from dataclasses import dataclass, field
from typing import Optional

from bebop.gemtext import parse_gemtext
from bebop.metalines import (
    RenderOptions, generate_dumb_metalines, generate_metalines)
from bebop.mime import MimeType
from bebop.links import Links


def get_render_options(config: dict):
    """Prepare RenderOptions from the user config."""
    return RenderOptions(
        width=config["text_width"],
        mode=config["render_mode"],
        bullet=config["list_item_bullet"],
    )


@dataclass
class Page:
    """Page-related data.

    Attributes:
    - source: str used to create the page.
    - metalines: lines ready to be rendered.
    - links: Links instance, mapping IDs to links on the page; this data is
      redundant as the links' URLs/IDs are already available in the
      corresponding metalines, it is meant to be used as a quick map for link ID
      lookup and disambiguation.
    - title: optional page title.
    - mime: optional MIME type received from the server.
    - encoding: optional encoding received from the server.
    - render_opts: optional render options used to create the page from Gemtext.
    """
    source: str
    metalines: list = field(default_factory=list)
    links: Links = field(default_factory=Links)
    title: str = ""
    mime: Optional[MimeType] = None
    encoding: str = ""
    render_opts: Optional[RenderOptions] = None

    @staticmethod
    def from_gemtext(gemtext: str, options: RenderOptions):
        """Produce a Page from a Gemtext file or string."""
        dumb = options.mode == "dumb"
        elements, links, title = parse_gemtext(gemtext, dumb=dumb)
        metalines = generate_metalines(elements, options)
        return Page(
            gemtext,
            metalines,
            links,
            title,
            render_opts=options
        )

    @staticmethod
    def from_text(text: str):
        """Produce a Page for a text string."""
        metalines = generate_dumb_metalines(text.splitlines())
        return Page(text, metalines)