#!/usr/bin/env python3
"""
Show information about available skills.
Usage: python3 skill-info.py [--scripts] [name]
"""

import argparse
import json
import re
import sys
from pathlib import Path
from typing import Dict, List, Optional

CLAUDE_DIR = Path.home() / ".claude"
SKILLS_DIR = CLAUDE_DIR / "skills"
REGISTRY_PATH = CLAUDE_DIR / "state" / "component-registry.json"


def load_registry() -> Dict:
    """Load component registry."""
    try:
        with open(REGISTRY_PATH) as f:
            return json.load(f)
    except (FileNotFoundError, json.JSONDecodeError):
        return {}


def find_skills() -> List[Path]:
    """Find all skill directories with SKILL.md."""
    if not SKILLS_DIR.exists():
        return []

    return [d for d in SKILLS_DIR.iterdir()
            if d.is_dir() and (d / "SKILL.md").exists()]


def parse_skill_md(path: Path) -> Dict:
    """Parse a SKILL.md file for metadata."""
    try:
        content = path.read_text()

        result = {
            "name": path.parent.name,
            "path": str(path.relative_to(CLAUDE_DIR)),
            "description": "",
            "allowed_tools": [],
        }

        # Parse YAML frontmatter
        if content.startswith("---"):
            parts = content.split("---", 2)
            if len(parts) >= 2:
                frontmatter = parts[1]
                for line in frontmatter.strip().split("\n"):
                    if ":" in line:
                        key, value = line.split(":", 1)
                        key = key.strip()
                        value = value.strip()
                        if key == "description":
                            result["description"] = value
                        elif key == "allowed-tools":
                            result["allowed_tools"] = [t.strip() for t in value.split(",")]

        # Get first paragraph as description if not in frontmatter
        if not result["description"]:
            body = content.split("---")[-1] if "---" in content else content
            lines = body.strip().split("\n\n")
            for para in lines:
                if para.strip() and not para.startswith("#"):
                    result["description"] = para.strip()[:200]
                    break

        return result

    except Exception as e:
        return {"name": path.parent.name, "error": str(e)}


def get_skill_scripts(skill_dir: Path) -> List[str]:
    """Get list of scripts in a skill's scripts/ directory."""
    scripts_dir = skill_dir / "scripts"
    if not scripts_dir.exists():
        return []

    scripts = []
    for f in scripts_dir.iterdir():
        if f.is_file() and f.suffix in [".py", ".sh"]:
            scripts.append(f.name)
    return sorted(scripts)


def get_skill_references(skill_dir: Path) -> List[str]:
    """Get list of reference files in a skill's references/ directory."""
    refs_dir = skill_dir / "references"
    if not refs_dir.exists():
        return []

    refs = []
    for f in refs_dir.iterdir():
        if f.is_file():
            refs.append(f.name)
    return sorted(refs)


def list_skills(show_scripts: bool = False):
    """List all available skills."""
    registry = load_registry()
    reg_skills = registry.get("skills", {})

    skills = find_skills()

    if not skills:
        print("No skills found.")
        return

    print(f"\n🎯 Available Skills ({len(skills)})\n")

    for skill_dir in sorted(skills):
        name = skill_dir.name
        skill_info = parse_skill_md(skill_dir / "SKILL.md")
        reg_info = reg_skills.get(name, {})

        desc = skill_info.get("description", reg_info.get("description", "No description"))
        if len(desc) > 80:
            desc = desc[:77] + "..."

        print(f"  {name}")
        print(f"    {desc}")

        if show_scripts:
            scripts = get_skill_scripts(skill_dir)
            if scripts:
                print(f"    Scripts: {', '.join(scripts)}")

        triggers = reg_info.get("triggers", [])
        if triggers:
            trigger_str = ", ".join(triggers[:4])
            if len(triggers) > 4:
                trigger_str += f" (+{len(triggers)-4} more)"
            print(f"    Triggers: {trigger_str}")

        print("")


def show_skill(name: str):
    """Show details for a specific skill."""
    # Find matching skill
    skills = find_skills()
    matches = [s for s in skills if name.lower() in s.name.lower()]

    if not matches:
        print(f"Skill '{name}' not found.")
        print("\nAvailable skills:")
        for s in sorted(skills):
            print(f"  - {s.name}")
        return

    if len(matches) > 1 and not any(s.name == name for s in matches):
        print(f"Multiple matches for '{name}':")
        for s in matches:
            print(f"  - {s.name}")
        return

    skill_dir = next((s for s in matches if s.name == name), matches[0])
    skill_info = parse_skill_md(skill_dir / "SKILL.md")

    registry = load_registry()
    reg_info = registry.get("skills", {}).get(skill_dir.name, {})

    print(f"\n🎯 Skill: {skill_dir.name}\n")
    print(f"Path: {skill_dir.relative_to(CLAUDE_DIR)}/")
    print(f"Description: {skill_info.get('description', 'No description')}")

    # Allowed tools
    allowed = skill_info.get("allowed_tools", [])
    if allowed:
        print(f"\nAllowed Tools: {', '.join(allowed)}")

    # Triggers
    triggers = reg_info.get("triggers", [])
    if triggers:
        print(f"\nTriggers:")
        for t in triggers:
            print(f"  - {t}")

    # Scripts
    scripts = get_skill_scripts(skill_dir)
    if scripts:
        print(f"\nScripts:")
        for s in scripts:
            script_path = skill_dir / "scripts" / s
            executable = "✓" if script_path.stat().st_mode & 0o111 else "○"
            print(f"  {executable} {s}")

    # References
    refs = get_skill_references(skill_dir)
    if refs:
        print(f"\nReferences:")
        for r in refs:
            print(f"  - {r}")

    # Registry script
    if "script" in reg_info:
        print(f"\nRegistry Script: {reg_info['script']}")

    print("")


def main():
    parser = argparse.ArgumentParser(description="Show skill information")
    parser.add_argument("name", nargs="?", help="Skill name to show details")
    parser.add_argument("--scripts", "-s", action="store_true",
                       help="Show scripts in listing")
    parser.add_argument("--list", "-l", action="store_true", help="List all skills")

    args = parser.parse_args()

    if args.name and not args.list:
        show_skill(args.name)
    else:
        list_skills(args.scripts)


if __name__ == "__main__":
    main()