# Source code for sdl2.ext.bitmapfont

    from .. import surface, rect, pixels
    from .err import SDLError, raise_sdl_err
    from .sprite import SoftwareSprite
    from .surface import _get_target_surface
    from .image import load_bmp

    __all__ = ["BitmapFont"]

    class BitmapFont(object):
        """A class for rendering text using a given bitmap font.

        This class takes an image of equally-spaced font characters and a font map
        indicating the location of each character on the image, and uses these to
        render text using the given font. This class is based on base SDL2 functions
        and does not require the SDL_ttf library to be installed.

        The font mapping table is a list of strings, with each string representing
        a row of characters on the font image surface. Each character within each
        line is assumed to be of equal height and width, but this can be adjusted
        using the :meth:`remap` method.

        For example, the built-in bitmap font ``font.bmp`` has the following layout:

        .. image:: images/font.png

        The default font mapping table, which matches the layout of ``font.bmp``,
        looks like this::

           fontmap = [
               '0123456789',
               'ABCDEFGHIJ',
               'KLMNOPQRST',
               'UVWXYZ    ',
               'abcdefghij',
               'klmnopqrst',
               'uvwxyz    ',
               ',;.:!?+-()',
            ]

        Args:
            font_img (:obj:`SDL_Surface` or str): A surface or path to a file
                containing a valid bitmap (``.bmp``) font image.
            size (tuple, optional): A ``(width, height)`` tuple defining the size of
                each character in the bitmap font. If not specified, this will be
                inferred automatically from the fontmap and font image.
            fontmap (list, optional): A list of strings defining the locations of
                characters in the font image. If not specified, the default font map
                defined above will be used.

        """
        DEFAULTMAP = [
            "0123456789",
            "ABCDEFGHIJ",
            "KLMNOPQRST",
            "UVWXYZ    ",
            "abcdefghij",
            "klmnopqrst",
            "uvwxyz    ",
            ",;.:!?+-()",
        ]

        def __init__(self, font_img, size=None, mapping=None):
            if hasattr(font_img, "upper"):  # if string
                self.surface = load_bmp(font_img)
            elif isinstance(font_img, SoftwareSprite):
                self.surface = font_img.surface
                self._sprite = font_img  # prevent GC on the Sprite
            elif isinstance(font_img, surface.SDL_Surface):
                self.surface = font_img
            elif "SDL_Surface" in str(type(font_img)):
                self.surface = font_img.contents
            else:
                raise TypeError("font_img must be a Sprite or SDL_Surface")

            if mapping is None:
                self.mapping = list(BitmapFont.DEFAULTMAP)
            else:
                self.mapping = mapping

            if not size:
                map_rows = len(self.mapping)
                map_cols = len(self.mapping[0])
                surf_size = (float(self.surface.w), float(self.surface.h))
                size = (int(surf_size[0] / map_cols), int(surf_size[1] / map_rows))
            self.size = size[0], size[1]

            self.offsets = {}
            self._max_height = self.size[1]
            self._calculate_offsets()

        def _calculate_offsets(self):
            # Calculates the internal character offsets for each line
            self.offsets = {}
            x, y = 0, 0
            w, h = self.size
            for line in self.mapping:
                x = 0
                for c in line:
                    if c not in self.offsets.keys():
                        self.offsets[c] = rect.SDL_Rect(x, y, w, h)
                    x += w
                y += h

        def _validate_chars(self, text):
            e = "The character '{0}' does not exist within the current font mapping"
            for ch in text:
                if ch != "\n" and ch not in self.offsets.keys():
                    raise ValueError(e.format(ch))

        def _get_rendered_size(self, text, line_h):
            line_h = self._max_height if not line_h else line_h
            text_w, text_h = (0, 0)
            lines = text.split("\n")
            for line in lines:
                line_w = 0
                for c in line:
                    charsize = self.offsets[c]
                    line_w += charsize.w
                if line_w > text_w:
                    text_w = line_w
                text_h += line_h
            return (text_w, text_h)

        def _render_text(self, target, fontsf, lines, line_h, offset=(0, 0)):
            line_h = self._max_height if not line_h else line_h
            dstr = rect.SDL_Rect(0, 0, 0, 0)
            y = offset[1]
            for line in lines:
                x = offset[0]
                for c in line:
                    dstr.x = x
                    dstr.y = y + (line_h - self.offsets[c].h)
                    surface.SDL_BlitSurface(fontsf, self.offsets[c], target, dstr)
                    x += self.offsets[c].w
                y += line_h
            return (x, y)

        def remap(self, c, x, y, w, h):
            """Updates the source rectangle for a given font character.

            This method can be used to fine-tune the character mappings in the font
            image to produce better spacing in the rendered text.

            Args:
                c (str): The character to remap in the font image.
                x (int): The x coordinate (in pixels) of the top-left corner of the
                    new rectangle for the character.
                y (int): The y coordinate (in pixels) of the top-left corner of the
                    new rectangle for the character.
                w (int): The width (in pixels) of the new rectangle for the
                    character.
                h (int): The height (in pixels) of the new rectangle for the
                    character.

