].Copy()
            thumbnail = QApplication.clipboard.image()

        However, for the moment, we want a physical file since it makes life easier elsewhere.
        """
        log.debug('create_thumbnails')
        generate_thumbs = True
        if super().check_thumbnails():
            # No need for thumbnails but we still need the index
            generate_thumbs = False
        key = 1
        for num in range(self.presentation.Slides.Count):
            if not self.presentation.Slides(num + 1).SlideShowTransition.Hidden:
                self.index_map[key] = num + 1
                if generate_thumbs:
                    self.presentation.Slides(num + 1).Export(
                        str(self.get_thumbnail_folder() / 'slide{key:d}.png'.format(key=key)), 'png', 320, 240)
                key += 1
        self.slide_count = key - 1

    def close_presentation(self):
        """
        Close presentation and clean up objects. This is triggered by a new object being added to SlideController or
        OpenLP being shut down.
        """
        log.debug('close_presentation')
        if self.presentation:
            try:
                self.presentation.Close()
            except (AttributeError, pywintypes.com_error):
                log.exception('Caught exception while closing powerpoint presentation')
                trace_error_handler(log)
        self.presentation = None
        self.controller.remove_doc(self)
        # Make sure powerpoint doesn't steal focus, unless we're on a single screen setup
        if len(ScreenList()) > 1:
            Registry().get('main_window').activateWindow()

    def is_loaded(self):
        """
        Returns ``True`` if a presentation is loaded.
        """
        log.debug('is_loaded')
        try:
            if self.presentation is None or self.presentation.FullName != str(self.file_path):
                return False
        except (AttributeError, pywintypes.com_error):
            log.exception('Caught exception while in is_loaded')
            trace_error_handler(log)
            return False
        return True

    def is_active(self):
        """
        Returns ``True`` if a presentation is currently active.
        """
        log.debug('is_active')
        if not self.is_loaded():
            return False
        try:
            if self.presentation.SlideShowWindow is None:
                return False
            if self.presentation.SlideShowWindow.View is None:
                return False
        except (AttributeError, pywintypes.com_error):
            log.exception('Caught exception while in is_active')
            trace_error_handler(log)
            return False
        return True

    def unblank_screen(self):
        """
        Unblanks (restores) the presentation.
        """
        log.debug('unblank_screen')
        try:
            self.presentation.SlideShowWindow.Activate()
            self.presentation.SlideShowWindow.View.State = 1
            # Unblanking is broken in PowerPoint 2010 (14.0), need to redisplay
            if 15.0 > float(self.presentation.Application.Version) >= 14.0:
                self.presentation.SlideShowWindow.View.GotoSlide(self.index_map[self.blank_slide], False)
                if self.blank_click:
                    self.presentation.SlideShowWindow.View.GotoClick(self.blank_click)
        except (AttributeError, pywintypes.com_error):
            log.exception('Caught exception while in unblank_screen')
            trace_error_handler(log)
            self.show_error_msg()
        # Stop powerpoint from flashing in the taskbar
        if self.presentation_hwnd:
            win32gui.FlashWindowEx(self.presentation_hwnd, win32con.FLASHW_STOP, 0, 0)
        # Make sure powerpoint doesn't steal focus, unless we're on a single screen setup
        if len(ScreenList()) > 1:
            Registry().get('main_window').activateWindow()

    def blank_screen(self):
        """
        Blanks the screen.
        """
        log.debug('blank_screen')
        try:
            # Unblanking is broken in PowerPoint 2010 (14.0), need to save info for later
            if 15.0 > float(self.presentation.Application.Version) >= 14.0:
                self.blank_slide = self.get_slide_number()
                self.blank_click = self.presentation.SlideShowWindow.View.GetClickIndex()
            # ppSlideShowBlackScreen = 3
            self.presentation.SlideShowWindow.View.State = 3
        except (AttributeError, pywintypes.com_error):
            log.exception('Caught exception while in blank_screen')
            trace_error_handler(log)
            self.show_error_msg()

    def is_blank(self):
        """
        Returns ``True`` if screen is blank.
        """
        log.debug('is_blank')
        if self.is_active():
            try:
                # ppSlideShowBlackScreen = 3
                return self.presentation.SlideShowWindow.View.State == 3
            except (AttributeError, pywintypes.com_error):
                log.exception('Caught exception while in is_blank')
                trace_error_handler(log)
                self.show_error_msg()
        else:
            return False

    def stop_presentation(self):
        """
        Stops the current presentation and hides the output. Used when blanking to desktop.
        """
        log.debug('stop_presentation')
        try:
            self.presentation.SlideShowWindow.View.Exit()
        except (AttributeError, pywintypes.com_error):
            log.exception('Caught exception while in stop_presentation')
            trace_error_handler(log)
            self.show_error_msg()

