"""Template storage using JSON files."""

import uuid
from datetime import datetime, timezone
from typing import Dict, List, Optional

from wled_controller.core.capture_engines.factory import EngineRegistry
from wled_controller.storage.base_store import BaseJsonStore
from wled_controller.storage.template import CaptureTemplate
from wled_controller.utils import get_logger

logger = get_logger(__name__)


class TemplateStore(BaseJsonStore[CaptureTemplate]):
    """Storage for capture templates.

    All templates are persisted to the JSON file.
    On startup, if no templates exist, one is auto-created using the
    highest-priority available engine.
    """

    _json_key = "templates"
    _entity_name = "Capture template"

    def __init__(self, file_path: str):
        super().__init__(file_path, CaptureTemplate.from_dict)
        self._ensure_initial_template()

    # Backward-compatible aliases
    get_all_templates = BaseJsonStore.get_all
    get_template = BaseJsonStore.get
    delete_template = BaseJsonStore.delete

    def _ensure_initial_template(self) -> None:
        """Auto-create a template if none exist, using the best available engine."""
        if self._items:
            return

        best_engine = EngineRegistry.get_best_available_engine()
        if not best_engine:
            logger.warning("No capture engines available, cannot create initial template")
            return

        engine_class = EngineRegistry.get_engine(best_engine)
        default_config = engine_class.get_default_config()
        now = datetime.now(timezone.utc)
        template_id = f"tpl_{uuid.uuid4().hex[:8]}"

        template = CaptureTemplate(
            id=template_id,
            name="Default",
            engine_type=best_engine,
            engine_config=default_config,
            created_at=now,
            updated_at=now,
            description=f"Default capture template using {best_engine.upper()} engine",
        )

        self._items[template_id] = template
        self._save()
        logger.info(f"Auto-created initial template: {template.name} ({template_id}, engine={best_engine})")

    def create_template(
        self,
        name: str,
        engine_type: str,
        engine_config: Dict[str, any],
        description: Optional[str] = None,
        tags: Optional[List[str]] = None,
    ) -> CaptureTemplate:
        self._check_name_unique(name)

        template_id = f"tpl_{uuid.uuid4().hex[:8]}"
        now = datetime.now(timezone.utc)
        template = CaptureTemplate(
            id=template_id,
            name=name,
            engine_type=engine_type,
            engine_config=engine_config,
            created_at=now,
            updated_at=now,
            description=description,
            tags=tags or [],
        )

        self._items[template_id] = template
        self._save()

        logger.info(f"Created template: {name} ({template_id})")
        return template

    def update_template(
        self,
        template_id: str,
        name: Optional[str] = None,
        engine_type: Optional[str] = None,
        engine_config: Optional[Dict[str, any]] = None,
        description: Optional[str] = None,
        tags: Optional[List[str]] = None,
    ) -> CaptureTemplate:
        template = self.get(template_id)

        if name is not None:
            self._check_name_unique(name, exclude_id=template_id)
            template.name = name
        if engine_type is not None:
            template.engine_type = engine_type
        if engine_config is not None:
            template.engine_config = engine_config
        if description is not None:
            template.description = description
        if tags is not None:
            template.tags = tags

        template.updated_at = datetime.now(timezone.utc)
        self._save()

        logger.info(f"Updated template: {template_id}")
        return template