import asyncio
import json
from fastapi import FastAPI, Request
from fastapi.responses import JSONResponse
from models import ChatRequest, ChatResponse, RocketChatWebhook
from config import settings
from security import (
    detect_injection,
    is_off_topic,
    check_rate_limit,
    store_messages,
    get_session_mode,
    set_session_mode,
    get_redis,
)
from llm import get_ai_response
from rocketchat import get_or_create_room, send_message
from twenty_crm import create_lead_in_crm, save_conversation_transcript

app = FastAPI(title="AImpress Chatbot API", docs_url=None, redoc_url=None)


@app.get("/api/chat/health")
async def health():
    return {"status": "ok"}


@app.post("/api/chat")
async def chat(req: ChatRequest):
    # Rate limit check
    limited, count = await check_rate_limit(req.session_id)
    if limited:
        # Save transcript to CRM on rate limit (end of conversation)
        r_rl = await get_redis()
        meta_raw_rl = await r_rl.get(f"chat:meta:{req.session_id}")
        if meta_raw_rl:
            meta_rl = json.loads(meta_raw_rl)
            person_id = meta_rl.get("twenty_person_id")
            if person_id and not meta_rl.get("transcript_saved"):
                raw_msgs = await r_rl.lrange(f"chat:history:{req.session_id}", 0, -1)
                msgs = [json.loads(m) for m in raw_msgs]
                lead_name = meta_rl.get("lead", {}).get("name", "Visitor")
                asyncio.create_task(save_conversation_transcript(person_id, msgs, lead_name))
                meta_rl["transcript_saved"] = True
                await r_rl.set(f"chat:meta:{req.session_id}", json.dumps(meta_rl), ex=settings.conversation_ttl)
        return ChatResponse(
            reply="You've reached the message limit for this session. Please leave your contact details at hello@ai-impress.com and we'll follow up personally.",
            sender="bot",
            session_id=req.session_id,
            message_count=count,
            rate_limited=True,
        )

    # Message length validation (Pydantic handles max_length, but double-check)
    message = req.message[:settings.max_message_length]

    # Prompt injection detection
    if detect_injection(message):
        return ChatResponse(
            reply="I'm here to help with AImpress services. What can I assist you with today?",
            sender="bot",
            session_id=req.session_id,
            message_count=count,
        )

    # Check session mode (AI vs human takeover)
    mode = await get_session_mode(req.session_id)

    if mode == "human":
        # Store message and forward to Rocket.Chat only
        messages = await store_messages(req.session_id, "user", message)
        room_id = await get_or_create_room(req.session_id)
        if room_id:
            asyncio.create_task(send_message(room_id, req.session_id, message, "visitor"))
        return ChatResponse(
            reply="",  # Empty — waiting for human response via webhook
            sender="human",
            session_id=req.session_id,
            message_count=count,
        )

    # Off-topic filter (lenient — only rejects clearly off-topic messages)
    if is_off_topic(message):
        reply = "I'm here to help with AImpress AI and automation services. What would you like to know about our solutions?"
        await store_messages(req.session_id, "user", message)
        await store_messages(req.session_id, "assistant", reply)
        return ChatResponse(
            reply=reply,
            sender="bot",
            session_id=req.session_id,
            message_count=count,
        )

    # Store user message and get conversation history
    messages = await store_messages(req.session_id, "user", message)

    # Load session meta (twenty_person_id, lead info, etc.)
    r = await get_redis()
    meta_raw = await r.get(f"chat:meta:{req.session_id}")
    session_meta = json.loads(meta_raw) if meta_raw else {}
    session_meta["page_context"] = req.page_context

    # If lead info provided (first message), save to session meta + create CRM lead
    if req.lead and req.lead.name and "lead" not in session_meta:
        lead_info = {"name": req.lead.name}
        if req.lead.email:
            lead_info["email"] = req.lead.email
        if req.lead.company:
            lead_info["company"] = req.lead.company
        session_meta["lead"] = lead_info

        # Create lead in Twenty CRM immediately from form data
        person_id = await create_lead_in_crm(
            name=req.lead.name,
            email=req.lead.email or "",
            company=req.lead.company or "",
            need=message,
            page_context=req.page_context or "/",
        )
        if person_id:
            session_meta["twenty_person_id"] = person_id

