# Source code for tecplot.layout.layout

    import fnmatch
    import logging
    import re
    import warnings

    from os import path

    from ..tecutil import _tecutil
    from ..constant import *
    from ..exception import *
    from .. import session, tecutil
    from ..tecutil import sv
    from .page import Page

    log = logging.getLogger(__name__)

    @tecutil.lock()
    def new_layout():
        """Clears the current layout and creates a blank frame.

        This will invalidate any object instances previously obtained:

        .. code-block:: python
            :emphasize-lines: 4

            import tecplot

            frame = tecplot.active_frame()
            tecplot.new_layout()

            # frame object is no longer usable.
            # the following will print:
            #       <class 'ValueError'> 255 is not a valid PlotType
            try:
                frame.plot_type
            except Exception as e:
                print(type(e),e)
        """
        _tecutil.NewLayout()

    @tecutil.lock()
    def load_layout(filename):
        """Reads a layout file and replaces the active frame.

        Parameters:
            filename (`str`): The file name of the layout to be loaded.
                (See note below conerning absolute and relative paths.)

        Raises:
            `TecplotOSError`: If file can not be found.
            `TecplotSystemError`: If the file could not be loaded.

        .. note:: **Absolute and relative paths with PyTecplot**

            Relative paths, when used within the PyTecplot API are always from
            Python's current working directory which can be obtained by calling
            :func:`os.getcwd()`. This is true for batch and `connected
            <tecplot.session.connect()>` modes. One exception to this is paths
            within a macro command or file which will be relative to the |Tecplot
            Engine|'s home directory, which is typically the |Tecplot 360|
            installation directory. Finally, when connected to a remote (non-local)
            instance of Tecplot 360, only absolute paths are allowed.

            Note that backslashes must be escaped which is especially important for
            windows paths such as ``"C:\\\\Users"`` or ``"\\\\\\\\server\\\\path"``
            which will resolve to ``"C:\\Users"`` and ``"\\\\server\\path"``
            respectively. Alternatively, one may use Python's raw strings:
            ``r"C:\\Users"`` and ``r"\\\\server\\path"``

        This will replace the current layout and therefore will invalidate any
        object instances previously obtained:

        .. code-block:: python
            :emphasize-lines: 8

            import os
            import tecplot as tp

            frame = tp.active_frame()

            examples = tp.session.tecplot_examples_directory()
            layoutfile = os.path.join(examples, 'SimpleData', 'F18.lay')
            tp.load_layout(layoutfile)

            # frame object is no longer usable.
            # the following will print:
            #       <class 'ValueError'> 255 is not a valid PlotType
            try:
                frame.plot_type
            except Exception as e:
                print(type(e),e)
        """
        filepath = tecutil.normalize_path(filename)
        with tecutil.ArgList(FNAME=filepath) as arglist:
            if not _tecutil.OpenLayoutX(arglist):
                raise TecplotSystemError(filepath)

    @tecutil.lock()
    def save_layout(filename, include_data=None, include_preview=None,
                    use_relative_paths=None, post_layout_commands=None,
                    pages=None):
        """Writes the current layout to a file.

        Parameters:
            filename (`str`): The path to the output filename. (See note
                below conerning absolute and relative paths.)
            include_data (`bool`, optional): Associated value indicates
                if the layout should be saved as a layout package where the data
                is included with the style information or if it should reference
                linked data. If 'include_data' is None and the filename ends
                with '.lpk', then the file will be saved as a layout package file.
                (default: None)
            include_preview (`bool`, optional): Associated value
                indicates if the layout package should also include a preview
                image. This argument only applies if the include data option is
                True. (default: `True`)
            use_relative_paths (`bool`, optional): Associated value
                indicates if the layout should be saved using relative paths.
                This argument only applies if the include data option is `False`.
                (default: `False`)
            post_layout_commands (`str`, optional): A character string
                containing a set of Tecplot macro commands that are appended to
                the layout or layout package file. These can be almost anything
                and are generally used to store add-on specific state
                information using ``$!EXTENDEDCOMMAND`` commands. (default:
                `None`)
            pages (`list` of `Page <layout.Page>` objects, optional): If `None`, all pages
                are written to the layout, otherwise the specified subset of pages
                are written. (default: `None`)

        .. note:: **Absolute and relative paths with PyTecplot**

            Relative paths, when used within the PyTecplot API are always from
            Python's current working directory which can be obtained by calling
            :func:`os.getcwd()`. This is true for batch and `connected
            <tecplot.session.connect()>` modes. One exception to this is paths
            within a macro command or file which will be relative to the |Tecplot
            Engine|'s home directory, which is typically the |Tecplot 360|
            installation directory. Finally, when connected to a remote (non-local)
            instance of Tecplot 360, only absolute paths are allowed.

