# app.py -- KC Robot AI V4.0 (Cloud Brain)
# Flask server: Chat (HF), TTS, STT, Telegram poller, REST API cho ESP32
# Setup: set env HF_API_TOKEN, (optional) HF_MODEL, HF_TTS_MODEL, HF_STT_MODEL, TELEGRAM_TOKEN
# requirements: see requirements.txt

import os
import io
import time
import json
import threading
import logging
from typing import Optional, List, Tuple

import requests
from flask import Flask, request, jsonify, send_file, render_template_string

logging.basicConfig(level=logging.INFO)
logger = logging.getLogger("kcrobot.v4")

app = Flask(__name__)

# ====== Config from env / Secrets ======
HF_API_TOKEN = os.getenv("HF_API_TOKEN", "")
HF_MODEL = os.getenv("HF_MODEL", "google/flan-t5-large")
HF_TTS_MODEL = os.getenv("HF_TTS_MODEL", "facebook/tts_transformer-es-css10")
HF_STT_MODEL = os.getenv("HF_STT_MODEL", "openai/whisper-small")
TELEGRAM_TOKEN = os.getenv("TELEGRAM_TOKEN", "")
PORT = int(os.getenv("PORT", os.getenv("SERVER_PORT", 7860)))

if not HF_API_TOKEN:
    logger.warning("HF_API_TOKEN not set. Put HF_API_TOKEN in Secrets.")

HF_HEADERS = {"Authorization": f"Bearer {HF_API_TOKEN}"} if HF_API_TOKEN else {}

# ====== In-memory storage (simple) ======
# conversation: list of (user, bot) pairs
CONV: List[Tuple[str,str]] = []
# display_lines for ESP32 OLED (last few lines)
DISPLAY_LINES: List[str] = []

# helper to maintain display buffer
def push_display(line: str, limit=6):
    global DISPLAY_LINES
    DISPLAY_LINES.append(line)
    if len(DISPLAY_LINES) > limit:
        DISPLAY_LINES = DISPLAY_LINES[-limit:]

# ====== HuggingFace helpers (REST inference) ======
def hf_text_generate(prompt: str, model: Optional[str] = None, max_new_tokens: int = 256, temperature: float = 0.7) -> str:
    model = model or HF_MODEL
    url = f"/static-proxy?url=https%3A%2F%2Fapi-inference.huggingface.co%2Fmodels%2F%7Bmodel%7D"
    payload = {
        "inputs": prompt,
        "parameters": {"max_new_tokens": int(max_new_tokens), "temperature": float(temperature)},
        "options": {"wait_for_model": True}
    }
    r = requests.post(url, headers=HF_HEADERS, json=payload, timeout=120)
    if r.status_code != 200:
        logger.error("HF text gen error %s: %s", r.status_code, r.text[:200])
        raise RuntimeError(f"HF text generation failed: {r.status_code}: {r.text}")
    data = r.json()
    # parse common shapes
    if isinstance(data, list) and len(data) and isinstance(data[0], dict):
        return data[0].get("generated_text", "") or str(data[0])
    if isinstance(data, dict) and "generated_text" in data:
        return data.get("generated_text", "")
    return str(data)

def hf_tts_get_mp3(text: str, model: Optional[str] = None) -> bytes:
    model = model or HF_TTS_MODEL
    url = f"/static-proxy?url=https%3A%2F%2Fapi-inference.huggingface.co%2Fmodels%2F%7Bmodel%7D"
    payload = {"inputs": text}
    headers = dict(HF_HEADERS)
    headers["Content-Type"] = "application/json"
    r = requests.post(url, headers=headers, json=payload, stream=True, timeout=120)
    if r.status_code != 200:
        logger.error("HF TTS error %s: %s", r.status_code, r.text[:200])
        raise RuntimeError(f"HF TTS failed: {r.status_code}: {r.text}")
    return r.content

def hf_stt_from_bytes(audio_bytes: bytes, model: Optional[str] = None) -> str:
    model = model or HF_STT_MODEL
    url = f"/static-proxy?url=https%3A%2F%2Fapi-inference.huggingface.co%2Fmodels%2F%7Bmodel%7D"
    headers = dict(HF_HEADERS)
    headers["Content-Type"] = "application/octet-stream"
    r = requests.post(url, headers=headers, data=audio_bytes, timeout=180)
    if r.status_code != 200:
        logger.error("HF STT error %s: %s", r.status_code, r.text[:200])
        raise RuntimeError(f"HF STT failed: {r.status_code}: {r.text}")
    j = r.json()
    # common: {"text":"..."}
    if isinstance(j, dict) and "text" in j:
        return j["text"]
    # fallback
    return str(j)

