from structure_builder import (
    DefinitionElement,
    HeadingElement,
    ImageElement,
    ImportantElement,
    OrderedListElement,
    ParagraphElement,
    Structure,
    StructureElement,
    UnorderedListElement,
)
from utils import Event, Timeline


class MarkdownBuilder:
    """Render a document structure to Markdown without using AI."""

    def __init__(self, timeline: Timeline) -> None:
        self._events: dict[int, Event] = {}
        for event in timeline.events:
            if event.id in self._events:
                raise ValueError(f"Duplicate event ID: {event.id}")
            self._events[event.id] = event

    def _render_image(self, element: ImageElement) -> str:
        event = self._events.get(element.event_id)
        if event is None or event.type != "vis" or not event.payload:
            raise ValueError(
                f"Image element references invalid visual event: {element.event_id}"
            )
        alt = event.text.replace("[", "").replace("]", "").replace("\n", " ")
        return f"![{alt}](<{event.payload}>)"

    def _render_element(self, element: StructureElement) -> str:
        if isinstance(element, HeadingElement):
            return f"{'#' * element.level} {element.text}"
        if isinstance(element, ParagraphElement):
            return element.text
        if isinstance(element, UnorderedListElement):
            return "\n".join(f"- {item}" for item in element.items)
        if isinstance(element, OrderedListElement):
            return "\n".join(
                f"{index}. {item}"
                for index, item in enumerate(element.items, start=1)
            )
        if isinstance(element, DefinitionElement):
            return f"**{element.term}.** {element.text}"
        if isinstance(element, ImportantElement):
            text = f"**Важно:** {element.text}"
            return "\n".join(f"> {line}" for line in text.splitlines())
        if isinstance(element, ImageElement):
            return self._render_image(element)
        raise TypeError(f"Unsupported structure element: {type(element).__name__}")

    def build(self, structure: Structure) -> str:
        blocks = [self._render_element(element) for element in structure.elements]
        if not blocks:
            return ""
        return "\n\n".join(blocks) + "\n"