from __future__ import annotations

import re
from email.utils import parsedate_to_datetime
from io import BytesIO
from typing import Callable

import lxml.etree as etree
from scrapy.http import TextResponse
from scrapy.settings import Settings

from repub import settings as repub_settings
from repub.exporters import RssExporter
from repub.items import ElementItem
from repub.rss import nsmap
from repub.spiders.rss_spider import RssFeedSpider
from repub.utils import (
    FileType,
    local_audio_path,
    local_image_path,
    local_video_path,
    published_media_path,
)

RSS_DATE_PATTERN = re.compile(
    r"^[A-Z][a-z]{2}, \d{2} [A-Z][a-z]{2} \d{4} \d{2}:\d{2}:\d{2} [+-]\d{4}$"
)


def _published_url(feed_url: str, path: str) -> str:
    return f"{feed_url}/feeds/demo/{path}"


def _serialize_feed(
    *,
    feed_text: str,
    feed_url: str,
    prepare_item: Callable[[ElementItem], None] | None = None,
) -> tuple[str, etree._Element]:
    spider = RssFeedSpider(feed_name="demo", url="https://source.example/feed.rss")
    spider.settings = Settings(
        values={
            "REPUBLISHER_IMAGE_DIR": "images",
            "REPUBLISHER_FILE_DIR": "files",
            "REPUBLISHER_AUDIO_DIR": "audio",
            "REPUBLISHER_VIDEO_DIR": "video",
            "REPUBLISHER_AUDIO": repub_settings.REPUBLISHER_AUDIO,
            "REPUBLISHER_VIDEO": repub_settings.REPUBLISHER_VIDEO,
            "REPUBLISHER_FEED_URL": feed_url,
        }
    )
    response = TextResponse(
        url="https://source.example/feed.rss",
        body=feed_text.encode("utf-8"),
        encoding="utf-8",
    )

    output = BytesIO()
    exporter = RssExporter(output)
    exporter.start_exporting()
    for item in list(spider._parse(response) or []):
        if prepare_item is not None and isinstance(item, ElementItem):
            prepare_item(item)
        exporter.export_item(item)
    exporter.finish_exporting()

    xml = output.getvalue().decode("utf-8")
    return xml, etree.fromstring(output.getvalue())


def test_feed_generation_normalizes_dates_urls_and_xml_shapes() -> None:
    long_summary = "<p>" + ("Long summary text " * 260) + "<b>tail</b></p>"
    source_image = "https://source.example/media/photo.jpg"
    source_audio = "https://source.example/media/audio.mp3"
    source_video = "https://source.example/media/video.mp4"
    channel_image = "https://source.example/media/channel.png"
    item_image = "https://source.example/media/cover.jpg"
    audio_base_path = local_audio_path(source_audio)
    audio_default_path = published_media_path(
        FileType.AUDIO, source_audio, repub_settings.REPUBLISHER_AUDIO[0]
    )
    audio_m4a_path = published_media_path(
        FileType.AUDIO, source_audio, repub_settings.REPUBLISHER_AUDIO[1]
    )
    audio_webm_path = published_media_path(
        FileType.AUDIO, source_audio, repub_settings.REPUBLISHER_AUDIO[2]
    )
    video_base_path = local_video_path(source_video)
    video_main_path = published_media_path(
        FileType.VIDEO, source_video, repub_settings.REPUBLISHER_VIDEO[0]
    )
    video_fallback_path = published_media_path(
        FileType.VIDEO, source_video, repub_settings.REPUBLISHER_VIDEO[1]
    )