            """
            if len(c) > 1:
                raise ValueError("Can only remap one character at a time.")
            self._validate_chars(c)
            x, y, w, h = [int(i) for i in (x, y, w, h)]
            if any([w < 1, h < 1]):
                raise ValueError("Width and height must both be positive integers.")
            surf_w, surf_h = (self.surface.w, self.surface.h)
            if x < 0 or y < 0 or x+w >= surf_w or y+h >= surf_h:
                e = "Character rectangle cannot exceed the bounds of the font image"
                raise ValueError(e + " ({0}, {1}).".format(surf_w, surf_h))

            self.offsets[c] = rect.SDL_Rect(x, y, w, h)
            if h > self._max_height:
                self._max_height = h

        def render(self, text, bpp=None):
            # Deprecated: replaced by render_text, which returns a surface
            self._validate_chars(text)
            lines = text.split("\n")

            tw, th = self._get_rendered_size(text, None)
            if bpp is None:
                bpp = self.surface.format.contents.BitsPerPixel
            sf = surface.SDL_CreateRGBSurface(0, tw, th, bpp, 0, 0, 0, 0)
            if not sf:
                raise SDLError()
            imgsurface = SoftwareSprite(sf.contents, False)

            self._render_text(imgsurface.surface, self.surface, lines, None)
            return imgsurface

        def render_text(self, text, line_h=None, as_argb=True):
            """Renders a string of text to a new surface.

            If a newline character (``\\n``) is encountered in the string, it will
            be rendered as a line break in the rendered text.

            By default, this function also converts the rendered text from the native
            format of the font image to 32-bit ARGB, for consistency across functions
            and better compatibility with SDL2 renderers. To disable ARGB conversion,
            set the ``as_argb`` parameter to ``False``.

            Args:
                text (str): The string of text to render.
                line_h (int, optional): The line height (in pixels) to use for each
                    line of the rendered text. If not specified, the maximum
                    character height for the font will be used. Defaults to ``None``.
                as_argb (bool, optional): Whether the output surface should be
                    converted to 32-bit ARGB pixel format or left as-is. Defaults to
                    ``True`` (convert to ARGB).

            Returns:
                :obj:`~sdl2.SDL_Surface`: A surface containing the rendered text.

            Raises:
                ValueError: If a character in the text is not provided by the
                current font.

            """
            self._validate_chars(text)
            lines = text.split("\n")

            # Create a new surface with the same format as the font image
            tw, th = self._get_rendered_size(text, line_h)
            fmt = self.surface.format.contents.format
            bpp = 32  # according to SDL2 source, this has no effect
            sf = surface.SDL_CreateRGBSurfaceWithFormat(0, tw, th, bpp, fmt)
            if not sf:
                raise_sdl_err("creating the font surface")

            # Render text to the new surface, converting pixel format if necessary
            self._render_text(sf.contents, self.surface, lines, line_h)
            if as_argb and fmt != pixels.SDL_PIXELFORMAT_ARGB8888:
                out_fmt = pixels.SDL_AllocFormat(pixels.SDL_PIXELFORMAT_ARGB8888)
                sf_argb = surface.SDL_ConvertSurface(sf, out_fmt, 0)
                surface.SDL_FreeSurface(sf)
                sf = sf_argb
                if not sf:
                    raise_sdl_err("converting rendered text to ARGB format")

            return sf.contents

        def render_on(self, target, text, offset=(0, 0), line_h=None):
            """Renders a string of text to an existing surface.

            If a newline character (``\\n``) is encountered in the string, it will
            be rendered as a line break in the rendered text.

            Args:
                target (:obj:`~sdl2.SDL_Surface`): The surface on which to render
                    the given string.
                text (str): The string of text to render to the target surface.
                offset (tuple, optional): The ``(x, y)`` coordinates of the target
                    surface on which the top-left corner of the rendered text will
                    be placed. Defaults to ``(0, 0)``.
                line_h (int, optional): The line height (in pixels) to use for each
                    line of the rendered text. If not specified, the maximum
                    character height for the font will be used. Defaults to ``None``.

            Returns:
                tuple: The ``(x1, y1, x2, y2)`` rectangle of the target surface on
                which the text was rendered.

            Raises:
                ValueError: If a character in the text is not provided by the
                current font.

            """
            x1, y1 = offset
            dest = rect.SDL_Rect(x1, y1, 0, 0)
            target = _get_target_surface(target)

            sf = self.render_text(text, line_h, as_argb=False)
            ret = surface.SDL_BlitSurface(sf, None, target, dest)
            if ret != 0:
                raise_sdl_err("copying the text to the target surface")

            return (x1, y1, x1 + sf.w, y1 + sf.h)

        def contains(self, c):
            """Checks whether a given character is mapped within the font.

            Args:
                c (str): The character to check for within the font map.

            Returns:
                bool: ``True`` if the font contains the character, otherwise
                ``False``.

            """
            return c in self.offsets

        def can_render(self, text):
            # Deprecated: already throws informative exception on missing character
            lines = text.split("\n")
            for line in lines:
                for c in line:
                    if c != ' ' and c not in self.offsets:
                        return False
            return True