"""Skills Scanner — Scan skills/ directory and generate SKILLS_SNAPSHOT.md."""

from pathlib import Path

import yaml


def discover_skills(base_dir: Path) -> list[dict]:
    """Read the native Skills catalog without changing its generated snapshot."""
    root = (base_dir / "skills").resolve()
    entries = []
    for file in sorted(root.rglob("SKILL.md")):
        resolved = file.resolve()
        if not resolved.is_relative_to(root):
            continue
        try:
            content = file.read_text(encoding="utf-8")
            if not content.startswith("---"):
                continue
            parts = content.split("---", 2)
            meta = yaml.safe_load(parts[1]) if len(parts) == 3 else None
            if not isinstance(meta, dict):
                continue
            entries.append({"id":file.relative_to(root).as_posix(),"name":str(meta.get("name",file.parent.name)),"description":str(meta.get("description","")),"content":content})
        except (OSError, ValueError, yaml.YAMLError):
            continue
    return entries


def scan_skills(base_dir: Path) -> str:
    """Scan all SKILL.md files and generate SKILLS_SNAPSHOT.md."""
    skills_dir = base_dir / "skills"
    snapshot_path = base_dir / "SKILLS_SNAPSHOT.md"

    if not skills_dir.exists():
        skills_dir.mkdir(parents=True)

    skills = [{**s, "location":f"./backend/skills/{s['id']}"} for s in discover_skills(base_dir)]

    # Build XML-style snapshot
    lines = ["<available_skills>"]
    for s in skills:
        lines.append("  <skill>")
        lines.append(f"    <name>{s['name']}</name>")
        lines.append(f"    <description>{s['description']}</description>")
        lines.append(f"    <location>{s['location']}</location>")
        lines.append("  </skill>")
    lines.append("</available_skills>")

    snapshot = "\n".join(lines)
    snapshot_path.write_text(snapshot, encoding="utf-8")
    print(f"📋 Skills snapshot: {len(skills)} skills found")
    return snapshot