    def prepare_item(item: ElementItem) -> None:
        item.audios = [
            {
                "url": source_audio,
                "path": audio_default_path,
                "published_url": _published_url(
                    "https://mirror.example",
                    f"audio/{audio_default_path}",
                ),
                "checksum": "audio-default",
                "status": "downloaded",
                "variants": [
                    {
                        "url": _published_url(
                            "https://mirror.example",
                            f"audio/{audio_default_path}",
                        ),
                        "path": audio_default_path,
                        "type": "audio/mpeg",
                        "medium": "audio",
                        "isDefault": "true",
                        "fileSize": "4567",
                        "bitrate": "37209",
                        "duration": "61.2",
                        "samplingrate": "48000",
                        "channels": "1",
                    },
                    {
                        "url": _published_url(
                            "https://mirror.example",
                            f"audio/{audio_m4a_path}",
                        ),
                        "path": audio_m4a_path,
                        "type": "audio/mp4",
                        "medium": "audio",
                        "isDefault": "false",
                        "fileSize": "3456",
                        "bitrate": "20746",
                        "duration": "61.2",
                        "samplingrate": "48000",
                        "channels": "1",
                    },
                    {
                        "url": _published_url(
                            "https://mirror.example",
                            f"audio/{audio_webm_path}",
                        ),
                        "path": audio_webm_path,
                        "type": "audio/webm",
                        "medium": "audio",
                        "isDefault": "false",
                        "fileSize": "2345",
                        "bitrate": "48000",
                        "duration": "61.2",
                        "samplingrate": "48000",
                        "channels": "1",
                    },
                    {
                        "url": _published_url(
                            "https://mirror.example",
                            f"audio/{audio_base_path}",
                        ),
                        "path": audio_base_path,
                        "type": "audio/mpeg",
                        "medium": "audio",
                        "isDefault": "false",
                        "fileSize": "5678",
                        "bitrate": "128000",
                        "duration": "61.2",
                        "samplingrate": "44100",
                        "channels": "2",
                    },
                ],
            }
        ]
        item.videos = [
            {
                "url": source_video,
                "path": video_main_path,
                "published_url": _published_url(
                    "https://mirror.example",
                    f"video/{video_main_path}",
                ),
                "checksum": "video-default",
                "status": "downloaded",
                "variants": [
                    {
                        "url": _published_url(
                            "https://mirror.example",
                            f"video/{video_main_path}",
                        ),
                        "path": video_main_path,
                        "type": "video/mp4",
                        "medium": "video",
                        "isDefault": "true",
                        "fileSize": "9876",
                        "bitrate": "123456",
                        "duration": "60.0",
                        "width": "1280",
                        "height": "720",
                        "framerate": "30/1",
                    },
                    {
                        "url": _published_url(
                            "https://mirror.example",
                            f"video/{video_fallback_path}",
                        ),
                        "path": video_fallback_path,
                        "type": "video/webm",
                        "medium": "video",
                        "isDefault": "false",
                        "fileSize": "6789",
                        "bitrate": "64000",
                        "duration": "60.0",
                        "width": "1280",
                        "height": "720",
                        "framerate": "25/1",
                    },
                    {
                        "url": _published_url(
                            "https://mirror.example",
                            f"video/{video_base_path}",
                        ),
                        "path": video_base_path,
                        "type": "video/mp4",
                        "medium": "video",
                        "isDefault": "false",
                        "fileSize": "12345",
                        "bitrate": "456789",
                        "duration": "60.0",
                        "width": "640",
                        "height": "360",
                        "framerate": "24/1",
                    },
                ],
            }
        ]

    xml, root = _serialize_feed(
        feed_url="https://mirror.example",
        prepare_item=prepare_item,
        feed_text=f"""<?xml version="1.0" encoding="UTF-8"?>
<rss version="2.0"
     xmlns:content="http://purl.org/rss/1.0/modules/content/"
     xmlns:media="http://search.yahoo.com/mrss/"
     xmlns:itunes="http://www.itunes.com/dtds/podcast-1.0.dtd">
  <channel>
    <title>Demo Feed</title>
    <link>https://source.example/feed</link>
    <description><![CDATA[<p mode="teaser" querystring="view=full">Channel description</p>]]></description>
    <language>en-us</language>
    <webMaster>support@guardianproject.info</webMaster>
    <category>World</category>
    <pubDate>Tue, 31 Mar 2026 08:31:50 +0000</pubDate>
    <lastBuildDate>Tue, 31 Mar 2026 09:31:50 +0000</lastBuildDate>
    <image>
      <url>{channel_image}</url>
      <title>Demo Feed</title>
      <link>https://source.example/feed</link>
    </image>
    <item>
      <title>Entry One</title>
      <link>https://source.example/entry-1</link>
      <description><![CDATA[<p mode="summary" querystring="foo=bar"><img src="{source_image}" contenteditable="true"></p>]]></description>
      <guid isPermaLink="false">entry-1</guid>
      <pubDate>Tue, 31 Mar 2026 10:31:50 +0000</pubDate>
      <enclosure url="{source_audio}" length="123" type="audio/mpeg" />
      <content:encoded><![CDATA[<div mode="body" querystring="x=1"><img src="{source_image}" contenteditable="true"></div>]]></content:encoded>
      <media:content url="{source_video}" type="video/mp4" medium="video" expression="full" duration="60" width="640" height="360" lang="en" />
      <itunes:summary><![CDATA[{long_summary}]]></itunes:summary>
      <itunes:image href="{item_image}" />
    </item>
  </channel>
</rss>
""",
    )