    if is_win():
        def start_presentation(self):
            """
            Starts a presentation from the beginning.
            """
            log.debug('start_presentation')
            # SlideShowWindow measures its size/position by points, not pixels
            # https://technet.microsoft.com/en-us/library/dn528846.aspx
            try:
                dpi = win32ui.GetActiveWindow().GetDC().GetDeviceCaps(88)
            except win32ui.error:
                try:
                    dpi = win32ui.GetForegroundWindow().GetDC().GetDeviceCaps(88)
                except win32ui.error:
                    dpi = 96
            size = ScreenList().current.display_geometry
            ppt_window = None
            try:
                # Disable the presentation console
                self.presentation.SlideShowSettings.ShowPresenterView = 0
                # Start the presentation
                ppt_window = self.presentation.SlideShowSettings.Run()
            except (AttributeError, pywintypes.com_error):
                log.exception('Caught exception while in start_presentation')
                trace_error_handler(log)
                self.show_error_msg()
            if ppt_window and not Registry().get('settings').value('presentations/powerpoint control window'):
                try:
                    ppt_window.Top = size.y() * 72 / dpi
                    ppt_window.Height = size.height() * 72 / dpi
                    ppt_window.Left = size.x() * 72 / dpi
                    ppt_window.Width = size.width() * 72 / dpi
                except AttributeError:
                    log.exception('AttributeError while in start_presentation')
            # Find the presentation window and save the handle for later
            self.presentation_hwnd = None
            if ppt_window:
                log.debug('main display size:  y={y:d}, height={height:d}, '
                          'x={x:d}, width={width:d}'.format(y=size.y(), height=size.height(),
                                                            x=size.x(), width=size.width()))
                try:
                    win32gui.EnumWindows(self._window_enum_callback, size)
                except pywintypes.error:
                    # When _window_enum_callback returns False to stop the enumeration (looping over open windows)
                    # it causes an exception that is ignored here
                    pass
            # Make sure powerpoint doesn't steal focus, unless we're on a single screen setup
            if len(ScreenList()) > 1:
                Registry().get('main_window').activateWindow()

    def _window_enum_callback(self, hwnd, size):
        """
        Method for callback from win32gui.EnumWindows.
        Used to find the powerpoint presentation window and stop it flashing in the taskbar.
        """
        # Get the size of the current window and if it matches the size of our main display we assume
        # it is the powerpoint presentation window.
        (left, top, right, bottom) = win32gui.GetWindowRect(hwnd)
        window_title = win32gui.GetWindowText(hwnd)
        log.debug('window size:  left={left:d}, top={top:d}, '
                  'right={right:d}, bottom={bottom:d}'.format(left=left, top=top, right=right, bottom=bottom))
        log.debug('compare size:  {y:d} and {top:d}, {height:d} and {vertical:d}, '
                  '{x:d} and {left}, {width:d} and {horizontal:d}'.format(y=size.y(),
                                                                          top=top,
                                                                          height=size.height(),
                                                                          vertical=(bottom - top),
                                                                          x=size.x(),
                                                                          left=left,
                                                                          width=size.width(),
                                                                          horizontal=(right - left)))
        log.debug('window title: {title}'.format(title=window_title))
        if size.y() == top and size.height() == (bottom - top) and size.x() == left and \
                size.width() == (right - left) and self.file_path.stem in window_title:
            log.debug('Found a match and will save the handle')
            self.presentation_hwnd = hwnd
            # Stop powerpoint from flashing in the taskbar
            win32gui.FlashWindowEx(self.presentation_hwnd, win32con.FLASHW_STOP, 0, 0)
            # Returning false stops the enumeration (looping over open windows)
            return False
        else:
            return True

    def get_slide_number(self):
        """
        Returns the current slide number.
        """
        log.debug('get_slide_number')
        ret = 0
        try:
            # We need 2 approaches to getting the current slide number, because
            # SlideShowWindow.View.Slide.SlideIndex wont work on the end-slide where Slide isn't available, and
            # SlideShowWindow.View.CurrentShowPosition returns 0 when called when a transition is executing (in 2013)
            # So we use SlideShowWindow.View.Slide.SlideIndex unless the state is done (ppSlideShowDone = 5)
            if self.presentation.SlideShowWindow.View.State != 5:
                ret = self.presentation.SlideShowWindow.View.Slide.SlideIndex
                # Do reverse lookup in the index_map to find the slide number to return
                ret = next((key for key, slidenum in self.index_map.items() if slidenum == ret), None)
            else:
                ret = self.presentation.SlideShowWindow.View.CurrentShowPosition
        except (AttributeError, pywintypes.com_error):
            log.exception('Caught exception while in get_slide_number')
            trace_error_handler(log)
            self.show_error_msg()
        return ret

    def get_slide_count(self):
        """
        Returns total number of slides.
        """
        log.debug('get_slide_count')
        return self.slide_count

    def goto_slide(self, slide_no):
        """
        Moves to a specific slide in the presentation.

