"""
Recipe Service - business logic for recipe management.

Recipes are content-addressed YAML files stored in the cache (and IPFS).
The recipe ID is the content hash of the YAML file.
"""

import tempfile
from pathlib import Path
from typing import Optional, List, Dict, Any, Tuple

import yaml


class RecipeService:
    """
    Service for managing recipes.

    Recipes are stored in the content-addressed cache, not Redis.
    """

    def __init__(self, redis, cache):
        # Redis kept for compatibility but not used for recipe storage
        self.redis = redis
        self.cache = cache

    async def get_recipe(self, recipe_id: str) -> Optional[Dict[str, Any]]:
        """Get a recipe by ID (content hash)."""
        # Get from cache (content-addressed storage)
        path = self.cache.get_by_content_hash(recipe_id)
        if not path or not path.exists():
            return None

        with open(path) as f:
            recipe_data = yaml.safe_load(f)

        # Add the recipe_id to the data for convenience
        if isinstance(recipe_data, dict):
            recipe_data["recipe_id"] = recipe_id
            # Get IPFS CID if available
            ipfs_cid = self.cache.get_ipfs_cid(recipe_id)
            if ipfs_cid:
                recipe_data["ipfs_cid"] = ipfs_cid

        return recipe_data

    async def list_recipes(self, actor_id: str = None, offset: int = 0, limit: int = 20) -> list:
        """
        List available recipes.

        Note: This scans the cache for recipe files. For production,
        you might want a database index of recipes by owner.
        """
        # Get all cached items and filter for recipes
        # This is a simplified implementation - production would use a proper index
        recipes = []

        # Check if cache has a list method for recipes
        if hasattr(self.cache, 'list_by_type'):
            items = self.cache.list_by_type('recipe')
            for content_hash in items:
                recipe = await self.get_recipe(content_hash)
                if recipe:
                    # Filter by actor if specified
                    if actor_id is None or recipe.get("uploader") == actor_id:
                        recipes.append(recipe)

        # Sort by name
        recipes.sort(key=lambda r: r.get("name", ""))

        # Paginate
        return recipes[offset:offset + limit]

    async def upload_recipe(
        self,
        yaml_content: str,
        uploader: str,
        name: str = None,
        description: str = None,
    ) -> Tuple[Optional[str], Optional[str]]:
        """
        Upload a recipe from YAML content.

        The recipe is stored in the cache and optionally pinned to IPFS.
        Returns (recipe_id, error_message).
        """
        # Validate YAML
        try:
            recipe_data = yaml.safe_load(yaml_content)
        except yaml.YAMLError as e:
            return None, f"Invalid YAML: {e}"

        if not isinstance(recipe_data, dict):
            return None, "Recipe must be a YAML dictionary"

        # Add uploader info to the YAML before storing
        recipe_data["uploader"] = uploader
        if name:
            recipe_data["name"] = name
        if description:
            recipe_data["description"] = description

        # Serialize back to YAML (with added metadata)
        final_yaml = yaml.dump(recipe_data, default_flow_style=False)

        # Write to temp file for caching
        try:
            with tempfile.NamedTemporaryFile(delete=False, suffix=".yaml", mode="w") as tmp:
                tmp.write(final_yaml)
                tmp_path = Path(tmp.name)

            # Store in cache (content-addressed, auto-pins to IPFS)
            cached, ipfs_cid = self.cache.put(tmp_path, node_type="recipe", move=True)
            recipe_id = cached.content_hash

            return recipe_id, None

        except Exception as e:
            return None, f"Failed to cache recipe: {e}"

    async def delete_recipe(self, recipe_id: str, actor_id: str = None) -> Tuple[bool, Optional[str]]:
        """
        Delete a recipe.

        Note: This only removes from local cache. IPFS copies persist.
        Returns (success, error_message).
        """
        # Get recipe to check ownership
        recipe = await self.get_recipe(recipe_id)
        if not recipe:
            return False, "Recipe not found"

        # Check ownership if actor_id provided
        if actor_id:
            recipe_owner = recipe.get("uploader")
            if recipe_owner and recipe_owner != actor_id:
                return False, "Cannot delete: you don't own this recipe"

        # Delete from cache
        try:
            if hasattr(self.cache, 'delete_by_content_hash'):
                success, msg = self.cache.delete_by_content_hash(recipe_id)
                if not success:
                    return False, msg
            else:
                # Fallback: get path and delete directly
                path = self.cache.get_by_content_hash(recipe_id)
                if path and path.exists():
                    path.unlink()

            return True, None
        except Exception as e:
            return False, f"Failed to delete: {e}"

    def parse_yaml(self, yaml_content: str) -> Dict[str, Any]:
        """Parse recipe YAML content."""
        return yaml.safe_load(yaml_content)

    def build_dag(self, recipe: Dict[str, Any]) -> Dict[str, Any]:
        """
        Build DAG visualization data from recipe.

        Returns nodes and edges for Cytoscape.js.
        """
        nodes = []
        edges = []

        dag = recipe.get("dag", {})
        dag_nodes = dag.get("nodes", {})
        output_node = dag.get("output")

        for node_id, node_def in dag_nodes.items():
            node_type = node_def.get("type", "EFFECT")
            nodes.append({
                "data": {
                    "id": node_id,
                    "label": node_id,
                    "nodeType": node_type,
                    "isOutput": node_id == output_node,
                }
            })

            # Build edges from inputs
            for input_ref in node_def.get("inputs", []):
                if isinstance(input_ref, dict):
                    source = input_ref.get("node") or input_ref.get("input")
                else:
                    source = input_ref

                if source:
                    edges.append({
                        "data": {
                            "source": source,
                            "target": node_id,
                        }
                    })

        return {"nodes": nodes, "edges": edges}