import ollama
import json
import asyncio
from config import settings

def _get_client():
    return ollama.Client(host=settings.ollama_host)


def _chat_sync(messages: list, json_format: bool = True) -> str:
    client = _get_client()
    kwargs = {"temperature": 0.7, "num_predict": 4096 if json_format else 1024}
    response = client.chat(
        model=settings.model_name,
        messages=messages,
        **({"format": "json"} if json_format else {}),
        options=kwargs,
    )
    return response["message"]["content"]


async def _chat(messages: list) -> dict:
    loop = asyncio.get_running_loop()
    raw = await loop.run_in_executor(None, lambda: _chat_sync(messages))
    try:
        return json.loads(raw)
    except json.JSONDecodeError as e:
        raise ValueError(f"Ollama returned invalid JSON: {e}. Raw: {raw[:200]}")


async def generate_weekly_menu(pantry_context: dict, user_notes: str | None = None) -> dict:
    """Suggest 8-12 diverse recipes for the week, prioritizing expiring pantry items."""
    user_message = f"""Given my current pantry and recent meal history, suggest 8-12 diverse recipes I could make this week.

PANTRY STATE:
{json.dumps(pantry_context, indent=2)}

GUIDELINES:
- Suggest genuinely good, practical dishes — do NOT limit yourself to only pantry ingredients
- Use pantry ingredients where it makes sense, but freely include recipes that require buying additional items
- Avoid meals eaten in the last 7 days (see recent_meals)
- Include a mix of breakfast, lunch, and dinner options
- Keep each recipe under 60 minutes
- Include full ingredient lists with quantities and units

Respond ONLY with this JSON structure:
{{
  "recipes": [
    {{
      "name": "...",
      "meal_type": "breakfast",
      "ingredients": [{{"name": "...", "quantity": 1.0, "unit": "cup"}}],
      "description": "1-2 sentence description of the dish's flavor and appeal",
      "instructions": "1. ... 2. ... (4-8 numbered steps, 1-2 sentences each)",
      "time_minutes": 20,
      "serves": 2
    }}
  ],
  "notes": "brief explanation of choices"
}}"""

    if user_notes:
        user_message += f"\n\nUSER PREFERENCES:\n{user_notes}"

    messages = [
        {"role": "system", "content": settings.system_prompt},
        {"role": "user", "content": user_message},
    ]

    return await _chat(messages)


async def generate_grocery_list(recipes: list, pantry_context: dict, user_notes: str | None = None) -> dict:
    """Generate a minimal grocery list based on a list of recipes and current pantry."""
    user_message = f"""Given these recipes and current pantry, generate a minimal grocery list.

RECIPES:
{json.dumps(recipes, indent=2)}

CURRENT PANTRY:
{json.dumps(pantry_context["available_ingredients"], indent=2)}

RULES:
- Only list ingredients NOT already sufficiently in the pantry
- Consolidate duplicate ingredients across recipes (buy once)
- Group items by store section (produce, dairy, protein, pantry, frozen, bakery)
- Estimate realistic retail costs in USD
- Prefer bulk when ingredient appears in 3+ recipes

Respond ONLY with this JSON:
{{
  "items": [
    {{
      "name": "...",
      "quantity": 2.0,
      "unit": "lbs",
      "store_section": "produce",
      "estimated_cost": 3.50,
      "used_in_meals": ["Recipe A", "Recipe B"],
      "reason": "not in pantry"
    }}
  ],
  "total_estimate": 45.00,
  "shopping_notes": "..."
}}"""

    if user_notes:
        user_message += f"\n\nUSER PREFERENCES:\n{user_notes}"

    messages = [
        {"role": "system", "content": settings.system_prompt},
        {"role": "user", "content": user_message},
    ]

    return await _chat(messages)


async def generate_grocery_list_from_pantry(pantry_context: dict, user_notes: str | None = None) -> dict:
    """Generate a grocery list based on pantry state alone, without a menu plan."""
    user_message = f"""Given my current pantry, generate a practical grocery list to stock up for the week.

CURRENT PANTRY:
{json.dumps(pantry_context["available_ingredients"], indent=2)}

RULES:
- Suggest ingredients that would complement what's already in the pantry
- Group items by store section (produce, dairy, protein, pantry, frozen, bakery)
- Estimate realistic retail costs in USD
- Focus on versatile staples that enable multiple meals

Respond ONLY with this JSON:
{{
  "items": [
    {{
      "name": "...",
      "quantity": 2.0,
      "unit": "lbs",
      "store_section": "produce",
      "estimated_cost": 3.50,
      "used_in_meals": [],
      "reason": "versatile staple"
    }}
  ],
  "total_estimate": 45.00,
  "shopping_notes": "..."
}}"""

    if user_notes:
        user_message += f"\n\nUSER PREFERENCES:\n{user_notes}"

    messages = [
        {"role": "system", "content": settings.system_prompt},
        {"role": "user", "content": user_message},
    ]

    return await _chat(messages)


async def suggest_recipe(pantry_context: dict) -> dict:
    """Suggest one recipe using available pantry ingredients."""
    user_message = f"""Suggest ONE recipe I can make right now using only these pantry ingredients (plus common staples).