    channel = root.find("channel")
    assert channel is not None

    last_build_date = channel.findtext("lastBuildDate")
    item_pub_date = root.findtext("./channel/item/pubDate")
    assert last_build_date is not None
    assert item_pub_date is not None
    assert RSS_DATE_PATTERN.fullmatch(last_build_date)
    assert RSS_DATE_PATTERN.fullmatch(item_pub_date)
    assert (
        channel.findtext("webMaster")
        == "support@guardianproject.info (Guardian Project)"
    )
    assert parsedate_to_datetime(last_build_date).tzinfo is not None
    assert parsedate_to_datetime(item_pub_date).tzinfo is not None
    assert last_build_date == item_pub_date
    assert channel.findtext("itunes:explicit", namespaces=nsmap) == "false"
    assert channel.findtext("./image/url") == (
        f"https://mirror.example/feeds/demo/images/{local_image_path(channel_image)}"
    )

    atom_self = channel.find("atom:link", namespaces=nsmap)
    assert atom_self is not None
    assert atom_self.attrib == {
        "rel": "self",
        "href": "https://mirror.example/feeds/demo/feed.rss",
        "type": "application/rss+xml",
    }
    itunes_category = channel.find("itunes:category", namespaces=nsmap)
    assert itunes_category is not None
    assert itunes_category.attrib == {"text": "News"}
    assert (
        channel.findtext("./itunes:owner/itunes:email", namespaces=nsmap)
        == "support@guardianproject.info"
    )

    enclosure = root.find("./channel/item/enclosure")
    assert enclosure is not None
    assert enclosure.attrib == {
        "url": (f"https://mirror.example/feeds/demo/audio/" f"{audio_default_path}"),
        "length": "4567",
        "type": "audio/mpeg",
    }
    assert len(enclosure) == 0

    assert root.find("./channel/item/media:content", namespaces=nsmap) is None

    media_groups = root.findall("./channel/item/media:group", namespaces=nsmap)
    assert len(media_groups) == 2

    audio_group, video_group = media_groups
    audio_variants = audio_group.findall("media:content", namespaces=nsmap)
    assert [variant.attrib for variant in audio_variants] == [
        {
            "url": (
                f"https://mirror.example/feeds/demo/audio/" f"{audio_default_path}"
            ),
            "type": "audio/mpeg",
            "medium": "audio",
            "isDefault": "true",
            "bitrate": "37209",
            "samplingrate": "48000",
            "channels": "1",
            "duration": "61.2",
            "fileSize": "4567",
        },
        {
            "url": (f"https://mirror.example/feeds/demo/audio/" f"{audio_m4a_path}"),
            "type": "audio/mp4",
            "medium": "audio",
            "isDefault": "false",
            "bitrate": "20746",
            "samplingrate": "48000",
            "channels": "1",
            "duration": "61.2",
            "fileSize": "3456",
        },
        {
            "url": (f"https://mirror.example/feeds/demo/audio/" f"{audio_webm_path}"),
            "type": "audio/webm",
            "medium": "audio",
            "isDefault": "false",
            "bitrate": "48000",
            "samplingrate": "48000",
            "channels": "1",
            "duration": "61.2",
            "fileSize": "2345",
        },
        {
            "url": (
                f"https://mirror.example/feeds/demo/audio/"
                f"{local_audio_path(source_audio)}"
            ),
            "type": "audio/mpeg",
            "medium": "audio",
            "isDefault": "false",
            "bitrate": "128000",
            "samplingrate": "44100",
            "channels": "2",
            "duration": "61.2",
            "fileSize": "5678",
        },
    ]

