#!/usr/bin/env python3
"""
Generate README.md and AGENTS.md from templates.
Usage:
    python scripts/update_docs.py
"""

import json
from pathlib import Path


SCRIPT_DIR = Path(__file__).parent
PROJECT_ROOT = SCRIPT_DIR.parent
TEMPLATES_DIR = PROJECT_ROOT / "docs" / "templates"
DECKS_DIR = PROJECT_ROOT / "decks"
COLLECTION_DIR = PROJECT_ROOT / "collection_hydrated"


def load_decks() -> list[dict]:
    """Load all deck JSON files."""
    decks = []
    if DECKS_DIR.exists():
        for path in sorted(DECKS_DIR.glob("*.json")):
            with open(path, "r", encoding="utf-8") as f:
                data = json.load(f)
                data["filename"] = path.stem
                decks.append(data)
    return decks


def load_collection_stats() -> dict:
    """Get collection statistics."""
    stats = {
        "total_cards": 0,
        "unique_cards": 0,
        "by_type": {}
    }
    deck_file = COLLECTION_DIR / "deck.json"
    if deck_file.exists():
        with open(deck_file, "r", encoding="utf-8") as f:
            cards = json.load(f)
            stats["unique_cards"] = len(cards)
            stats["total_cards"] = sum(c.get("count", 1) for c in cards)
    for category in ["creatures", "instants", "sorceries", "artifacts", "enchantments", "lands", "planeswalkers"]:
        cat_file = COLLECTION_DIR / f"{category}.json"
        if cat_file.exists():
            with open(cat_file, "r", encoding="utf-8") as f:
                cards = json.load(f)
                stats["by_type"][category] = len(cards)
    return stats


def generate_deck_table(decks: list[dict]) -> str:
    """Generate markdown table of decks."""
    if not decks:
        return "*No decks defined yet.*"
    lines = ["| Deck | Colors | Commander | Archetype |", "|------|--------|-----------|-----------|"]
    for deck in decks:
        name = deck.get("name", deck.get("filename", "Unknown"))
        colors = deck.get("colors", [])
        color_str = "".join(colors) if colors else "Colorless"
        commander = deck.get("commander", "Unknown")
        archetype = deck.get("archetype", "-")
        lines.append(f"| {name} | {color_str} | {commander} | {archetype} |")
    return "\n".join(lines)


def generate_collection_stats(stats: dict) -> str:
    """Generate collection statistics section."""
    lines = [f"- **Total cards:** {stats['total_cards']}", f"- **Unique cards:** {stats['unique_cards']}"]
    if stats["by_type"]:
        lines.append("- **By type:**")
        for category, count in sorted(stats["by_type"].items()):
            lines.append(f"  - {category.title()}: {count}")
    return "\n".join(lines)


def generate_docs() -> None:
    """Generate README.md and AGENTS.md from templates."""
    decks = load_decks()
    stats = load_collection_stats()
    deck_table = generate_deck_table(decks)
    collection_stats = generate_collection_stats(stats)
    
    for template_name in ["README.template.md", "AGENTS.template.md"]:
        template_path = TEMPLATES_DIR / template_name
        if not template_path.exists():
            print(f"Template not found: {template_path}")
            continue
        with open(template_path, "r", encoding="utf-8") as f:
            content = f.read()
        content = content.replace("{{DECK_TABLE}}", deck_table)
        content = content.replace("{{COLLECTION_STATS}}", collection_stats)
        output_name = template_name.replace(".template", "")
        output_path = PROJECT_ROOT / output_name
        with open(output_path, "w", encoding="utf-8") as f:
            f.write(content)
        print(f"Generated: {output_path}")


if __name__ == "__main__":
    generate_docs()