import json
from datetime import datetime, timezone
from pathlib import Path
from typing import Any
from uuid import uuid4

from app.config import settings


class JsonStore:
    def __init__(self) -> None:
        self.root = Path(settings.state_dir)
        self.root.mkdir(parents=True, exist_ok=True)

    def _path(self, name: str) -> Path:
        return self.root / f"{name}.json"

    def load(self, name: str, default: Any) -> Any:
        path = self._path(name)
        if not path.exists():
            return default
        return json.loads(path.read_text())

    def save(self, name: str, value: Any) -> Any:
        path = self._path(name)
        path.write_text(json.dumps(value, indent=2, sort_keys=True))
        return value

    def replace_collection(self, name: str, items: list[dict[str, Any]]) -> list[dict[str, Any]]:
        return self.save(name, items)

    def append_collection(self, name: str, item: dict[str, Any]) -> dict[str, Any]:
        items = self.load(name, [])
        items.append(item)
        self.save(name, items)
        return item

    def update_collection_item(self, name: str, predicate, updater):
        items = self.load(name, [])
        updated = None
        for idx, item in enumerate(items):
            if predicate(item):
                items[idx] = updater(dict(item))
                updated = items[idx]
                break
        self.save(name, items)
        return updated

    def now(self) -> str:
        return datetime.now(timezone.utc).isoformat()

    def new_id(self, prefix: str) -> str:
        return f"{prefix}-{uuid4().hex[:12]}"