"""
ctstruct/renderers/markdown.py
CTTree → Markdown 렌더러
"""

from __future__ import annotations

from ..node import CTNode
from ..tree import CTTree
from ..types import NodeType
from .base import BaseRenderer


class MarkdownRenderer(BaseRenderer):
    """CTTree 를 Markdown 텍스트로 렌더링."""

    def render(self, tree: CTTree) -> str:
        lines: list[str] = []
        # frontmatter
        meta = tree.root.attr("metadata")
        if meta:
            lines.append("---")
            for k, v in meta.items():
                lines.append(f"{k}: {v}")
            lines.append("---")
            lines.append("")

        for child in tree.root:
            lines.extend(self._render_node(child))
            lines.append("")

        return "\n".join(lines).rstrip() + "\n"

    def _render_node(self, node: CTNode) -> list[str]:
        t = node.node_type

        if t == NodeType.SECTION:
            out: list[str] = []
            for c in node:
                out.extend(self._render_node(c))
                out.append("")
            return out

        if t == NodeType.HEADING:
            level = node.attr("level", 1)
            return [f"{'#' * level} {node.content or ''}"]

        if t == NodeType.PARAGRAPH:
            return [node.content or ""]

        if t == NodeType.CODE_BLOCK:
            lang = node.attr("language", "")
            return [f"```{lang}", node.content or "", "```"]

        if t == NodeType.BLOCKQUOTE:
            return [f"> {line}" for line in (node.content or "").splitlines()]

        if t == NodeType.DIVIDER:
            return ["---"]

        if t == NodeType.LIST:
            out = []
            style = node.attr("style", "unordered")
            for idx, item in enumerate(node, 1):
                prefix = f"{idx}." if style == "ordered" else "-"
                out.append(f"{prefix} {item.content or ''}")
            return out

        if t == NodeType.TABLE:
            return self._render_table(node)

        if t == NodeType.METADATA:
            return []  # 메타 노드는 frontmatter로 처리됨

        # 그 외 노드는 텍스트 추출
        return [node.text_content()]

    def _render_table(self, table: CTNode) -> list[str]:
        rows = list(table)
        if not rows:
            return []
        out: list[str] = []
        for i, row in enumerate(rows):
            cells = [c.content or "" for c in row]
            out.append("| " + " | ".join(cells) + " |")
            if i == 0:
                out.append("| " + " | ".join(["---"] * len(cells)) + " |")
        return out