            Note that backslashes must be escaped which is especially important for
            windows paths such as ``"C:\\\\Users"`` or ``"\\\\\\\\server\\\\path"``
            which will resolve to ``"C:\\Users"`` and ``"\\\\server\\path"``
            respectively. Alternatively, one may use Python's raw strings:
            ``r"C:\\Users"`` and ``r"\\\\server\\path"``

        .. note::

            If you receive an exception with the error message "Journal should be
            valid in all frames", then you must save a data file using
            `save_tecplot_ascii` or `save_tecplot_plt` before saving the layout.

        In this example, we load an example layout file and then save it as a
        packaged layout file:

        .. code-block:: python
            :emphasize-lines: 8

            import os
            import tecplot

            examples_dir = tecplot.session.tecplot_examples_directory()
            infile = os.path.join(examples_dir, 'SimpleData', 'F18.lay')

            tecplot.load_layout(infile)
            tecplot.save_layout('output.lpk')
        """
        if include_data is None and filename.lower().endswith('.lpk'):
            include_data = True

        with tecutil.ArgList() as arglist:
            arglist[sv.FNAME] = tecutil.normalize_path(filename)

            for arg, svarg in [(include_data, sv.INCLUDEDATA),
                               (include_preview, sv.INCLUDEPREVIEW),
                               (use_relative_paths, sv.USERELATIVEPATHS),
                               (post_layout_commands, sv.POSTLAYOUTCOMMANDS)]:
                if arg is not None:
                    arglist[svarg] = arg

            if pages is not None:
                # Allow either an int array or page object array
                if isinstance(pages[0], int):
                    arglist[sv.PAGELIST] = tecutil.IndexSet(P for P in pages)
                else:
                    arglist[sv.PAGELIST] = tecutil.IndexSet(P.position
                                                            for P in pages)

            if not _tecutil.SaveLayoutX(arglist):
                raise TecplotSystemError()

    def active_page():
        """Returns the currently active page.

        Returns:
            `Page <layout.Page>`: The currently active page.

        Only one `Page <layout.Page>` can be active at any given time. As long as the page is not
        deleted (through a call to `new_layout` or `load_layout` for example) this
        can be used to bring it back to the active state:

        .. code-block:: python
            :emphasize-lines: 3

            import tecplot

            page1 = tecplot.active_page()
            page2 = tecplot.add_page()

            # page2 is now active
            assert page2.active

            # we can bring page1 back to the front:
            page1.activate()
            assert page1.active
        """
        return Page(_tecutil.PageGetUniqueID())

    def num_pages():
        """Returns the number of pages in the layout.

        Returns: `int`

        Example usage::

            >>> print(tecplot.layout.num_pages())
            1
        """
        return _tecutil.PageGetCount()

    @tecutil.lock()
    def add_page():
        """Adds a `Page <layout.Page>` to the layout.

        Returns:
            `Page <layout.Page>`: The newly created page.

        This will implicitly activate the newly created page:

        .. code-block:: python
            :emphasize-lines: 3

            import tecplot
            page1 = tecplot.active_page()
            page2 = tecplot.add_page()
            # page2 is now active
            assert page2.active
        """
        if _tecutil.PageCreateNew():
            return Page(_tecutil.PageGetUniqueID())
        else:
            raise TecplotSystemError('could not add-create-new page')

    @tecutil.lock()
    def delete_page(page_to_delete):
        """Removes a `Page <layout.Page>` from the layout.

        This will render any `Page <layout.Page>` object pointing to the deleted `Page <layout.Page>` useless.
        The unique ID will not be used again in the active session and it is up
        to the user to clear the python object using `del`:

        .. code-block:: python
            :emphasize-lines: 5

            import tecplot as tp
            from tecplot.exception import TecplotRuntimeError

            page = tp.add_page()
            tp.delete_page(page)

            next_page = tp.active_page()

            assert page != next_page
            assert not page.active

            try:
                # the page is gone so activating
                # will produce an exception
                page.activate()
            except TecplotRuntimeError as e:
                print(e)

            del page # clear the python object
        """
        page_to_delete.activate()
        _tecutil.PageDelete()

    @tecutil.lock()
    def next_page():
        """Activates and returns the next page.

        Returns:
            `layout.Page`: The next page in the layout.

        `Page <layout.Page>` objects are stored in an ordered stack in the |Tecplot Engine|. This
        method rotates the stack and returns the resulting active `Page <layout.Page>`:

        .. code-block:: python
            :emphasize-lines: 6

            import tecplot
            from tecplot.layout import next_page

            page1 = tecplot.active_page()
            page2 = tecplot.add_page()
            page3 = next_page()

            # page1 is now the active page
            # and is the same as page3
            assert page1.active
            assert page3 == page1
        """
        _tecutil.PageSetCurrentToNext()
        return active_page()

    def page(pattern):
        """Returns the page by name.

