#!/usr/bin/env python3
import argparse
import datetime
import json
import os
import pathlib
import shutil
from typing import Dict, List

ROOT = pathlib.Path(__file__).resolve().parents[1]


def load_catalog(path: pathlib.Path) -> List[Dict[str, object]]:
    with path.open("r", encoding="utf-8") as handle:
        return json.load(handle)


def build_app_id(slug: str) -> str:
    sanitized = ''.join(ch.lower() if ch.isalnum() else '.' for ch in slug)
    sanitized = '.'.join(filter(None, sanitized.split('.')))
    return f"com.knel.{sanitized}"


def default_tags() -> List[str]:
    return ["custom", "known-element"]


def default_placeholder_map(entry: Dict[str, object]) -> Dict[str, str]:
    slug = entry["slug"]
    title = entry["title"]
    repo = entry["repo"]
    issue = entry.get("issue", "")
    website = entry.get("website") or repo.rstrip(".git")
    description = entry.get("description") or "TODO: Add package description."
    tags = entry.get("tags") or default_tags()
    http_port = str(entry.get("httpPort", 3000))
    base_image = entry.get("baseImage", "cloudron/base:5.0.0")

    placeholder_map = {
        "{{APP_ID}}": build_app_id(slug),
        "{{APP_TITLE}}": title,
        "{{APP_SLUG}}": slug,
        "{{APP_REPO}}": repo,
        "{{APP_ISSUE}}": issue,
        "{{APP_WEBSITE}}": website,
        "{{APP_DESCRIPTION}}": description,
        "{{HTTP_PORT}}": http_port,
        "{{BASE_IMAGE}}": base_image,
        "{{APP_TAGS}}": json.dumps(tags)
    }

    return placeholder_map


def render_templates(template_dir: pathlib.Path, destination: pathlib.Path, entry: Dict[str, object]) -> None:
    shutil.copytree(template_dir, destination, dirs_exist_ok=True)

    placeholders = default_placeholder_map(entry)

    for path in destination.rglob('*'):
        if path.is_dir():
            continue
        text = path.read_text(encoding='utf-8')
        for key, value in placeholders.items():
            text = text.replace(key, value)
        path.write_text(text, encoding='utf-8')

    # Ensure critical scripts are executable
    for relpath in ["start.sh", "test/smoke.sh"]:
        target = destination / relpath
        if target.exists():
            mode = target.stat().st_mode
            target.chmod(mode | 0o111)

    # Drop metadata file for bookkeeping
    metadata = {
        "slug": entry["slug"],
        "title": entry["title"],
        "issue": entry.get("issue"),
        "repo": entry.get("repo"),
        "additionalRepos": entry.get("additionalRepos", []),
        "created": datetime.datetime.utcnow().replace(microsecond=0).isoformat() + "Z",
        "notes": entry.get("notes", "TODO: capture packaging notes")
    }
    with (destination / "metadata.json").open("w", encoding="utf-8") as handle:
        json.dump(metadata, handle, indent=2)


def ensure_app_directory(entry: Dict[str, object], template_dir: pathlib.Path, apps_dir: pathlib.Path, force: bool) -> pathlib.Path:
    app_dir = apps_dir / entry["slug"]
    if app_dir.exists():
        if not force:
            raise FileExistsError(f"Destination {app_dir} already exists. Use --force to overwrite.")
        shutil.rmtree(app_dir)
    render_templates(template_dir, app_dir, entry)
    return app_dir


def main() -> None:
    parser = argparse.ArgumentParser(description="Scaffold Cloudron app packages from catalog entries")
    parser.add_argument("--slug", help="Generate scaffold for a single slug", default=None)
    parser.add_argument("--catalog", default=str(ROOT / "apps" / "catalog.json"), help="Path to catalog JSON")
    parser.add_argument("--template", default=str(ROOT / "templates" / "cloudron-app"), help="Template directory")
    parser.add_argument("--apps-dir", default=str(ROOT / "apps"), help="Destination apps directory")
    parser.add_argument("--force", action="store_true", help="Overwrite existing app directory")
    args = parser.parse_args()

    catalog = load_catalog(pathlib.Path(args.catalog))

    entries = catalog
    if args.slug:
        entries = [entry for entry in catalog if entry["slug"] == args.slug]
        if not entries:
            raise SystemExit(f"Slug {args.slug} not found in catalog")

    template_dir = pathlib.Path(args.template)
    apps_dir = pathlib.Path(args.apps_dir)
    apps_dir.mkdir(parents=True, exist_ok=True)

    for entry in entries:
        app_dir = ensure_app_directory(entry, template_dir, apps_dir, args.force)
        print(f"Created {app_dir.relative_to(ROOT)}")


if __name__ == "__main__":
    main()