"""Parse governance documents with YAML frontmatter.

Expected format:
---
doc_id: spore.governance.consent
doc_kind: protocol
status: active
depends_on:
  - spore.governance.membrane
  - spore.governance.holons
---

# Document Title

Body content here...
"""

import frontmatter
from pydantic import BaseModel


class GovernanceDoc(BaseModel):
    doc_id: str
    doc_kind: str
    title: str = ""
    status: str = "draft"
    depends_on: list[str] = []
    body: str = ""
    frontmatter: dict = {}


def parse_governance_doc(content: str) -> GovernanceDoc:
    """Parse a markdown document with YAML frontmatter into a GovernanceDoc."""
    post = frontmatter.loads(content)
    meta = dict(post.metadata)

    doc_id = meta.pop("doc_id", "")
    if not doc_id:
        raise ValueError("Missing required frontmatter field: doc_id")

    doc_kind = meta.pop("doc_kind", "document")
    status = meta.pop("status", "draft")
    depends_on = meta.pop("depends_on", [])
    title = meta.pop("title", "")

    # Extract title from first heading if not in frontmatter
    if not title:
        for line in post.content.split("\n"):
            stripped = line.strip()
            if stripped.startswith("# "):
                title = stripped[2:].strip()
                break

    return GovernanceDoc(
        doc_id=doc_id,
        doc_kind=doc_kind,
        title=title,
        status=status,
        depends_on=depends_on if isinstance(depends_on, list) else [depends_on],
        body=post.content,
        frontmatter=meta,
    )


def parse_many(contents: list[str]) -> list[GovernanceDoc]:
    """Parse multiple governance documents."""
    return [parse_governance_doc(c) for c in contents]