    # Always prepend lead context from session meta (persists across messages)
    stored_lead = session_meta.get("lead")
    if stored_lead:
        lead_context = f"[System: The visitor has introduced themselves. Name: {stored_lead['name']}"
        if stored_lead.get("email"):
            lead_context += f", Email: {stored_lead['email']}"
        if stored_lead.get("company"):
            lead_context += f", Company: {stored_lead['company']}"
        lead_context += ". Their lead is ALREADY captured in CRM — do NOT call capture_lead again."
        lead_context += " Use this info naturally — greet them by name. Don't re-ask for info you already have."
        lead_context += " IMPORTANT: Whenever the visitor mentions budget, timeline, requirements, job title, phone, city, or any useful detail — IMMEDIATELY call update_lead with the 'note' field to enrich their CRM profile.]"
        messages = [{"role": "user", "content": lead_context}, {"role": "assistant", "content": "Understood. I'll use update_lead to enrich their profile whenever they share new details."}] + messages

    # Prepend language hint for non-English visitors
    if req.language == "uk":
        messages = [
            {"role": "user", "content": "[System: The visitor's interface language is Ukrainian. Default to Ukrainian in your responses unless they write in English.]"},
            {"role": "assistant", "content": "Зрозуміло. Я буду відповідати українською."},
        ] + messages

    # Get AI response
    try:
        reply, lead_data = await get_ai_response(messages, session_meta)
    except Exception as e:
        reply = "I'm sorry, I'm having a technical issue. Please try again or contact us at hello@ai-impress.com."
        print(f"LLM error: {e}")
        lead_data = None

    # Handle escalation to human if triggered
    escalation = session_meta.pop("_escalate", None)
    if escalation:
        await set_session_mode(req.session_id, "human")
        # Save conversation transcript to CRM on escalation
        person_id = session_meta.get("twenty_person_id")
        if person_id:
            visitor_name = stored_lead.get("name", "Visitor") if stored_lead else "Visitor"
            asyncio.create_task(save_conversation_transcript(person_id, messages, visitor_name))

    # Persist session meta (may contain new twenty_person_id)
    await r.set(f"chat:meta:{req.session_id}", json.dumps(session_meta), ex=settings.conversation_ttl)

    # Store bot reply
    await store_messages(req.session_id, "assistant", reply)

    # Mirror to Rocket.Chat (async, don't block response)
    visitor_name = req.lead.name if req.lead and req.lead.name else "Website Visitor"
    room_id = await get_or_create_room(req.session_id, visitor_name)
    if room_id:
        asyncio.create_task(send_message(room_id, req.session_id, message, "visitor"))
        asyncio.create_task(send_message(room_id, req.session_id, reply, "bot"))
        # Notify RC agent about escalation
        if escalation:
            notice = f"⚡ ESCALATION: {escalation['reason']}\n📋 Summary: {escalation['summary']}"
            asyncio.create_task(send_message(room_id, req.session_id, notice, "bot"))

    return ChatResponse(
        reply=reply,
        sender="bot",
        session_id=req.session_id,
        message_count=count,
    )


@app.post("/api/chat/webhook/rocketchat")
async def rocketchat_webhook(req: Request):
    """Webhook from Rocket.Chat when a manager sends a message."""
    body = await req.json()

    # RC livechat webhook format: {_id, visitor, agent, messages, type}
    messages_list = body.get("messages", [])
    visitor = body.get("visitor", {})
    session_id = visitor.get("token", "")

    if not messages_list or not session_id:
        return {"status": "ignored"}

    r = await get_redis()

    for msg in messages_list:
        text = msg.get("msg", "")
        sender_username = msg.get("u", {}).get("username", "")
        sender_name = msg.get("u", {}).get("name", sender_username)

        # Skip messages from visitors (our own bot echo) — only process agent messages
        if sender_username == visitor.get("username", ""):
            continue

        if not text:
            continue

        # Strip bot emoji prefix if present
        if text.startswith("🤖 "):
            continue

        # Check for /ai command to resume AI mode
        if text.strip().lower() == "/ai":
            await set_session_mode(session_id, "ai")
            return {"status": "ai_resumed"}

        # Set session to human mode and store the manager's message
        await set_session_mode(session_id, "human")
        await store_messages(session_id, "assistant", f"[{sender_name}] {text}")
        # Store for polling delivery to frontend
        await r.rpush(
            f"chat:pending:{session_id}",
            json.dumps({"sender": "human", "text": text, "agent": sender_name}),
        )
        await r.expire(f"chat:pending:{session_id}", 300)

    return {"status": "delivered"}


@app.get("/api/chat/pending/{session_id}")
async def get_pending_messages(session_id: str):
    """Poll for pending human messages (Phase 1 polling, Phase 2 SSE)."""
    from security import get_redis
    import json
    r = await get_redis()
    key = f"chat:pending:{session_id}"
    raw = await r.lrange(key, 0, -1)
    await r.delete(key)
    messages = [json.loads(m) for m in raw]
    return {"messages": messages}