"""
Customer Service Agent - Handles FAQ and general inquiries
"""
import json
from typing import Any

from core.state import AgentState, ConversationState, add_tool_call, set_response
from core.llm import get_llm_client, Message
from prompts import get_prompt
from utils.logger import get_logger
from utils.faq_library import get_faq_library

logger = get_logger(__name__)


async def customer_service_agent(state: AgentState) -> AgentState:
    """Customer service agent node

    Handles FAQ, company info, and general inquiries using Strapi MCP tools.

    Args:
        state: Current agent state

    Returns:
        Updated state with tool calls or response
    """
    logger.info(
        "Customer service agent processing",
        conversation_id=state["conversation_id"]
    )

    state["current_agent"] = "customer_service"
    state["agent_history"].append("customer_service")
    state["state"] = ConversationState.PROCESSING.value

    # Check if we have tool results to process
    if state["tool_results"]:
        return await _generate_response_from_results(state)

    # ========== FAST PATH: Check if FAQ was already matched at router ==========
    # Router already checked FAQ and stored response if found
    if "faq_response" in state and state["faq_response"]:
        logger.info(
            "Using FAQ response from router",
            conversation_id=state["conversation_id"],
            response_length=len(state["faq_response"])
        )
        return set_response(state, state["faq_response"])
    # =========================================================================

    # ========== FAST PATH: Check local FAQ library first (backup) ==========
    # This provides instant response for common questions without API calls
    # This is a fallback in case FAQ wasn't matched at router level
    faq_library = get_faq_library()
    faq_response = faq_library.find_match(state["current_message"])

    if faq_response:
        logger.info(
            "FAQ match found, returning instant response",
            conversation_id=state["conversation_id"],
            response_length=len(faq_response)
        )
        return set_response(state, faq_response)
    # ============================================================

    # Get detected language
    locale = state.get("detected_language", "en")

    # Auto-detect category and query FAQ
    message_lower = state["current_message"].lower()

    # 定义分类关键词（支持多语言：en, nl, de, es, fr, it, tr, zh）
    category_keywords = {
        "register": [
            # English
            "register", "sign up", "account", "login", "password", "forgot",
            # Dutch (Nederlands)
            "registreren", "account", "inloggen", "wachtwoord",
            # German (Deutsch)
            "registrieren", "konto", "anmelden", "passwort",
            # Spanish (Español)
            "registrar", "cuenta", "iniciar", "contraseña",
            # French (Français)
            "enregistrer", "compte", "connecter", "mot de passe",
            # Italian (Italiano)
            "registrarsi", "account", "accesso", "password",
            # Turkish (Türkçe)
            "kayıt", "hesap", "giriş", "şifre",
            # Chinese (中文)
            "注册", "账号", "登录", "密码", "忘记密码"
        ],
        "order": [
            # English
            "order", "place order", "cancel order", "modify order", "change order",
            # Dutch
            "bestelling", "bestellen", "annuleren", "wijzigen",
            # German
            "bestellung", "bestellen", "stornieren", "ändern",
            # Spanish
            "pedido", "hacer pedido", "cancelar", "modificar",
            # French
            "commande", "passer commande", "annuler", "modifier",
            # Italian
            "ordine", "ordinare", "cancellare", "modificare",
            # Turkish
            "sipariş", "sipariş ver", "iptal", "değiştir",
            # Chinese
            "订单", "下单", "取消订单", "修改订单", "更改订单"
        ],
        "payment": [
            # English
            "pay", "payment", "checkout", "voucher", "discount", "promo",
            # Dutch
            "betalen", "betaling", "korting", "voucher",
            # German
            "bezahlen", "zahlung", "rabatt", "gutschein",
            # Spanish
            "pagar", "pago", "descuento", "cupón",
            # French
            "payer", "paiement", "réduction", "bon",
            # Italian
            "pagare", "pagamento", "sconto", "voucher",
            # Turkish
            "ödemek", "ödeme", "indirim", "kupon",
            # Chinese
            "支付", "付款", "结算", "优惠券", "折扣", "促销"
        ],
        "shipment": [
            # English
            "ship", "shipping", "delivery", "courier", "transit", "logistics", "tracking",
            # Dutch
            "verzenden", "levering", "koerier", "logistiek", "volgen",
            # German
            "versand", "lieferung", "kurier", "logistik", "verfolgung",
            # Spanish
            "enviar", "envío", "entrega", "mensajería", "logística", "seguimiento",
            # French
            "expédier", "livraison", "coursier", "logistique", "suivi",
            # Italian
            "spedire", "spedizione", "consegna", "corriere", "logistica", "tracciamento",
            # Turkish
            "gönderi", "teslimat", "kurye", "lojistik", "takip",
            # Chinese
            "发货", "配送", "快递", "物流", "运输", "配送单"
        ],
        "return": [
            # English
            "return", "refund", "exchange", "defective", "damaged",
            # Dutch
            "retour", "terugbetaling", "ruilen", "defect",
            # German
            "rückgabe", "erstattung", "austausch", "defekt",
            # Spanish
            "devolución", "reembolso", "cambio", "defectuoso",
            # French
            "retour", "remboursement", "échange", "défectueux",
            # Italian
            "reso", "rimborso", "cambio", "difettoso",
            # Turkish
            "iade", "geri ödeme", "değişim", "defekt",
            # Chinese
            "退货", "退款", "换货", "有缺陷", "损坏"
        ],
    }