        Parameters:
            pattern (`str` or `re.Pattern <re.compile>`): Case-insensitive
                `glob-style pattern string <fnmatch.fnmatch>` or a compiled
                `regex pattern instance <re.compile>` used to match the page by
                name.

        Returns:
            `Page <layout.Page>`: The first page identified by *pattern*.

        .. note::

            A layout can contain `pages <tecplot.layout.Page>` with identical names and only the
            first match found is returned. This is not guaranteed to be
            deterministic and care should be taken to have only `pages <tecplot.layout.Page>` with
            unique names when this feature is used.

        Example:

        .. code-block:: python
            :emphasize-lines: 6

            import tecplot
            page11 = tecplot.add_page()
            page11.name = 'Page 11'
            page12 = tecplot.add_page()
            page12.name = 'Page 12'
            assert page12 == tecplot.page('Page 1*')
        """
        return next(pages(pattern), None)

    def pages(pattern=None):
        """Yields pages matching a specified pattern.

        Parameters:
            pattern (`str` or `re.Pattern <re.compile>`, optional):
                Case-insensitive `glob-style pattern string <fnmatch.fnmatch>` or a
                compiled `regex pattern instance <re.compile>` used to match page
                names.

        Returns:
            `Page <layout.Page>`: Generator of pages identified by *pattern* or all pages if
            no *pattern* is specified.

        This function returns a generator which can only be iterated over once.
        It can be converted to a `list` for persistence:

        .. code-block:: python

            import tecplot

            # iterate over all frames in
            # all pages and print their names
            for page in tecplot.pages():
                for frame in page.frames():
                    print(frame.name)

            # store a persistent list of pages
            pages = list(tecplot.pages())
        """
        if pattern:
            pattern_type = getattr(re, 'Pattern', getattr(re, '_pattern_type', None))
            if not isinstance(pattern, pattern_type):
                regex = re.compile(fnmatch.translate(pattern), re.IGNORECASE)
            else:
                regex = pattern

        if __debug__:
            found = False
        for i in range(num_pages()):
            current_page = Page(_tecutil.PageGetUniqueID())
            if pattern is None or regex.match(current_page.name):
                if __debug__:
                    found = True
                yield current_page
            next_page()

        if __debug__:
            if (
                not found and
                pattern is not None and
                isinstance(pattern, str) and
                any(c in pattern for c in '*?[]')
            ):
                msg = 'no pages found matching: "{}"'.format(pattern)
                warning = TecplotPatternMatchWarning(pattern, msg, 'glob')
                warnings.warn(warning)

    def active_frame():
        """Returns the active frame.

        Returns:
            `Frame <layout.Frame>`: Currently active frame.
        """
        return active_page().active_frame()

    def frames(frame_pattern=None, page_pattern=None):
        """Returns a generator of frames matching the specified pattern.

        Parameters:
            frame_pattern (`str` or `re.Pattern <re.compile>`): Case-insensitive
                `glob-style pattern string <fnmatch.fnmatch>` or a compiled
                `regex pattern instance <re.compile>` used to match the frame by
                name. All frames are returned if no pattern is specified.
            page_pattern (`str` or `re.Pattern <re.compile>`): Case-insensitive
                `glob-style pattern string <fnmatch.fnmatch>` or a compiled
                `regex pattern instance <re.compile>` used to match the page by
                name. All pages are included if no pattern is specified.

        Returns:
            `Frame <layout.Frame>`: Generator of frames identified by name patterns.

        .. code-block:: python

            import tecplot

            # print name of all frames on all pages
            for frame in tecplot.frames():
                print(frame.name)
        """
        for page in pages(page_pattern):
            for frame in page.frames(frame_pattern):
                yield frame

    def aux_data():
        """Auxiliary data for the current layout.

        Returns:
            `AuxData`

        This is the auxiliary data attached to the entire layout containing all
        frames and datasets currently held by the Tecplot Engine. Such data is
        written to the layout file by default and can be retrieved later. Example
        usage:

        .. code-block:: python

            import tecplot as tp

            aux = tp.layout.aux_data()
            aux['info'] = '''\
            This layout contains a lot of things:
                1. Something
                2. Something else
                3. Also this'''

            '''
            The following will print (including newlines):
                This layout contains a lot of things:
                    1. Something
                    2. Something else
                    3. Also this
            '''
            print(aux['info'])
        """
        return session.AuxData(None, AuxDataObjectType.Layout)