    video_variants = video_group.findall("media:content", namespaces=nsmap)
    assert [variant.attrib for variant in video_variants] == [
        {
            "url": (f"https://mirror.example/feeds/demo/video/" f"{video_main_path}"),
            "type": "video/mp4",
            "medium": "video",
            "isDefault": "true",
            "expression": "full",
            "bitrate": "123456",
            "framerate": "30/1",
            "duration": "60.0",
            "height": "720",
            "width": "1280",
            "lang": "en",
            "fileSize": "9876",
        },
        {
            "url": (
                f"https://mirror.example/feeds/demo/video/" f"{video_fallback_path}"
            ),
            "type": "video/webm",
            "medium": "video",
            "isDefault": "false",
            "expression": "full",
            "bitrate": "64000",
            "framerate": "25/1",
            "duration": "60.0",
            "height": "720",
            "width": "1280",
            "lang": "en",
            "fileSize": "6789",
        },
        {
            "url": (
                f"https://mirror.example/feeds/demo/video/"
                f"{local_video_path(source_video)}"
            ),
            "type": "video/mp4",
            "medium": "video",
            "isDefault": "false",
            "expression": "full",
            "bitrate": "456789",
            "framerate": "24/1",
            "duration": "60.0",
            "height": "360",
            "width": "640",
            "lang": "en",
            "fileSize": "12345",
        },
    ]

    itunes_image = root.find("./channel/item/itunes:image", namespaces=nsmap)
    assert itunes_image is not None
    assert itunes_image.attrib == {
        "href": f"https://mirror.example/feeds/demo/images/{local_image_path(item_image)}"
    }

    itunes_summary = root.findtext("./channel/item/itunes:summary", namespaces=nsmap)
    assert itunes_summary is not None
    assert len(itunes_summary) <= 4000
    assert "<" not in itunes_summary
    assert ">" not in itunes_summary


def test_item_body_uses_description_only_when_content_is_also_present() -> None:
    xml, root = _serialize_feed(
        feed_url="https://mirror.example",
        feed_text="""<?xml version="1.0" encoding="UTF-8"?>
<rss version="2.0"
     xmlns:content="http://purl.org/rss/1.0/modules/content/">
  <channel>
    <title>Demo Feed</title>
    <link>https://source.example/feed</link>
    <description>Demo description</description>
    <item>
      <title>Description Only</title>
      <link>https://source.example/description-only</link>
      <description><![CDATA[<p mode="summary">Description body</p>]]></description>
      <guid isPermaLink="false">entry-description-only</guid>
      <pubDate>Tue, 31 Mar 2026 10:31:50 +0000</pubDate>
    </item>
    <item>
      <title>Content Only</title>
      <link>https://source.example/content-only</link>
      <guid isPermaLink="false">entry-content-only</guid>
      <pubDate>Tue, 31 Mar 2026 10:31:50 +0000</pubDate>
      <content:encoded><![CDATA[<div mode="body">Content body</div>]]></content:encoded>
    </item>
    <item>
      <title>Both Present</title>
      <link>https://source.example/both-present</link>
      <description><![CDATA[<p mode="summary">Summary body</p>]]></description>
      <guid isPermaLink="false">entry-both-present</guid>
      <pubDate>Tue, 31 Mar 2026 10:31:50 +0000</pubDate>
      <content:encoded><![CDATA[<div mode="body">Full body</div>]]></content:encoded>
    </item>
  </channel>
</rss>
""",
    )

    items = root.findall("./channel/item")
    assert len(items) == 3

    description_only, content_only, both_present = items

    assert description_only.findtext("description") in (None, "")
    assert description_only.findtext("content:encoded", namespaces=nsmap) == (
        "<p>Description body</p>"
    )

    assert content_only.findtext("description") in (None, "")
    assert content_only.findtext("content:encoded", namespaces=nsmap) == (
        "<div>Content body</div>"
    )

    assert both_present.findtext("description") == "<p>Summary body</p>"
    assert both_present.findtext("content:encoded", namespaces=nsmap) == (
        "<div>Full body</div>"
    )