# ====== Core endpoints for ESP32 ======
@app.route("/ask", methods=["POST"])
def api_ask():
    """ESP32 or web call: JSON {text, lang (opt)} -> returns {"answer": "..."}"""
    data = request.get_json(force=True)
    text = data.get("text","").strip()
    lang = data.get("lang","auto")
    if not text:
        return jsonify({"error":"no text"}), 400
    # build instructive prompt to encourage clear Vietnamese/English responses
    if lang == "vi":
        prompt = "Bạn là trợ lý thông minh, trả lời bằng tiếng Việt, rõ ràng và ngắn gọn:\n\n" + text
    elif lang == "en":
        prompt = "You are a helpful assistant. Answer in clear English, concise:\n\n" + text
    else:
        # auto: simple system instruction bilingual
        prompt = "Bạn là trợ lý thông minh song ngữ (Vietnamese/English). Trả lời bằng ngôn ngữ phù hợp với câu hỏi.\n\n" + text
    try:
        ans = hf_text_generate(prompt)
    except Exception as e:
        logger.exception("ask failed")
        return jsonify({"error": str(e)}), 500
    # store conversation and display
    CONV.append((text, ans))
    push_display("YOU: " + (text[:40]))
    push_display("BOT: " + (ans[:40]))
    return jsonify({"answer": ans})

@app.route("/tts", methods=["POST"])
def api_tts():
    """POST JSON {text: "..."} -> return audio/mpeg bytes (mp3 or wav)"""
    data = request.get_json(force=True)
    text = data.get("text","").strip()
    if not text:
        return jsonify({"error":"no text"}), 400
    try:
        audio = hf_tts_get_mp3(text)
    except Exception as e:
        logger.exception("tts failed")
        return jsonify({"error": str(e)}), 500
    return send_file(
        io.BytesIO(audio),
        mimetype="audio/mpeg",
        as_attachment=False,
        download_name="tts.mp3"
    )

@app.route("/stt", methods=["POST"])
def api_stt():
    """
    Accepts raw audio bytes in body OR multipart 'file'.
    Returns JSON {"text": "..."}
    """
    if "file" in request.files:
        f = request.files["file"]
        audio_bytes = f.read()
    else:
        audio_bytes = request.get_data()
    if not audio_bytes:
        return jsonify({"error":"no audio"}), 400
    try:
        text = hf_stt_from_bytes(audio_bytes)
    except Exception as e:
        logger.exception("stt failed")
        return jsonify({"error": str(e)}), 500
    # push to display
    push_display("UserAudio: " + (text[:40]))
    return jsonify({"text": text})

@app.route("/presence", methods=["POST"])
def api_presence():
    """
    ESP32 radar -> POST JSON {"event":"presence","note": "..."}.
    Server: will announce greeting (call TTS) and send Telegram alert.
    """
    data = request.get_json(force=True)
    note = data.get("note","Có người tới")
    # create greeting text
    greeting = f"Xin chào! {note}"
    # store
    CONV.append(("__presence__", greeting))
    push_display("RADAR: " + note[:40])
    # Telegram notify
    if TELEGRAM_TOKEN:
        try:
            send_telegram_message(f"⚠️ Robot: Phát hiện người - {note}")
        except Exception:
            logger.exception("telegram notify failed")
    # Return greeting so ESP can call /tts to download and play (or include mp3 directly)
    return jsonify({"greeting": greeting})

@app.route("/display", methods=["GET"])
def api_display():
    """ESP32 GET -> returns last display lines to show on OLED."""
    return jsonify({"lines": DISPLAY_LINES, "conv_len": len(CONV)})

# ====== Web UI (simple mobile-friendly) ======
INDEX_HTML = """
<!doctype html>
<html>
<head>
  <meta charset="utf-8">
  <title>KC Robot AI V4.0</title>
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <style>
    body{font-family:Arial,Helvetica;color:#111;margin:10px;padding:0}
    .box{max-width:900px;margin:auto}
    textarea{width:100%;height:80px;padding:8px;font-size:16px}
    button{padding:10px 16px;margin-top:6px;font-size:16px}
    #chat{border:1px solid #ddd;padding:8px;height:320px;overflow:auto;background:#f9f9f9}
    .msg-user{color:#006; margin:6px 0}
    .msg-bot{color:#080; margin:6px 0}
  </style>
</head>
<body>
  <div class="box">
    <h2>🤖 KC Robot AI V4.0 — Cloud Brain</h2>
    <div id="chat"></div>
    <textarea id="txt" placeholder="Nhập tiếng Việt hoặc English..."></textarea><br>
    <button onclick="send()">Gửi (Ask)</button>
    <button onclick="playLastTTS()">Phát TTS trả lời</button>
    <hr/>
    <input type="file" id="audiofile" accept="audio/*"><button onclick="uploadAudio()">Upload audio → STT</button>
    <hr/>
    <h4>Logs</h4><div id="log"></div>
  </div>
<script>
async function send(){
  const txt = document.getElementById('txt').value;
  if(!txt) return;
  appendUser(txt);
  document.getElementById('txt').value='';
  const res = await fetch('/ask',{method:'POST',headers:{'Content-Type':'application/json'}, body: JSON.stringify({text: txt})});
  const j = await res.json();
  if(j.answer){
    appendBot(j.answer);
    // cache last answer for TTS
    window._lastAnswer = j.answer;
  } else {
    appendBot('[Error] '+JSON.stringify(j));
  }
}
function appendUser(t){document.getElementById('chat').innerHTML += '<div class="msg-user"><b>You:</b> '+escapeHtml(t)+'</div>'; scrollChat();}
function appendBot(t){document.getElementById('chat').innerHTML += '<div class="msg-bot"><b>Robot:</b> '+escapeHtml(t)+'</div>'; scrollChat();}
function scrollChat(){let c=document.getElementById('chat'); c.scrollTop = c.scrollHeight;}
function escapeHtml(s){ return s.replace(/&/g,'&amp;').replace(/</g,'&lt;').replace(/>/g,'&gt;');}
async function playLastTTS(){
  const txt = window._lastAnswer || '';
  if(!txt){ alert('Chưa có câu trả lời để phát'); return; }
  const r = await fetch('/tts',{method:'POST',headers:{'Content-Type':'application/json'},body: JSON.stringify({text:txt})});
  if(r.ok){
    const blob = await r.blob();
    const url = URL.createObjectURL(blob);
    const a = new Audio(url);
    a.play();
  } else {
    alert('TTS lỗi');
  }
}
async function uploadAudio(){
  const f = document.getElementById('audiofile').files[0];
  if(!f){ alert('Chọn file audio'); return; }
  const fd = new FormData(); fd.append('file', f);
  const r = await fetch('/stt', {method:'POST', body: fd});
  const j = await r.json();
  if(j.text){ appendUser('[voice] '+j.text); window._lastSTT = j.text; }
  else appendUser('[stt error] '+JSON.stringify(j));
}
// simple logger
function log(msg){ document.getElementById('log').innerText += '\\n'+msg; }
</script>
</body>
</html>
"""

