# Copyright (c) 2009-2020 - Simon Conseil
# Copyright (c)      2014 - Jamie Starke

# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to
# deal in the Software without restriction, including without limitation the
# rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
# sell copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:

# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.

# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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# IN THE SOFTWARE.

"""Plugin which generates HTML pages for each image.

Currently this plugin can be used only with the colorbox theme, the other
themes have to be adapted.

For themes, the ``previous_media`` and ``next_media`` variables contain the
previous/next :class:`~sigal.gallery.Media` objects.

"""

import os

from sigal import signals
from sigal.utils import url_from_path
from sigal.writer import AbstractWriter


class PageWriter(AbstractWriter):
    """A writer for writing media pages, based on writer"""

    template_file = "media.html"

    def write(self, album, media_group):
        """Generate the media page and save it"""

        from sigal import __url__ as sigal_link

        ctx = {
            "album": album,
            "media": media_group[0],
            "previous_media": media_group[-1],
            "next_media": media_group[1],
            "index_title": self.index_title,
            "settings": self.settings,
            "sigal_link": sigal_link,
            "theme": {
                "name": os.path.basename(self.theme),
                "url": url_from_path(os.path.relpath(self.theme_path, album.dst_path)),
            },
        }
        page = self.template.render(ctx)

        file_path = os.path.join(album.dst_path, media_group[0].dst_filename)
        output_file = f"{file_path}.html"

        with open(output_file, "w", encoding="utf-8") as f:
            f.write(page)


def generate_media_pages(gallery):
    """Generates and writes the media pages for all media in the gallery"""

    writer = PageWriter(gallery.settings, index_title=gallery.title)

    for album in gallery.albums.values():
        medias = album.medias
        next_medias = medias[1:] + [None]
        previous_medias = [None] + medias[:-1]

        # The media group allows us to easily get next and previous links
        media_groups = zip(medias, next_medias, previous_medias)

        for media_group in media_groups:
            writer.write(album, media_group)


def register(settings):
    signals.gallery_build.connect(generate_media_pages)