    # 检测分类
    detected_category = None
    for category, keywords in category_keywords.items():
        if any(keyword in message_lower for keyword in keywords):
            detected_category = category
            break

    # 检查是否已经查询过 FAQ
    tool_calls = state.get("tool_calls", [])
    has_faq_query = any(tc.get("tool_name") in ["query_faq", "search_knowledge_base"] for tc in tool_calls)

    # 如果检测到分类且未查询过 FAQ，自动查询
    if detected_category and not has_faq_query:
        logger.info(
            f"Auto-querying FAQ for category: {detected_category}",
            conversation_id=state["conversation_id"]
        )

        # 自动添加 FAQ 工具调用
        state = add_tool_call(
            state,
            tool_name="query_faq",
            arguments={
                "category": detected_category,
                "locale": locale,
                "limit": 5
            },
            server="strapi"
        )
        state["state"] = ConversationState.TOOL_CALLING.value
        return state

    # 如果询问营业时间或联系方式，自动查询公司信息
    if any(keyword in message_lower for keyword in ["opening hour", "contact", "address", "phone", "email"]) and not has_faq_query:
        logger.info(
            "Auto-querying company info",
            conversation_id=state["conversation_id"]
        )

        state = add_tool_call(
            state,
            tool_name="get_company_info",
            arguments={
                "section": "contact",
                "locale": locale
            },
            server="strapi"
        )
        state["state"] = ConversationState.TOOL_CALLING.value
        return state
    
    # Build messages for LLM
    # Load prompt in detected language
    system_prompt = get_prompt("customer_service", locale)

    messages = [
        Message(role="system", content=system_prompt),
    ]
    
    # Add conversation history
    for msg in state["messages"][-6:]:
        messages.append(Message(role=msg["role"], content=msg["content"]))
    
    # Add current message
    messages.append(Message(role="user", content=state["current_message"]))
    
    try:
        llm = get_llm_client()
        response = await llm.chat(messages, temperature=0.7)
        
        # Parse response
        content = response.content.strip()
        if content.startswith("```"):
            content = content.split("```")[1]
            if content.startswith("json"):
                content = content[4:]
        
        result = json.loads(content)
        action = result.get("action")
        
        if action == "call_tool":
            # Add tool call to state
            state = add_tool_call(
                state,
                tool_name=result["tool_name"],
                arguments=result.get("arguments", {}),
                server="strapi"
            )
            state["state"] = ConversationState.TOOL_CALLING.value
            
        elif action == "respond":
            state = set_response(state, result["response"])
            state["state"] = ConversationState.GENERATING.value
            
        elif action == "handoff":
            state["requires_human"] = True
            state["handoff_reason"] = result.get("reason", "User request")
            
        return state
        
    except json.JSONDecodeError:
        # LLM returned plain text, use as response
        state = set_response(state, response.content)
        return state
        
    except Exception as e:
        logger.error("Customer service agent failed", error=str(e))
        state["error"] = str(e)
        return state


async def _generate_response_from_results(state: AgentState) -> AgentState:
    """Generate response based on tool results"""

    # Build context from tool results
    tool_context = []
    for result in state["tool_results"]:
        if result["success"]:
            tool_context.append(f"Tool {result['tool_name']} returned:\n{json.dumps(result['data'], ensure_ascii=False, indent=2)}")
        else:
            tool_context.append(f"Tool {result['tool_name']} failed: {result['error']}")

    prompt = f"""Based on the following tool returned information, generate a response to the user.

User question: {state["current_message"]}

Tool returned information:
{chr(10).join(tool_context)}

Please generate a friendly and professional response. If the tool did not return useful information, honestly inform the user and suggest other ways to get help.
Return only the response content, do not return JSON."""

    messages = [
        Message(role="system", content="You are a professional B2B customer service assistant, please answer user questions based on tool returned information."),
        Message(role="user", content=prompt)
    ]

    try:
        llm = get_llm_client()
        response = await llm.chat(messages, temperature=0.7)
        state = set_response(state, response.content)
        return state

    except Exception as e:
        logger.error("Response generation failed", error=str(e))
        state = set_response(state, "Sorry, there was a problem processing your request. Please try again later or contact customer support.")
        return state