from typing import Any
import xml.etree.ElementTree as ET

from tinydb import Query

from app.Item import Item
from app.PluginInterface import PluginInterface
from app.utils import get_param
from app.database import database_manager


class Plugin(PluginInterface):
    def __init__(self, id: str, params: dict[str, Any]) -> None:
        super().__init__(id, params)
        self.feed_id: str = get_param("feed_id", params)
        self.feed_title: str = get_param("feed_title", params)
        self.feed_link: str | None = params.get("feed_link", None)
        self.feed_description: str = get_param("feed_description", params)
        print(f"[FeedSinkPlugin#{self.id}] initialized")
        print(f"[FeedSinkPlugin#{self.id}] feed will be served at path /{self.feed_id}")

    def build_xml(self, items: list[Item]):
        rss = ET.Element("rss", {"version": "2.0"})
        channel = ET.SubElement(rss, "channel")
        title = ET.SubElement(channel, "title")
        title.text = self.feed_title
        if self.feed_link is not None:
            link = ET.SubElement(channel, "link")
            link.text = self.feed_link
        description = ET.SubElement(channel, "description")
        description.text = self.feed_description

        for item in items:
            item_elem = ET.SubElement(channel, "item")
            item_title = ET.SubElement(item_elem, "title")
            item_title.text = item.title
            item_link = ET.SubElement(item_elem, "link")
            item_link.text = item.link
            item_description = ET.SubElement(item_elem, "description")
            item_description.text = item.description

        return ET.tostring(rss, "unicode")

    def process(self, source_id: str | None, items: list[Item]) -> list[Item]:
        print(f"[FeedSinkPlugin#{self.id}] process called, n={len(items)}")

        if source_id is None:
            raise Exception(f"FeedSinkPlugin#{self.id} can not be scheduled")
        if database_manager.db is None:
            raise Exception("Database is not initialized")

        ret = self.build_xml(items)

        Q = Query()
        database_manager.db.upsert({"feed_id": self.feed_id, "feed_xml": ret}, Q.feed_id == self.feed_id)  # type: ignore
        print(f"[FeedSinkPlugin#{self.id}] processed")
        return []