        :param slide_no: The slide the text is required for, starting at 1
        """
        log.debug('goto_slide')
        try:
            if Registry().get('settings').value('presentations/powerpoint slide click advance') \
                    and self.get_slide_number() == slide_no:
                click_index = self.presentation.SlideShowWindow.View.GetClickIndex()
                click_count = self.presentation.SlideShowWindow.View.GetClickCount()
                log.debug('We are already on this slide - go to next effect if any left, idx: '
                          '{index:d}, count: {count:d}'.format(index=click_index, count=click_count))
                if click_index < click_count:
                    self.next_step()
            else:
                self.presentation.SlideShowWindow.View.GotoSlide(self.index_map[slide_no])
        except (AttributeError, pywintypes.com_error):
            log.exception('Caught exception while in goto_slide')
            trace_error_handler(log)
            self.show_error_msg()

    def next_step(self):
        """
        Triggers the next effect of slide on the running presentation.
        """
        log.debug('next_step')
        # if we are at the presentations end don't go further, just return True
        if self.presentation.SlideShowWindow.View.GetClickCount() == \
                self.presentation.SlideShowWindow.View.GetClickIndex() \
                and self.get_slide_number() == self.get_slide_count():
            return True
        past_end = False
        try:
            self.presentation.SlideShowWindow.Activate()
            self.presentation.SlideShowWindow.View.Next()
        except (AttributeError, pywintypes.com_error):
            log.exception('Caught exception while in next_step')
            trace_error_handler(log)
            self.show_error_msg()
            return past_end
        # If for some reason the presentation end was not detected above, this will catch it.
        if self.get_slide_number() > self.get_slide_count():
            log.debug('past end, stepping back to previous')
            self.previous_step()
            past_end = True
        # Stop powerpoint from flashing in the taskbar
        if self.presentation_hwnd:
            win32gui.FlashWindowEx(self.presentation_hwnd, win32con.FLASHW_STOP, 0, 0)
        # Make sure powerpoint doesn't steal focus, unless we're on a single screen setup
        if len(ScreenList()) > 1:
            Registry().get('main_window').activateWindow()
        return past_end

    def previous_step(self):
        """
        Triggers the previous slide on the running presentation.
        """
        log.debug('previous_step')
        # if we are at the presentations start we can't go further back, just return True
        if self.presentation.SlideShowWindow.View.GetClickIndex() == 0 and self.get_slide_number() == 1:
            return True
        try:
            self.presentation.SlideShowWindow.View.Previous()
        except (AttributeError, pywintypes.com_error):
            log.exception('Caught exception while in previous_step')
            trace_error_handler(log)
            self.show_error_msg()
        return False

    def get_slide_text(self, slide_no):
        """
        Returns the text on the slide.

        :param slide_no: The slide the text is required for, starting at 1
        """
        return _get_text_from_shapes(self.presentation.Slides(self.index_map[slide_no]).Shapes)

    def get_slide_notes(self, slide_no):
        """
        Returns the text on the slide.

        :param slide_no: The slide the text is required for, starting at 1
        """
        return _get_text_from_shapes(self.presentation.Slides(self.index_map[slide_no]).NotesPage.Shapes)

    def create_titles_and_notes(self):
        """
        Writes the list of titles (one per slide)
        to 'titles.txt'
        and the notes to 'slideNotes[x].txt'
        in the thumbnails directory
        """
        titles = []
        notes = []
        for num in range(self.get_slide_count()):
            slide = self.presentation.Slides(self.index_map[num + 1])
            try:
                text = slide.Shapes.Title.TextFrame.TextRange.Text
            except Exception:
                log.exception('Exception raised when getting title text')
                text = ''
            slide_title = text.replace('\r\n', ' ').replace('\n', ' ').replace('\x0b', ' ').strip()
            titles.append(slide_title)
            note = _get_text_from_shapes(slide.NotesPage.Shapes)
            if len(note) == 0:
                note = ' '
            notes.append(note)
        self.save_titles_and_notes(titles, notes)

    def show_error_msg(self):
        """
        Stop presentation and display an error message.
        """
        try:
            self.presentation.SlideShowWindow.View.Exit()
        except (AttributeError, pywintypes.com_error):
            log.exception('Failed to exit Powerpoint presentation after error')
        critical_error_message_box(UiStrings().Error, translate('PresentationPlugin.PowerpointDocument',
                                                                'An error occurred in the PowerPoint integration '
                                                                'and the presentation will be stopped. '
                                                                'Restart the presentation if you wish to present it.'))


def _get_text_from_shapes(shapes):
    """
    Returns any text extracted from the shapes on a presentation slide.

    :param shapes: A set of shapes to search for text.
    """
    text = ''
    try:
        for shape in shapes:
            if shape.PlaceholderFormat.Type == 2:  # 2 from is enum PpPlaceholderType.ppPlaceholderBody
                if shape.HasTextFrame and shape.TextFrame.HasText:
                    text += shape.TextFrame.TextRange.Text + '\n'
    except pywintypes.com_error:
        log.exception('Failed to extract text from powerpoint slide')
    return text