PANTRY:
{json.dumps(pantry_context["available_ingredients"], indent=2)}

Respond ONLY with this JSON:
{{
  "recipe": {{
    "name": "...",
    "meal_type": "dinner",
    "ingredients": [{{"name": "...", "quantity": 1.0, "unit": "cup"}}],
    "instructions": "Step 1... Step 2...",
    "time_minutes": 30,
    "serves": 2
  }}
}}"""

    messages = [
        {"role": "system", "content": settings.system_prompt},
        {"role": "user", "content": user_message},
    ]

    return await _chat(messages)


async def generate_replacement_recipe(meal_type: str, existing_names: list, pantry_context: dict, user_notes: str | None = None) -> dict:
    """Generate a single replacement recipe of the given meal type."""
    user_message = f"""Suggest ONE {meal_type} recipe to replace a dish I don't want.

CURRENT PANTRY:
{json.dumps(pantry_context["available_ingredients"], indent=2)}

ALREADY IN PLAN (do not suggest these):
{json.dumps(existing_names, indent=2)}

GUIDELINES:
- Suggest a genuinely good, practical {meal_type} dish
- Do NOT limit yourself to only pantry ingredients
- Under 60 minutes
- Must not be any of the dishes already in the plan

Respond ONLY with this JSON:
{{
  "recipe": {{
    "name": "...",
    "meal_type": "{meal_type}",
    "ingredients": [{{"name": "...", "quantity": 1.0, "unit": "cup"}}],
    "description": "1-2 sentence description of the dish's flavor and appeal",
    "instructions": "1. ... 2. ... (4-8 numbered steps, 1-2 sentences each)",
    "time_minutes": 30,
    "serves": 2
  }}
}}"""

    if user_notes:
        user_message += f"\n\nUSER PREFERENCES:\n{user_notes}"

    messages = [
        {"role": "system", "content": settings.system_prompt},
        {"role": "user", "content": user_message},
    ]

    return await _chat(messages)


async def get_available_models() -> list:
    """Get list of available Ollama model names."""
    def _list_models_sync():
        client = _get_client()
        try:
            models_resp = client.list()
            return [m["name"] for m in models_resp.get("models", [])]
        except Exception:
            return []

    loop = asyncio.get_running_loop()
    return await loop.run_in_executor(None, _list_models_sync)


async def chat_with_commis(message: str, history: list, pantry_context: dict, menu_context: list, grocery_context: list) -> str:
    """Have a conversation with Commis using full kitchen context."""
    system_prompt = f"""You are Commis, a friendly and knowledgeable personal chef assistant. You have full visibility into the user's kitchen — their pantry, this week's recipe suggestions, and their grocery list. Use this context to give personalized, practical cooking advice.

PANTRY (ingredients on hand):
{json.dumps(pantry_context.get("available_ingredients", []), indent=2)}

EXPIRING SOON:
{json.dumps(pantry_context.get("expiring_soon", []), indent=2)}

RECENT MEALS (last 14 days):
{json.dumps(pantry_context.get("recent_meals", []), indent=2)}

THIS WEEK'S RECIPE SUGGESTIONS:
{json.dumps(menu_context, indent=2)}

GROCERY LIST:
{json.dumps(grocery_context, indent=2)}

Be conversational, helpful, and concise. Reference specific ingredients and recipes by name when relevant. You do not need to respond with JSON."""

    messages = [{"role": "system", "content": system_prompt}]
    messages.extend(history)
    messages.append({"role": "user", "content": message})

    loop = asyncio.get_running_loop()
    return await loop.run_in_executor(None, lambda: _chat_sync(messages, json_format=False))


async def parse_recipe_from_text(text: str) -> dict:
    """Ask Ollama to parse unstructured recipe text into our standard recipe schema."""
    user_message = f"""Parse this recipe text and extract structured data.

RECIPE TEXT:
{text[:4000]}

Respond ONLY with this JSON:
{{
  "recipe": {{
    "name": "...",
    "meal_type": "dinner",
    "ingredients": [{{"name": "...", "quantity": 1.0, "unit": "cup"}}],
    "description": "1-2 sentence description of the dish's flavor and appeal",
    "instructions": "1. ... 2. ... (4-8 numbered steps, 1-2 sentences each)",
    "time_minutes": 30,
    "serves": 2
  }}
}}
meal_type must be one of: breakfast, lunch, dinner, snack"""

    messages = [
        {"role": "system", "content": settings.system_prompt},
        {"role": "user", "content": user_message},
    ]
    return await _chat(messages)


async def generate_single_recipe(description: str, existing_names: list, pantry_context: dict) -> dict:
    """Generate one recipe matching a user description."""
    user_message = f"""Suggest ONE recipe based on this description: "{description}"

CURRENT PANTRY:
{json.dumps(pantry_context["available_ingredients"], indent=2)}

ALREADY IN PLAN (do not suggest these):
{json.dumps(existing_names, indent=2)}

GUIDELINES:
- Match the description as closely as possible
- Do NOT limit yourself to only pantry ingredients
- Under 60 minutes
- Must not be any dish already in the plan

Respond ONLY with this JSON:
{{
  "recipe": {{
    "name": "...",
    "description": "1-2 sentence description of the dish's flavor and appeal",
    "meal_type": "dinner",
    "ingredients": [{{"name": "...", "quantity": 1.0, "unit": "cup"}}],
    "instructions": "1. ... 2. ... (4-8 numbered steps, 1-2 sentences each)",
    "time_minutes": 30,
    "serves": 2
  }}
}}
meal_type must be one of: breakfast, lunch, dinner, snack"""

    messages = [
        {"role": "system", "content": settings.system_prompt},
        {"role": "user", "content": user_message},
    ]
    return await _chat(messages)