@app.route("/", methods=["GET"])
def index():
    return render_template_string(INDEX_HTML)

# ====== Telegram integration (polling minimal) ======
def send_telegram_message(text: str):
    if not TELEGRAM_TOKEN:
        logger.warning("Telegram token not set")
        return
    url = f"https://api.telegram.org/bot{TELEGRAM_TOKEN}/sendMessage"
    payload = {"chat_id": os.getenv("TELEGRAM_CHATID", ""), "text": text}
    try:
        r = requests.post(url, json=payload, timeout=10)
        if not r.ok:
            logger.warning("Telegram send failed: %s %s", r.status_code, r.text)
    except Exception:
        logger.exception("send_telegram_message error")

def telegram_poll_loop(server_url: str):
    if not TELEGRAM_TOKEN:
        logger.info("No TELEGRAM_TOKEN -> telegram disabled")
        return
    logger.info("Starting Telegram poller")
    offset = None
    base = f"https://api.telegram.org/bot{TELEGRAM_TOKEN}"
    while True:
        try:
            params = {"timeout": 30}
            if offset:
                params["offset"] = offset
            r = requests.get(base + "/getUpdates", params=params, timeout=35)
            if r.status_code != 200:
                time.sleep(2); continue
            j = r.json()
            for u in j.get("result", []):
                offset = u["update_id"] + 1
                msg = u.get("message") or {}
                chat = msg.get("chat", {})
                chat_id = chat.get("id")
                text = (msg.get("text") or "").strip()
                if not text:
                    continue
                logger.info("TG msg %s: %s", chat_id, text)
                # commands: /ask , /say, /status
                if text.lower().startswith("/ask "):
                    q = text[5:].strip()
                    try:
                        ans = hf_text_generate(q)
                    except Exception as e:
                        ans = f"[HF error] {e}"
                    # reply
                    try:
                        requests.post(base + "/sendMessage", json={"chat_id": chat_id, "text": ans}, timeout=10)
                    except Exception:
                        logger.exception("tg reply failed")
                elif text.lower().startswith("/say "):
                    tts_text = text[5:].strip()
                    # get mp3 and send as audio
                    try:
                        mp3 = hf_tts_get_mp3(tts_text)
                        files = {"audio": ("reply.mp3", mp3, "audio/mpeg")}
                        requests.post(base + "/sendAudio", files=files, data={"chat_id": chat_id}, timeout=30)
                    except Exception:
                        logger.exception("tg say failed")
                elif text.lower().startswith("/status"):
                    try:
                        requests.post(base + "/sendMessage", json={"chat_id": chat_id, "text": "Robot brain running"}, timeout=10)
                    except Exception:
                        pass
                else:
                    # default help
                    try:
                        requests.post(base + "/sendMessage", json={"chat_id": chat_id, "text": "Commands: /ask <q> | /say <text> | /status"}, timeout=10)
                    except Exception:
                        pass
        except Exception:
            logger.exception("telegram poll loop exception")
            time.sleep(3)

# ====== Background threads startup ======
def start_background():
    # Start telegram thread if token exists
    if TELEGRAM_TOKEN:
        t = threading.Thread(target=telegram_poll_loop, args=(f"http://127.0.0.1:{PORT}",), daemon=True)
        t.start()
        logger.info("Telegram poller started.")
    else:
        logger.info("Telegram not configured.")

# start background when app runs
@app.before_first_request
def _startup():
    start_background()

# ====== run ======
if __name__ == "__main__":
    start_background()
    logger.info(f"Starting server on port {PORT}")
    app.run(host="0.0.0.0", port=PORT)